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Sample records for transient myocardial ischaemia

  1. Thrombolysis significantly reduces transient myocardial ischaemia following first acute myocardial infarction

    DEFF Research Database (Denmark)

    Mickley, H; Pless, P; Nielsen, J R

    1992-01-01

    In order to investigate whether thrombolysis affects residual myocardial ischaemia, we prospectively performed a predischarge maximal exercise test and early out-of-hospital ambulatory ST segment monitoring in 123 consecutive men surviving a first acute myocardial infarction (AMI). Seventy...... less than 0.02). Thrombolysis resulted in a non-significant reduction in exercise-induced ST segment depression: prevalence 43% vs 62% in controls. However, during ambulatory monitoring the duration of transient myocardial ischaemia was significantly reduced in thrombolysed patients: 322 min vs 1144...... myocardial ischaemia. This may explain the improvement in myocardial function during physical activities, which was also observed in this study....

  2. Prognostic significance of transient myocardial ischaemia after first acute myocardial infarction: five year follow up study

    DEFF Research Database (Denmark)

    Mickley, H; Nielsen, J R; Berning, J

    1995-01-01

    , and echocardiography in patients with documented ischaemic heart disease. DESIGN: Prospective study. SETTING: Cardiology department of a teaching hospital. PATIENTS: 123 consecutive men aged under 70 who were able to perform predischarge maximal exercise testing. INTERVENTIONS: Echocardiography two days before...... discharge (left ventricular ejection fraction), maximal bicycle ergometric testing one day before discharge (ST segment depression, angina, blood pressure, heart rate), and ambulatory ST segment monitoring (transient myocardial ischaemia) started at hospital discharge a mean of 11 (SD 5) days after...

  3. Transient myocardial ischaemia during ambulatory monitoring out of hospital in patients with chronic stable angina pectoris

    DEFF Research Database (Denmark)

    Egstrup, K

    1988-01-01

    Transient myocardial ischaemia during daily life, detected by ambulatory electrocardiographic monitoring, was investigated in 42 patients with chronic stable angina and documented coronary artery disease. Ambulatory monitoring was initiated for 36 hours after all prophylactic antianginal medication...... monitoring was significantly lower than heart rate at the onset of ST-segment change during exercise testing (100.2 +/- 14.6 vs. 115.8 +/- 19.6 beats/min, p less than 0.01), which may indicate different pathophysiological mechanisms. Transient impairment in coronary oxygen supply seems to be of importance...... with and without symptoms was observed, the highest frequency being in the morning hours. Transient myocardial ischaemia was more frequent in patients with double or triple vessel disease, compared with single vessel disease, but with a great variation. Heart rate at the onset of ischaemia during ambulatory...

  4. Multifractal and nonlinear assessment of autonomous nervous system response during transient myocardial ischaemia

    International Nuclear Information System (INIS)

    Magrans, R; Gomis, P; Caminal, P; Wagner, G

    2010-01-01

    We assess autonomic nervous system response during prolonged percutaneous transluminal coronary angioplasty (PTCA) using heart rate variability analysis with multifractal indices. These indices are used to evaluate the effects of the PTCA procedures at different arteries and locations. A total of 55 patients from the Staff3 database, with no prior history of myocardial infarction, were included in the study. The indices increased significantly during the transient ischaemia and reperfusion periods, indicating an increase in nonlinear multifractal characteristics and a change in temporal correlations in heartbeat fluctuations. This indicates that significant multifractal and nonlinear complex reactions in the autonomic control of the heart rate occurred during coronary artery occlusions and suggests that the multifractal indices may be a promising nonlinear technique for evaluating autonomic nervous system response in the presence of transient myocardial ischaemia

  5. The sensitivity of the symptom angina pectoris as a marker of transient myocardial ischaemia in chronic stable angina pectoris

    DEFF Research Database (Denmark)

    Egstrup, K

    1987-01-01

    with a history of chronic stable angina pectoris, positive exercise test and/or positive coronary angiography, and a correlation was made between the episodes of chest pain and ST segment change. The patients were grouped according to the results of exercise testing and coronary arteriography, and one group...... was studied with and without antianginal medication. Overall, 195 episodes of angina were noted, only 94 of which (48%) were accompanied by ST segment depression. Pain and ST segment changes were best correlated in patients with a positive exercise test, positive angiography and who were not receiving...... as was previously thought, a finding which supports the use of objective methods in identifying episodes of transient myocardial ischaemia in daily life....

  6. Myocardial ischaemia in children with sickle cell disease.

    Science.gov (United States)

    de Montalembert, M; Maunoury, C; Acar, P; Brousse, V; Sidi, D; Lenoir, G

    2004-04-01

    The heart may be involved in children affected with sickle cell disease (SCD) via several mechanisms. Principally, chronic anaemia increases cardiac output and may cause left ventricular enlargement and cardiac insufficiency. To investigate whether the heart also suffers from ischaemia in SCD, as has already been shown for other organs (bone, brain, etc), and to look for risk factors predisposing to this complication. Twenty two children with SCD, and chest pain or ECG or echocardiographic signs (left ventricle dilation or hypokinesis) suggesting myocardial ischaemia were subjected to thallium-201 (201Tl) single photon emission computed tomography (SPECT). Eight children had a normal SPECT, 14 an abnormal one. Myocardial perfusion defects were reversible in nine, fixed in five. Patients with perfusion defects tended to be older and have more severe disease. Five had had cardiac symptoms (episodes of cardiac failure in three, ventricular fibrillation in one, angina in one). Myocardial perfusion was reassessed after six months of hydroxyurea treatment in three patients, and was found to be improved. Myocardial perfusion defects are present in children with SCD and may be demonstrated using SPECT. Hydroxyurea improved perfusion in three patients.

  7. Transient myocardial ischemia after myocardial infarction

    DEFF Research Database (Denmark)

    Mickley, H

    1995-01-01

    the prevalence of ambulatory or transient myocardial ischemia is lower than in patients with chronic, stable coronary artery disease. A greater proportion of ischemic episodes, however, are silent than in other subgroups with ischemic heart disease. Early after the infarction, transient myocardial ischemia...... exhibits a circadian variation with a peak activity occurring in the late evening hours. Patients with non-Q wave infarction have more transient myocardial ischemia, whereas thrombolytic therapy seems to result in less residual ischemia. Exercise testing is more sensitive than ambulatory monitoring...

  8. Effect of 5-aminosalicylic acid on myocardial capillary permeability following ischaemia and reperfusion

    DEFF Research Database (Denmark)

    Hansen, P R; Svendsen, Jesper Hastrup; Høst, N B

    1992-01-01

    The aim was to evaluate the effect of 5-aminosalicylic acid on myocardial capillary permeability for small hydrophilic molecules after ischaemia and reperfusion.......The aim was to evaluate the effect of 5-aminosalicylic acid on myocardial capillary permeability for small hydrophilic molecules after ischaemia and reperfusion....

  9. Lack of indication of myocardial cell damage after myocardial ischaemia in patients with severe stable angina

    DEFF Research Database (Denmark)

    Hansen, Knud Nørregaard; Egstrup, K; Nielsen, J R

    1992-01-01

    To evaluate myocardial cell damage in relation to spontaneous and exercise-induced ischaemia, release of myoglobin, creatine kinase (CK) and its isoenzyme MB (CK-MB) into the serum was estimated in 10 patients with severe stable angina. All patients had a positive exercise test, significant steno...

  10. Hypoxaemia and myocardial ischaemia during and after endoscopic cholangiopancreatography: call for further studies

    DEFF Research Database (Denmark)

    Rosenberg, J; Jørgensen, L N; Rasmussen, Verner

    1992-01-01

    Sixteen non-selected patients undergoing endoscopic cholangiopancreatography (ERCP) after diazepam premedication were monitored for oxygen saturation (SpO2) with a pulse oximeter and for myocardial ischaemia with a Holter tape recorder from 2 h before ERCP to 6 h after the procedure. One patient......, ischaemia without tachycardia in no patients, and isolated tachycardia in 1 patient. There was no significant correlation between diazepam dose and SpO2 during endoscopy. These results suggest tachycardia to be more important than hypoxaemia in the pathogenesis of myocardial ischaemia during upper...

  11. Quantitative detection of myocardial ischaemia by stress echocardiography; a comparison with SPECT

    Science.gov (United States)

    Gudmundsson, Petri; Shahgaldi, Kambiz; Winter, Reidar; Dencker, Magnus; Kitlinski, Mariusz; Thorsson, Ola; Willenheimer, Ronnie B; Ljunggren, Lennart

    2009-01-01

    Aims Real-time perfusion (RTP) adenosine stress echocardiography (ASE) can be used to visually evaluate myocardial ischaemia. The RTP power modulation technique angio-mode (AM), provides images for off-line perfusion quantification using Qontrast® software, generating values of peak signal intensity (A), myocardial blood flow velocity (β) and myocardial blood flow (Axβ). By comparing rest and stress values, their respective reserve values (A-r, β-r, Axβ-r) are generated. We evaluated myocardial ischaemia by RTP-ASE Qontrast® quantification, compared to visual perfusion evaluation with 99mTc-tetrofosmin single-photon emission computed tomography (SPECT). Methods and Results Patients admitted to SPECT underwent RTP-ASE (SONOS 5500) using AM during Sonovue® infusion, before and throughout adenosine stress, also used for SPECT. Visual myocardial perfusion and wall motion analysis, and Qontrast® quantification, were blindly compared to one another and to SPECT, at different time points off-line. We analyzed 201 coronary territories (left anterior descendent [LAD], left circumflex [LCx] and right coronary [RCA] artery territories) in 67 patients. SPECT showed ischaemia in 18 patients and 19 territories. Receiver operator characteristics and kappa values showed significant agreement with SPECT only for β-r and Axβ-r in all segments: area under the curve 0.678 and 0.665; P < 0.001 and < 0.01, respectively. The closest agreements were seen in the LAD territory: kappa 0.442 for both β-r and Axβ-r; P < 0.01. Visual evaluation of ischaemia showed good agreement with SPECT: accuracy 93%; kappa 0.67; P < 0.001; without non-interpretable territories. Conclusion In this agreement study with SPECT, RTP-ASE Qontrast® quantification of myocardial ischaemia was less accurate and less feasible than visual evaluation and needs further development to be clinically useful. PMID:19534829

  12. Polysensory response characteristics of dorsal root ganglion neurones that may serve sensory functions during myocardial ischaemia.

    Science.gov (United States)

    Huang, M H; Horackova, M; Negoescu, R M; Wolf, S; Armour, J A

    1996-09-01

    To determine the response characteristics of dorsal root ganglion neurones that may serve sensory functions during myocardial ischaemia. Extracellular recordings were made from 54 spontaneously active and 5 normally quiescent dorsal root ganglion neurones (T2-T5) in 22 anaesthetized open-chest dogs under control conditions and during epicardial mechanical or chemical stimulation and myocardial ischaemia. The activity of 78% of spontaneously active and all quiescent neurones with left ventricular sensory fields was modified by left ventricular ischaemia. Forty-six spontaneously active neurones (85%) were polysensory with respect to mechanical and chemical stimuli. The 5 quiescent neurones responded only to chemical stimuli. Spontaneously active neurones associated with left ventricular mechanosensory endings (37 neurones) generated four different activity patterns in response to similar mechanical stimuli (high or low pressure active, high-low pressure active, high-low pressure inactive). A fifth group generated activity which was not related to chamber dynamics. Adenosine, adenosine 5'-triphosphate, substance P and bradykinin modified 72, 61, 65 and 63% of the spontaneously active neurones, respectively. Maximum local mechanical or chemical stimuli enhanced activity to similar degrees, as did ischaemia. Each ischaemia-sensitive neurone displayed unique activity patterns in response to similar mechanical or chemical stimuli. Most myocardial ischemia-sensitive dorsal root ganglion neurones associated with epicardial neurites sense mechanical and multiple chemical stimuli, a small population sensing only mechanical or chemical stimuli. Activity patterns generated by these neurones depend on their primary sensory characteristics or those of other neurones that may converge on them, as well as the type and magnitude of the stimuli that impinge upon their sensory fields, both normally and during ischaemia.

  13. Quantitative detection of myocardial ischaemia by stress echocardiography; a comparison with SPECT

    Directory of Open Access Journals (Sweden)

    Thorsson Ola

    2009-06-01

    Full Text Available Abstract Aims Real-time perfusion (RTP adenosine stress echocardiography (ASE can be used to visually evaluate myocardial ischaemia. The RTP power modulation technique angio-mode (AM, provides images for off-line perfusion quantification using Qontrast® software, generating values of peak signal intensity (A, myocardial blood flow velocity (β and myocardial blood flow (Axβ. By comparing rest and stress values, their respective reserve values (A-r, β-r, Axβ-r are generated. We evaluated myocardial ischaemia by RTP-ASE Qontrast® quantification, compared to visual perfusion evaluation with 99mTc-tetrofosmin single-photon emission computed tomography (SPECT. Methods and Results Patients admitted to SPECT underwent RTP-ASE (SONOS 5500 using AM during Sonovue® infusion, before and throughout adenosine stress, also used for SPECT. Visual myocardial perfusion and wall motion analysis, and Qontrast® quantification, were blindly compared to one another and to SPECT, at different time points off-line. We analyzed 201 coronary territories (left anterior descendent [LAD], left circumflex [LCx] and right coronary [RCA] artery territories in 67 patients. SPECT showed ischaemia in 18 patients and 19 territories. Receiver operator characteristics and kappa values showed significant agreement with SPECT only for β-r and Axβ-r in all segments: area under the curve 0.678 and 0.665; P Conclusion In this agreement study with SPECT, RTP-ASE Qontrast® quantification of myocardial ischaemia was less accurate and less feasible than visual evaluation and needs further development to be clinically useful.

  14. Effect of physical exercise on pain thresholds and plasma beta-endorphins in patients with silent and symptomatic myocardial ischaemia

    OpenAIRE

    Droste, C.; Meyer-Blankenburg, H.; Greenlee, Mark W.; Roskamm, H.

    1988-01-01

    In a double-blind study, eight patients with symptomatic myocardial ischaemia and nine with asymptomatic myocardial ischaemia were compared during physical exercise under naloxone (6 mg i.v.) or placebo. Plasma beta-endorphin, cortisol and catecholamines were measured before exercise, during maximal exercise, and 10, 20 and 60 min after exercise. A tourniquet pain test (on the forearm, under control of transcutaneous PO2), and an electrical pain test (intracutaneous electrode placed in the fi...

  15. Leucocyte depletion attenuates the early increase in myocardial capillary permeability to small hydrophilic solutes following ischaemia and reperfusion

    DEFF Research Database (Denmark)

    Svendsen, Jesper Hastrup; Hansen, P R; Ali, S

    1993-01-01

    The aim was to assess the significance of polymorphonuclear leucocytes on the myocardial capillary permeability to a small hydrophilic indicator, on the vascular tone of the resistance vessels, and on contractile function following ischaemia and reperfusion.......The aim was to assess the significance of polymorphonuclear leucocytes on the myocardial capillary permeability to a small hydrophilic indicator, on the vascular tone of the resistance vessels, and on contractile function following ischaemia and reperfusion....

  16. Role of ATP sensitive potassium channel in extracellular potassium accumulation and cardiac arrhythmias during myocardial ischaemia.

    Science.gov (United States)

    Billman, G E

    1994-06-01

    Extracellular potassium rises rapidly during myocardial ischaemia, correlating with the onset of ventricular arrhythmias. The extracellular accumulation of potassium can induce abnormalities in both impulse conduction and impulse generation. Inhomogeneities of potassium conductance will elicit regional differences in action potential duration and repolarisation. The resulting spatial dispersion of refractory period will allow for fragmentation of impulse conduction on ensuing beats, the formation of irregular reentrant pathways and ventricular fibrillation. In a similar manner, the spread of injury current from the ischaemic tissue to surrounding normal tissue can trigger extrasystoles (depolarisation induced automaticity). It has been hypothesised that the activation of the ATP sensitive potassium channel contributes significantly to reductions in action potential duration and increases in extracellular potassium accumulation during myocardial ischaemia. ATP sensitive potassium channel antagonists prevent ischaemically induced reductions in action potential duration and the dispersion of refractory period but may induce oscillatory afterpotentials under some conditions (for example, calcium overload). In contrast, potassium channel agonists enhance the dispersion of refractory period ischaemia, which promotes the formation of re-entrant arrhythmias. The pharmacological modulation of the ATP sensitive potassium channels could therefore offer a novel approach for the management of cardiac arrhythmias in patients with ischaemic heart disease. In general, channel antagonists prevent ventricular fibrillation, while high (hypotensive) doses of channel agonists can induce malignant arrhythmias during ischaemia in animal models. However, recent evidence also suggests that potassium channel agonists may promote a better preservation of myocardial mechanical performance during reperfusion while ATP sensitive potassium channel antagonists exacerbate mechanical depression

  17. Transient myocardial ischemia after myocardial infarction

    DEFF Research Database (Denmark)

    Mickley, H

    1995-01-01

    Ambulatory ST-segment monitoring is a relatively new device in the evaluation of myocardial ischemia. The method is unique in allowing us to continuously examine the patient over an extended period of time in a changing environmental milieu. In survivors of acute myocardial infarction the prevale...

  18. Myocardial ischaemia following cocaine and adrenaline exposure in a child during an ophthalmological procedure.

    LENUS (Irish Health Repository)

    McGovern, E

    2015-03-01

    We report a 23-month old girl who presented with bilateral epiphora who underwent bilateral lacrimal probing and syringing, during which a cocaine adrenaline solution was used. Two hours after the procedure she developed acute pulmonary oedema secondary to myocardial ischaemia. The patient was treated with intravenous glyceryltrinitrate and milrinone infusions; cardiac enzymes and left ventricular function normalised over the subsequent 72 hours. Topical administration of cocaine and adrenaline solution may have dangerous systemic cardiac effects and should always be used judiciously.

  19. Detection of regional myocardial ischaemia by a novel 80-electrode body surface Delta map in patients presenting to the emergency department with cardiac-sounding chest pain.

    Science.gov (United States)

    Zeb, Mehmood; Mahmoudi, Michael; Garty, Florence; Bannister, Clare; Reddiar, Richard; Nicholas, Zoe; Crouch, Robert; Heyworth, John; Curzen, Nicholas

    2014-04-01

    Presentation with acute chest pain is common, but the conventional 12-lead ECG has limitations in the detection of regional myocardial ischaemia. The previously described method of the body surface mapping system (BSM) Delta map, derived from an 80-electrode BSM, as well as a novel parameter total ischaemic burden (IB), may offer improved diagnostic sensitivity and specificity in patients with myocardial ischaemia. The feasibility of using the novel BSM Delta map technique, and IB, for transient regional myocardial ischaemia was assessed in comparison with 12-lead ECG in 49 patients presenting to the emergency department (ED) with cardiac-sounding chest pain. The sensitivity and specificity of 12-lead ECG for the diagnosis of acute coronary syndrome (ACS) was 67 and 55%, respectively, positive likelihood ratio (+LR) 1.52 [95% confidence interval (CI) 0.86, 2.70] and negative likelihood ratio (-LR) 0.58 [95% CI 0.30, 1.12]. The sensitivity and specificity of the BSM Delta map for the diagnosis of ACS was 71 and 78%, +LR 3.19 [95% CI 1.31, 7.80], -LR 0.37 [95% CI 0.20, 0.68]. There was a significantly positive correlation between peak troponin-I concentration and IB (r=0.437; Psounding chest pain and suggests that it has promising diagnostic accuracy and has superior sensitivity and specificity to the 12-lead ECG. The novel parameter of IB shows a significant correlation with troponin-I and is a promising tool for describing the extent of ischaemia. The use of the BSM Delta map in the ED setting could improve the diagnosis of clinically important ischaemic heart disease and furthermore presents the result in an intuitive manner, requiring little specialist experience. Further larger scale study is now warranted.

  20. Dexmedetomidine protects from post-myocardial ischaemia reperfusion lung damage in diabetic rats

    Directory of Open Access Journals (Sweden)

    Gülay Kip

    2015-09-01

    Full Text Available Objective: Diabetic complications and lipid peroxidation are known to have a close association. Lipid peroxidation commonly occurs at sites exposed to ischaemia, but distant organs and tissues also get damaged during ischaemia/reperfusion (I/R. Some of these targets are vital organs, such as the lung, liver, and kidney; the lung is the most frequently affected. The aim of our study was to investigate the effects of dexmedetomidine on I/R damage in lung tissue and on the oxidant/anti-oxidant system in diabetic rats. Material and methods: Diabetes was induced with streptozotocin (55 mg/kg in 18 Wistar Albino rats, which were then randomly divided into three groups (diabetes control (DC, diabetes plus ischaemia-reperfusion (DIR, and diabetes plus dexmedetomidine-ischaemia/reperfusion (DIRD after the effects of diabetes were clearly evident. The rats underwent a left thoracotomy and then ischaemia was produced in the myocardium muscle by a left anterior descending artery ligation for 30 min in the DIR and DIRD groups. I/R was performed for 120 min. The DIRD group received a single intraperitoneal dose of dexmedetomidine (100 µg/kg; the DIR group received no dexmedetomidine. Group DC was evaluated as the diabetic control group and also included six rats (C group in which diabetes was not induced. These mice underwent only left thoracotomy and were closed without undergoing myocardial ischaemia. Histopathological changes, activities of catalase (CAT and glutathione-S-transferase anti-oxidant enzymes, and malondialdehyde (MDA levels were evaluated in the lung tissues of all rats. Results: Neutrophil infiltration/aggregation was higher in the DIR group than in the C, DC, and DIRD groups (p=0.001, p=0.013, and p=0.042, respectively. The lung injury score was significantly higher in the DIR group than in the C and DC groups (p<0.0001 and p=0.024, respectively. The levels of MDA were significantly higher in the DIR group than in the C and DIRD groups. CAT

  1. Dexmedetomidine protects from post-myocardial ischaemia reperfusion lung damage in diabetic rats

    Science.gov (United States)

    Kip, Gülay; Çelik, Ali; Bilge, Mustafa; Alkan, Metin; Kiraz, Hasan Ali; Özer, Abdullah; Şıvgın, Volkan; Erdem, Özlem; Arslan, Mustafa; Kavutçu, Mustafa

    2015-01-01

    Objective Diabetic complications and lipid peroxidation are known to have a close association. Lipid peroxidation commonly occurs at sites exposed to ischaemia, but distant organs and tissues also get damaged during ischaemia/reperfusion (I/R). Some of these targets are vital organs, such as the lung, liver, and kidney; the lung is the most frequently affected. The aim of our study was to investigate the effects of dexmedetomidine on I/R damage in lung tissue and on the oxidant/anti-oxidant system in diabetic rats. Material and methods Diabetes was induced with streptozotocin (55 mg/kg) in 18 Wistar Albino rats, which were then randomly divided into three groups (diabetes control (DC), diabetes plus ischaemia-reperfusion (DIR), and diabetes plus dexmedetomidine-ischaemia/reperfusion (DIRD)) after the effects of diabetes were clearly evident. The rats underwent a left thoracotomy and then ischaemia was produced in the myocardium muscle by a left anterior descending artery ligation for 30 min in the DIR and DIRD groups. I/R was performed for 120 min. The DIRD group received a single intraperitoneal dose of dexmedetomidine (100 µg/kg); the DIR group received no dexmedetomidine. Group DC was evaluated as the diabetic control group and also included six rats (C group) in which diabetes was not induced. These mice underwent only left thoracotomy and were closed without undergoing myocardial ischaemia. Histopathological changes, activities of catalase (CAT) and glutathione-S-transferase anti-oxidant enzymes, and malondialdehyde (MDA) levels were evaluated in the lung tissues of all rats. Results Neutrophil infiltration/aggregation was higher in the DIR group than in the C, DC, and DIRD groups (p=0.001, p=0.013, and p=0.042, respectively). The lung injury score was significantly higher in the DIR group than in the C and DC groups (p<0.0001 and p=0.024, respectively). The levels of MDA were significantly higher in the DIR group than in the C and DIRD groups. CAT activity

  2. Impaired fasting glucose in combination with silent myocardial ischaemia is associated with poor prognosis in healthy individuals

    DEFF Research Database (Denmark)

    Intzilakis, T; Mouridsen, Mette Rauhe; Almdal, T P

    2012-01-01

    Aim  As both impaired fasting glucose and silent myocardial ischaemia are risk factors for cardiovascular disease and death, we hypothesized that these risk factors in combination would identify those subjects at the highest risk of adverse events. Methods  Healthy individuals without diabetes (n...

  3. β2-adrenoceptor agonist clenbuterol reduces infarct size and myocardial apoptosis after myocardial ischaemia/reperfusion in anaesthetized rats

    Science.gov (United States)

    Zhang, Qiufang; Xiang, Jizhou; Wang, Xuanbin; Liu, Hui; Hu, Benrong; Feng, Mei; Fu, Qin

    2010-01-01

    Background and purpose: Considerable evidence indicates that the β2-adrenoceptor agonist clenbuterol decreases apoptosis in a rodent model of ischaemic cardiomyopathy. In this study, we investigated the effects of clenbuterol on infarct size caused by myocardial ischaemia/reperfusion (I/R) in anaesthetized rats. Experimental approach: Rats were randomly assigned to the following groups: (i) sham (ii) I/R (iii) clenbuterol + I/R (iv) ICI 118551 + clenbuterol + I/R (v) metoprolol + clenbuterol + I/R (vi) metoprolol + I/R (vii) pertussis toxin + clenbuterol + I/R. Under anaesthesia, left anterior descending coronary artery was occluded for 30 min followed by reperfusion for 2 h. Key results: Compared with the control I/R group,the clenbuterol (0.5 mg·kg−1, i.p.) group had reduced infarct size, improved diastolic function and sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA) activity, increased superoxide dismutase activity, and decreased malondialdehyde (MDA) level and LDH, CK release. Clenbuterol increased the phosphorylation of ERK1/2, which resulted in inhibition of myocardial apoptosis as indicated by the reduction of terminal deoxynucleotidyltransferase end labelling-positive staining, Bax/Bcl-2 mRNA and caspase-3 protein expression. The Gi-protein inhibitor pertussis toxin blocked the clenbuterol-induced improvement in cardiac function and infarct size. Pretreatment with ICI 118551(a selective β2-adrenoceptor antagonist) inhibited the effects of clenbuterol mentioned above. The β1-adrenoceptor agonist metoprolol had similar effects to clenbuterol but failed to reduce MDA and improve SERCA activity. When administered together, metoprolol and clenbuterol did not induce synergistic effects. Conclusions and implications: Clenbuterol pretreatment provides significant cardioprotection against ischaemia/reperfusion injury and this is mediated by the β2-adrenoceptor–Gi-protein signalling. A combination of the β2-adrenoceptor agonist clenbuterol and the

  4. Myocardial Ischaemia, Coronary Atherosclerosis and Pulmonary Pressure Elevation in Antiphospholipid Syndrome Patients.

    Science.gov (United States)

    Padjas, Agnieszka; Płazak, Wojciech; Celińska-Lowenhoff, Magdalena; Mazurek, Adam; Perricone, Carlo; Podolec, Piotr; Musiał, Jacek

    2016-01-01

    Thrombotic events in antiphospholipid syndrome (APS) involve venous and arterial circulation with the possible involvement of coronary or pulmonary microcirculation. To evaluate the influence of antiphospholipid antibodies (aPL) and on myocardial ischaemia assessed by single-photon emission computerized tomography (SPECT), coronary atherosclerosis assessed by multidetector computerized tomography (MDCT) and pulmonary pressure assessed by transthoracic echocardiography (TTE) in patients with primary antiphospholipid syndrome (PAPS). TTE, SPECT (Tc 99m sestamibi) and MDCT-based coronary calcium scoring were performed in 26 consecutive PAPS patients (20 females, 6 males, aged 20-61, mean 39.7) without any signs of other autoimmunological disease and without clinical symptoms of heart disease. Out of 26 patients, TEE showed normal left and right ventricle function in 25 (96.2%) and elevated (≥ 30 mm Hg) right ventricle systolic pressure in 7 (26.9%) patients. SPECT revealed myocardial perfusion defects in 15 (57.7%) patients: exercise-induced in 6 (23.1%) and persistent in 11 (42.3%). MDCT revealed coronary calcifications in 4 (15.4%) patients. The number of plaques ranged from 1 to 11 (median 2), volume 3-201.7 mm³ (median 7), calcium scores 1.3-202.6 (median 5.7). In the group with perfusion defects or coronary calcifications (n = 15), all the patients showed elevated aCL IgG. In most of the relatively young APS patients, without any symptoms of ischemic heart disease, SPECT showed myocardial perfusion defects, and coronary calcifications in 1/6 of them. Right ventricle systolic pressure was elevated in 1/4 of APS patients. These pathologies, well known as cardiovascular risk markers, were associated with elevated levels of the IgG class of both anti-cardiolipin and antiB2 GPI antibodies. Thus, in a high percentage of APS patients, clinically silent myocardial ischaemia, pulmonary pressure elevation and coronary atherosclerosis are present and related to the

  5. Polydatin post-treatment alleviates myocardial ischaemia/reperfusion injury by promoting autophagic flux.

    Science.gov (United States)

    Ling, Yuanna; Chen, Guiming; Deng, Yi; Tang, Huixiong; Ling, Long; Zhou, Xiaoming; Song, Xudong; Yang, Pingzhen; Liu, Yingfeng; Li, Zhiliang; Zhao, Cong; Yang, Yufei; Wang, Xianbao; Kitakaze, Masafumi; Liao, Yulin; Chen, Aihua

    2016-09-01

    Polydatin (PD), a resveratrol (RES) glycoside, has a stronger antioxidative effect than RES. It is known that RES is an autophagic enhancer and exerts a cardioprotective effect against ischaemia/reperfusion (I/R) injury. However, the effect of PD post-treatment on myocardial I/R injury remains unclear. In the present study, we investigated the influences of PD post-treatment on myocardial I/R injury and autophagy. C57BL/6 mice underwent left coronary artery (LCA) occlusion and cultured neonatal rat cardiomyocytes (NRCs) subjected to hypoxia were treated with vehicle or PD during reperfusion or re-oxygenation. We noted that PD enhanced autophagy and decreased apoptosis during I/R or hypoxia/reoxygenation (H/R), and this effect was antagonized by co-treatment with adenovirus carrying short hairpin RNA for Beclin 1 and 3-methyladenine (3-MA), an autophagic inhibitor. Compared with vehicle-treated mice, PD-treated mice had a significantly smaller myocardial infarct size (IS) and a higher left ventricular fractional shortening (LVFS) and ejection fraction (EF), whereas these effects were partly reversed by 3-MA. Furthermore, in the PD-treated NRCs, tandem fluorescent mRFP-GFP-LC3 assay showed abundant clearance of autophagosomes with an enhanced autophagic flux, and co-treatment with Bafilomycin A1 (Baf), a lysosomal inhibitor, indicated that PD promoted the degradation of autolysosome. In addition, PD post-treatment reduced mitochondrial membrane potential and cellular reactive oxygen species (ROS) production in NRCs, and these effects were partially blocked by Baf. These findings indicate that PD post-treatment limits myocardial I/R injury by promoting autophagic flux to clear damaged mitochondria to reduce ROS and cell death. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

  6. The anti-diabetic drug miglitol is protective against anginal ischaemia through a mechanism independent of regional myocardial blood flow in the dog.

    Science.gov (United States)

    Uno, Yoshihiro; Minatoguchi, Shinya; Arai, Masazumi; Wang, Ningyuan; Chen, Xue-Hai; Hashimoto, Kazuaki; Lu, Cuanjiang; Takemura, Genzou; Fujiwara, Hisayoshi

    2005-10-01

    1. In the present study, we attempted to clarify whether the antidiabetic drug miglitol, an alpha-glucosidase inhibitor, has a protective effect against anginal ischaemia. We had reported previously that miglitol reduces myocardial infarct size through inhibition of glycogenolysis during ischaemia in rabbits. However, the effect of miglitol on anginal ischaemia remains unknown. 2. In open-chest beagle dogs with a severely stenosed left anterior descending coronary artery, an epicardial electrode was attached to the surface of the risk area of the left ventricle and a microdialysis probe was implanted into the myocardium to measure ST segment changes and interstitial lactate accumulation. The first episode of anginal ischaemia was induced by atrial pacing and phenylephrine infusion (50-100 microg/min) for 10 min. The second episode of anginal ischaemia was induced 210 min after the first episode. Miglitol (10 mg/kg, i.v.) was administered to the miglitol group (n = 10) 30 min before the second episode of anginal ischaemia, whereas saline was administered to the control group (n = 10). Regional myocardial blood flow was measured using coloured microspheres. 3. There was no significant difference in regional myocardial blood flow in the risk and non-risk areas between the first and second episodes of anginal ischaemia and between the miglitol and control groups. During the first and second episodes of anginal ischaemia, the ST segment was decreased to a similar extent in the control group. Although ST segment depression during the first episode of anginal ischaemia was similar in both groups, ST segment depression during the second episode of anginal ischaemia was significantly attenuated in the miglitol-treated group compared with the control group (1.3 +/- 0.4 vs 2.2 +/- 0.4 mV, respectively). Miglitol significantly attenuated myocardial interstitial lactate accumulation in the risk area. 4. In conclusion, in the present study miglitol improved ST segment depression

  7. Modulation of myocardial injury and collagen deposition following ischaemia-reperfusion by linagliptin and liraglutide, and both together.

    Science.gov (United States)

    Wang, Xianwei; Ding, Zufeng; Yang, Fen; Dai, Yao; Chen, Peng; Theus, Sue; Singh, Sharda; Budhiraja, Madhu; Mehta, Jawahar L

    2016-08-01

    Studies have indicated that dipeptidyl peptidase-4 (DPP-4) inhibitors and glucagon-like peptide-1 (GLP-1) agonists reduce infarct size after myocardial ischaemia. Whether these agents modify cardiac remodelling after ischaemia is unclear. Furthermore, it is not known if combination of the two types of drugs is superior to either agent alone. We investigated the modulatory effect of the DPP-4 inhibitor linagliptin alone, the GLP-1 activator liraglutide alone, or the two agents together on myocardial infarct size, left ventricular contractile function and cardiac remodelling signals after a brief period of left coronary artery (LCA) occlusion. C57BL/6 mice were treated with vehicle, the DPP-4 inhibitor linagliptin, the GLP-1 activator liraglutide, or both agents together for 5 days, and then subjected to LCA occlusion (1 h) and reperfusion (3 h). Ischaemia-reperfusion increased reactive oxygen species (ROS) generation and expression of NADPH oxidase (p47(phox), p22(phox) and gp91(phox) subtypes), collagens, fibronectin and proinflammatory cytokines (interleukin 6, tumour necrosis factor α and monocyte chemoattractant protein-1) in the LCA-supplied regions. Pre-treatment with linagliptin or liraglutide reduced infarct size, protected cardiomyocytes from injury and preserved cardiac contractile function in a similar fashion. It is interesting that profibrotic (collagen deposition) signals were expressed soon after ischaemia-reperfusion. Both linagliptin and liraglutide suppressed ROS generation, NADPH oxidase and proinflammatory signals, and reduced collagen deposition. Addition of linagliptin or liraglutide had no significant additive effect above and beyond that of liraglutide and linagliptin given alone. In conclusion, linagliptin and liraglutide can improve cardiac contractile function and indices of cardiac remodelling, which may be related to their role in inhibition of ROS production and proinflammatory cytokines after ischaemia. © 2016 The Author

  8. The effect of cloricromene, a coumarine derivative, on leukocyte accumulation, myocardial necrosis and TNF-alpha production in myocardial ischaemia-reperfusion injury.

    Science.gov (United States)

    Squadrito, F; Altavilla, D; Zingarelli, B; Ioculano, M; Calapai, G; Campo, G M; Miceli, A; Prosdocimi, M; Caputi, A P

    1993-01-01

    The effects of cloricromene, a coumarine derivative, were studied in an anaesthetized rat model of coronary artery ligation (60 min) followed by reperfusion (60 min; MI/R). Sham operated rats were used as controls (Sham MI/R). Myocardial ischaemia-reperfusion injury produced a marked myocardial injury (necrotic area/area-at-risk = 68 +/- 4%; necrotic area/total area = 48 +/- 3%) high serum creatinphosphokinase activity (Sham MI/R = 29 +/- 8 U/ml; MI/R = 205 +/- 11 U/ml) and elevated myocardial myeloperoxidase activity (investigated as an index of leukocyte adhesion and accumulation), in the area-at-risk (6.3 +/- 0.2 U x 10(-3)/g tissue) and in necrotic area (6.5 +/- 0.5 U x 10(-3)/g tissue). Furthermore, serum TNF-alpha was undetectable during the occlusion period, but upon the release of the coronary artery significantly increased. At the end of reperfusion, macrophage TNF-alpha was also enhanced. The administration of cloricromene (2 mg/kg, 5 minutes after the onset of reperfusion) significantly reduced myocardial injury (necrotic area/area-at-risk 30 +/- 1.3%; necrotic area/total area = 25 +/- 1.5) blunted the increase in serum creatinphosphokinase activity (92 +/- 5 U/ml) and lowered myeloperoxidase activity in area-at-risk (2.5 +/- 0.2 U x 10(-3)/g tissue) and in necrotic area (2.2 +/- 0.3 U x 10(-3)/g tissue) and decreased the serum and macrophage levels of TNF-alpha. These data indicate that cloricromene exerts beneficial effects on myocardial ischaemia/reperfusion injury. Finally, since we measured increased serum levels of TNF-alpha that were blunted by the cloricromene treatment, our data are consistent with an involvement of TNF-alpha in the reperfusion injury induced by myocardial ischaemia.

  9. Low-dose CT coronary angiography for the prediction of myocardial ischaemia

    Energy Technology Data Exchange (ETDEWEB)

    Stolzmann, Paul; Donati, Olivio F.; Scheffel, Hans; Baumueller, Stephan; Leschka, Sebastian; Marincek, Borut; Alkadhi, Hatem [University Hospital Zurich (Switzerland). Institute of Diagnostic Radiology; Azemaj, Naim; Plass, Andre; Gruenenfelder, Juerg [University Hospital Zurich, Clinic for Cardiovascular Surgery, Zurich (Switzerland); Kozerke, Sebastian; Boesiger, Peter [University and ETH Zurich, Institute for Biomedical Engineering, Zurich (Switzerland)

    2010-01-15

    The purpose of this study was to prospectively determine the accuracy of low-dose computed tomography coronary angiography (CTCA) for the diagnosis of functionally relevant coronary artery disease (CAD) using cardiac magnetic resonance (CMR) as a standard of reference. Forty-one consecutive patients (age 64 {+-} 10 years) underwent k-space and time broad-use linear acquisition speed-up technique accelerated CMR (1.5 T) and dual-source CTCA using prospective electrocardiography gating within 1 day. CTCA lesions were analysed and diameter stenoses of more than 50% and more than 75% were compared with CMR findings taken as the reference standard for assessing the functional relevance of CAD. CMR revealed perfusion defects in 21/41 patients (51%). A total of 569 coronary segments were analysed with low-dose CTCA. The image quality of low-dose CTCA was diagnostic in 566/569 segments (99.5%) in 39/41 patients (95%). Low-dose CTCA revealed stenoses of more than 50% in 58/123 coronary arteries (47.2%) in 24/41 patients (59%) and more than 75% stenoses in 46/123 coronary arteries (37.4%) in 23/41 patients (56%). Using a greater than 50% diameter stenosis, low-dose CTCA yielded the following per artery sensitivity, specificity, positive and negative predictive values, and accuracy for the detection of perfusion defects: 89%, 79%, 72%, 92% and 83%, respectively. Low-dose CTCA is reliable for ruling out functionally relevant CAD, but is a poor predictor of myocardial ischaemia. (orig.)

  10. Diagnostic value of combining heart rate recovery and P-wave changes with exercise-induced changes in the ST segments for prediction of myocardial ischaemia.

    Science.gov (United States)

    Koyuncu, Ilhan; Tuluce, Kamil; Tuluce, Selcen Yakar; Koyuncu, Betul; Eyuboglu, Mehmet; Eyopoglu, Mehmet; Gursul, Erdal; Akcay, Filiz Akyildiz; Safak, Ozgen; Ekinci, Mehmet Akif; Ozdogan, Ozhan; Kozan, Omer

    2015-08-01

    In patients admitted to outpatient clinics with chest pain, changes in the ST-segments of electrocardiogram (ECG) readings are the most widely used criteria during treadmill ECG tests to determine myocardial ischaemia, despite its poor accuracy. In this study, we evaluated the benefit of combining elongation of P-wave duration (Pdur) and abnormal heart rate recovery (HRR) parameters in addition to changes in the ST-segments for the detection of myocardial ischaemia with treadmill ECG testing. Patients (n = 369) with chest pain who underwent both a treadmill ECG test and myocardial perfusion scintigraphy (MPS) were enrolled. P-wave duration was measured at rest and at the end of the first minute of the recovery phase and elongation of the P-wave was calculated. Abnormal HRR was defined as the failure of a decreasing HR at the end of the first minute of the recovery phase >10% of the maximum HR reached during treadmill ECG testing. The sensitivity, specificity, positive and negative predictive values, diagnostic accuracy values, and likelihood ratios (LRs) of changes in the ST-segments, P-wave elongation, abnormal HRR, and the combination of these three variables for predicting myocardial ischaemia detected by MPS, were calculated separately-in patients without previous coronary artery disease (CAD) and in those with CAD. Elongation of Pdur by 20 ms or longer and abnormal HRR during treadmill ECG test were more common in patients with reversible perfusion defects in MPS than in those without perfusion defects (both P predictive value, 88.9% positive predictive value, and 70% diagnostic accuracy in 77 patients with previous CAD. The LR+ of the combination of the three variables was 12.27. The addition of elongation of Pdur 20 ms and abnormal HRR to the development of significant changes in the ST-segments detected myocardial ischaemia with 52.7% sensitivity, 98.7% specificity, 89.9% negative predictive value, 90.6% positive predictive value, and 90% diagnostic

  11. Evaluation of the relationship between hyperinsulinaemia and myocardial ischaemia/reperfusion injury in a rat model of depression.

    Science.gov (United States)

    Solskov, Lasse; Løfgren, Bo; Pold, Rasmus; Kristiansen, Steen B; Nielsen, Torsten T; Overstreet, David H; Schmitz, Ole; Bøtker, Hans Erik; Lund, Sten; Wegener, Gregers

    2009-11-09

    Major depression is associated with medical co-morbidity, such as ischaemic heart disease and diabetes, but the underlying pathophysiological mechanisms remain unclear. The FSL (Flinders Sensitive Line) rat is a genetic animal model of depression exhibiting features similar to those of depressed individuals. The aim of the present study was to compare the myocardial responsiveness to I/R (ischaemia/reperfusion) injury and the effects of IPC (ischaemic preconditioning) in hearts from FSL rats using SD (Sprague-Dawley) rats as controls and to characterize differences in glucose metabolism and insulin sensitivity between FSL and SD rats. Hearts were perfused in a Langendorff model and were subjected or not to IPC before 40 min of global ischaemia, followed by 120 min of reperfusion. Myocardial infarct size was found to be significantly larger in the FSL rats than in the SD rats following I/R injury (62.4+/-4.2 compared with 46.9+/-2.9%; P<0.05). IPC reduced the infarct size (P<0.01) and improved haemodynamic function (P<0.01) in both FSL and SD rats. No significant difference was found in blood glucose levels between the two groups measured after 12 h of fasting, but fasting plasma insulin (70.1+/-8.9 compared with 40.9+/-4.7 pmol/l; P<0.05) and the HOMA (homoeostatic model assessment) index (P<0.01) were significantly higher in FSL rats compared with SD rats. In conclusion, FSL rats had larger infarct sizes following I/R injury and were found to be hyperinsulinaemic compared with SD rats, but appeared to have a maintained cardioprotective mechanism against I/R injury, as IPC reduced infarct size in these rats. This animal model may be useful in future studies when examining the mechanisms that contribute to the cardiovascular complications associated with depression.

  12. Myocardial metabolism of 123I-BMIPP during low-flow ischaemia in an experimental model: comparison with myocardial blood flow and 18F-FDG

    International Nuclear Information System (INIS)

    Hosokawa, Ryohei; Nohara, Ryuji; Hirai, Taku; Fujita, Masatoshi; Sasayama, Shigetake; Fujibayashi, Yasuhisa; Magata, Yasuhiro; Tadamura, Eiji; Konishi, Junji

    2001-01-01

    Risk stratification of coronary artery disease may provide a basis for selection of treatment to prevent myocardial events and to assist functional recovery. Iodine-123 (ρ-iodophenyl)-3-R,S-methylpentadecanoic acid ( 123 I-BMIPP) is a radioiodinated fatty acid analogue for single-photon emission tomographic (SPET) imaging, and several reports have demonstrated that the abnormal uptake of 123 I-BMIPP is associated with wall motion abnormality and severe coronary artery stenosis. Clarification of the contribution of fatty acids to myocardial metabolism would be highly valuable in recognising this critical condition. In this study, we investigated the myocardial uptake of 123 I-BMIPP under low-flow ischaemia, and compared it with the uptake of fluorine-18 fluorodeoxyglucose ( 18 F-FDG). Using open chest dogs, the flow of the left anterior descending coronary artery was controlled using a pneumatic occluder in order to maintain a 30%-40% reduction of Doppler flow. 123 I-BMIPP and 18 F-FDG were injected into the left atrium after 90 min of ischaemia (protocols 1 and 3). Canine hearts were excised after 120 min of ischaemia for the measurement of radioactivity. In protocol 2, 123 I-BMIPP alone was injected and hearts were excised 8 min after the injection. A time-course biopsy study was also performed at the same time (protocol 3). Wall thickening was evaluated using a wall tracker module. The uptake of 18 F-FDG increased significantly in the ischaemic region (232%±135% vs non-ischaemic, P 18 F-FDG did not correlate well with the severity of MBF. On the other hand, 123 I-BMIPP uptake decreased gradually (78.9%±23.6%, P 123 I-BMIPP was associated not only with wall motion abnormality but also with the severity of MBF. In the biopsy study (protocol 3), the radioactivity of either 123 I-BMIPP or 18 F-FDG correlated well with the MBF at the time of tracer injection and was similar to post-mortem analysis. It is concluded that 18 F-FDG is a valid tool for identifying

  13. Supra- and Sub-Baseline Phosphocreatine Recovery in Developing Brain after Transient Hypoxia-Ischaemia: Relation to Baseline Energetics, Insult Severity and Outcome

    Science.gov (United States)

    Iwata, Osuke; Iwata, Sachiko; Bainbridge, Alan; De Vita, Enrico; Matsuishi, Toyojiro; Cady, Ernest B.; Robertson, Nicola J.

    2008-01-01

    Following hypoxia-ischaemia (HI), an early biomarker of insult severity is desirable to target neuroprotective therapies to patients most likely to benefit; currently there are no biomarkers within the "latent phase" period before the establishment of secondary energy failure. Brief transient phosphocreatine (PCr) recovery overshoot (measured…

  14. Added prognostic value of ischaemic threshold in radionuclide myocardial perfusion imaging: a common-sense integration of exercise tolerance and ischaemia severity.

    Science.gov (United States)

    Marini, Cecilia; Acampa, Wanda; Bauckneht, Matteo; Daniele, Stefania; Capitanio, Selene; Cantoni, Valeria; Fiz, Francesco; Zampella, Emilia; Dib, Bassam; Assante, Roberta; Bruzzi, Paolo; Sambuceti, Gianmario; Cuocolo, Alberto

    2015-04-01

    Reversible ischaemia at radionuclide myocardial perfusion imaging (MPI) accurately predicts risk of cardiac death and nonfatal myocardial infarction (major adverse cardiac events, MACE). This prognostic penetrance might be empowered by accounting for exercise tolerance as an indirect index of ischaemia severity. The present study aimed to verify this hypothesis integrating imaging assessment of ischaemia severity with exercise maximal rate pressure product (RPP) in a large cohort of patients with suspected or known coronary artery disease (CAD). We analysed 1,502 consecutive patients (1,014 men aged 59 ± 10 years) submitted to exercise stress/rest MPI. To account for exercise tolerance, the summed difference score (SDS) was divided by RPP at tracer injection providing a clinical prognostic index (CPI). Reversible ischaemia was documented in 357 patients (24 %) and was classified by SDS as mild (SDS 2-4) in 180, moderate (SDS 5-7) in 118 and severe (SDS >7) in 59. CPI values of ischaemic patients were clustered into tertiles with lowest and highest values indicating low and high risk, respectively. CPI modified SDS risk prediction in 119/357 (33 %) patients. During a 60-month follow-up, MACE occurred in 68 patients. Kaplan-Meier analysis revealed that CPI significantly improved predictive power for MACE incidence with respect to SDS alone. Multivariate Cox analysis confirmed the additive independent value of CPI-derived information. Integration of ischaemic threshold and ischaemia extension and severity can improve accuracy of exercise MPI in predicting long-term outcome in a large cohort of patients with suspected or known CAD.

  15. Added prognostic value of ischaemic threshold in radionuclide myocardial perfusion imaging: a common-sense integration of exercise tolerance and ischaemia severity

    Energy Technology Data Exchange (ETDEWEB)

    Marini, Cecilia [IRCCS AOU San Martino-National Institute for Cancer Research, CNR Institute of Bioimaging and Molecular Physiology, Section of Genoa c/o Nuclear Medicine, Pad. Sommariva, Genoa (Italy); Acampa, Wanda [National Council of Research, Naples (Italy); Bauckneht, Matteo; Capitanio, Selene; Fiz, Francesco; Dib, Bassam; Sambuceti, Gianmario [University of Genoa, IRCCS-AOU San Martino-National Institute for Cancer Research, Nuclear Medicine, Department of Health Science, Genoa (Italy); Daniele, Stefania; Cantoni, Valeria; Zampella, Emilia; Assante, Roberta; Cuocolo, Alberto [University Federico II, Nuclear Medicine, Naples (Italy); Bruzzi, Paolo [IRCCS AOU San Martino-National Institute for Cancer Research, Epidemiology Unit, Genoa (Italy)

    2015-04-01

    Reversible ischaemia at radionuclide myocardial perfusion imaging (MPI) accurately predicts risk of cardiac death and nonfatal myocardial infarction (major adverse cardiac events, MACE). This prognostic penetrance might be empowered by accounting for exercise tolerance as an indirect index of ischaemia severity. The present study aimed to verify this hypothesis integrating imaging assessment of ischaemia severity with exercise maximal rate pressure product (RPP) in a large cohort of patients with suspected or known coronary artery disease (CAD). We analysed 1,502 consecutive patients (1,014 men aged 59 ± 10 years) submitted to exercise stress/rest MPI. To account for exercise tolerance, the summed difference score (SDS) was divided by RPP at tracer injection providing a clinical prognostic index (CPI). Reversible ischaemia was documented in 357 patients (24 %) and was classified by SDS as mild (SDS 2-4) in 180, moderate (SDS 5-7) in 118 and severe (SDS >7) in 59. CPI values of ischaemic patients were clustered into tertiles with lowest and highest values indicating low and high risk, respectively. CPI modified SDS risk prediction in 119/357 (33 %) patients. During a 60-month follow-up, MACE occurred in 68 patients. Kaplan-Meier analysis revealed that CPI significantly improved predictive power for MACE incidence with respect to SDS alone. Multivariate Cox analysis confirmed the additive independent value of CPI-derived information. Integration of ischaemic threshold and ischaemia extension and severity can improve accuracy of exercise MPI in predicting long-term outcome in a large cohort of patients with suspected or known CAD. (orig.)

  16. Subendocardial versus transmural ischaemia in myocardial perfusion SPECT--a Monte Carlo study

    DEFF Research Database (Denmark)

    Bartosik, Jolanta; El-Ali, Henrik Hussein; Nilsson, Ulf

    2006-01-01

    Myocardial perfusion imaging with single-photon emission computed tomography (SPECT) is useful for the evaluation of patients with known or suspected coronary artery disease. Parameters of interest are the reduction in the blood perfusion (severity) and the lesion volume (extent). The aim...

  17. Non-invasive near-infrared fluorescence imaging of the neutrophil response in a mouse model of transient cerebral ischaemia.

    Science.gov (United States)

    Vaas, Markus; Enzmann, Gaby; Perinat, Therese; Siler, Ulrich; Reichenbach, Janine; Licha, Kai; Kipar, Anja; Rudin, Markus; Engelhardt, Britta; Klohs, Jan

    2017-08-01

    Near-infrared fluorescence (NIRF) imaging enables non-invasive monitoring of molecular and cellular processes in live animals. Here we demonstrate the suitability of NIRF imaging to investigate the neutrophil response in the brain after transient middle cerebral artery occlusion (tMCAO). We established procedures for ex vivo fluorescent labelling of neutrophils without affecting their activation status. Adoptive transfer of labelled neutrophils in C57BL/6 mice before surgery resulted in higher fluorescence intensities over the ischaemic hemisphere in tMCAO mice with NIRF imaging when compared with controls, corroborated by ex vivo detection of labelled neutrophils using fluorescence microscopy. NIRF imaging showed that neutrophils started to accumulate immediately after tMCAO, peaking at 18 h, and were still visible until 48 h after reperfusion. Our data revealed accumulation of neutrophils also in extracranial tissue, indicating damage in the external carotid artery territory in the tMCAO model. Antibody-mediated inhibition of α4-integrins did reduce fluorescence signals at 18 and 24, but not at 48 h after reperfusion, compared with control treatment animals. Antibody treatment reduced cerebral lesion volumes by 19%. In conclusion, the non-invasive nature of NIRF imaging allows studying the dynamics of neutrophil recruitment and its modulation by targeted interventions in the mouse brain after transient experimental cerebral ischaemia.

  18. Exercise myocardial perfusion imaging to evaluate inducible ischaemia in children with Kawasaki disease.

    Science.gov (United States)

    Kashyap, Raghava; Mittal, Bhagwant Rai; Bhattacharya, Anish; Manojkumar, Rohit; Singh, Surjit

    2011-02-01

    Kawasaki disease (KD) is an acute multi-system vasculitis of unknown aetiology, which occurs predominantly in infants and young children. Coronary artery abnormalities may occur in 15-25% of patients who are not treated in the acute phase of the disease with a high dose of intravenous immunoglobulin. Myocardial perfusion imaging is used as a modality to monitor the cardiovascular effects of the disease. The objective of our study was to assess the feasibility and results of exercise myocardial perfusion scintigraphy in children with Kawasaki disease. We performed stress myocardial perfusion imaging in 84 patients suffering from KD. The diagnosis of KD was based on the criteria laid down by the American Heart Association. Myocardial perfusion imaging was performed using either thallium or technetium-99m tetrofosmin. Physical exercise using the Bruce protocol was the most frequent cardiac stressor (74 patients) whereas in few patients (seven patients) dobutamine was used to increase the heart rate. Stress-induced reversible perfusion defects were found only in 12 of the total number of patients. Among these two had coronary artery abnormalities on echocardiography. Four of these patients had achieved adequate heart rate with stress. Two among these patients had a repeat imaging done after 1 year and the perfusion defects showed complete resolution in them. This study thus suggests that reversible perfusion defects are seen in asymptomatic patients with KD and that the presence of perfusion defects may not be associated with echocardiographic demonstration of coronary abnormalities. The treadmill test is a reasonable stress protocol for these patients.

  19. Cerebrovascular endothelin-1 hyper-reactivity is associated with transient receptor potential canonical channels 1 and 6 activation and delayed cerebral hypoperfusion after forebrain ischaemia in rats

    DEFF Research Database (Denmark)

    Johansson, S E; Andersen, X E D R; Hansen, R H

    2015-01-01

    . METHODS: Experimental forebrain ischaemia was induced in Wistar male rats by a two-vessel occlusion model, and the cerebral blood flow was measured by magnetic resonance imaging two days after reperfusion. In vitro vasoreactivity studies, immunofluorescence and quantitative PCR were performed on cerebral...... in the vascular smooth muscle cells was enhanced and correlated with decreased cerebral blood flow two days after forebrain ischaemia. Furthermore, under conditions when voltage-dependent calcium channels were inhibited, endothelin-1-induced cerebrovascular contraction was enhanced and this enhancement...... was presumably mediated by Ca(2+) influx via upregulated transient receptor potential canonical channels 1 and 6. CONCLUSIONS: Our data demonstrates that endothelin-1-mediated influx of extracellular Ca(2+) activates transient receptor potential canonical channels 1 and 6 in cerebral vascular smooth muscle cells...

  20. GlyT1 Inhibitor NFPS Exerts Neuroprotection via GlyR Alpha1 Subunit in the Rat Model of Transient Focal Cerebral Ischaemia and Reperfusion

    Directory of Open Access Journals (Sweden)

    Baosheng Huang

    2016-05-01

    Full Text Available Background/Aims: Glycine is a strychnine-sensitive inhibitory neurotransmitter in the central nervous system (CNS, especially in the spinal cord, brainstem, and retina. The objective of the present study was to investigate the potential neuroprotective effects of GlyT1 inhibitor N [3-(4'-fluorophenyl-3-(4'-phenylphenoxy propyl] sarcosine (NFPS in the rat model of experimental stroke. Methods: In vivo ischaemia was induced by transient middle cerebral artery occlusion (tMCAO. The methods of Western Blotting, Nissl Staining and Morris water maze methods were applied to analyze the anti-ischaemia mechanism. Results: The results showed that high dose of NFPS (H-NFPS significantly reduced infarct volume, neuronal injury and the expression of cleaved caspase-3, enhanced Bcl-2/Bax, and improved spatial learning deficits which were administered three hours after transient middle cerebral artery occlusion (tMCAO induction in rats, while, low dose of NFPS (L-NFPS exacerbated the injury of ischaemia. These findings suggested that low and high dose of NFPS produced opposite effects. Importantly, it was demonstrated that H-NFPS-dependent neuronal protection was inverted by salicylate (Sal, a specific GlyR ɑ1 antagonist. Such effects could probably be attributed to the enhanced glycine level in both synaptic and extrasynaptic clefts and the subsequently altered extrasynaptic GlyRs and their subtypes. Conclusions: These data imply that GlyT1 inhibitor NFPS may be a novel target for clinical treatment of transient focal cerebral ischaemia and reperfusion which are associated with altered GlyR alpha 1 subunits.

  1. [Factors influencing cardiac complications in patients with type-2 diabetes mellitus and silent myocardial ischaemia: five-year follow-up].

    Science.gov (United States)

    Mamcarz, Arturi; Chmielewski, Marek; Braksator, Wojiech; Syska-Sumńska, Joanna; Janiszewski, Maciej; Król, Jarosław; Kuch, Marek; Kuch, Jerzy; Dłuiniewski, Mirosław

    2004-12-01

    Silent myocardial ischaemia (SMI), a common disorder, has been studied by different research groups for the last 25 years. It is known that SMI is more common in patients with type 2 diabetes mellitus (type 2 DM) than in the general population, even though pathological mechanisms responsible for SMI are unclear. The aim of the study was to assess the role of SMI and other conditions in predicting adverse outcome in patients with type 2 DM during five years of follow-up. 67 males with type 2 DM were enrolled into the study group. 55-healthy men were used as a control group (CG). Precise clinical examinations (medical history, physical examination, laboratory tests) were conducted. Coronary risk factors and the level of diabetes control were assessed. Noninvasive cardiological tests: ETT, 24 h ECG and echocardiography were performed. The prevalence of the following complications: ischaemia, unstable angina, myocardial infarction, heart failure, death and need for invasive procedures was recorded for five years. Parameters responsible for the complications were analyzed with the use of univariate logistic regression test; odds ratio was calculated. The silent myocardial ischaemia was found in 32.8% of patients with type 2 DM and in 9.1% men in control group (p < 0.001). The complications were observed in 24% of men with DM and in 16% in control group (NS). It was found that 25 parameters in the studied group and 16 parameters in the control group were statistically significant for the prediction of complications (among analyzed 92 parameters). The most important of them in type 2 DM group are: duration of diabetes (years) OR--1.18 (p < 0.01), fasting glucose (mg/dl) OR--1.017 (p < 0.01), SMI episodes (ETT) OR--4.72 (p < 0.01), diastolic dysfunction (E/A), OR--0.003 (p < 0.02) and left ventricle hypertrophy OR--3.86 (p < 0.05), whereas in CG--SMI episodes, OR--17.72 (p < 0.002). (1) The silent myocardial ischaemia is common in patients with type 2 DM. It was diagnosed

  2. Prognostic risk stratification of myocardial ischaemia evaluated by gated myocardial perfusion SPECT in patients with chronic kidney disease

    Energy Technology Data Exchange (ETDEWEB)

    Hatta, Tsuguru [Ohmihachiman Community Medical Center, Division of Nephrology, Department of Medicine, Shiga (Japan); Nishimura, Shigeyuki [Saitama Medical School Hospital, Division of Cardiology, Saitama (Japan); Nishimura, Tsunehiko [Kyoto Prefectural University of Medicine, Department of Radiology, Graduate School of Medical Science, Kyoto (Japan)

    2009-11-15

    The aim of this study was to identify useful predictors of cardiac events in patients with chronic kidney disease (CKD). Among 4,031 patients identified from the Japanese Assessment of Cardiac Events and Survival Study (J-ACCESS) database with suspected or known ischaemic heart disease, we selected 820 with an estimated glomerular filtration rate (eGFR) of < 60 ml/min per 1.73 m{sup 2}. A total of 75 cardiac events developed among these 820 patients. The incidence of cardiac events was higher in the group with a lower eGFR. Multivariate Cox analysis indicated that age, diabetes mellitus, end-systolic volume, summed stress score (SSS) and eGFR were predictors of cardiac events. Event rates of patients with SSS {>=} 9 were significantly higher in groups with lower eGFR values (< 40 and 40-49 ml/min). The SSS value ({>=} 9) is a reliable predictor of cardiac events and myocardial single photon emission computed tomography has incremental value for predicting cardiac events and survival in CKD. (orig.)

  3. Prognostic risk stratification of myocardial ischaemia evaluated by gated myocardial perfusion SPECT in patients with chronic kidney disease

    International Nuclear Information System (INIS)

    Hatta, Tsuguru; Nishimura, Shigeyuki; Nishimura, Tsunehiko

    2009-01-01

    The aim of this study was to identify useful predictors of cardiac events in patients with chronic kidney disease (CKD). Among 4,031 patients identified from the Japanese Assessment of Cardiac Events and Survival Study (J-ACCESS) database with suspected or known ischaemic heart disease, we selected 820 with an estimated glomerular filtration rate (eGFR) of 2 . A total of 75 cardiac events developed among these 820 patients. The incidence of cardiac events was higher in the group with a lower eGFR. Multivariate Cox analysis indicated that age, diabetes mellitus, end-systolic volume, summed stress score (SSS) and eGFR were predictors of cardiac events. Event rates of patients with SSS ≥ 9 were significantly higher in groups with lower eGFR values (< 40 and 40-49 ml/min). The SSS value (≥ 9) is a reliable predictor of cardiac events and myocardial single photon emission computed tomography has incremental value for predicting cardiac events and survival in CKD. (orig.)

  4. The effect of creatine supplementation on myocardial function, mitochondrial respiration and susceptibility to ischaemia/reperfusion injury in sedentary and exercised rats.

    Science.gov (United States)

    Webster, I; Du Toit, E F; Huisamen, B; Lochner, A

    2012-09-01

    To investigate the effects of dietary creatine supplementation alone and in combination with exercise on basal cardiac function, susceptibility to ischaemia/reperfusion injury and mitochondrial oxidative function. There has been an increase in the use of creatine supplementation among sports enthusiasts, and by clinicians as a therapeutic agent in muscular and neurological diseases. The effects of creatine have been studied extensively in skeletal muscle, but not in the myocardium. Male Wistar rats were swim-trained for 8 weeks, 5 days per week. Hearts were excised and either freeze-clamped for biochemical analysis or perfused on the isolated heart perfusion system to assess function and ischaemia/reperfusion tolerance. Mechanical function was documented in working heart and retrograde mode. The left coronary artery was ligated and infarct size determined. Mitochondrial oxidative capacity was quantified. Aortic output recovery of hearts from the sedentary controls (CSed) was significantly higher than those from creatine-supplemented sedentary (CrSed), creatine-supplemented exercised (CrEx) as well as control exercised (CEx) groups. Ischaemic contracture of hearts from CrEx was significantly higher than that of CSed. There were no differences in infarct size and mitochondrial oxygen consumption. This study suggests that creatine supplementation has no effects on basal cardiac function but reduces myocardial tolerance to ischaemia in hearts from exercise-trained animals, by increasing the ischaemic contracture and decreasing reperfusion aortic output. Exercise training alone also significantly decreased aortic output recovery. However, the exact mechanisms for these adverse myocardial effects are unknown and need further investigation. © 2012 The Authors Acta Physiologica © 2012 Scandinavian Physiological Society.

  5. Circadian variation of transient myocardial ischemia in the early out-of-hospital period after first acute myocardial infarction

    DEFF Research Database (Denmark)

    Mickley, H; Pless, P; Nielsen, J R

    1991-01-01

    Circadian rhythms have been demonstrated in acute myocardial infarction (AMI) and in other clinical cardiac dysfunctions. The purpose of this study was to elucidate whether a circadian pattern of transient myocardial ischemia exists after first AMI. Prospectively, 24-hour ambulatory ST-segment mo...

  6. The opposite effects of nitric oxide donor, S-nitrosoglutathione, on myocardial ischaemia/reperfusion injury in diabetic and non-diabetic mice.

    Science.gov (United States)

    Liu, Yi; Xia, Chenhai; Wang, Rutao; Zhang, Jinglong; Yin, Tao; Ma, Yanzuo; Tao, Ling

    2017-08-01

    Nitric oxide is a potent anti-apoptotic and cardioprotective molecule in healthy animals. However, recent study demonstrates that overexpression of eNOS exacerbates the liver injury in diabetic animals. whether diabetes may also alter NO's biologic activity in ischaemic/reperfused heart remains unknown. The present experiment was designed to determine whether the nitric oxide donor, S-nitrosoglutathione, may exert different effects on diabetic and non-diabetic myocardial ischaemia/reperfusion (MI/R) injury. Diabetic state was induced in mice by multiple intraperitoneal injections of low-dose streptozotocin (STZ). The control or diabetic mice were subjected to 30 minutes ischaemia and 3 or 24 hours reperfusion. At 10 minutes before reperfusion, diabetic and non-diabetic mice were received an intraperitoneal injection of S-nitrosoglutathione (GSNO, a nitric oxide donor, 1 μmol/kg). GSNO attenuated MI/R injury in non-diabetic mice, as measured by improved cardiac function, reduced infarct size and decreased cardiomyocyte apoptosis. In contrast, GSNO failed to attenuate but, rather, aggravated the MI/R injury in diabetic mice. Mechanically, the diabetic heart exhibited an increased nitrative/oxidative stress level, as measured by peroxynitrite formation, compared with non-diabetic mice. Co-administration of GSNO with EUK134 (a peroxynitrite scavenger) or MnTE-2-PyP5 (a superoxide dismutase mimetic) or Apocynin (a NADPH oxidase inhibitor) 10 minutes before reperfusion significantly decreased the MI/R-induced peroxynitrite formation and the MI/R injury. Collectively, the present study for the first time demonstrated that diabetes may cause superoxide overproduction, increase NO inactivation and peroxynitrite formation, and thus convert GSNO from a cardioprotective molecule to a cardiotoxic molecule. © 2017 John Wiley & Sons Australia, Ltd.

  7. Effects of enflurane, isoflurane, sevoflurane and desflurane on reperfusion injury after regional myocardial ischaemia in the rabbit heart in vivo

    NARCIS (Netherlands)

    Preckel, B.; Schlack, W.; Comfère, T.; Obal, D.; Barthel, H.; Thämer, V.

    1998-01-01

    It is known that volatile anaesthetics protect myocardial tissue against ischaemic and reperfusion injury in vitro. In this investigation, we have determined the effects of the inhalation anaesthetics, enflurane, isoflurane, sevoflurane and desflurane, administered only during early reperfusion, on

  8. An attempt of thallium-201 myocardial perfusion imaging during transient coronary arterial occlusion by PTCA

    International Nuclear Information System (INIS)

    Nakagawa, Tatsuya; Sugihara, Hiroki; Katahira, Toshio

    1989-01-01

    To evaluate the myocardial perfusion during transient coronary occlusion, we attempted to obtain the myocardial scintigraphy during percutaneous transluminal coronary angioplasty (PTCA). Tl-201 was injected at the last inflation of angioplastic balloon and occlusion was kept on for 60 sec. Planar images or SPECT were obtained immediately after PTCA. With this protocol, myocardial perfusion defects were observed during PTCA and fully redistributed 3 hours after Tl injection. Extent of ischemic lesions were almost same as that observed during exercise in two cases without collateral vessels. In a case with well visualized collateral vessels, perfusion defect was smaller in PTCA images than that in exercise stressed images. We conclude that intravenous injection of Tl-201 during PTCA is useful to assess the alteration of myocardial perfusion due to transient coronary occlusion without increasing the risk of angioplastic procedure. (author)

  9. The diagnostic performance of CT-derived fractional flow reserve for evaluation of myocardial ischaemia confirmed by invasive fractional flow reserve: a meta-analysis

    International Nuclear Information System (INIS)

    Li, S.; Tang, X.; Peng, L.; Luo, Y.; Dong, R.; Liu, J.

    2015-01-01

    Aim: To review the literature on the diagnostic accuracy of CT-derived fractional flow reserve (FFR CT ) for the evaluation of myocardial ischaemia in patients with suspected or known coronary artery disease, with invasive fractional flow reserve (FFR) as the reference standard. Materials and methods: A PubMed, EMBASE, and Cochrane cross-search was performed. The pooled diagnostic accuracy of FFR CT , with FFR as the reference standard, was primarily analysed, and then compared with that of CT angiography (CTA). The thresholds to diagnose ischaemia were FFR ≤0.80 or CTA ≥50% stenosis. Data extraction, synthesis, and statistical analysis were performed by standard meta-analysis methods. Results: Three multicentre studies (NXT Trial, DISCOVER-FLOW study and DeFACTO study) were included, examining 609 patients and 1050 vessels. The pooled sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR+), negative likelihood ratio (LR−), and diagnostic odds ratio (DOR) for FFR CT were 89% (85–93%), 71% (65–75%), 70% (65–75%), 90% (85–93%), 3.31 (1.79–6.14), 0.16 (0.11–0.23), and 21.21 (9.15–49.15) at the patient-level, and 83% (78–63%), 78% (75–81%), 61% (56–65%), 92% (89–90%), 4.02 (1.84–8.80), 0.22 (0.13–0.35), and 19.15 (5.73–63.93) at the vessel-level. At per-patient analysis, FFR CT has similar sensitivity but improved specificity, PPV, NPV, LR+, LR−, and DOR versus those of CTA. At per-vessel analysis, FFR CT had a slightly lower sensitivity, similar NPV, but improved specificity, PPV, LR+, LR−, and DOR compared with those of CTA. The area under the summary receiver operating characteristic curves for FFR CT was 0.8909 at patient-level and 0.8865 at vessel-level, versus 0.7402 for CTA at patient-level. Conclusions: FFR CT , which was associated with improved diagnostic accuracy versus CTA, is a viable alternative to FFR for detecting coronary ischaemic lesions

  10. Serial Holter ST-segment monitoring after first acute myocardial infarction. Prevalence, variability, and long-term prognostic importance of transient myocardial ischemia

    DEFF Research Database (Denmark)

    Mickley, H; Nielsen, J R; Berning, J

    1998-01-01

    Based on serial Holter monitoring performed 7 times within 3 years after a first acute myocardial infarction, we assessed the prevalence, variability and long-term clinical importance of transient myocardial ischemia (TMI) defined as episodes of ambulatory ST-segment depression. In all, 121...... consecutive male patients 7 Holter recordings. Considerable variability was found within and between patients...

  11. Cardiac biomarkers in neonatal hypoxic ischaemia.

    LENUS (Irish Health Repository)

    Sweetman, D

    2012-04-01

    Following a perinatal hypoxic-ischaemic insult, term infants commonly develop cardiovascular dysfunction. Troponin-T, troponin-I and brain natriuretic peptide are sensitive indicators of myocardial compromise. The long-term effects of cardiovascular dysfunction on neurodevelopmental outcome following perinatal hypoxic ischaemia remain controversial. Follow-up studies are warranted to ensure optimal cardiac function in adulthood. CONCLUSION: Cardiac biomarkers may improve the diagnosis of myocardial injury, help guide management, estimate mortality risk and may also aid in longterm neurodevelopmental outcome prediction following neonatal hypoxic-ischaemia.

  12. Survival results of postoperative coronary angiogram for treatment of perioperative myocardial ischaemia following coronary artery bypass grafting: a single-centre experience.

    Science.gov (United States)

    Preußer, Maximilian J; Landwehrt, Jan; Mastrobuoni, Stefano; Biancari, Fausto; Dakkak, Abdul R; Alshakaki, Mosab; Martens, Sven; Dell'Aquila, Angelo M

    2018-02-01

    Although perioperative myocardial ischaemia (PMI) is a well-known complication following coronary artery bypass grafting (CABG), standard strategies for its diagnosis and treatment are so far not defined. In this study, we sought to evaluate the impact on survival of postoperative coronary angiogram for management of patients with PMI after CABG. Overall, 4028 patients underwent isolated CABG in a single-centre institution between January 2006 and September 2013. A total of 168 (4.2%) patients received postoperative coronary angiogram because of diagnosis of PMI. These patients were matched on the basis of gender, age at surgery and date of surgery, with 336 (1:2 ratio) CABG patients without PMI to determine the impact of the PMI management. A total of 476 grafts were examined (263 venous grafts, 196 internal mammary artery grafts and 17 radial artery grafts). Almost three-quarters of the 168 PMI (74.4%) patients underwent postoperative coronary angiogram within 24 h of surgery. Normal postoperative coronary angiogram, graft failure and new native vessels occlusion were observed in 23.2%, 52.4% and 24.4% of patients, respectively. A total of 30 (17.9%) patients underwent surgical revision of grafts, whereas 60 (35.7%) patients were treated with percutaneous coronary intervention. Eighteen (10.7%) PMI patients died during the hospital stay compared with 6 (1.8%) patients in the non-PMI group. Survival rates at 7 years were 62.5% in the PMI group and 81.1% in non-PMI group (P PMI (P 24 h after surgery) was an independent predictor of poorer mid-term survival (P = 0.008; hazard ratio 3.62, 95% confidence interval 1.41-9.33). PMI after CABG is associated with a significantly poorer survival. A prompt postoperative management must always be considered. Further prospective studies are required to confirm our results. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights

  13. Medium intensity oral anticoagulants versus aspirin after cerebral ischaemia of arterial origin (ESPRIT): a randomised controlled trial

    NARCIS (Netherlands)

    Halkes, P. H. A.; van Gijn, J.; Kappelle, L. J.; Koudstaal, P. J.; Algra, A.; Banga, J. D.; Boiten, J.; van der Bom, J. G.; Boon, A. E.; Dippel, D. W. J.; Donders, R. C. J. M.; Eefting, F. D.; Franke, C. L.; Frenken, C. W. G. M.; Frijns, C. J. M.; van Gemert, H. M. A.; de Jaegere, P. P. Th; Kamp, O.; Kwa, V. I. H.; de Leeuw, F.-E.; Linn, F. H. H.; van der Meer, W. K.; Mosterd, A.; Pop, G. A. M.; Raaymakers, T. W. M.; van Schooneveld, M. J.; Stam, J.; Verheugt, F. W. A.; van der Worp, H. B.; Zijlstra, F.; Boekweit, M. P.; van Buuren, M.; Greebe, P.; Mooibroek, G. E.; Slabbers, D. C. V.; Beijer, I. S.; van den Bergh, W. M.; Biessels, G. J.; de Schryver, E. L. L. M.; van Dijk, G. W.; Dorhout-Mees, S. M.; Ferrier, C. H.; Gorter, J. W.; Hofmeijer, J.; Hop, J. W.; Klijn, C. J. M.; Manschot, S. M.; Nieuwkamp, D. J.; van Oers, C. A. M.; Pruissen, D. M. O.; Ruigrok, Y. M.; Schaafsma, J. D.; Slooter, A. J.; Tjeerdsma, H. C.; Wermer, M. J.; van Wijk, I.; Collins, R.; Donnan, G. A.; Rosendaal, F. R.; Vermeulen, M.; Warlow, C. P.; Wheatly, K.; Aichner, F.; Bogousslavsky, J.; Chamorro, A.; Chen, C. P. L. H.; Ferro, J. M.; Hankey, G. J.; Hertzberger, L. I.; Leys, D.; Ricci, S.; Ringelstein, E. B.; Vanhooren, G.; Venables, G. S.; Fazekas, F.; Kleinert, G.; Depondt, C.; Derijck, O.; Dobbelaere, K.; Foncke, E.; Simons, P.; Verhoeven, K.; Girot, M.; Henon, H.; Lucas, C.; Arquizan, C.; Calvet, D.; Mas, J. L.; Decavel, D.; Schilling, M.; Muhs, A.; Postert, T.; Caso, V.; Paciaroni, M.; Grazia Celani, M.; Righetti, E.; Guccione, A.; Sterzi, R.; Cenciarelli, S.; Girelli, L.; Aisa, G.; Freddo, M.; Polidori, M. C.; Cavallini, A.; Marcheselli, S.; Micieli, G.; Rimondi, B.; Landini, G.; Gandolfo, C.; Nanninga-van den Neste, V. M. H.; Bakker, S. L. M.; van Kooten, F.; Berntsen, P. J. I. M.; Feenstra, B.; den Hartog, G. W. A.; Boon, A. M.; Doelman, J. C.; Lieuwens, W. H. G.; Sips, H. J. W. A.; Visscher, F.; Brouwers, P. J. A. M.; Nihom, J.; Poels, P. J. E.; Prick, J. J. W.; Koehler, P. J. J.; Jöbsis, G. J.; van der Sande, J. J.; ten Houten, R.; Veering, M. M.; Bernsen, P. L. J. A.; Boringa, J. B.; van der Meulen, W. D. M.; Tans, J. Th J.; Wagner, G. L.; Blankenvoort, J. B.; Christiaans, M. H.; Kuiper, H.; Mallo, G. N.; Keyser, A. J. M.; Klaver, M. M.; Bouwsma, C.; Kienstra, G. E. M.; Rutgers, A. W. F.; Snoek, J. W.; Bulens, C.; Vermeij, F. H.; Baal, M. G.; van der Steen, A.; van der Wielen-Jongen, J. C. F.; Feikema, W. J.; Lohmann, H. J. M. M.; Sie, L. T. L.; Driesen, J. J. M.; Verhey, J. C. B.; Mulleners, W. M.; Lindeboom, S. F.; Nijmeijer, H. W.; Geervliet, J. P.; Tans, R. J. J.; Verweij, R. D.; Linssen, W. H. J. P.; Vanneste, J. A. L.; Weinstein, H. C.; Zijlmans, J. C. M.; Sie, T. H.; Bertelsmann, F. W.; Lanting, P.; Herderschêe, D.; Leyten, Q. H.; Heerema, J.; Saxena, R.; Böttger, H. R. F.; Driessen-Kletter, M. F.; Alting van Geusau, R. B.; Glimmerveen, W. F.; Henriques, I.; Rebocho, L.; Calado, S.; Viana Baptista, M.; Grilo Goncalves, J. A.; Canhao, P.; Obach, V.; Vila, N.; Hambraeus, J.; Nilsson, S. A.; Nordmark, O.; Terent, A.; Devuyst, G.; Michel, P.; Vuadens, Ph; Mehrzad, A.; Curless, R.; Kalra, L.; Perez, I.; Bates, D.; Cartledge, N.; Dorman, P.; Rodgers, H.; Lees, K. R.; Watt, M.; Enevoldson, P.; Humphrey, P.; Brown, M. M.; Coward, L.; Featherstone, R.; Werring, D.; Young, G.; Bath, P.; Weaver, C.; Dennis, M.; Lindley, R.; Jenkins, C.; Overstall, P. W.; Potter, J.; Eames, P.; Zhang, W. W.; Chang, H. M.; Wong, M. C.; Verro, P.

    2007-01-01

    BACKGROUND: Oral anticoagulants are better than aspirin for secondary prevention after myocardial infarction and after cerebral ischaemia in combination with non-rheumatic atrial fibrillation. The European/Australasian Stroke Prevention in Reversible Ischaemia Trial (ESPRIT) aimed to determine

  14. Medium intensity oral anticoagulants versus aspirin after cerebral ischaemia of arterial origin (ESPRIT) : a randomised controlled trial

    NARCIS (Netherlands)

    Halkes, P H A; van Gijn, J; Kappelle, L J; Algra, A; Koudstaal, P J

    BACKGROUND: Oral anticoagulants are better than aspirin for secondary prevention after myocardial infarction and after cerebral ischaemia in combination with non-rheumatic atrial fibrillation. The European/Australasian Stroke Prevention in Reversible Ischaemia Trial (ESPRIT) aimed to determine

  15. Transient Receptor Potential Vanilloid 2 Regulates Myocardial Response to Exercise.

    Directory of Open Access Journals (Sweden)

    Mindi Naticchioni

    Full Text Available The myocardial response to exercise is an adaptive mechanism that permits the heart to maintain cardiac output via improved cardiac function and development of hypertrophy. There are many overlapping mechanisms via which this occurs with calcium handling being a crucial component of this process. Our laboratory has previously found that the stretch sensitive TRPV2 channels are active regulators of calcium handling and cardiac function under baseline conditions based on our observations that TRPV2-KO mice have impaired cardiac function at baseline. The focus of this study was to determine the cardiac function of TRPV2-KO mice under exercise conditions. We measured skeletal muscle at baseline in WT and TRPV2-KO mice and subjected them to various exercise protocols and measured the cardiac response using echocardiography and molecular markers. Our results demonstrate that the TRPV2-KO mouse did not tolerate forced exercise although they became increasingly exercise tolerant with voluntary exercise. This occurs as the cardiac function deteriorates further with exercise. Thus, our conclusion is that TRPV2-KO mice have impaired cardiac functional response to exercise.

  16. A case of transient left ventricular apical ballooning. A condition simulating an acute myocardial infarction.

    Science.gov (United States)

    Morandi, Fabrizio; Bartesaghi, Giorgio; Romano, Melania; Albonico, Patrizia; Provasoli, Stefano; Salerno-Uriarte, Jorge A

    2004-10-01

    Transient left ventricular apical ballooning, sometimes associated with intraventricular pressure gradient, is a condition simulating an acute myocardial infarction and may occur in patients presenting with chest pain, electrocardiographic changes and minimal myocardial enzyme release typically without coronary angiographic stenosis. It was originally described in the Japanese population and is often associated with cerebrovascular accidents, surgical procedures and emotional and physical stress. We report the case of a 65-year-old woman presenting with chest pain typical of myocardial ischemia, dyspnea, electrocardiographic abnormalities and signs of hemodynamic instability, occurring after a severe emotional stress. Echocardiography and contrast ventriculography showed normokinesis confined to the basal segments of the left ventricle, with a markedly decreased ejection fraction. Scintigraphy was suggestive of a large perfusion defect. The electrocardiographic abnormalities and dyskinesis persisted for many hours. Coronary angiography, performed in the acute phase, was completely normal. Five months later, the functional and electrocardiographic abnormalities had totally disappeared.

  17. Acetate transiently inhibits myocardial contraction by increasing mitochondrial calcium uptake.

    Science.gov (United States)

    Schooley, James F; Namboodiri, Aryan M A; Cox, Rachel T; Bünger, Rolf; Flagg, Thomas P

    2014-12-09

    There is a close relationship between cardiovascular disease and cardiac energy metabolism, and we have previously demonstrated that palmitate inhibits myocyte contraction by increasing Kv channel activity and decreasing the action potential duration. Glucose and long chain fatty acids are the major fuel sources supporting cardiac function; however, cardiac myocytes can utilize a variety of substrates for energy generation, and previous studies demonstrate the acetate is rapidly taken up and oxidized by the heart. In this study, we tested the effects of acetate on contractile function of isolated mouse ventricular myocytes. Acute exposure of myocytes to 10 mM sodium acetate caused a marked, but transient, decrease in systolic sarcomere shortening (1.49 ± 0.20% vs. 5.58 ± 0.49% in control), accompanied by a significant increase in diastolic sarcomere length (1.81 ± 0.01 μm vs. 1.77 ± 0.01 μm in control), with a near linear dose response in the 1-10 mM range. Unlike palmitate, acetate caused no change in action potential duration; however, acetate markedly increased mitochondrial Ca(2+) uptake. Moreover, pretreatment of cells with the mitochondrial Ca(2+) uptake blocker, Ru-360 (10 μM), markedly suppressed the effect of acetate on contraction. Lehninger and others have previously demonstrated that the anions of weak aliphatic acids such as acetate stimulate Ca(2+) uptake in isolated mitochondria. Here we show that this effect of acetate appears to extend to isolated cardiac myocytes where it transiently modulates cell contraction.

  18. Thallium-201 myocardial perfusion imaging during transient coronary occlusion at the time of PTCA

    International Nuclear Information System (INIS)

    Nakagawa, Tatsuya; Sugihara, Hiroki; Inagaki, Suetsugu

    1989-01-01

    To evaluate myocardial perfusion during transient coronary arterial occlusion, thallium-201 was administered intravenously during percutaneous transluminall coronary angioplasty (PTCA) in 12 patients with effort angina, and the resulting perfusion images were compared with those of exercise stress obtained before PTCA. Thallium-201 was injected at the last inflation of an angioplastic baloon and occlusion was maintained for 60 to 90 sec. Three projections of planar images were obtained immediately after PTCA, using a portable gamma camera in an angiography room. These perfusion images obtained during PTCA and exercise were visually interpreted and compared. Myocardial perfusion defects due to the responsible vessel occlusion were observed at early imaging after PTCA, and were fully redistributed three hrs post injection. In 10 patients without angiographically imaged collateral vessels, there were no significatn differences in perfusion between images during PTCA and during exercise. Two patients whose collaterals were observed during coronary angiography before PTCA had higher perfusion scores during PTCA than during exercise. We concluded that intravenous injection of thallium-201 during PTCA is a useful means for assessing alteration of myocardial perfusion due to transient coronary occlusion without increasing the risk of angioplastic procedures, and that it provides more precise information about the jeopardized myocardium, perfused by antegrade blood flow. (author)

  19. Variation in heart rate influences the assessment of transient ischemic dilation in myocardial perfusion scintigraphy

    International Nuclear Information System (INIS)

    Leslie, William D; Levin, Daniel P; Demeter, Sandor J

    2007-01-01

    Transient arrhythmias can affect transient ischemic dilation (TID) ratios. This study was initiated to evaluate the frequency and effect of normal heart rate change on TID measures in routine clinical practice. Consecutive patients undergoing stress/rest sestamibi gated myocardial perfusion scintigraphy were studied (N = 407). Heart rate at the time of stress and rest imaging were recorded. TID ratios were analyzed in relation to absolute change in heart rate (stress minus rest) for subjects with normal perfusion and systolic function (Group 1, N = 169) and those with abnormalities in perfusion and/or function (Group 2, N = 238). In Group 1, mean TID ratio was inversely correlated with the change in heart rate (r = -0.47, P < 0.0001). For every increase of 10 BPM in heart rate change, the TID ratio decreased by approximately 0.06 (95% confidence interval 0.04–0.07). In Group 2, multiple linear regression demonstrated that the change in heart rate (beta = -0.25, P < 0.0001) and the summed difference score (beta = 0.36, P < 0.0001) were independent predictors of the TID ratio. Normal variation in heart rate between the stress and rest components of myocardial perfusion scans is common and can influence TID ratios in patients with normal and abnormal cardiac scans

  20. Prevalence and prediction of silent ischaemia in diabetes mellitus: a population-based study

    DEFF Research Database (Denmark)

    May, O; Arildsen, H; Damsgaard, E M

    1997-01-01

    Register. ST-depression of horizontal or descending character of at least 0.1 mV measured 80 ms after the J-point on either exercise ECG or Holter ECG was considered indicative of myocardial ischaemia. Angina pectoris was considered present if the Rose questionnaire was positive, or chest pain...... was registered simultaneously with ECG evidence of ischaemia. Individuals with ischaemia, but without angina pectoris, were defined as persons with silent ischaemia. RESULTS: Seventy-four percent of the invited group were included. The observed prevalence of silent ischaemia in diabetics was 13.5% (95% CI = 8...

  1. Transient denervation of viable myocardium after myocardial infarction does not alter arrhythmia susceptibility.

    Science.gov (United States)

    Parrish, Diana C; Francis Stuart, Samantha D; Olivas, Antoinette; Wang, Lianguo; Nykjaer, Anders; Ripplinger, Crystal M; Habecker, Beth A

    2018-03-01

    Cardiac sympathetic nerves stimulate heart rate and force of contraction. Myocardial infarction (MI) leads to the loss of sympathetic nerves within the heart, and clinical studies have indicated that sympathetic denervation is a risk factor for arrhythmias and cardiac arrest. Two distinct types of denervation have been identified in the mouse heart after MI caused by ischemia-reperfusion: transient denervation of peri-infarct myocardium and sustained denervation of the infarct. Sustained denervation is linked to increased arrhythmia risk, but it is not known whether acute nerve loss in peri-infarct myocardium also contributes to arrhythmia risk. Peri-infarct sympathetic denervation requires the p75 neurotrophin receptor (p75NTR), but removal of p75NTR alters the pattern of sympathetic innervation in the heart and increases spontaneous arrhythmias. Therefore, we targeted the p75NTR coreceptor sortilin and the p75NTR-induced protease tumor necrosis factor-α-converting enzyme/A disintegrin and metalloproteinase domain 17 (TACE/ADAM17) to selectively block peri-infarct denervation. Sympathetic nerve density was quantified using immunohistochemistry for tyrosine hydroxylase. Genetic deletion of sortilin had no effect on the timing or extent of axon degeneration, but inhibition of TACE/ADAM17 with the protease inhibitor marimastat prevented the loss of axons from viable myocardium. We then asked whether retention of nerves in peri-infarct myocardium had an impact on cardiac electrophysiology 3 days after MI using ex vivo optical mapping of transmembrane potential and intracellular Ca 2+ . Preventing acute denervation of viable myocardium after MI did not significantly alter cardiac electrophysiology or Ca 2+ handling, suggesting that transient denervation at this early time point has minimal impact on arrhythmia risk. NEW & NOTEWORTHY Sympathetic denervation after myocardial infarction is a risk factor for arrhythmias. We asked whether transient loss of nerves in viable

  2. [21-year-old patient with myocardial infarct, transient cerebral ischemia and thrombocytopenia].

    Science.gov (United States)

    Rank, A; Lindner, L; Hiller, E

    2003-03-01

    We report on a case of a young female soccer player who first experienced a transient ischemic attack at the age of 21 and then suffered an acute myocardial infarction accompanied by thrombocytopenia 6 months later. The underlying cause was antiphospholipid syndrome. This clinical picture is caused by a very heterogeneous group of antiphospholipid antibodies, which interfere with plasmatic coagulation at various sites and are able to activate thrombocytes, endothelial cells, and monocytes. This leads to a thrombophilic condition with clinical manifestation of recurrent venous thromboses, arterial embolisms, or premature birth or miscarriage. The main therapeutic options are thus anticoagulation, heparins, and aspirin. Steroids are recommended for cases of pronounced thrombocytopenias; if treatment fails, immunosuppressants are also advisable. The antiphospholipid syndrome should be kept in mind especially in cases of young patients with thromboembolic events since the presence of antiphospholipid antibodies can be detected in 10-20% of this patient group and effective therapy after diagnosis lowers the rate of recurrence.

  3. Silent ischaemia and hypertension

    NARCIS (Netherlands)

    Boon, D.; Piek, J. J.; van Montfrans, G. A.

    2000-01-01

    For many years now, silent ischaemia has been recognized as a distinct clinical entity, and its relevance in different patient groups has been established. However, a number of basic questions have not been answered. In explaining the pathophysiology of silent ischaemia, factors affecting both the

  4. Intracoronary and systemic melatonin to patients with acute myocardial infarction

    DEFF Research Database (Denmark)

    Løvland Halladin, Natalie; Busch, Sarah Ekeløf; Jensen, Svend Eggert

    2014-01-01

    Ischaemia-reperfusion injury following acute myocardial infarctions (AMI) is an unavoidable consequence of the primary percutaneous coronary intervention (pPCI) procedure. A pivotal mechanism in ischaemia-reperfusion injury is the production of reactive oxygen species following reperfusion...

  5. Transient ischemic dilation ratio (TID) correlates with HbA1c in patients with diabetes type 2 with proven myocardial ischemia according to exercise myocardial SPECT

    International Nuclear Information System (INIS)

    Adamikova, A.; Rybka, J.; Bakala, J.; Bernatek, J.; Svacina, S.

    2006-01-01

    Abnormal values of the transient ischemic dilation ratio (TID) according to an exercise myocardial single photon emission computed tomography (SPECT) are linked to severe coronary artery disease. The authors investigated the relationship between TID and the levels of vascular cell adhesion molecule (VCAM), intercellular adhesion molecule (ICAM), E-selectin, microalbuminuria, intimamedia thickness and HbA 1c of diabetic subjects. We observed 38 subjects with diabetes type 2 (10 women, 28 men), of average age 56.08±8.24 years, with no past history of cardiovascular disease. All subjects were examined using an exercise myocardial SPECT. Transient ischemic dilation, summed stress score (SSS), summed rest score (SRS) and stress total severity score (STSS) were determined to quantify myocardial ischemia. The average IMT value was 1.05±0.31 mm. The TID value was 1.02±0.154, VCAM 795.24±163.25 mg/l, ICAM 516.55±164.07, E-selectin 63.82±38.89, HbA 1c 7.09±1.68%, microalbuminuria 68.01±55.21 mg/l. When ascertaining the relation of TID to the other factors we used Pearson's correlation at the level of significance p 1c (p=0.035); the other factors did not show any significant correlation. Diabetes and its long term unsatisfactory compensation can be one of the factors which affect left ventricular transient ischemic dilation. (author)

  6. [Silent myocardial ischemia in diabetics].

    Science.gov (United States)

    Zednícek, L; Hrubá, J

    1989-11-01

    The present communication deals with knowledge gained at detecting episodes of silent myocardial ischaemia in a group of diabetics with a positive load ECG test. With the recent advance of new examination methods it becomes evident that the asymptomatic transitional defects of perfusion or myocardial function in patients with ischaemic heart disease are apparently the most frequent ischaemic accidents which the patient experiences during his or her usual daily activity. They are not caused by increased demands on oxygen supply by the myocardium, rather it is the case of decreased oxygen supply due to dynamic changes in arterial blood supply of the myocardium during transient arterial vasoconstriction. These accidents are markedly more frequent in diabetic patients in whom an earlier and more severe development of ischaemic heart disease occurs. Associated are also specific changes in autonomous nerve fibres conducting pain, which shift a number of ischaemic episodes to the asymptomatic form.

  7. Serial Holter ST-segment monitoring after first acute myocardial infarction. Prevalence, variability, and long-term prognostic importance of transient myocardial ischemia

    DEFF Research Database (Denmark)

    Mickley, H; Nielsen, J R; Berning, J

    1998-01-01

    Based on serial Holter monitoring performed 7 times within 3 years after a first acute myocardial infarction, we assessed the prevalence, variability and long-term clinical importance of transient myocardial ischemia (TMI) defined as episodes of ambulatory ST-segment depression. In all, 121...... consecutive male patients Holter recordings varied around 20% ranging between 18 and 27%. Fifty-five of the patients (46%) had TMI on at least 1 of the 7 Holter recordings. Considerable variability was found within and between patients...... for the presence of TMI. No high-risk group for cardiac death, nonfatal reinfarction or coronary revascularization during up to 10 years of follow-up could be identified by the detection of TMI. From these results we conclude that a routine search for TMI on serial Holter monitoring cannot be recommended in male...

  8. Nifedipine for angina and acute myocardial ischemia

    NARCIS (Netherlands)

    P.G. Hugenholtz (Paul); J.W. de Jong (Jan Willem); P.D. Verdouw (Pieter); P.W.J.C. Serruys (Patrick)

    1983-01-01

    textabstractThis paper reviews the mechanisms believed to be responsible for myocardial ischaemia and the mode of action of calcium antagonist drugs. The clinical management of patients with myocardial ischaemia is discussed in the context of current knowledge about patho-physiology and drug action.

  9. Ambulatory ST segment monitoring after myocardial infarction

    DEFF Research Database (Denmark)

    Mickley, H

    1994-01-01

    The prevalence of transient myocardial ischaemia after myocardial infarction seems to be lower than in other subgroups with coronary artery disease. In postinfarction patients, however, a greater proportion of ischaemic episodes are silent. At present there is substantial evidence that transient...... as important reasons for the inconsistent findings. The precise role of ambulatory ST segment monitoring in clinical practice has yet to be established. Direct comparisons with exercise stress testing may not be appropriate for two reasons. Firstly, the main advantage of ambulatory monitoring may...... be that it can be performed early after infarction at the time of maximum risk. Secondly, it can be performed in most patients after infarction, including those recognised as being at high risk who are unable to perform an exercise stress test....

  10. Residual myocardial ischaemia in first non-Q versus Q wave infarction: maximal exercise testing and ambulatory ST-segment monitoring

    DEFF Research Database (Denmark)

    Mickley, H; Pless, P; Nielsen, J R

    1993-01-01

    post-discharge daily activities, more patients with non-Q wave infarction demonstrated transient episodes of ST-segment depression: 28% vs 14% (ns). Furthermore, ischaemic episodes were significantly longer (42.5 +/- 50.1 vs 22.0 +/- 20.6 min; P

  11. Sodium bicarbonate-augmented stress thallium myocardial scintigraphy

    International Nuclear Information System (INIS)

    Sarin, Badal; Chugh, Pradeep Kumar; Kaushal, Dinesh; Soni, Nakse Lal; Sawroop, Kishan; Mondal, Anupam; Bhatnagar, Aseem

    2004-01-01

    It is well known that sodium bicarbonate in pharmacological doses induces transient alkalosis, causing intracellular transport of serum potassium. The aims of this study were (a) to investigate whether, in humans, myocardial thallium-201 uptake can be augmented by pretreatment with a single bolus of sodium bicarbonate at a pharmacological dose, (b) to verify general safety aspects of the intervention and (c) to evaluate the clinical implications of augmentation of 201 Tl uptake, if any. Routine exercise myocardial scintigraphy was performed twice in eight adult volunteers (five normal and three abnormal), once without intervention and the second time (within a week) following intravenous administration of sodium bicarbonate (88 mEq in 50 ml) as a slow bolus 1 h prior to the injection of 201 Tl. Conventional myocardial thallium study was compared with sodium bicarbonate interventional myocardial scintigraphy with respect to myocardial uptake (counts per minute per mCi injected dose), washout patterns in normal and abnormal myocardial segments, and overall clinical interpretation based on planar and single-photon emission tomographic (SPET) images. All patients remained asymptomatic after the intervention. A mean increase of 53% in myocardial uptake of thallium was noted in post-exercise acquisitions after the intervention, confirming uptake of the tracer via the potassium-hydrogen pump and its augmentation by transient alkalosis. The washout pattern remained unchanged. The visual quality of planar and SPET images improved significantly after the intervention. Out of the five abnormal myocardial segments identified in three cases, four showed significant filling-in after the intervention, causing the diagnosis to be upgraded from ''partial scar'' to ''ischaemia'', or from ''ischaemia'' to ''normal''. The overall scan impression changed in two out of three such cases. Sodium bicarbonate augmentation may have significant implications for stress-thallium scintigraphy

  12. Peroxynitrite formed during a transient episode of brain ischaemia increases endothelium-derived hyperpolarization-type dilations in thromboxane/prostaglandin receptor-stimulated rat cerebral arteries.

    Science.gov (United States)

    Onetti, Y; Dantas, A P; Pérez, B; McNeish, A J; Vila, E; Jiménez-Altayó, F

    2017-05-01

    Increased thromboxane A 2 and peroxynitrite are hallmarks of cerebral ischaemia/reperfusion (I/R). Stimulation of thromboxane/prostaglandin receptors (TP) attenuates endothelium-derived hyperpolarization (EDH). We investigated whether EDH-type middle cerebral artery (MCA) relaxations following TP stimulation are altered after I/R and the influence of peroxynitrite. Vascular function was determined by wire myography after TP stimulation with the thromboxane A 2 mimetic 9,11-dideoxy-9α, 11α -methano-epoxy prostaglandin F2α (U46619) in MCA of Sprague Dawley rats subjected to MCA occlusion (90 min)/reperfusion (24 h) or sham operation, and in non-operated (control) rats. Some rats were treated with saline or the peroxynitrite decomposition catalyst 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrinato iron (III) (20 mg kg -1 ). Protein expression was evaluated in MCA and in human microvascular endothelial cells submitted to hypoxia (overnight)/reoxygenation (24 h) (H/R) using immunofluorescence and immunoblotting. In U46619-pre-constricted MCA, EDH-type relaxation by the proteinase-activated receptor 2 agonist serine-leucine-isoleucine-glycine-arginine-leucine-NH 2 (SLIGRL) was greater in I/R than sham rats due to an increased contribution of small-conductance calcium-activated potassium channels (SK C a ), which was confirmed by the enlarged relaxation to the SK C a activator N-cyclohexyl-N-2-(3,5-dimethyl-pyrazol-1-yl)-6-methyl-4-pyrimidinamine. I/R and H/R induced endothelial protein tyrosine nitration and filamentous-actin disruption. In control MCA, either cytochalasin D or peroxynitrite disrupted endothelial filamentous-actin and augmented EDH-type relaxation. Furthermore, peroxynitrite decomposition during I/R prevented the increase in EDH-type responses. Following TP stimulation in MCA, EDH-type relaxation to SLIGRL is greater after I/R due to endothelial filamentous-actin disruption by peroxynitrite, which prevents TP-induced block of SK C a input to EDH

  13. Ischaemia-induced cellular electrical uncoupling and ventricular fibrillation

    NARCIS (Netherlands)

    de Groot, J. R.

    2002-01-01

    Sudden death resulting from ventricular fibrillation (VF) during acute myocardial ischaemia forms an important contribution to mortality associated with infarction. Its temporal distribution is not known, but 30% of mortality occurs within the first 60 minutes. Two distinct phases of arrhythmias

  14. Impact of reversible myocardial ischaemia on nitric oxide and asymmetric dimethylarginine production in patients with high risk for coronary heart disease.

    Science.gov (United States)

    Ilic, Marina Deljanin; Ilic, Stevan; Lazarevic, Gordana; Kocic, Gordana; Pavlovic, Radmila; Stefanovic, Vladisav

    2010-09-01

    The aim of the present study was to assess the impact of reversible myocardial ischemia, provoked by acute physical activity during an exercise stress echocardiography (ESE), on nitric oxide (NOx) and asymmetric dimethylarginine (ADMA) production in patients with high risk for coronary heart disease (CHD). An overall of 45 patients (27 men, 18 women; mean age, 55.87+/-6.39 years), was enrolled in the study and assigned into groups according to sex, CHD risk factors (RF), wall motion score (WMS), and diabetes mellitus (DM). An ESE was performed on an ergocycle, using a standardized protocol. The modified Saville-Griess method was used to determine NOx concentration. Production of ADMA was evaluated by high-performance liquid chromatography with fluorescent detection. A significant increase of NOx was observed in men (PWMS (PWMS, whereas ADMA significantly increased in both sexes (P or =3 RF groups, respectively), presence of DM (PWMS dynamic (PWMS stable and WMS increased groups, respectively). The WMS was significantly higher in the > or =3 RF group (PWMS and its decrease in patients with increased WMS after ESE, compared with the resting condition, as well as a significant increase of ADMA both in patients with stable WMS and those with increased WMS, irrespective of sex and CHD risk. A significant increase of WMS was observed in the > or =3 CHD RF group, in both sexes, with no regard to the presence of DM.

  15. Effects of exercise training on myocardial fatty acid metabolism in rats with depressed cardiac function induced by transient ischemia

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Liguang; Nohara, Ryuji; Hirai, Taku [Kyoto Univ. (Japan). Graduate School of Medicine] (and others)

    2001-06-01

    The effects of exercise training on metabolic and functional recovery after myocardial transient ischemia were investigated in a rat model. Male Wistar Kyoto rats were subjected either to a 30-min left coronary artery occlusion followed by reperfusion or to a sham operation. At 4 weeks after operation, the rats were randomly assigned either to sedentary conditions or to exercise training for 6 weeks. In the ischemic rats, pinhole SPECT (single photon emission computed tomography) imaging with thallium-201 ({sup 201}Tl) and {sup 123}I-({rho}-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP) showed a reduction of both myocardial perfusion and fatty acid metabolism in the risk zone of the left ventricle (LV). The LV was dilated and the ejection fraction was decreased after ischemic injury. The severity score showed a significant decrease on both {sup 201}Tl and BMIPP ({sup 201}Tl, from 19.9{+-}2.7 to 17.0{+-}2.2, p<0.05; BMIPP, from 21.5{+-}2.4 to 18.6{+-}1.9, p<0.05) after exercise training in the ischemic trained rats, but did not change significantly in their sedentary counterparts. Plasma levels of free fatty acids normalized in the ischemic trained rats, but elevated in the ischemic sedentary rats (0.53{+-}0.05 vs 0.73{+-}0.06 mmol/L, p<0.05). Furthermore, the trained rats had a significant increase in LV stroke volume (0.25{+-}0.02 vs 0.21{+-}0.01 ml/beat, p<0.05) and adaptive cardiac hypertrophy. These findings demonstrate that adaptive improvements in myocardial perfusion, fatty-acid metabolism and LV function were induced by exercise training after transient ischemia. (author)

  16. Further insights into blood pressure induced premature beats: Transient depolarizations are associated with fast myocardial deformation upon pressure decline.

    Science.gov (United States)

    Haemers, Peter; Sutherland, George; Cikes, Maja; Jakus, Nina; Holemans, Patricia; Sipido, Karin R; Willems, Rik; Claus, Piet

    2015-11-01

    An acute increase in blood pressure is associated with the occurrence of premature ventricular complexes (PVCs). We aimed to study the timing of these PVCs with respect to afterload-induced changes in myocardial deformation in a controlled, preclinically relevant, novel closed-chest pig model. An acute left ventricular (LV) afterload challenge was induced by partial balloon inflation in the descending aorta, lasting 5-10 heartbeats (8 pigs; 396 inflations). Balloon inflation enhanced the reflected wave (augmentation index 30% ± 8% vs 59% ± 6%; P blood pressure by 35% ± 4%. This challenge resulted in a more abrupt LV pressure decline, which was delayed beyond ventricular repolarization (rate of pressure decline 0.16 ± 0.01 mm Hg/s vs 0.27 ± 0.04 mm Hg/ms; P pressure 1 ± 12 ms vs 36 ± 9 ms; P = .008), during which the velocity of myocardial shortening at the basal septum increased abruptly (ie, postsystolic shortening) (peak strain rate -0.6 ± 0.5 s(-1) vs -2.5 ± 0.8 s(-1); P pressure decline, with increased postsystolic shortening, and not at peak pressure, that PVCs occur (22% of inflations). These PVCs preferentially occurred at the basal and apical segments. In the same regions, monophasic action potentials demonstrated the appearance of delayed afterdepolarization-like transient depolarizations as origin of PVCs. An acute blood pressure increase results in a more abrupt LV pressure decline, which is delayed after ventricular repolarization. This has a profound effect on myocardial mechanics with enhanced postsystolic shortening. Coincidence with induced transient depolarizations and PVCs provides support for the mechanoelectrical origin of pressure-induced premature beats. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  17. Transient metabolic alkalosis during early reperfusion abolishes helium preconditioning against myocardial infarction: restoration of cardioprotection by cyclosporin A in rabbits.

    Science.gov (United States)

    Pagel, Paul S; Krolikowski, John G

    2009-04-01

    Intracellular acidosis during early reperfusion after coronary artery occlusion was recently linked to cardioprotection resulting from myocardial ischemic postconditioning. We tested the hypotheses that transient alkalosis during early reperfusion abolishes helium preconditioning and that the mitochondrial permeability transition pore inhibitor cyclosporin A (CsA) restores the cardioprotective effects of helium during alkalosis in vivo. Rabbits (n = 36) instrumented for hemodynamics measurement were subjected to a 30-min left anterior descending coronary artery occlusion and 3-h reperfusion. The rabbits received 0.9% saline (control) or three cycles of 70% helium-30% oxygen administered for 5 min interspersed with 5 min of an air-oxygen mixture before left anterior descending coronary artery occlusion in the absence or presence of transient alkalosis (pH = 7.5) produced by administration of IV sodium bicarbonate (10 mEq) 2 min before reperfusion. Other rabbits preconditioned with helium received CsA (5 mg/kg) in the presence of alkalosis or CsA alone. Helium reduced myocardial infarct size (25% +/- 4% of left ventricular area at risk; P Alkalosis during early reperfusion did not alter infarct size alone (46% +/- 2%), but this intervention abolished helium-induced cardioprotection (45% +/- 3%). CsA restored reductions in infarct size produced by helium preconditioning in the presence of alkalosis (28% +/- 6%; P alkalosis during early reperfusion abolishes helium preconditioning in rabbits. CsA restored helium-induced cardioprotection during alkalosis, suggesting that helium preconditioning inhibits mitochondrial permeability transition pore formation by maintaining intracellular acidosis during early reperfusion.

  18. Early detection of myocardial ischaemia in the emergency department by rest or exercise 99mTc tracer myocardial SPET in patients with chest pain and non-diagnostic ECG

    International Nuclear Information System (INIS)

    Conti, A.; Paladini, B.; Francois, C.; Grifoni, S.; Berni, G.; Gallini, C.; Costanzo, E.; Ferri, P.; Matteini, M.; Pieroni, C.; Migliorini, A.; Antoniucci, D.

    2001-01-01

    Chest pain (CP) represents a frequent reason for presentation at the emergency department (ED). A large proportion of patients have non-diagnostic ECG on presentation, and in many cases several hours have elapsed since onset of symptoms. Acute rest myocardial scintigraphy (rest SPET) has been shown to have a relevant role in the detection of patients at risk for coronary events, but its sensitivity and negative predictive value are optimal only within the first 3 h following onset of symptoms. In those with delayed presentation, exercise SPET alone, as a screening approach, appears more promising, but its feasibility and diagnostic role in the ED are still unresolved. A total of 231 consecutive patients with a recent-onset (<24 h) first episode of CP had a negative first-line work-up including ECG, troponins, creatine kinase-MB and echocardiography. These patients were considered at low risk for short-term coronary events. Patients were studied with rest SPET if they presented <3 h after onset of CP and exercise SPET if they presented after ≥3 h. The end-points of the study were detection of significant coronary artery disease (CAD) by angiography and major coronary events or cardiac death at 6 months. Eighty patients (35%) underwent rest SPET, while 151 (65%) underwent exercise SPET. Two of the 159 patients with negative SPET had evidence of critical CAD at 6-month follow-up (one patient in the rest SPET group and one in the exercise SPET group; P=NS). Of the 72 patients (31%) with a positive scan, 34 (15%) had documented CAD (16 patients in the rest SPET group and 18 in the exercise SPET group; P=NS). Sensitivity, specificity, accuracy and predictive value were not statistically different between the two groups. In conclusion, the accuracy of exercise SPET in patients with CP and delayed presentation to the ED is comparable to that of validated rest SPET in patients with early presentation. Owing to the high negative predictive value (99%), exercise SPET is

  19. Early detection of myocardial ischaemia in the emergency department by rest or exercise {sup 99m}Tc tracer myocardial SPET in patients with chest pain and non-diagnostic ECG

    Energy Technology Data Exchange (ETDEWEB)

    Conti, A.; Paladini, B.; Francois, C.; Grifoni, S.; Berni, G. [Emergency Dept., Careggi General Hospital, Florence (Italy); Gallini, C.; Costanzo, E.; Ferri, P.; Matteini, M.; Pieroni, C. [Dept. of Nuclear Medicine, Careggi General Hospital, Florence (Italy); Migliorini, A.; Antoniucci, D. [Dept. of Cardiology, Careggi General Hospital, Florence (Italy)

    2001-12-01

    Chest pain (CP) represents a frequent reason for presentation at the emergency department (ED). A large proportion of patients have non-diagnostic ECG on presentation, and in many cases several hours have elapsed since onset of symptoms. Acute rest myocardial scintigraphy (rest SPET) has been shown to have a relevant role in the detection of patients at risk for coronary events, but its sensitivity and negative predictive value are optimal only within the first 3 h following onset of symptoms. In those with delayed presentation, exercise SPET alone, as a screening approach, appears more promising, but its feasibility and diagnostic role in the ED are still unresolved. A total of 231 consecutive patients with a recent-onset (<24 h) first episode of CP had a negative first-line work-up including ECG, troponins, creatine kinase-MB and echocardiography. These patients were considered at low risk for short-term coronary events. Patients were studied with rest SPET if they presented <3 h after onset of CP and exercise SPET if they presented after {>=}3 h. The end-points of the study were detection of significant coronary artery disease (CAD) by angiography and major coronary events or cardiac death at 6 months. Eighty patients (35%) underwent rest SPET, while 151 (65%) underwent exercise SPET. Two of the 159 patients with negative SPET had evidence of critical CAD at 6-month follow-up (one patient in the rest SPET group and one in the exercise SPET group; P=NS). Of the 72 patients (31%) with a positive scan, 34 (15%) had documented CAD (16 patients in the rest SPET group and 18 in the exercise SPET group; P=NS). Sensitivity, specificity, accuracy and predictive value were not statistically different between the two groups. In conclusion, the accuracy of exercise SPET in patients with CP and delayed presentation to the ED is comparable to that of validated rest SPET in patients with early presentation. Owing to the high negative predictive value (99%), exercise SPET is

  20. Transient myocardial ischemia after abrupt withdrawal of antianginal therapy in chronic stable angina

    DEFF Research Database (Denmark)

    Egstrup, K

    1988-01-01

    In 47 patients with chronic stable angina and proven coronary artery disease, abrupt withdrawal of beta-adrenoceptor blocking agents either as monotherapy or in combination with calcium antagonists (group 1, n = 25) was compared with abrupt withdrawal of calcium antagonist monotherapy (group 2, n...... less than 0.05). These results indicate that a rebound increase in ischemic activity (mainly silent) occurs after abrupt withdrawal of beta-receptor blockade in patients with chronic stable angina. This increase in ischemic activity may be caused by increased myocardial oxygen demand....

  1. Ventricular fibrillation and transient arrhythmias after defibrillation in patients with acute myocardial infarction

    NARCIS (Netherlands)

    Geuze, R. H.; Koster, R. W.

    1984-01-01

    Ventricular fibrillation (VF) and transient arrhythmias after defibrillation were analyzed from the recordings of 28 patients containing at least one episode of ventricular fibrillation. An R-on-T extrasystole initiated VF in 60% of the episodes. Other initiating factors were a late premature beat

  2. Tissue Doppler echocardiography reveals impaired cardiac function in patients with reversible ischaemia

    DEFF Research Database (Denmark)

    Hoffmann, Søren; Mogelvang, Rasmus; Sogaard, Peter

    2011-01-01

    AIMS: To determine if echocardiographic tissue Doppler imaging (TDI) performed at rest detects reduced myocardial function in patients with reversible ischaemia. METHODS AND RESULTS: Eighty-four patients with angina pectoris, no previous history of ischaemic heart disease and normal left ventricu......AIMS: To determine if echocardiographic tissue Doppler imaging (TDI) performed at rest detects reduced myocardial function in patients with reversible ischaemia. METHODS AND RESULTS: Eighty-four patients with angina pectoris, no previous history of ischaemic heart disease and normal left...

  3. Reversible ischaemia in hypertrophic cardiomyopathy.

    OpenAIRE

    Thomson, H.; Fong, W.; Stafford, W.; Frenneaux, M.

    1995-01-01

    Atypical and typical chest pains are common symptoms in patients with hypertrophic cardiomyopathy. Some of these chest pains seem to be caused by ischaemia. It is difficult to objectively demonstrate ischaemia in hypertrophic cardiomyopathy. The first line treatment for chest pain considered to be ischaemic in patients with hypertrophic cardiomyopathy is the use of either a beta blocker or calcium blocker. Septal myectomy can be effective in patients with symptoms refractory to conventional t...

  4. Malignant Multivessel Coronary Spasm Complicated by Myocardial Infarction, Transient Complete Heart Block, Ventricular Fibrillation, Cardiogenic Shock and Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Viji S. Thomson

    2014-07-01

    Full Text Available Multivessel coronary spasm resulting to cardiogenic shock and malignant ventricular arrhythmias though rare has been reported in the literature. The disease seems to be more prevalent in Asians. There have been isolated reports of coronary spasm in patients with reactive airway disease. We report the first case of spontaneous multivessel spasm in a male patient with bronchial asthma of Arab ethnicity resulting in acute myocardial infarction complicated by cardiogenic shock, recurrent ventricular arrhythmias, and transient complete heart block. Literature review of similar cases suggests a strong association with bronchial asthma and a more malignant course in patients with reactive airway disease. The role of intracoronary nitroglycerin in proving the diagnosis even in patients in shock on maximal inotropic supports and intra-aortic balloon pump is highlighted and the importance of considering multivessel coronary spasm as a cause for acute coronary syndrome even in patients with conventional risk factors for atherosclerotic coronary artery disease is reinforced in the discussion of this case.

  5. Targeting Pioglitazone Hydrochloride Therapy After Stroke or Transient Ischemic Attack According to Pretreatment Risk for Stroke or Myocardial Infarction.

    Science.gov (United States)

    Kernan, Walter N; Viscoli, Catherine M; Dearborn, Jennifer L; Kent, David M; Conwit, Robin; Fayad, Pierre; Furie, Karen L; Gorman, Mark; Guarino, Peter D; Inzucchi, Silvio E; Stuart, Amber; Young, Lawrence H

    2017-11-01

    There is growing recognition that patients may respond differently to therapy and that the average treatment effect from a clinical trial may not apply equally to all candidates for a therapy. To determine whether, among patients with an ischemic stroke or transient ischemic attack and insulin resistance, those at higher risk for future stroke or myocardial infarction (MI) derive more benefit from the insulin-sensitizing drug pioglitazone hydrochloride compared with patients at lower risk. A secondary analysis was conducted of the Insulin Resistance Intervention After Stroke trial, a double-blind, placebo-controlled trial of pioglitazone for secondary prevention. Patients were enrolled from 179 research sites in 7 countries from February 7, 2005, to January 15, 2013, and were followed up for a mean of 4.1 years through the study's end on July 28, 2015. Eligible participants had a qualifying ischemic stroke or transient ischemic attack within 180 days of entry and insulin resistance without type 1 or type 2 diabetes. Pioglitazone or matching placebo. A Cox proportional hazards regression model was created using baseline features to stratify patients above or below the median risk for stroke or MI within 5 years. Within each stratum, the efficacy of pioglitazone for preventing stroke or MI was calculated. Safety outcomes were death, heart failure, weight gain, and bone fracture. Among 3876 participants (1338 women and 2538 men; mean [SD] age, 63 [11] years), the 5-year risk for stroke or MI was 6.0% in the pioglitazone group among patients at lower baseline risk compared with 7.9% in the placebo group (absolute risk difference, -1.9% [95% CI, -4.4% to 0.6%]). Among patients at higher risk, the risk was 14.7% in the pioglitazone group vs 19.6% for placebo (absolute risk difference, -4.9% [95% CI, -8.6% to 1.2%]). Hazard ratios were similar for patients below or above the median risk (0.77 vs 0.75; P = .92). Pioglitazone increased weight less among patients at

  6. Risk of Stroke/Transient Ischemic Attack or Myocardial Infarction with Herpes Zoster: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Zhang, Yanting; Luo, Ganfeng; Huang, Yuanwei; Yu, Qiuyan; Wang, Li; Li, Ke

    2017-08-01

    Accumulating evidence indicates that herpes zoster (HZ) may increase the risk of stroke/transient ischemic attack (TIA) or myocardial infarction (MI), but the results are inconsistent. We aim to explore the relationship between HZ and risk of stroke/TIA or MI and between herpes zoster ophthalmicus (HZO) and stroke. We estimated the relative risk (RR) and 95% confidence intervals (CIs) with the meta-analysis. Cochran's Q test and Higgins I 2 statistic were used to check for heterogeneity. HZ infection was significantly associated with increased risk of stroke/TIA (RR = 1.30, 95% CI: 1.17-1.46) or MI (RR = 1.18, 95% CI: 1.07-1.30). The risk of stroke after HZO was 1.91 (95% CI 1.32-2.76), higher than that after HZ. Subgroup analyses revealed increased risk of ischemic stroke after HZ infection but not hemorrhagic stroke. The risk of stroke was increased more at 1 month after HZ infection than at 1-3 months, with a gradual reduced risk with time. The risk of stroke after HZ infection was greater with age less than 40 years than 40-59 years and more than 60 years. Risk of stroke with HZ infection was greater without treatment than with treatment and was greater in Asia than Europe and America but did not differ by sex. Our study indicated that HZ infection was associated with increased risk of stroke/TIA or MI, and HZO infection was the most marked risk factor for stroke. Further studies are needed to explore whether zoster vaccination could reduce the risk of stoke/TIA or MI. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  7. Histopathologic changes during mesenteric ischaemia

    African Journals Online (AJOL)

    Cabot R, Kohatsu S. The effects ofischacmia on the electri- cal and contractile activities of the canine small intestines. Am. J. Surg. 1976; 136: 242 —246. Richards W0, Garrard CL, Allos SH, Bradshaw LA, Staton. DJ, Wikswo J. P Jr. Noninvasive diagnosis of mesentcric. ' ischaemia using a SQUID magnetometer. Ann. Surg.

  8. Emerging molecular therapies targeting myocardial infarction-related arrhythmias

    NARCIS (Netherlands)

    Driessen, Helen E.; van Veen, Toon A. B.; Boink, Gerard J. J.

    2017-01-01

    Cardiac disease is the leading cause of death in the developed world. Ventricular arrhythmias associated with myocardial ischaemia and/or infarction are a major contributor to cardiovascular mortality, and require improved prevention and treatment. Drugs, devices, and radiofrequency catheter

  9. Cerebral And Myocardial Infarction In A Patient With Uncorrected ...

    African Journals Online (AJOL)

    embolism. Ischaemia from thrombotic occlusion of vessels supplying major organs may occur. The case is presented of a 17 year old boy with Tetralogy of Fallot (TOF) who developed acute myocardial infarction (AMI) and cerebral infarction ...

  10. S-nitroso human serum albumin reduces ischaemia/reperfusion injury in the pig heart after unprotected warm ischaemia.

    Science.gov (United States)

    Hallström, Seth; Franz, Maximilian; Gasser, Harald; Vodrazka, Martin; Semsroth, Severin; Losert, Udo M; Haisjackl, Markus; Podesser, Bruno K; Malinski, Tadeusz

    2008-02-01

    Uncoupled endothelial nitric oxide synthase (eNOS) is a major contributor to vascular reactive oxygen species generation in ischaemia/reperfusion (I/R) injury. Supplementation of NO by the novel NO donor S-nitroso human serum albumin (S-NO-HSA) may inhibit uncoupling of eNOS (feedback inhibition). Pigs (n = 14; 33.1 +/- 1.7 kg) were continuously monitored for heart rate (HR), mean arterial pressure (MAP), left ventricular systolic pressure (LVSP), and coronary flow (CF). Infusion of either human serum albumin (n = 8; controls) or S-NO-HSA (n = 6) lasted 60 min (0.1 micromol/kg/h) starting 15 min prior to ischaemia. After clamping the aorta under cardiopulmonary bypass (CPB), the hearts underwent 15 min of warm, unprotected ischaemia (37 degrees C). Reperfusion lasted 150 min (30 min under CPB; 15 min weaning; additional 105 min reperfusion). In biopsies from non-ischaemic hearts and myocardial biopsies taken after 150 min of reperfusion, high-energy phosphates were measured and the calcium ionophore-stimulated release of NO, superoxide, and peroxynitrite (ONOO(-)) were monitored with nanosensors. Compared with non-ischaemic hearts, the NO level decreased from 930 +/- 25 to 600 +/- 15 nmol/L (P < 0.001) while the superoxide level increased from 45 +/- 5 to 110 +/- 10 nmol/L (P < 0.001) after ischaemia. S-NO-HSA restored the NO level to 825 +/- 20 nmol/L, shifted favourably the [NO]/[ONOO(-)] balance (a marker of eNOS uncoupling) from 1.36 +/- 0.06 (ischaemia) to 3.59 +/- 0.18, significantly improved CF (65 +/- 10 vs. control, 43 +/- 5 mL/min, P < 0.05), MAP (57 +/- 5 vs. 39 +/- 3 mm Hg, P < 0.01), LVSP (106 +/- 5 vs. 81 +/- 4 mm Hg, P < 0.01) and phosphocreatine (PCr) content (41.5 +/- 7.3 vs. 18.0 +/- 5.6 micromol/g protein; P < 0.01) at 150 min of reperfusion. Long-lasting release of NO by S-NO-HSA prevented uncoupling of eNOS and thereby improved systolic and diastolic function, myocardial perfusion, and the energetic reserve of the heart after I/R injury.

  11. Isquemia miocárdica silenciosa em pacientes submetidos à prostatectomia transuretral: comparação entre anestesia subaracnóidea e peridural Isquemia miocárdica silenciosa en pacientes sometidos a prostatectomia transuretral: comparación entre anestesia subaracnóidea y peridural Silent myocardial ischaemia in patients undergoing transurethral resection of prostate: comparison of spinal versus epidural anaesthesia

    Directory of Open Access Journals (Sweden)

    Parshotam Lal Gautam

    2004-08-01

    la gravidad de isquemia miocárdica silenciosa fue más alta en pacientes con altos contajes de Detsky, hipertensión arterial y anemia. Ningún paciente presentó efectos cardíacos adversos. CONCLUSIONES: El tipo de anestesia no influenció la incidencia de isquemia miocárdica silenciosa.BACKGROUND AND OBJECTIVES: In the recent past, silent myocardial ischaemia has been found to be associated with increased perioperative cardiac morbidity and mortality. As many as 41 % of patients with either known coronary artery disease or with cardiac risk factors, undergoing a non-cardiac surgery, develop perioperative ischaemia. Various authors have compared regional techniques with general Anaesthesia in selected groups but no one has compared the impact of different techniques of centroneuraxial block on incidence and duration of silent myocardial ischaemia. Thus we compared two different techniques of centroneuraxial block (Spinal versus Epidural block in aged patients selected randomly undergoing TURP surgery. We took TURP patients as they belong to geriatric age group and often have silent or apparent coexistent coronary artery disease. Secondly, TURP surgery related volume overload and shivering in these patients lead to further oxygen demand supply mismatch. METHODS: Forty patients undergoing transurethral resection of prostate were monitored for perioperative silent myocardial ischaemia with the aid of a Holder device. Holter monitoring was started 1 hour prior to surgery and then continued during and after surgery the for next 24 hours. Holter data was analyzed using DSM model 300. RESULTS: The overall incidence of silent myocardial ischaemia in our study was 30%. No relationship could be established between silent myocardial ischaemia and type of centroneuraxial block. Most of the episodes of myocardial ischaemia occurred in preoperative period and, these had no correlation with hemodynamic fluctuations. However the incidence and load of silent myocardial ischaemia

  12. Impact of image processing in the detection of ischaemia using CZT-SPECT/CT.

    Science.gov (United States)

    Koopman, Daniëlle; van Dalen, Jorn A; Slump, Cornelis H; Lots, Dimitri; Timmer, Jorik R; Jager, Pieter L

    2015-01-01

    The new multipinhole cardiac single photon emission computed tomography/computed tomography (SPECT/CT) cameras with cadmium-zinc-telluride (CZT) detectors are highly sensitive and produce images of high quality but rely on complex dedicated reconstruction algorithms. The aim of this study was to determine the impact of various processing steps on image formation and in the detection of ischaemia in CZT-SPECT/CT both with and without attenuation correction (AC). Data on 20 consecutive patients who underwent a 1-day protocol stress-rest SPECT/CT using 99mTc-tetrofosmin were processed twice by three experienced operators, yielding 120 AC and 120 noncorrected (NC) data sets. Processing steps included selection and determination of myocardial axes, manual SPECT/CT coregistration for AC and myocardial masking. Using the 17-segment cardiac model, differences between stress and rest segmental uptake (%) were calculated for NC and AC image sets. Both interoperator and intraoperator variations were considered significant for the diagnosis of ischaemia when greater than 5%. The mean interoperator variations were 2.4±1.4% (NC) and 3.8±1.9% (AC) (Pprocessed cases, operator variation was larger than 5% and therefore potentially clinically interfering with the diagnosis of ischaemia. Differences between interoperator and intraoperator variations were nonsignificant. Operator variations in the processing of myocardial perfusion image data using CZT-SPECT/CT are significant and may influence the diagnosis of ischaemia, especially when AC is applied. Clearer guidelines for image processing are necessary to improve the reproducibility of the studies and to obtain a more reliable diagnosis of ischaemia.

  13. Justification for intravenous magnesium therapy in acute myocardial infarction

    DEFF Research Database (Denmark)

    Rasmussen, H S

    1988-01-01

    Recent studies have shown that patients with acute myocardial infarction (AMI) are magnesium-deficient and develop an additional transient decrease in serum magnesium concentrations (S-Mg c) during the acute phase of the infarct. Animal experiments, as well as studies on humans, have indicated...... that the acute decrease in S-Mg c as well as a more chronic magnesium (Mg) deficiency state are harmful to the myocardium in the setting of acute ischaemia. This knowledge has led during the last couple of years to the performance of four double-blind placebo controlled studies in which the effect of i.......v. magnesium therapy on mortality and incidence of arrhythmias in patients with AMI has been evaluated. Magnesium treatment more than halved the acute mortality and incidence of arrhythmias requiring treatment in three of the four intervention studies. The mechanisms behind the beneficial effect of magnesium...

  14. Humanin prevents brain mitochondrial dysfunction in a cardiac ischaemia-reperfusion injury model.

    Science.gov (United States)

    Kumfu, Sirinart; Charununtakorn, Savitree T; Jaiwongkam, Thidarat; Chattipakorn, Nipon; Chattipakorn, Siriporn C

    2016-06-01

    What is the central question of this study? Myocardial ischaemia-reperfusion (I/R) injury causes interference in the systemic circulation and damages not only the heart but also several vital organs, including the brain. Recently, a novel peptide called humanin has been shown to exert potent neuroprotective effects. However, the effect of humanin on the brain during cardiac I/R injury has not yet been investigated. What is the main finding and its importance? The I/R injury caused blood-brain barrier breakdown, increased brain oxidative stress and resulted in mitochondrial dysfunction. Only the humanin treatment before ischaemia attenuated brain mitochondrial dysfunction, but it did not prevent blood-brain barrier breakdown or brain oxidative stress. Humanin treatment during ischaemia and in the reperfusion period provided no neuroprotection. These findings indicate that humanin exerted neuroprotection during cardiac I/R injury via improved brain mitochondrial function. Myocardial ischaemia-reperfusion (I/R) injury causes interference in the systemic circulation and damages not only the heart but also several vital organs, including the brain. Nevertheless, limited information is available regarding the effect of cardiac I/R injury on the brain, including blood-brain barrier (BBB) breakdown, brain oxidative stress and mitochondrial function. Recently, a novel peptide called humanin has been shown to exert potent neuroprotective effects. However, the effect of humanin on the brain during cardiac I/R injury has not yet been investigated. Forty-two male Wistar rats were divided into the following two groups: an I/R group, which was subjected to a 30 min left anterior descending coronary artery occlusion followed by 120 min reperfusion (I/R group; n = 36); and a sham group (n = 6). The I/R group was divided into six subgroups. Each subgroup was given either vehicle or humanin analogue (84 μg kg(-1) , i.v.) at three different time points, namely before

  15. Clinical value of delayed thallium-201 myocardial imaging in suspected acute myocardial infarction.

    Science.gov (United States)

    McKillop, J H; Turner, J G; Gray, H W; Bessent, R G; Greig, W R

    1978-01-01

    Fifty patients with acute chest pain had thallium-201 myocardial imaging performed three to six days after emergency admission to hospital. The image was abnormal in 20 out of 22 patients with acute transmural myocardial infarcts but in only 1 of 5 with acute subendocardial infarcts. Indistinguishable scan abnormalities caused by old infarcts were seen in 7 patients, and caused by myocardial ischaemia in 1 patient. A single thallium-201 myocardial scan some days after the onset of symptoms appears to be of little value in the clinical assessment of patients with suspected acute myocardial infarction. Images PMID:687488

  16. Temporary ischaemia induced by degradable starch microspheres

    International Nuclear Information System (INIS)

    Lote, K.

    1981-01-01

    Possible thrombogenic effects of degradable starch microspheres were investigated. Controlled temporary small intestinal ischaemia was induced by injection into the superior mesenteric artery in cats. Arterial flow consistently recovered after ischaemia. No consumption of blood platelets, fibrinogen, or Factor VIII was observed. Aggregation of human platelets was not influenced by microsphere exposure, and platelet retention in starch microsphere columns was minimal. No thrombosis was detected in feline small intestinal vessels in vivo nor did starch surfaces induce adhesion or aggregation of human platelets in vitro. Thus, no evidence of thrombotic hazards was found by inducing temporary intestinal ischaemia by starch microspheres. (Auth.)

  17. Feasibility of targeting ischaemia-related ventricular arrhythmias by mimicry of endogenous protection by endocannabinoids.

    Science.gov (United States)

    Andrag, Ellen; Curtis, Michael J

    2013-08-01

    The hypothesis that endocannabinoids protect hearts against ventricular fibrillation (VF) induced by myocardial ischaemia and reperfusion was examined, and the concept that cannabinoids may represent a new class of anti-VF drug was tested. In rat isolated hearts (Langendorff perfusion), VF evoked by reperfusion after 60 min regional ischaemia is known to be exacerbated by inhibitors of endogenous protectants such as nitric oxide. This preparation was used to assay the effects of cannabinoid agonists and antagonists, and the protocols were varied to examine mechanisms. Reperfusion-induced VF was not facilitated by relatively selective CB1 (1 μM AM251) or CB2 (1 μM AM630) antagonists. VF evoked during early (30 min) acute ischaemia was also unaffected. However, AM251 significantly increased the incidence of VF and the duration of VF episodes occurring during the later stage of acute ischaemia (30-60 min). AM630 had no such effects. In a separate study, cannabinoid perfusion (anandamide or 2-arachidonoylglycerol, both 0.01-1 μM) failed to reduce VF incidence concentration-dependently during 30 min ischaemia. In all these studies, changes in ancillary variables (QT, PR, heart rate) were unrelated to changes in VF. Endocannabinoids are not endogenous anti-VF mediators during reperfusion, but may have a weak protective effect during the late stages of ischaemia, mediated via CB1 agonism. This does not suggest endocannabinoids are important endogenous protectants in these settings, or that CB1 (or CB2) receptors are useful novel targets for developing drugs for VF. © 2013 The British Pharmacological Society.

  18. Refractory hyperglycaemia induced by glucose-insulin-potassium infusion in acute myocardial infarction

    NARCIS (Netherlands)

    Svilaas, Tone; van der Horst, I.C.C.; Nijsten, M.W.N.; Zijlstra, F.

    2006-01-01

    Background. Recent randomised clinical trials have not confirmed the beneficial effects of glucose-insulin-potassium (GIK) infusion observed in experimental models of myocardial ischaemia and infarction. Methods. We investigated glucose levels and insulin dose in 107 patients treated with

  19. Deleterious Effects of High Dose Connexin 43 Mimetic Peptide Infusion After Cerebral Ischaemia in Near-Term Fetal Sheep

    Directory of Open Access Journals (Sweden)

    Alistair J. Gunn

    2012-05-01

    Full Text Available Hypoxic-ischaemic brain injury at birth is associated with 1–3/1000 cases of moderate to severe encephalopathy. Previously, we have shown that connexin 43 hemichannel blockade, with a specific mimetic peptide, reduced the occurrence of seizures, improved recovery of EEG power and sleep state cycling, and improved cell survival following global cerebral ischaemia. In the present study, we examined the dose response for intracerebroventricular mimetic peptide infusion (50 µmol/kg/h for 1 h, followed by 50 µmol/kg/24 h (low dose or 50 µmol/kg/h for 25 h (high dose or vehicle only (control group, starting 90 min after the end of ischaemia, following global cerebral ischaemia, induced by 30 min bilateral carotid artery occlusion, in near-term fetal sheep (128 ± 1 days gestation. Both peptide infusion groups were associated with a transient significant increase in EEG power between 2–12 h after ischaemia. The ischaemia-low dose group showed a significant recovery of EEG power from day five compared to the ischaemia-vehicle and -high dose groups. In contrast, the high dose infusion was associated with greater secondary increase in impedance (brain cell swelling, as well as a trend towards a greater increase in lactate concentration and mortality. These data suggest that higher doses of connexin mimetic peptide are not beneficial and may be associated with adverse outcomes, most likely attributable to uncoupling of connexin 43 gap junctions leading to dysfunction of the astrocytic syncytium.

  20. [Management of coronary artery disease in diabetic patients with lower limb critical ischaemia: assessment of operational risk, drug therapy and indications for interventions].

    Science.gov (United States)

    Dedov, I I; Kalashnikov, V Iu; Terekhin, S A; Melkozerov, K V

    2012-01-01

    Despite obvious progress in management of diabetes mellitus, the DM-related complications rate remains inadmissibly high. Macroangiopathy is known to rank first amongst complications of diabetes mellitus, and coronary artery disease remains to be the major cause of death. Analysed herein are peculiarities of the clinical course in diabetic patients presenting with coronary artery disease and lower limb critical ischaemia, followed by discussing the issues concerning drug therapy, preoperative examination, and methods of diagnosis in this cohort of patients prior to vascular operations, assessment of the preoperative risk, indications for coronarography and myocardial revascularization. Also presented are the results of the main clinical trials dedicated to preoperative myocardial revascularization, including those in diabetic patients with limb critical ischaemia, and finally highlighting current importance of optimizing approaches to managing and working out algorithms of treatment policy for diabetic patients with a combination of coronary artery disease, diabetes mellitus, and critical limb ischaemia.

  1. Myocardial ischaemia during coronary artery bypass graft surgery: a ...

    African Journals Online (AJOL)

    2012-02-09

    Feb 9, 2012 ... tamponade, diastolic dysfunction, right ventricular dysfunction and intracardiac air may also lead to low cardiac output syndrome.1 The advent of echocardiography promises to revolutionise the management of this syndrome with early diagnosis and resolution of correctable causes. Modulation of the stress ...

  2. Naoxintong attenuates Ischaemia/reperfusion Injury through inhibiting NLRP3 inflammasome activation.

    Science.gov (United States)

    Wang, Yaqiong; Yan, Xiaoxiang; Mi, Shouling; Li, Zhang; Wang, Yuexiang; Zhu, Hong; Sun, Xiaolei; Zhao, Buchang; Zhao, Chao; Zou, Yunzeng; Hu, Kai; Ding, Xiaoqiang; Sun, Aijun; Ge, Junbo

    2017-01-01

    Naoxintong (NXT) is a Chinese Materia Medica standardized product extracted from 16 various kinds of Chinese traditional herbal medicines including Salvia miltiorrhiza, Angelica sinensis, Astragali Radix. Naoxintong is clinically effective in treating ischaemia heart disease. Nucleotide-binding oligomerization domain-Like Receptor with a Pyrin domain 3 (NLRP3) inflammasome has been critically involved in myocardial ischaemia/reperfusion (I/R) injury. Here, we have been suggested that NXT might attenuate myocardial I/R injury via suppression of NLRP3 inflammasome activation. Male C57BL6 mice were subjected to myocardial I/R injury via 45 min. coronary ligation and release for the indicated times. Naoxintong (0.7 g/kg/day) and PBS were orally administrated for 2 weeks before surgery. Cardiac function assessed by echocardiography was significantly improved in the NXT group compared to PBS group at day 2 after myocardial I/R. NLRP3 inflammasome activation is crucially involved in the initial inflammatory response after myocardial I/R injury, leading to cleaved caspase-1, mature interleukin (IL)-1β production, accompanying by macrophage and neutrophil infiltration. The cardioprotective effect of NXT was associated with a diminished NLRP3 inflammasome activation, decreased pro-inflammatory macrophage (M1 macrophages) and neutrophil infiltration after myocardial I/R injury. In addition, serum levels of IL-1β, indicators of NLRP3 inflammasome activation, were also significantly suppressed in the NXT treated group after I/R injury. Naoxintong exerts cardioprotive effects at least partly by suppression of NLRP3 inflammasome activation in this I/R injury model. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  3. Histopathologic changes during mesenteric ischaemia and ...

    African Journals Online (AJOL)

    There was an acute worsening of the pathology during reperfusion, the severity being greater when reperfusion was preceded by longer periods of ischaemia. These changes were statistically significant. The observed pattern in this study shows clearly that reperfusion injury is reflected in the histopathologic response and ...

  4. Isoprostanes--markers of ischaemia reperfusion injury.

    LENUS (Irish Health Repository)

    Sakamoto, H

    2012-02-03

    Ischaemia reperfusion injury is a common and important phenomenon that occurs predictably in patients undergoing such procedures as cardiopulmonary bypass, thrombolysis, surgery under tourniquet, organ transplantation or embolectomy. Oxidative stress and the resulting lipid peroxidation play a major role in reperfusion injury. Membrane and cellular dysfunction result and, subsequently, organ injury or failure may ensue. Traditional methods of quantifying ischaemia reperfusion injury, including measurement of malondialdehyde, lack specificity and sensitivity. It was reported in 1990 that isoprostanes, a series of prostaglandin-like compounds, are produced by the free radical-catalyzed peroxidation of arachidonic acid. Measurement of the isoprostane concentration in urine or plasma provides the most reliable, non-invasive method currently available to assess oxidative stress in vivo. Serial measurement of isoprostanes in biological fluids has enhanced our understanding of the mechanisms underlying ischaemia reperfusion injury itself and its role in certain diseases. Furthermore, measurement of the isoprostane concentration provides a means to assess the effects of prophylactic and therapeutic interventions. In the future, the development of rapid, simple assays for isoprostanes offers the potential to assess prognosis during and after ischaemia reperfusion events.

  5. Prevalence and predictors of an abnormal stress myocardial perfusion study in asymptomatic patients with type 2 diabetes mellitus

    Energy Technology Data Exchange (ETDEWEB)

    Scholte, Arthur J.H.A.; Schuijf, Joanne D.; Wall, Ernst E. van der; Bax, Jeroen J. [Leiden University Medical Center, Department of Cardiology, Albinusdreef 2, PO Box 9600, Leiden (Netherlands); Kharagjitsingh, Antje V. [Medisch Centrum Haaglanden, Department of Internal Medicine, The Hague (Netherlands); Dibbets-Schneider, Petra; Stokkel, Marcel P. [Leiden University Medical Center, Department of Nuclear Medicine, Leiden (Netherlands)

    2009-04-15

    The purpose of this study was to evaluate the prevalence of an abnormal stress myocardial perfusion study in a cohort of truly asymptomatic patients with type 2 diabetes mellitus using myocardial perfusion imaging by means of single photon emission computed tomography (SPECT). Secondly, we determined which clinical characteristics may predict an abnormal stress myocardial perfusion study in this population. A total of 120 asymptomatic patients (mean age 53{+-}10 years) with type 2 diabetes mellitus and one or more risk factors for coronary artery disease were prospectively recruited from an outpatient diabetes clinic. All patients underwent myocardial perfusion imaging by means of adenosine {sup 99m}Tc sestamibi SPECT. Images were evaluated for the presence of perfusion abnormalities as well as other nonperfusion abnormalities that may indicate extensive ischaemia, including left ventricular dysfunction (defined as a left ventricular ejection fraction <45%), transient ischaemic dilatation and adenosine-induced ST segment depression. Multivariable analysis was performed using a backward selection strategy to identify potential predictors for an abnormal stress myocardial perfusion study. Finally, all patients were followed up for 12 months to determine the occurrence of cardiovascular events: (1) cardiac death, (2) nonfatal myocardial infarction, (3) unstable angina requiring hospitalization, (4) revascularization, or (5) stroke. Of the 120 patients, 40 (33%) had an abnormal stress study, including myocardial perfusion abnormalities in 30 patients (25%). In 10 patients (8%), indicators of extensive (possibly balanced ischaemia) were observed in the absence of abnormal perfusion. The multivariable analysis identified current smoking, duration of diabetes and the cholesterol/high-density lipoprotein (HDL) ratio as independent predictors of an abnormal stress study. During a follow-up period of 12 months six patients (5%) had a cardiovascular event. The current study

  6. Effects of permanent dual chamber pacing on myocardial perfusion in symptomatic hypertrophic cardiomyopathy

    NARCIS (Netherlands)

    Posma, JL; Blanksma, PK; VanderWall, EE; Vaalburg, W; Crijns, HJGM; Lie, KI

    1996-01-01

    Objective-Angina and the presence of myocardial ischaemia are common in hypertrophic cardiomyopathy. Dual chamber pacing results in clinical improvement in these patients. This study evaluates the effects of permanent dual chamber pacing on absolute regional myocardial perfusion and perfusion

  7. Serial changes in BMIPP uptake in relation to thallium uptake in the rat myocardium after ischaemia.

    Science.gov (United States)

    Noriyasu, Kazuyuki; Mabuchi, Megumi; Kuge, Yuji; Morita, Koichi; Tsukamoto, Takahiro; Kohya, Tetsuro; Kitabatake, Akira; Tamaki, Nagara

    2003-12-01

    Several clinical studies have shown that iodine-123 labelled 15-(p-iodophenyl)-3-(R, S)-methylpentadecanoic acid (BMIPP) uptake is often lower than the uptake of perfusion tracers in patients with ischaemic heart disease. However, BMIPP accumulation may not decrease during the acute phase of a stunned myocardium in patients with acute coronary syndrome. We evaluated serial changes in BMIPP and perfusion tracer uptake in the myocardium after ischaemia. We performed a 20-min left coronary artery occlusion followed by reperfusion in male Wistar rats. One hour after the reperfusion, echocardiography was performed. Intravenous injection of iodine-125 labelled BMIPP and thallium-201 was performed 1 day (acute group) and 5 days (subacute group) after the operation. To determine the myocardial distribution of 125I-BMIPP and 201Tl, dual-tracer autoradiography was conducted. We identified regions of interest in the anterolateral wall as an area at risk and in the inferoseptum as a remote control area. The anterolateral wall/inferoseptum ratio (A/I ratio) was calculated to compare the distributions of 125I-BMIPP and 201Tl. Coronary occlusion induced hypokinesia in the anterolateral region 1 h after the reperfusion. The A/I ratio of 125I-BMIPP was significantly higher than that of 201Tl in the acute group (1.01 +/- 0.15 vs 0.80 +/- 0.23, Prats showed a significantly lower A/I ratio of 125I-BMIPP than 201Tl in the subacute phase. These data suggest that BMIPP uptake is preserved despite a decrease in perfusion in the acute phase after ischaemia. In the subacute phase, on the other hand, BMIPP uptake is similar to or even lower than thallium uptake. Since BMIPP uptake may change with time after ischaemia, careful interpretation of BMIPP uptake after ischaemia is required in a clinical setting.

  8. Acute mesenteric ischaemia and unexpected death.

    Science.gov (United States)

    Byard, Roger W

    2012-05-01

    Acute mesenteric ischaemia is a vascular emergency that arises when blood flow to the intestine is compromised leading to tissue necrosis. It is primarily a condition of the elderly associated with significant morbidity and mortality. Causes include arterial thromboembolism, venous thrombosis and splanchnic vasoconstriction (so-called nonocclusive mesenteric ischaemia). Reperfusion injury and breakdown of the intestinal mucosal barrier lead to metabolic derangements, sepsis and death from multiorgan failure. The diagnosis may be difficult to make clinically and numbers of cases are increasing due to ageing of the population. The clinical and pathological features are reviewed with discussion of predisposing conditions. Careful dissection of the mesenteric vasculature is required at autopsy with appropriate histologic sampling and documentation of associated comorbidities. Other organs need to be checked for thrombi and the possibility of testing for inherited thombophilias should be considered. Toxicological evaluation, particularly in younger individuals, may reveal evidence of cocaine use. On occasion no obstructive lesions will be demonstrated, however the confounding effects of post-mortem autolytic and putrefactive changes may mean that nonocclusive mesenteric ischaemia may be difficult to diagnose. Copyright © 2012 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  9. Myocardial Bridge

    Science.gov (United States)

    ... Center > Myocardial Bridge Menu Topics Topics FAQs Myocardial Bridge Article Info En español Your heart is made ... surface of the heart. What is a myocardial bridge? A myocardial bridge is a band of heart ...

  10. Evaluation of ischaemia in acute stroke using 18F labelled fluoromisonidazole (F-MISO)

    International Nuclear Information System (INIS)

    Sachinidis, J.I.; Tochon-Danguy, H.J.; Read, S.J.; Chan, J.G.; Egan, G.F.; McKay, W.J.; Scott, A.M.; Berlangieri, S.U.; Bladin, C.F.; Donna, G.A.

    1997-01-01

    Full text: Positron emission tomography (PET) using 18 F labelled fluoromisonidazole is a non-invasive technique for the detection hypoxic but viable tissue in malignant tumours, myocardial infarct and cerebral ischaemia. We have used F-MISO PET to detect hypoxia, likely to represent ischaemic penumbra, in patients after acute ischaemic stroke. Eight patients were studied at varying times after acute ischaemic stroke (from 95% chemical and radiochemical purity. Images were acquired at 2-5 h after injection in 3-D mode with a 10 min transmission scan followed by a 30-40 min emission scan. Four of the eight patients (studied at 12 hours, 24 hours, 7 dab and 11 days) showed increased F-MISO uptake in the region of the acute infarction. The ratio of activity between the infarct region and the contralateral normal cerebral tissue was >1.3 in all these case, comparable to ratios seen in human tumours and animal models of myocardial ischaemia. These preliminary results indicate that F-MISO PET detects regions of hypoxia consistent with the ischaemic penumbra in some patients with acute ischaemic stroke. Surprisingly, penumbra tissue may be detected as late as 11 days after onset. Conversely the ischaemic process may be complete within 24 hours, thus producing no F-MISO trapping. These findings have important implications for the therapeutic window after stroke

  11. [Transient cerebral ischemic complications. The neurologist's point of view].

    Science.gov (United States)

    el Amrani, M; Bousser, M G

    1995-05-01

    Transient ischaemic attacks (TIA) are defined by the focal and sudden loss of a cerebral function or the vision of one eye, resolving without sequelae within 24 hours and related to a vascular cause, thromboembolic much more frequently than haemodynamic. TIA represent between 9% and 25% of all cerebrovascular accident (CVA) with a variable global incidence from one study to another, between 0.2 and 3.3/1,000/year. The natural history of TIA is characterized by an excess mortality and an increased risk of cerebral infarction and myocardial infarction. It is therefore essential to recognize these events in order to prescribe effective preventive treatment. The clinical picture is characterized by a usually brief focal deficit (2 to 30 min, on average) and a normal clinical examination. The diagnosis is therefore exclusively based on the clinical interview. Complementary investigations have a dual objective: 1) to eliminate other diseases likely to cause transient neurological manifestations, and 2) to detect the mechanism and cause of cerebral ischaemia; the commonest causes are atheromatous stenosis and emboligenic heart disease. In addition to the routine laboratory examinations, basic complementary investigations consist of cerebral CT scan, cervical ultrasound and echocardiography. Conventional angiography is performed less and less frequently due to the progress in ultrasound and vascular imaging (helicoidal CT scan and magnetic resonance angiography). The treatment of TIA is designed to prevent cerebral and myocardial infarction, and to decrease the cardiovascular mortality [2]. In the short-term, it is essentially based on heparin, while waiting for the results of the aetiological assessment.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Selective heart rate reduction with ivabradine slows ischaemia-induced electrophysiological changes and reduces ischaemia–reperfusion-induced ventricular arrhythmias

    Science.gov (United States)

    Ng, Fu Siong; Shadi, Iqbal T.; Peters, Nicholas S.; Lyon, Alexander R.

    2013-01-01

    Heart rates during ischaemia and reperfusion are possible determinants of reperfusion arrhythmias. We used ivabradine, a selective If current inhibitor, to assess the effects of heart rate reduction (HRR) during ischaemia–reperfusion on reperfusion ventricular arrhythmias and assessed potential anti-arrhythmic mechanisms by optical mapping. Five groups of rat hearts were subjected to regional ischaemia by left anterior descending artery occlusion for 8 min followed by 10 min of reperfusion: (1) Control n = 10; (2) 1 μM of ivabradine perfusion n = 10; (3) 1 μM of ivabradine + 5 Hz atrial pacing throughout ischaemia–reperfusion n = 5; (4) 1 μM of ivabradine + 5 Hz pacing only at reperfusion; (5) 100 μM of ivabradine was used as a 1 ml bolus upon reperfusion. For optical mapping, 10 hearts (ivabradine n = 5; 5 Hz pacing n = 5) were subjected to global ischaemia whilst transmembrane voltage transients were recorded. Epicardial activation was mapped, and the rate of development of ischaemia-induced electrophysiological changes was assessed. HRR observed in the ivabradine group during both ischaemia (195 ± 11 bpm vs. control 272 ± 14 bpm, p hearts (27.7 ± 4.3 min vs. 14.5 ± 0.6 min, p Heart rate during ischaemia is a major determinant of reperfusion arrhythmias. Heart rate at reperfusion alone was not a determinant of reperfusion VF, as neither a bolus of ivabradine nor pacing immediately prior to reperfusion significantly altered reperfusion VF incidence. This anti-arrhythmic effect of heart rate reduction during ischaemia may reflect slower development of ischaemia-induced electrophysiological changes. PMID:23402927

  13. Changes in intestinal electrical activity during ischaemia correlate to ...

    African Journals Online (AJOL)

    To study this, the electrical activity of the ileum in 14 adult male rabbits was recorded during ischaemia. At baseline, 60, 120 and 210 minutes of ischaemia, segments of bowel were resected for histopathologic evaluation. The BER frequency was determined using the Fast Fourier Transformation (FFT) spectral analysis.

  14. Effect of corilagin on cerebral ischaemia/reperfusioninduced ...

    African Journals Online (AJOL)

    Purpose: To evaluate the neuroprotective effects of corilagin in cerebral ischaemia-induced cerebral injury in a rat model. Methods: Cerebral ischaemia was induced by middle cerebral artery occlusion (MCAO). The animals were separated into five groups, including a control group that underwent surgery without inserting a ...

  15. Short communication:Intestinal Ischaemia-Reperfusion Injury and ...

    African Journals Online (AJOL)

    Summary: Increasing production of goats takes their reproductive potential and fertility, into consideration. Gastrointestinal obstructive lesions can set up an intestinal ischaemia-reperfusion. Testicular torsion is an established cause of testicular damage and infertility and is a form of ischaemia-reperfusion injury. This study ...

  16. Nocturnal hypoxaemia after myocardial infarction: association with nocturnal myocardial ischaemia and arrhythmias

    DEFF Research Database (Denmark)

    Galatius-Jensen, S; Hansen, J; Rasmussen, Verner

    1994-01-01

    -0700) with a Holter tape recorder and a pulse oximeter. Fifteen patients were monitored for five nights, one patient for four nights, one patient for three nights, and two patients for two nights. RESULTS--Five patients had > 30 episodic oxygen desaturations of > or = 5% during the nights of monitoring and many...

  17. Lack of indication of myocardial cell damage after myocardial ischaemia in patients with severe stable angina

    DEFF Research Database (Denmark)

    Hansen, Knud Nørregaard; Egstrup, K; Nielsen, J R

    1992-01-01

    stenosis of one or more of the main coronary arteries and more than five ischaemic attacks per week. ST-segment monitoring was performed for 36 h. During the last 24 h of that period (period A) serial blood samples were analysed for myoglobin, CK and CK-MB using sensitive assays. Three days later (period B...

  18. Renal blood flow and metabolism after cold ischaemia

    DEFF Research Database (Denmark)

    Henriksen, J H; Petersen, H K

    1984-01-01

    Peroperative measurements of renal blood flow (RBF), renal O2-uptake, and renal venous lactate/pyruvate (L/P) ratio were performed before and after a period of 30-71 min of hypothermic (10-15 degrees C) renal ischaemia in nine patients, undergoing surgery for renal calculi. Before ischaemia, RBF.......01) immediately after re-established perfusion and 36% (P less than 0.02) 30 min later. In one additional patient, who had a short warm ischaemia (8 min), the flow pattern was the same. As arterial pressure remained constant, the reduced RBF signifies an increased renal vascular resistance. Renal O2-uptake...

  19. 9th Hatter Biannual Meeting: position document on ischaemia/reperfusion injury, conditioning and the ten commandments of cardioprotection.

    Science.gov (United States)

    Bell, R M; Bøtker, H E; Carr, R D; Davidson, S M; Downey, J M; Dutka, D P; Heusch, G; Ibanez, B; Macallister, R; Stoppe, C; Ovize, M; Redington, A; Walker, J M; Yellon, D M

    2016-07-01

    In the 30 years since the original description of ischaemic preconditioning, understanding of the pathophysiology of ischaemia/reperfusion injury and concepts of cardioprotection have been revolutionised. In the same period of time, management of patients with coronary artery disease has also been transformed: coronary artery and valve surgery are now deemed routine with generally excellent outcomes, and the management of acute coronary syndromes has seen decade on decade reductions in cardiovascular mortality. Nonetheless, despite these improvements, cardiovascular disease and ischaemic heart disease in particular, remain the leading cause of death and a significant cause of long-term morbidity (with a concomitant increase in the incidence of heart failure) worldwide. The need for effective cardioprotective strategies has never been so pressing. However, despite unequivocal evidence of the existence of ischaemia/reperfusion in animal models providing a robust rationale for study in man, recent phase 3 clinical trials studying a variety of cardioprotective strategies in cardiac surgery and acute ST-elevation myocardial infarction have provided mixed results. The investigators meeting at the Hatter Cardiovascular Institute workshop describe the challenge of translating strong pre-clinical data into effective clinical intervention strategies in patients in whom effective medical therapy is already altering the pathophysiology of ischaemia/reperfusion injury-and lay out a clearly defined framework for future basic and clinical research to improve the chances of successful translation of strong pre-clinical interventions in man.

  20. The effect of C-reactive protein deposition on myocardium with ischaemia-reperfusion injury in rats.

    Science.gov (United States)

    Oh, Se Jin; Na Kim, Eun; Jai Kim, Chong; Choi, Jae-Sung; Kim, Ki-Bong

    2017-08-01

    We evaluated the effect of monomeric C-reactive protein (CRP) deposition on areas at risk (AAR) of myocardium with ischaemia-reperfusion injury. Myocardial ischaemia-reperfusion injury model was produced by ligation of the left anterior descending coronary artery for 45 min followed by 45 min of reperfusion using female Sprague-Dawley rats. Tissue from non-ischaemic areas, areas at risk and infarct areas determined by Evans blue and 2,3,5-triphenyltetrazolium chloride staining was obtained from the sham group, the ischaemia-reperfusion injury without C-reactive protein (CRP) injection group (I/R only group), and the ischaemia-reperfusion injury with CRP injection group (I/R + CRP group). We assessed the effect of CRP injection on infarct size, CRP deposition, CRP and IL-6 mRNA expression, the third component of complement (C3) immunodeposition and mitochondrial structural remodelling with apoptosis by quantitative RT-PCR analyses, immunohistochemistry, direct immunofluorescence, electron microscopy and Terminal deoxynucleotide transferase dUTP Nick End Labelling assay, respectively. All images were analysed using an automated morphology tool. The infarct area significantly increased in the I/R + CRP group compared to the I/R only group. The anti CRP antibody confirmed that CRP deposition occurred in both the infarct and area at risk (AAR) of the I/R + CRP group. The myocardium did not exhibit CRP mRNA expression, and the CRP treatment group showed a tendency for IL-6 to increase without statistical significance. Activated C3, apoptosis and mitochondrial destruction increased on AAR and infarct area in the I/R + CRP group. These results strongly suggest the active participation of the deposition of CRP on AAR in the progression of myocardial infarction following ischaemia-reperfusion injury, accompanied by complement activation and mitochondrial change. © The Author 2017. Published by Oxford University Press on behalf of the European Association

  1. Renal blood flow and metabolism after cold ischaemia

    DEFF Research Database (Denmark)

    Henriksen, J H; Petersen, H K

    1984-01-01

    .01) immediately after re-established perfusion and 36% (P less than 0.02) 30 min later. In one additional patient, who had a short warm ischaemia (8 min), the flow pattern was the same. As arterial pressure remained constant, the reduced RBF signifies an increased renal vascular resistance. Renal O2-uptake......Peroperative measurements of renal blood flow (RBF), renal O2-uptake, and renal venous lactate/pyruvate (L/P) ratio were performed before and after a period of 30-71 min of hypothermic (10-15 degrees C) renal ischaemia in nine patients, undergoing surgery for renal calculi. Before ischaemia, RBF...... and renal venous L/P ratio were almost constant, indicating no significant anaerobic processes being involved in the flow response. None of the patients showed any signs of reactive hyperaemia. It is concluded that hypothermic renal ischaemia may be followed by an increased renal vascular resistance even...

  2. Management of renal dysfunction following term perinatal hypoxia-ischaemia.

    LENUS (Irish Health Repository)

    Sweetman, Deirdre U

    2013-03-01

    Acute kidney injury frequently develops following the term perinatal hypoxia-ischaemia. Quantifying the degree of acute kidney injury is difficult, however, as the methods currently in use are suboptimal. Acute kidney injury management is largely supportive with little evidence basis for many interventions. This review discusses management strategies and novel biomarkers that may improve diagnosis and management of renal injury following perinatal hypoxia-ischaemia.

  3. Ischaemia-reperfusion injury in chronic kidney disease

    OpenAIRE

    Veighey, K. V.

    2015-01-01

    When an organ or tissue is rendered ischaemic, there is inevitable cell death and tissue injury, the extent of which can be limited by timely reperfusion. However, paradoxically, an additional injury occurs upon reperfusion that limits the amount of tissue that can be salvaged. This composite injury is termed ‘ischaemia-reperfusion (IR) injury’. Ischaemic preconditioning (IPC) is an innate protective phenomenon whereby brief non-lethal periods of ischaemia and reperfusion may protect against ...

  4. Effect of sodium nitrite on ischaemia and reperfusion-induced arrhythmias in anaesthetized dogs: is protein S-nitrosylation involved?

    Directory of Open Access Journals (Sweden)

    Mária Kovács

    Full Text Available To provide evidence for the protective role of inorganic nitrite against acute ischaemia and reperfusion-induced ventricular arrhythmias in a large animal model.Dogs, anaesthetized with chloralose and urethane, were administered intravenously with sodium nitrite (0.2 µmol kg(-1 min(-1 in two protocols. In protocol 1 nitrite was infused 10 min prior to and during a 25 min occlusion of the left anterior descending (LAD coronary artery (NaNO2-PO; n = 14, whereas in protocol 2 the infusion was started 10 min prior to reperfusion of the occluded vessel (NaNO2-PR; n = 12. Control dogs (n = 15 were infused with saline and subjected to the same period of ischaemia and reperfusion. Severities of ischaemia and ventricular arrhythmias, as well as changes in plasma nitrate/nitrite (NOx levels in the coronary sinus blood, were assessed throughout the experiment. Myocardial superoxide and nitrotyrosine (NT levels were determined during reperfusion. Changes in protein S-nitrosylation (SNO and S-glutathionylation were also examined.Compared with controls, sodium nitrite administered either pre-occlusion or pre-reperfusion markedly suppressed the number and severity of ventricular arrhythmias during occlusion and increased survival (0% vs. 50 and 92% upon reperfusion. There were also significant decreases in superoxide and NT levels in the nitrite treated dogs. Compared with controls, increased SNO was found only in NaNO2-PR dogs, whereas S-glutathionylation occurred primarily in NaNO2-PO dogs.Intravenous infusion of nitrite profoundly reduced the severity of ventricular arrhythmias resulting from acute ischaemia and reperfusion in anaesthetized dogs. This effect, among several others, may result from an NO-mediated reduction in oxidative stress, perhaps through protein SNO and/or S-glutathionylation.

  5. Value of cerebral blood flow rate and regional oxygen consumption studies in cerebral ischaemia

    International Nuclear Information System (INIS)

    Clanet, M.

    1987-01-01

    Studies of experimentally-induced ischaemia have shown that the intensity of neuronal suffering is related to the fall in perfusion rate. Below a certain level, called functional threshold, cerebral function is reversibly altered, whereas at a lower level (tissue necrosis threshold) the damage inflicted on neurons is irreversible. Between these two thresholds lies a ''penumbra zone''. This concept of thresholds must be mitigated by 2 parameters: duration of ischaemia and selective vulnerability of the various structures affected. Variations in blood flow rate only indirectly affect the state of tissues. Techniques developed from positron emission tomography make it possible to evaluate the metabolic activity of brain tissue in vivo: oxygen consumption (CMRO 2 ), oxygen extraction (EO 2 ) and glucose consumption (CMRG) which are thus correlated to cerebral blood flow and cerebral blood volume, sometimes also to tissue pH. Normal relations between blood flow rate and metabolism may be altered. Misery perfusion reflects a fall in cerebral blood flow with an increase in EO 2 and often a decrease in CMRO 2 , whereas luxury perfusion reflects an increase in cerebral blood flow rate with reduction of CMRO 2 , EO 2 and CMRG. The type of alteration encountered in human ischaemia varies according to the nature of the accident: studies of transient accidents emphasize the different haemodynamic aspects of occlusion of the wider arteries. The metabolic and haemodynamic profiles of established ischaemic accidents vary according to their type and to the time of the study, reflecting the complexity of the physiopathological mechanisms involved; they are frequently associated with metabolic repercussions at a distance from the ischaemic focus, which supports the concept of diaschisis [fr

  6. Value of cerebral blood flow rate and regional oxygen consumption studies in cerebral ischaemia

    Energy Technology Data Exchange (ETDEWEB)

    Clanet, M.

    1987-06-18

    Studies of experimentally-induced ischaemia have shown that the intensity of neuronal suffering is related to the fall in perfusion rate. Below a certain level, called functional threshold, cerebral function is reversibly altered, whereas at a lower level (tissue necrosis threshold) the damage inflicted on neurons is irreversible. Between these two thresholds lies a ''penumbra zone''. This concept of thresholds must be mitigated by 2 parameters: duration of ischaemia and selective vulnerability of the various structures affected. Variations in blood flow rate only indirectly affect the state of tissues. Techniques developed from positron emission tomography make it possible to evaluate the metabolic activity of brain tissue in vivo: oxygen consumption (CMRO/sub 2/), oxygen extraction (EO/sub 2/) and glucose consumption (CMRG) which are thus correlated to cerebral blood flow and cerebral blood volume, sometimes also to tissue pH. Normal relations between blood flow rate and metabolism may be altered. Misery perfusion reflects a fall in cerebral blood flow with an increase in EO/sub 2/ and often a decrease in CMRO/sub 2/, whereas luxury perfusion reflects an increase in cerebral blood flow rate with reduction of CMRO/sub 2/, EO/sub 2/ and CMRG. The type of alteration encountered in human ischaemia varies according to the nature of the accident: studies of transient accidents emphasize the different haemodynamic aspects of occlusion of the wider arteries. The metabolic and haemodynamic profiles of established ischaemic accidents vary according to their type and to the time of the study, reflecting the complexity of the physiopathological mechanisms involved; they are frequently associated with metabolic repercussions at a distance from the ischaemic focus, which supports the concept of diaschisis.

  7. Secondary prevention after cerebral ischaemia of presumed arterial origin: is aspirin still the touchstone?

    NARCIS (Netherlands)

    A. Algra (Ale); P.J. Koudstaal (Peter Jan); J. van Gijn (Jan)

    1999-01-01

    textabstractPatients who have had a transient ischaemic attack or nondisabling ischaemic stroke of presumed arterial origin have an annual risk of death from all vascular causes, non-fatal stroke, or non-fatal myocardial infarction that ranges between 4% and 11% without treatment. In the

  8. A decision support system improves the interpretation of myocardial perfusion imaging

    International Nuclear Information System (INIS)

    Taegil, K.; Bondouy, M.; Chaborel, J.P.; Franken, P.R.; Djaballah, W.; Grandpierre, S.; Marie, P.Y.; Poisson, T.; Hesse, B.; Lomsky, M.; Edenbrandt, L.

    2008-01-01

    The aim of this study was to investigate the influence of a computer-based decision support system (DSS) on performance and inter-observer variability of interpretations regarding ischaemia and infarction in myocardial perfusion scintigraphy (MPS). Seven physicians independently interpreted 97 MPS studies, first without and then with the advice of a DSS. Four physicians had long experience and three had limited experience in the interpretation of MPS. Each study was interpreted regarding myocardial ischaemia and infarction in five myocardial regions. The patients had undergone a gated MPS using a 2-day stress/gated rest 99m Tc sestamibi protocol. The gold standard used was the interpretations made by one experienced nuclear medicine specialist on the basis of all available clinical and image information. The sensitivity for ischaemia of the seven readers increased from 81% without the DSS to 86% with the DSS (p 0.01). The increase in sensitivity was higher for the three inexperienced physicians (9%) than for the four experienced physicians (2%). There was no significant change in specificity between the interpretations. The interpretations of ischaemia made with the advice of the DSS showed less inter-observer variability than those made without advice. This study shows that a DSS can improve performance and reduces the inter-observer variability of interpretations in myocardial perfusion imaging. Both experienced and, especially, inexperienced physicians can improve their interpretation with the advice from such a system. (orig.)

  9. Vitamin C deficiency and risk of myocardial infarction: prospective population study of men from eastern Finland.

    OpenAIRE

    Nyyssönen, K.; Parviainen, M. T.; Salonen, R.; Tuomilehto, J.; Salonen, J. T.

    1997-01-01

    OBJECTIVE: To examine the association between plasma vitamin C concentrations and the risk of acute myocardial infarction. DESIGN: Prospective population study. SETTING: Eastern Finland. SUBJECTS: 1605 randomly selected men aged 42, 48, 54, or 60 who did not have either symptomatic coronary heart disease or ischaemia on exercise testing at entry to the Kuopio ischaemic heart disease risk factor study in between 1984 and 1989. MAIN OUTCOME MEASURES: Number of acute myocardial infarctions; fast...

  10. Efficacy and Safety of Vorapaxar With and Without a Thienopyridine for Secondary Prevention in Patients With Previous Myocardial Infarction and No History of Stroke or Transient Ischemic Attack: Results from TRA 2°P-TIMI 50.

    Science.gov (United States)

    Bohula, Erin A; Aylward, Philip E; Bonaca, Marc P; Corbalan, Ramon L; Kiss, Robert G; Murphy, Sabina A; Scirica, Benjamin M; White, Harvey; Braunwald, Eugene; Morrow, David A

    2015-11-17

    Vorapaxar antagonizes protease-activated receptor 1, the primary receptor for thrombin on human platelets, and reduces recurrent thrombotic events in stable patients with a previous myocardial infarction (MI). We wished to determine whether the efficacy and safety of antiplatelet therapy with vorapaxar was modified by concurrent thienopyridine use. The Thrombin Receptor Antagonist in Secondary Prevention of Atherothrombotic Ischemic Events-Thrombolysis in Myocardial Infarction 50 (TRA 2°P-TIMI 50) was a randomized, double-blind, placebo-controlled trial of vorapaxar in 26,449 patients with previous atherothrombosis. This prespecified analysis included 16,897 patients who qualified with a MI in the preceding 2 weeks to 12 months and was restricted to patients without a history of stroke or transient ischemic attack given its contraindication in that population. Randomization was stratified on the basis of planned thienopyridine use. Thienopyridine was planned at randomization in 12,410 (73%). Vorapaxar significantly reduced the composite of cardiovascular death, MI, and stroke in comparison with placebo regardless of planned thienopyridine therapy (planned thienopyridine, hazard ratio, 0.80, 0.70-0.91, PGlobal Use of Strategies to Open Occluded Coronary Arteries (GUSTO) moderate or severe bleeding risk was increased with vorapaxar and was not significantly altered by planned thienopyridine (planned, hazard ratio, 1.50; 1.18-1.89, Phistory of previous MI, whether treated concomitantly with a thienopyridine or not. The relative risk of moderate or severe bleeding was similarly increased irrespective of thienopyridine use. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00526474. © 2015 American Heart Association, Inc.

  11. Predictive and prognostic values of transient ischemic dilatation of left ventricular cavity for coronary artery disease and impact of various managements on clinical outcome using technetium-99m sestamibi gated myocardial perfusion imaging

    International Nuclear Information System (INIS)

    Zaman, M.U.; Fatima, N.; Samad, A.; Ishaq, M.; Wali, A.; Rehman, K.; Bano, J.

    2011-01-01

    Transient ischemic dilatation (TID) of left ventricular (LV) cavity during stress gated myocardial perfusion imaging (GMPI) is known as a predictor of severe coronary artery disease (CAD) and signifies worse prognosis. To assess predictive and prognostic value of TID of LV cavity using GMPI and clinical outcome in patients treated conservatively or with revascularization. 189 patients out of 2689 were recruited (M:F 127/62, mean age 56±9 years) whose same-day stress GMPI revealed TID ratio (>1.22) with no (sum stress score, SSS 2). Coronary angiography (CA) was performed within 3 months in 125/189 cases who were followed for mean period of 18±4 months for fatal or non-fatal myocardial infraction (MI). CA was positive in 121/125 patients with TID for significant CAD (left anterior descending (LAD) =11, multi vessel disease =110 patients, positive predictive value 95%) and negative for obstructive disease in 4/125 (false-positive cases). 41/121 underwent revascularization within 2 months of CA (Intervention group), and remaining 80/121 were managed conservatively (Non-Intervention group). Overall event rate was 20% (4/16%: fatal/non-fatal MIs). Kaplan-Meier survival curves revealed event-free survival in Intervention and Non-Intervention groups for fatal MI 98/96% (P=0.758), and for non-fatal MI, it was 97/58%, respectively (P=0.042). We conclude that TID is a reliable predictor of multi vessel CAD and is associated with high incidence of non-fatal MIs than fatal MIs. Revascularization (percutaneous coronary intervention (PCI)/coronary artery bypass graft (CABG)) rather than medical treatment should be considered in patients with TID for better clinical outcome. (author)

  12. Normobaric hyperoxia markedly reduces brain damage and sensorimotor deficits following brief focal ischaemia.

    Science.gov (United States)

    Ejaz, Sohail; Emmrich, Julius V; Sitnikov, Sergey L; Hong, Young T; Sawiak, Stephen J; Fryer, Tim D; Aigbirhio, Franklin I; Williamson, David J; Baron, Jean-Claude

    2016-03-01

    'True' transient ischaemic attacks are characterized not only clinically, but also radiologically by a lack of corresponding changes on magnetic resonance imaging. During a transient ischaemic attack it is assumed that the affected tissue is penumbral but rescued by early spontaneous reperfusion. There is, however, evidence from rodent studies that even brief focal ischaemia not resulting in tissue infarction can cause extensive selective neuronal loss associated with long-lasting sensorimotor impairment but normal magnetic resonance imaging. Selective neuronal loss might therefore contribute to the increasingly recognized cognitive impairment occurring in patients with transient ischaemic attacks. It is therefore relevant to consider treatments to reduce brain damage occurring with transient ischaemic attacks. As penumbral neurons are threatened by markedly constrained oxygen delivery, improving the latter by increasing arterial O2 content would seem logical. Despite only small increases in arterial O2 content, normobaric oxygen therapy experimentally induces significant increases in penumbral O2 pressure and by such may maintain the penumbra alive until reperfusion. Nevertheless, the effects of normobaric oxygen therapy on infarct volume in rodent models have been conflicting, although duration of occlusion appeared an important factor. Likewise, in the single randomized trial published to date, early-administered normobaric oxygen therapy had no significant effect on clinical outcome despite reduced diffusion-weighted imaging lesion growth during therapy. Here we tested the hypothesis that normobaric oxygen therapy prevents both selective neuronal loss and sensorimotor deficits in a rodent model mimicking true transient ischaemic attack. Normobaric oxygen therapy was applied from the onset and until completion of 15 min distal middle cerebral artery occlusion in spontaneously hypertensive rats, a strain representative of the transient ischaemic attack

  13. The transient receptor potential vanilloid 2 cation channel is abundant in macrophages accumulating at the peri-infarct zone and may enhance their migration capacity towards injured cardiomyocytes following myocardial infarction.

    Directory of Open Access Journals (Sweden)

    Michal Entin-Meer

    Full Text Available PURPOSE: A novel family of transient receptor potential (TRP channels, that may hold a role in calcium homeostasis, has recently been described. By employing a GeneChip array analysis we have demonstrated a clear and specific upregulation of the TRP vanilloid 2 (TRPV2 mRNA in the left ventricles (LV 3-5 days post-acute myocardial infarction (MI compared to sham-operated controls, both in rats and in mice. We sought to characterize the cardiac cellular subpopulations in which TRPV2 is overexpressed upon acute MI. METHODS: Lewis rats underwent an acute MI by ligation of the left anterior descending artery or chest opening only (sham. The animals were terminated at various time points and an immunohistochemical (IHC and immunofluorescent (IFC staining of the LV sections as well as a flow cytometry analysis of LV-derived cells were carried out, using anti-TRPV2 and anti-monocyte/macrophage antibodies. Rat alveolar macrophage cells, NR8383, transiently transfected with TRPV2 siRNA were allowed to migrate towards hypoxic conditioned media of the rat cardiac myoblast line H9C2 using a trans-well migration assay. The macrophage cells migrating to the bottom side of the inserts were counted. RESULTS: The IHC and IFC staining as well as the flow cytometry data demonstrated a substantial expression of TRPV2 in infiltrating macrophages in the peri-infarct region 3-5 days post-acute MI. The in vitro migration assay data demonstrated that following inhibition of the TRPV2 channel, the number of migrating macrophages towards conditioned medium of hypoxic cardiomyocytes was significantly reduced. CONCLUSIONS: TRPV2 is highly expressed on the peri-infarct infiltrating macrophages and may play an important role in post-MI phagocytosis. Better characterization of this channel may pave the way for identifying a new target for modulating the dramatic post-MI immune reactions.

  14. Myocardial contusion

    Science.gov (United States)

    ... 000202.htm Myocardial contusion To use the sharing features on this page, please enable JavaScript. Myocardial contusion ... Wear a seat belt when driving. Choose a car with air bags. Take steps to ensure safety when working at heights. Alternative Names Blunt myocardial ...

  15. MRI monitoring of experimental cerebral ischaemia: comparison of two models

    International Nuclear Information System (INIS)

    Forsting, M.; Reith, W.; Doerfler, A.; Meyding-Lamade, U.; Sartor, K.

    1994-01-01

    The aim of this study was to compare two minimally invasive rat models of focal ischaemic stroke as to their ability to simulate clinical stroke reproducibly. In one model a focal infarct was induced using the photochemical Rose Bengal technique. The second model was based on transvascular occlusion of the middle cerebral artery using a cervical approach. In all animals we performed MRI at different times with two different paramagnetic contrast agents. The time course of blood-brain-barrier disruption in the Rose Bengal model differed entirely from that in human brain ischaemia. The experimental stroke showed marked contrast enhancement in the first hour after the onset of ischaemia. On the other hand, the MRI changes in the suture occlusion model were very similar to the changes observed in human brain ischaemia: no early disruption of the blood-brain-barrier and increased T2-signal 4-6 h after the onset of stroke. (orig.)

  16. Hydroxychloroquine Protects against Cardiac Ischaemia/Reperfusion Injury In Vivo via Enhancement of ERK1/2 Phosphorylation

    Science.gov (United States)

    Bourke, Lauren; McCormick, James; Taylor, Valerie; Pericleous, Charis; Blanchet, Benoit; Costedoat-Chalumeau, Nathalie; Stuckey, Daniel; Lythgoe, Mark F.; Stephanou, Anastasis; Ioannou, Yiannis

    2015-01-01

    An increasing number of investigations including human studies demonstrate that pharmacological ischaemic preconditioning is a viable way to protect the heart from myocardial ischaemia/reperfusion (I/R) injury. This study investigated the role of hydroxychloroquine (HCQ) in the heart during I/R injury. In vitro and in vivo models of myocardial I/R injury were used to assess the effects of HCQ. It was found that HCQ was protective in neonatal rat cardiomyocytes through inhibition of apoptosis, measured by TUNEL and cleaved caspase-3. This protection in vitro was mediated through enhancement of ERK1/2 phosphorylation mediated by HCQ in a dose-dependent fashion. A decrease in infarct size was observed in an in vivo model of myocardial I/R injury in HCQ treated animals and furthermore this protection was blocked in the presence of the ERK1/2 inhibitor U0126. For the first time, we have shown that HCQ promotes a preconditioning like protection in an in vivo simulated rat myocardial I/R injury model. Moreover, it was shown that HCQ is protective via enhanced phosphorylation of the pro-survival kinase ERK1/2. PMID:26636577

  17. Non-occlusive mesenteric ischaemia in out of hospital cardiac arrest survivors.

    Science.gov (United States)

    Wurm, Raphael; Cho, Anna; Arfsten, Henrike; van Tulder, Raphael; Wallmüller, Christian; Steininger, Philipp; Sterz, Fritz; Tendl, Kristina; Balassy, Csilla; Distelmaier, Klaus; Hülsmann, Martin; Heinz, Gottfried; Adlbrecht, Christopher

    2017-01-01

    Non-occlusive mesenteric ischaemia (NOMI) is characterised by hypoperfusion of the intestines without evidence of mechanical obstruction, potentially leading to extensive ischaemia and necrosis. Low cardiac output appears to be a major risk factor. Cardiopulmonary resuscitation aims at restoring blood flow after cardiac arrest. However, post restoration of spontaneous circulation, myocardial stunning limits immediate recovery of sufficient cardiac function. Since after successful cardiopulmonary resuscitation patients are often ventilated and sedated, NOMI might be underdiagnosed and potentially life-saving treatment delayed. A prospectively maintained multi-purpose cohort of out of hospital cardiac arrest survivors, who had successful restoration of spontaneous circulation, was used for this retrospective database analysis. Patients' charts were screened for clinical, radiological or pathological evidence of NOMI and clinical data were collected. Between 2000 and 2014, 1780 patients who were successfully resuscitated after out of hospital cardiac arrest were screened for NOMI. Twelve patients (0.68 %) suffered from NOMI and six of those died (50 %). Patients suffering from NOMI tended to have a longer duration until restoration of spontaneous circulation (27 vs. 20 min, p=0.128) and had significantly higher lactate (14 mmol/l vs. 8 mmol/l, p=0.002) and base deficit levels at admission (-17 vs. -10, p=0.012). Median leukocyte counts in NOMI patients peaked at the day of diagnosis. NOMI is a rare but life-threatening and potentially curable complication following successful cardiopulmonary resuscitation. Lactate and base deficit at admission could help to identify patients at risk for developing NOMI who might benefit from increased clinical attention.

  18. Monophosphoryl lipid A provides biphasic cardioprotection against ischaemia-reperfusion injury in rat hearts.

    Science.gov (United States)

    Yamashita, N; Hoshida, S; Otsu, K; Taniguchi, N; Kuzuya, T; Hori, M

    1999-09-01

    1 We utilized a rat model of myocardial infarction to investigate whether cardioprotection by monophosphoryl lipid A (MLA) is provided in the early and late phases, as well as to determine whether this cardioprotection may be related to the activation of manganese superoxide dismutase (Mn-SOD), an intrinsic radical scavenger. 2 Pretreatment with MLA (0.5 or 1.0 mg kg-1, i.v.) 24 h prior to 20-min left coronary artery (LCA) occlusion and 48-h reperfusion significantly decreased the incidence of ventricular fibrillation (VF) during ischaemia, as well as infarct size. Pretreatment with lower concentrations of MLA, however, was ineffective. 3 When we examined the time course of MLA (0.5 mg kg-1)-induced cardioprotection, both infarct size and the incidence of VF were significantly reduced in rats pretreated with MLA 0.5 h and 24 h before occlusion. We observed no differences, however, 2 and 72 h after MLA treatment. 4 The activity of Mn-SOD paralleled the cardioprotective effects of MLA. Mn-SOD activity in the myocardium was significantly enhanced in rats pretreated with MLA (0.5 mg kg-1) 0.5 and 24 h before. Mn-SOD activity was not altered, however, in rats pretreated 2 or 72 h before. Lower MLA concentrations were not effective even 24 h after the treatment. 5 We conclude that MLA treatment induced a biphasic pattern of cardioprotection. The pattern of Mn-SOD activity suggests that this enzyme may play a major role in the acquisition of cardioprotection against ischaemia-reperfusion injury.

  19. Evaluation of a decision support system for interpretation of myocardial perfusion gated SPECT.

    Science.gov (United States)

    Lomsky, Milan; Gjertsson, Peter; Johansson, Lena; Richter, Jens; Ohlsson, Mattias; Tout, Deborah; van Aswegen, Andries; Underwood, S Richard; Edenbrandt, Lars

    2008-08-01

    We have recently presented a decision support system for interpreting myocardial perfusion scintigraphy (MPS). In this study, we wanted to evaluate the system in a separate hospital from where it was trained and to compare it with a quantification software package. A completely automated method based on neural networks was trained for the interpretation of MPS regarding myocardial ischaemia and infarction using 418 MPS from one hospital. Features from each examination describing rest and stress perfusion, regional and global function were used as inputs to different neural networks. After the training session, the system was evaluated using 532 MPS from another hospital. The test images were also processed with the quantification software package Emory Cardiac Toolbox (ECTb). The images were interpreted by experienced clinicians at both the training and the test hospital, regarding the presence or absence of myocardial ischaemia and/or infarction and these interpretations were used as gold standard. The neural network showed a sensitivity of 90% and a specificity of 85% for myocardial ischaemia. The specificity for the ECTb was 46% (p neural network sensitivity for myocardial infarction was 89% and the specificity 96%. The corresponding specificity for the ECTb was 54% (p neural networks presents interpretations more similar to experienced clinicians compared to a conventional automated quantification software package. This study shows the feasibility of disseminating the expertise of experienced clinicians to less experienced physicians by the use of neural networks.

  20. Metformin induces cardioprotection against ischaemia/reperfusion injury in the rat heart 24 hours after administration.

    Science.gov (United States)

    Solskov, Lasse; Løfgren, Bo; Kristiansen, Steen B; Jessen, Niels; Pold, Rasmus; Nielsen, Torsten T; Bøtker, Hans Erik; Schmitz, Ole; Lund, Sten

    2008-07-01

    The UK Prospective Diabetes Study demonstrated that the hypoglycaemic drug metformin is associated with a reduction in cardiovascular events in a group of obese type 2 diabetes patients. The energy sensing enzyme AMP-activated protein kinase (AMPK) has been indicated to play an important protective role in the ischaemic heart and is activated by metformin. The aim of this study was to determine whether a single dose of metformin protects the myocardium against experimentally induced ischaemia 24 hr after the administration, and furthermore to determine whether a single dose of metformin results in an acute increase in myocardial AMPK activity. Wistar rats were given either a single oral dose of metformin (250 mg/kg body weight), or a single oral dose of saline. After 24 hr, the hearts were Langendorff-perfused and subjected to 45 min. of coronary artery occlusion. Infarct size was determined by staining with triphenyltetrazoliumchloride (TTC) and Evans Blue and expressed as a percentage of the risk zone (IS/AAR %). Isoform specific AMPK activity was measured 2 hr after administration of metformin or saline. Infarct size was significantly reduced in the metformin treated (I/R: 19.9 +/- 3.9%versus 36.7 +/- 3.6%, P < 0.01, n = 8-14) compared to the control group. A single oral dose of metformin resulted in an approximately ~2-fold increase in AMPK-alpha2 activity 2 hr after administration (P < 0.015, n = 10). In conclusion, a single dose of metformin results in an acute increase in myocardial AMPK activity measured 2 hr after administration and induces a significant reduction in myocardial infarct size 24 hr after metformin administration. Increased AMPK activity may be an important signal mediator involved in the mechanisms behind the cardioprotective effects afforded by metformin.

  1. Treatment of severe foot ischaemia by defibrination with ancrod

    DEFF Research Database (Denmark)

    Tønnesen, K H; Sager, P; Gormsen, J

    1978-01-01

    Forty-two patients, mean age 68 years, with severe leg ischaemia were randomly treated with placebo or by controlled defibrination with ancrod for 3 weeks. Plasma fibrinogen concentration was kept at about 20% of normal in the ancrod treated group. The two groups proved to be well matched regardi...

  2. Treatment of severe foot ischaemia by defibrination with ancrod

    DEFF Research Database (Denmark)

    Tønnesen, K H; Sager, P; Gormsen, J

    1978-01-01

    factors which could affect the degree of ischaemia. Objective measurements showed a significant rise in ankle and toe systolic blood pressure in the ancrod group lasting for 3 months. There was no rise in distal blood pressure in the control group. In the ancrod treated group the toe and ankle systolic...

  3. Intestinal Ischaemia-Reperfusion Injury and Semen Characteristics ...

    African Journals Online (AJOL)

    olayemitoyin

    This study investigates the effect of intestinal ischaemia-reperfusion (IIR) injury on semen characteristics ... Increasing incidence of gastro-intestinal emergencies in sheep and goat are due to difficulties which include .... The semen characteristics of West African dwarf bucks infected with Listeria monocytogenes. Bull. Anim.

  4. Dislocated ankle fracture complicated by near total distal ischaemia

    Science.gov (United States)

    Duygun, Fatih; Sertkaya, Omer; Aldemir, Cengiz; Dogan, Ali

    2013-01-01

    Total arterial ischaemia is rarely seen following a dislocated ankle fracture but if it does and intervention is not made, it can lead to serious morbidity. We present a 39-year-old woman with almost total occlusion in the arteria tibialis and arteria dorsalis pedis following a dislocated ankle fracture as a result of a bicycle fall. PMID:24248319

  5. Human baroreflex rhythms persist during handgrip and muscle ischaemia

    Science.gov (United States)

    Eckberg, D. L.; Cooke, W. H.; Diedrich, A.; Levine, B. D.; Pawelczyk, J. A.; Buckey, J. C.; Ertl, A. C.; Biaggioni, I.; Cox, J. F.; Robertson, D.; Baisch, F. J.; Blomqvist, C. G.; Kuusela, T. A.; Tahvanainen, K. U. O.

    2013-01-01

    Aim To determine if physiological, rhythmic fluctuations of vagal baroreflex gain persist during exercise, post-exercise ischaemia, and recovery. Methods We studied responses of six supine healthy men and one woman to a stereotyped protocol comprising rest, handgrip exercise at 40 % maximum capacity to exhaustion, post-exercise forearm ischaemia, and recovery. We measured electrocardiographic R-R intervals, photoplethysmographic finger arterial pressures, and peroneal nerve muscle sympathetic activity. We derived vagal baroreflex gains from a sliding (25 s window moved by 2 s steps) systolic pressure – R-R interval transfer function at 0.04 – 0.15 Hz. Results Vagal baroreflex gain oscillated at low, nearly constant frequencies throughout the protocol (at ~ 0.06 Hz – a period of about 18 s); however, during exercise, most oscillations were at low gain levels, and during ischaemia and recovery, most oscillations were at high gain levels. Conclusions Vagal baroreflex rhythms are not abolished by exercise, and they are not overwhelmed after exercise during ischaemia and recovery. PMID:23809494

  6. Transcranial Doppler for detection of cerebral ischaemia during carotid endarterectomy

    DEFF Research Database (Denmark)

    Jørgensen, L G; Schroeder, T V

    1992-01-01

    We evaluated transcranial Doppler sonography (TCD) for the detection of cerebral ischaemia during carotid endarterectomy in 30 male and 14 female patients with ipsilateral focal cerebro-vascular symptoms. Surgery was performed during halothane-nitrous oxide anaesthesia with moderate hypocapnia...

  7. Myocardial Bridging

    Directory of Open Access Journals (Sweden)

    Shi-Min Yuan

    2016-02-01

    Full Text Available Abstract Myocardial bridging is rare. Myocardial bridges are most commonly localized in the middle segment of the left anterior descending coronary artery. The anatomic features of the bridges vary significantly. Alterations of the endothelial morphology and the vasoactive agents impact on the progression of atherosclerosis of myocardial bridging. Patients may present with chest pain, myocardial infarction, arrhythmia and even sudden death. Patients who respond poorly to the medical treatment with β-blockers warrant a surgical intervention. Myotomy is a preferred surgical procedure for the symptomatic patients. Coronary stent deployment has been in limited use due to the unsatisfactory long-term results.

  8. Tanshinone IIA pretreatment protects myocardium against ischaemia/reperfusion injury through the phosphatidylinositol 3-kinase/Akt-dependent pathway in diabetic rats.

    Science.gov (United States)

    Zhang, Y; Wei, L; Sun, D; Cao, F; Gao, H; Zhao, L; Du, J; Li, Y; Wang, H

    2010-04-01

    Diabetes Mellitus (DM) is widely acknowledged to increase the risk of cardiovascular death, which warrants the use of aggressive primary prevention strategies. The aim of the present study was to investigate the pretreatment effects of tanshinone IIA (TSN), a traditional Chinese medicine, on myocardial infarct size, apoptosis, inflammation and cardiac functional recovery in diabetic rats subjected to myocardial ischaemia/reperfusion (I/R). Streptozocin (STZ) induced diabetic rats (n = 80) were randomized to receive TSN, TSN plus wortmannin [a phosphatidylinositol 3-kinase (PI3K) inhibitor] or saline. They were exposed to a 30-min ischaemia by ligation of the left coronary artery except for the sham group. Haemodynamics, infarct size and myocardial apoptosis were examined 3 h after reperfusion. The effects of TSN on Akt and NF-kappaB phosphorylation and the expression of tumour necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in cardiac tissues were examined. Our results revealed that TSN administration significantly reduced myocardial infarct size (0.252 +/- 0.038 vs. 0.327 +/- 0.027, p TSN treatment enhanced Akt phosphorylation and inhibited NF-kappaB phosphorylation in cardiac tissues. Moreover, pretreatment with wortmannin abolished the beneficial effects of TSN: a reduction of infarct size, a decrease in LVEF, inhibition of myocardial apoptosis and Akt phosphorylation, enhancement of NF-kappaB phosphorylation and an increase of cytokine production including TNF-alpha and IL-6 after I/R injury in diabetic rats. This study indicates that TSN pretreatment reduces infarct size and improves cardiac dysfunction after I/R injury in diabetic rats. This was accompanied with decreased cardiac apoptosis and inflammation. The possible mechanism responsible for the effects of TSN is associated with the PI3K/Akt-dependent pathway.

  9. Reversing dobutamine-induced tachycardia using ivabradine increases stroke volume with neutral effect on cardiac energetics in left ventricular post-ischaemia dysfunction.

    Science.gov (United States)

    Bakkehaug, J P; Naesheim, T; Torgersen Engstad, E; Kildal, A B; Myrmel, T; How, O-J

    2016-10-01

    Compensatory tachycardia can potentially be deleterious in acute heart failure. In this study, we tested a therapeutic strategy of combined inotropic support (dobutamine) and selective heart rate (HR) reduction through administration of ivabradine. In an open-chest pig model (n = 12) with left ventricular (LV) post-ischaemia dysfunction, cardiac function was assessed by LV pressure catheter and sonometric crystals. Coronary flow and blood samples from the coronary sinus were used to measure myocardial oxygen consumption (MVO2 ). LV energetics was assessed by comparing MVO2 with cardiac work at a wide range of workloads. In the post-ischaemia heart, dobutamine (5 μg kg(-1)  min(-1) ) increased cardiac output (CO) by increasing HR from 102 ± 21 to 131 ± 16 bpm (beats per min; P efficiency. Similar findings on efficiency and LV function were also seen using an ex vivo working mouse heart protocol. A combined infusion of dobutamine and ivabradine had a neutral effect on post-ischaemia LV efficiency and increased left ventricular output without an increase in HR. © 2016 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

  10. Non-invasive in vivo imaging of myocardial apoptosis and necrosis

    Energy Technology Data Exchange (ETDEWEB)

    Flotats, Albert; Carrio, Ignasi [Hospital de la Santa Creu i Sant Pau, Barcelona (Spain)

    2003-04-01

    Myocardial necrosis plays an important role in the pathogenesis of various cardiovascular disorders and can result from different myocardial insults. Its non-invasive identification and localisation therefore may help in the diagnosis of these disorders, as well as in prognosis and assessment of treatment response. Apoptosis, or programmed cell death, is important in the spectrum of myocardial damage since it is gradually becoming more apparent that cell death may begin as apoptosis and not as necrosis. First attempts to directly visualise the area of myocardial necrosis were based on recognition of myocardial infarction with ''hot spot imaging agents'' in patients with chest pain. Since then, the study of myocardial necrosis with gamma imaging agents has gone beyond the detection of myocardial infarction, and attempts have been made to diagnose other cardiovascular disorders associated with cardiac cell death such as heart transplant rejection, myocarditis, cardiotoxicity and cardiomyopathies. Traditionally, two hot spot imaging agents have been used for the detection of myocardial necrosis, {sup 99m}Tc-pyrophosphate and {sup 111}In-antimyosin. In addition, preliminary studies have demonstrated promising results with {sup 99m}Tc-glucarate. Recently, {sup 99m}Tc-annexin V has been successfully used for non-invasive gamma imaging of apoptosis after acute myocardial infarction, acute myocardial ischaemia, acute cardiac allograft rejection and malignant intracardiac tumours. This review article focusses on the characteristics of these different myocardial necrotic and apoptotic markers and compares their role in the assessment of myocardial damage. (orig.)

  11. Mesenteric ischaemia after endovascular coiling of ruptured cerebral aneurysms.

    LENUS (Irish Health Repository)

    Kamel, M H

    2012-02-03

    Three patients were referred to a national neurosurgical centre following CT evidence of subarachnoid haemorrhage. The three patients, who were referred from different institutions within a seven week period, were Fisher grade 3 and WFNS Grade I at all times. Angiography showed a PCOM aneurysm in one case, a ruptured Basilar tip aneurysm and an unruptured ACOM aneurysm in another case, and an ACOM aneurysm in the third case. It was decided that the aneurysms were suitable for endovascular coiling. These patients had unremarkable intraoperative catheterizations and coiling but subsequently deteriorated post-operatively due to mesenteric ischaemia. Two patients required colectomy for mesenteric ischaemia, and the third arrested secondary to sepsis from bowel perforation. We discuss the various causes that may explain this association, and we alert the neurosurgical community for this complication which has not been reported before.

  12. Systematic administration of B vitamins attenuates neuropathic hyperalgesia and reduces spinal neuron injury following temporary spinal cord ischaemia in rats.

    Science.gov (United States)

    Yu, C-Z; Liu, Y-P; Liu, S; Yan, M; Hu, S-J; Song, X-J

    2014-01-01

    B vitamins have been demonstrated to be effective in treating chronic pain due to peripheral nerve injury. We investigated whether B vitamins could alleviate neuropathic pain and reduce neuron injury following temporary ischaemia in a rat model of spinal cord ischaemia-reperfusion injury (SCII). SCII was produced by transiently blocking the unilateral lumbar arteries in adult male Sprague-Dawley rats. Behavioural and neurochemical signs of neuropathic pain and spinal neuron injury were analysed with and without B vitamin treatment. SCII caused behavioural thermal hyperalgesia and mechanical allodynia and neurochemical alterations, including increased expression of the vanilloid receptor 1 (VR1) and induction of c-Fos, as well as activation of the astrocytes and microglial cells in the spinal cord. Repetitive systemic administration of vitamin B complex (B1/B6/B12 at 33/33/0.5 mg/kg, i.p., daily, for 7-14 consecutive days) significantly reduced thermal hyperalgesia and the increased expression of VR1 and c-Fos, as well as activation of the astrocytes and microglial cells. SCII caused a dramatic decrease of the expression of the rate-limiting enzyme glutamic acid decarboxylase-65 (GAD65), which synthesizes γ-aminobutyric acid (GABA) in the axonal terminals, and β-III-tubulin, and also caused loss of Nissl bodies in the spinal cord. These alterations were largely prevented and rescued by the B vitamin treatment. These findings support the idea that the B vitamins are capable of neuroprotection and antinociception during spinal cord injury due to temporary ischaemia. Rescuing the loss of inhibitory GABAergic tone may reduce spinal central sensitization and contribute to B vitamin-induced analgesia. © 2013 European Pain Federation - EFIC®

  13. Stress distribution prevents ischaemia and bone resorption in residual ridge.

    Science.gov (United States)

    Maruo, Yukinori; Nishigawa, Goro; Irie, Masao; Oka, Morihiko; Hara, Tetsuya; Suzuki, Kazuomi; Minagi, Shogo

    2010-11-01

    Intensive mechanical stress and/or inflammation are known to induce alveolar bone resorption. This study investigated whether a distribution of mechanical stress would reduce residual ridge resorption or improve ischaemia. Thirty rats were divided into six experimental groups (n=5). The control group received no intentional stimulation, but rats in the experimental groups wore denture stimulators made of acrylic resin or a soft lining material. The stimulator transmitted masticatory pressure to the rats' palates for four weeks. The four types of soft lining materials investigated in this study dispersed the applied pressure, with compressive stress ranging from 20.8 to 90.8kPa. Volumes of blood flow and bone resorption of denture foundations were measured every week for 4 weeks. Statistical evaluation of these results was performed using two-way ANOVA and Holm-Sidak test within 5% error limits. Non-viscoelastic material clearly induced bone resorption and ischaemia of denture foundations, while viscoelastic materials reduced these phenomena to different extents according to their viscoelastic properties. Ischaemia in the alveolar ridge preceded residual ridge resorption, because the amount of residual ridge resorption and blood flow rate showed a simple linear regression. Animal model of this study suggested that a distribution or reduction of mechanical stress could improve blood flow and decrease alveolar ridge resorption. Copyright © 2010 Elsevier Ltd. All rights reserved.

  14. Clinical indications for Thallium-201 myocardial perfusion scanning

    International Nuclear Information System (INIS)

    Dunn, R.J.; Kelly, D.T.

    1982-01-01

    Thallium-201 myocardial perfusion scanning can assess regional myocardial perfusion non-invasively. As it is both time-consuming and expensive its use should be restricted to specific diagnostic problems. The clinical indications in known or suspected coronary artery disease are reviewed. In suspected coronary artery disease thallium scanning is most useful in patients with chest pain when the exercise ECG is uninterpretable, in men with probable angina but a negative exercise ECG, or conversely a positive exercise ECG without typical angina, and in women with probable angina and either a positive or a negative exercise ECG. In known coronary artery disease, thallium scanning may help determine the functional significance of a coronary obstruction found at angiography and may determine the site of myocardial ischaemia when multiple obstructions are present

  15. : Myocardial Perfusion

    OpenAIRE

    Dacher, Jean-Nicolas; Lefebvre, V.; Dubourg, Bernard; Deux, Jean-François; Caudron, Jérôme

    2013-01-01

    International audience; The analysis of myocardial perfusion is a key step in the cardiac MRI examination. In routine work, this exploration carried out at rest is based on the qualitative first pass study of gadolinium with an ECG-triggered saturation recovery bFFE sequence. In view of recent knowledge, the analysis of the myocardial perfusion under vasodilator stress may be carried out by scintigraphy or MRI, the latter benefiting from the absence of exposure to ionizing rays and a lower co...

  16. Preconditioning and tolerance against cerebral ischaemia

    Science.gov (United States)

    Dirnagl, Ulrich; Becker, Kyra; Meisel, Andreas

    2009-01-01

    Neuroprotection and brain repair in patients after acute brain damage are still major unfulfilled medical needs. Pharmacological treatments are either ineffective or confounded by adverse effects. Consequently, endogenous mechanisms by which the brain protects itself against noxious stimuli and recovers from damage are being studied. Research on preconditioning, also known as induced tolerance, over the past decade has resulted in various promising strategies for the treatment of patients with acute brain injury. Several of these strategies are being tested in randomised clinical trials. Additionally, research into preconditioning has led to the idea of prophylactically inducing protection in patients such as those undergoing brain surgery and those with transient ischaemic attack or subarachnoid haemorrhage who are at high risk of brain injury in the near future. In this Review, we focus on the clinical issues relating to preconditioning and tolerance in the brain; specifically, we discuss the clinical situations that might benefit from such procedures. We also discuss whether preconditioning and tolerance occur naturally in the brain and assess the most promising candidate strategies that are being investigated. PMID:19296922

  17. Myocardial infarction and nocturnal hypoxaemia

    Directory of Open Access Journals (Sweden)

    Penčić Biljana

    2007-01-01

    Full Text Available Introduction: There is an increased risk of cardiovascular morbidity and mortality in patients with nocturnal intermittent hypoxaemia. Objecive. The aim of this study was to evalute the influence of nocturnal hypoxaemia on ventricular arrhythmias and myocardial ischaemia in patients with myocardial infarction (MI. Method. We studied 77 patients (55.8±7.9 years with MI free of complications, chronic pulmonary diseases, abnormal awake blood gases tension. All patients underwent overnight pulse oximetry and 24-hour electrocardiography. Patients were divided into two groups according to nocturnal hypoxaemia. Total number of ventricular premature complex (VPC; maximal VPC/h; incidence of VPC Lown class>2 and occurrence of ST-segment depression were analyzed for nocturnal (10 PM to 6 AM, daytime (6 AM to 22 PM periods and for the entire 24 hours. Results. Both groups were similar in age, gender, standard risk factors, myocardial infarction size and did not differ in VPC during the analyzed periods. The number of nocturnal maximal VPC/h was insignificantly greater in group 1 (with hypoxaemia compared to group 2 (without hypoxaemia, (p=0.084. Maximal VPC/h did not differ significantly either for daytime or for 24 hours among the groups. Nocturnal VPC Lown>2 were significantly more frequent in group 1 (25% vs 0%, p=0.002. The incidence of VPC Lown>2 was similar during the daytime, and during 24 hrs in both groups. Occurrence of ST-segment depression did not differ between groups 1 and 2. Conclusion. Nocturnal hypoxaemia was associated with complex nocturnal ventricular arrhythmias in patients with MI. .

  18. ROLE OF ULTRASONOGRAPHY, CONVENTIONAL ANGIOGRAPHY, CT AND CT ANGIOGRAPHY IN ASSESSMENT OF MESENTERIC ISCHAEMIA

    Directory of Open Access Journals (Sweden)

    Reena

    2016-05-01

    Full Text Available AIM The aim of the study was to evaluate efficacy, sensitivity, specificity of ultrasonography, conventional angiography, CT Angiography in mesenteric ischaemia. MATERIALS AND METHODS Prospective study was performed. 35 patients with clinically suspected mesenteric ischaemia were included in the study. The study was conducted from month of November 2013 to August 2015. The patients age ranged from 35 to 70 years (Mean age was 57±11.2 years. All cases met the criteria of acute nontraumatic or chronic abdominal pain and suspected mesenteric vascular ischaemia. All 35 cases were evaluated in surgery department, then underwent USG, conventional angiography, CTA. Out of 20 patients, 2 patients were inconclusive and 4 patients had other findings of abdominal pain. USG and CT angiographic findings were correlated with surgical findings in acute mesenteric ischaemia (AMI cases & conventional angiography in chronic mesenteric ischaemia (CMI cases. RESULT Ultrasonography has lower sensitivity and high specificity. Conventional angiography has moderate sensitivity and high specificity. CT angiography is highly sensitive and specific in detecting mesenteric ischaemia. CONCLUSION Conventional angiography is considered as the gold standard test for patients with acute and chronic mesenteric ischaemia except for hemodynamically unstable patients with acute mesenteric ischaemia. CTA is an emerging diagnostic test with high sensitivity and specificity in the setting of both acute and chronic mesenteric ischaemia and should be considered the first-line imaging test. CT can also accurately assess for other causes of acute and chronic abdominal pain, and it provides excellent anatomic mapping of the mesenteric vasculature, which is essential in the preoperative planning. US of the abdomen with Doppler waveform analysis can depict proximal mesenteric thrombosis and secondary signs of bowel compromise, but it is limited in the diagnosis of distal occlusions

  19. Δ9-Tetrahydrocannabinol (THC) and AM 404 protect against cerebral ischaemia in gerbils through a mechanism involving cannabinoid and opioid receptors

    Science.gov (United States)

    Zani, A; Braida, D; Capurro, V; Sala, M

    2007-01-01

    Background and purpose: It has been suggested that the endocannabinoid system elicits neuroprotection against excitotoxic brain damage. In the present study the therapeutic potential of AM 404 on ischaemia-induced neuronal injury was investigated in vivo and compared with that of the classical cannabinoid receptor type 1 (CB1) agonist, Δ9-tetraydrocannabinol (THC), using a model of transient global cerebral ischaemia in the gerbil. Experimental approach: The effects of AM 404 (0.015–2 mg kg−1) and THC (0.05–2 mg kg−1), given 5 min after ischaemia, were measured from 1 h to 7 days in terms of electroencephalographic (EEG) total spectral power, spontaneous motor activity, memory function, rectal temperature and hippocampal CA1 neuronal count. Key results: Over the dose range tested, AM 404 (2 mg kg−1) and THC (1 mg kg−1) completely reversed the ischaemia-induced behavioural, EEG and histological damage. Only THC (1 and 2 mg kg−1) induced a decrease of body temperature. Pretreatment with the selective CB1 receptor antagonist, AM 251 (1 mg kg−1) and the opioid antagonist, naloxone (2 mg kg−1) reversed the protective effect induced by both AM 404 and THC while the TRPV1 vanilloid antagonist, capsazepine (0.01 mg kg−1), was ineffective. Conclusions and implications: Our findings demonstrate that AM 404 and THC reduce neuronal damage caused by bilateral carotid occlusion in gerbils and that this protection is mediated through an interaction with CB1 and opioid receptors. Endocannabinoids might form the basis for the development of new neuroprotective drugs useful for the treatment of stroke and other neurodegenerative pathologies. PMID:17965746

  20. Myocardial scintigraphy

    International Nuclear Information System (INIS)

    Bunko, Hisashi; Hisada, Kinichi

    1982-01-01

    Among the various methods of image diagnosis of the cardiovascular disorder, nuclear cardiology provides noninvasive means for evaluation of myocardial perfusion as well as morphological and functional informations. In this article, clinical application and image diagnosis of myocardial scintigraphy including Tl-201 myocardial perfusion scintigraphy, single photon emission computed tomography with Tl-201, acute myocardial infarction scintigraphy with Tc-99m-pyrophosphate and Ga-67 imaging of the heart, were discussed. Multiplanar imaging of the heart with Tl-201 after stress and at redistribution was the accepted method for detection and evaluation of the ischemic heart disease. Although it achieved high sensitivity and specificity for ischemic heart disease, detection of the small ischemia and quantation of the regional Tl-201 accumulation were difficult with conventional multiplanar imaging. Application of emission computed tomography improved detectability and quantitativity of the ischemia. However, 7-pinhole tomography did not increase the diagnostic accuracy significantly. It had limited clinical applicability due to poor quantitativity in spite of improved image contrast and its tomographic nature. Advantage and limitation of these tomographic imaging and multiplanar imaging were discussed. Problems and prognostic significance of pyrophosphate imaging of the acute myocardial infarction were also discussed. Visualization of the heart with Ga-67 was helpful for identification of the tumor or inflammation of the heart as well as evaluation of the effect of the therapy. (author)

  1. Static myocardial scintigraphy in pediatrics

    International Nuclear Information System (INIS)

    Gilday, D.L.

    1981-01-01

    Examples are given for the applications of 201 Tl myocardial scintiscanning in prediatries. In this case, a very careful clinical assessment should be made at first and, whenever possible, the non-invasive modalities such as ultrasonography should be preferred. The transient myorcardial ischemia of the newborn is an example which demonstrates best the role that thallium can play in eliminating cardiac catheterization, a much greater radiation-producing and hazardous procedure. (MG)

  2. Integrated prediction of lesion-specific ischaemia from quantitative coronary CT angiography using machine learning

    DEFF Research Database (Denmark)

    Dey, Damini; Gaur, Sara; Ovrehus, Kristian A

    2018-01-01

    OBJECTIVES: We aimed to investigate if lesion-specific ischaemia by invasive fractional flow reserve (FFR) can be predicted by an integrated machine learning (ML) ischaemia risk score from quantitative plaque measures from coronary computed tomography angiography (CTA). METHODS: In a multicentre...

  3. Acute upper arm ischaemia: a rare presentation of non-Hodgkin's lymphoma.

    LENUS (Irish Health Repository)

    Daruwalla, Z J

    2010-12-01

    Digital ischaemia has been sparsely reported in current literature. Its association with lymphomatous conditions has been described in even more exceptional occurrences. We present the first case of upper arm ischaemia associated with non-Hodgkin\\'s lymphoma. A brief literature review of this rare phenomenon is also accompanied with it.

  4. Induction of interleukin-1β mRNA after focal cerebral ischaemia in the rat

    NARCIS (Netherlands)

    Buttini, M.; Sauter, A.; Boddeke, H.W.G.M.

    1994-01-01

    The expression of interleukin-1β (IL-1β) mRNA in the brain in response to cerebral ischaemia in rats was examined using in situ hybridization histochemistry. Focal cerebral ischaemia was induced in spontaneously hypertensive rats by permanent occlusion of the left middle cerebral artery (MCAO).

  5. Prevalence and prediction of silent ischaemia in diabetes mellitus: a population-based study

    DEFF Research Database (Denmark)

    May, O; Arildsen, H; Damsgaard, E M

    1997-01-01

    OBJECTIVES: The aim of the study was to estimate the prevalence of silent ischaemia in diabetic subjects in the population, to compare the prevalence of silent ischaemia in diabetics and non-diabetics and to attempt to predict the presence of silent ischaemia in diabetic subjects. METHODS: A random...... was registered simultaneously with ECG evidence of ischaemia. Individuals with ischaemia, but without angina pectoris, were defined as persons with silent ischaemia. RESULTS: Seventy-four percent of the invited group were included. The observed prevalence of silent ischaemia in diabetics was 13.5% (95% CI = 8.......5-19.8%). No association was found between silent ischaemia and gender (P = 0.83) or diabetes type (P = 0.67). In the group of diabetics who had controls, the prevalence was 11.4%, and among the controls the prevalence was 6.4% (OR = 1.87, one-sided P = 0.079). Systolic blood pressure was highly predictive of silent...

  6. Systematic review of survival after acute mesenteric ischaemia according to disease aetiology

    NARCIS (Netherlands)

    Schoots, I. G.; Koffeman, G. I.; Legemate, D. A.; Levi, M. [=Marcel M.; van Gulik, T. M.

    2004-01-01

    BACKGROUND: Differentiation of acute mesenteric ischaemia on the basis of aetiology is of great importance because of variation in disease progression, response to treatment and outcome. The aim of this study was to analyse the published data on survival following acute mesenteric ischaemia over the

  7. Microvascular reactivity differences between the two legs of patients with unilateral lower limb ischaemia

    NARCIS (Netherlands)

    Ubbink, D. T.; Jacobs, M. J.; Slaaf, D. W.; Tangelder, G. J.; Reneman, R. S.

    1992-01-01

    Posturally induced microvascular constriction in the skin of the leg is disturbed in severe ischaemia. It is unknown whether this disturbance is of local or central origin and whether the stage of ischaemia at which this disturbance occurs differs when the nutritive and thermoregulatory flow levels

  8. Myocardial scintigraphy in acute myocardial infarction

    International Nuclear Information System (INIS)

    Faerestrand, S.

    1984-01-01

    The sensitivity and specificity of 99m Tc-PYP myocardial scintigraphy for detecting an acute myocardial infarction were studied in 39 patients hospitalized because of central chest pain. One myocardial scintigraphic examination was done in each patient between the first and sixth day after the chest pain had started. Twenty-two patients had a myocardial infarction based on history, ECG and enzym values and myocardial scintigraphy was positive in twenty of these. Three patients with left bundle branch block and myocardial infarction all had a positive myocardial scintigram and the one patient with negative ECG and myocardial infarction also had a positive myocardial scintigram. The sensitivity is 91% and the specificity is 91.7% for 99m Tc-PYP myocardial scintigraphy in the detection of acute myocardial infarction. No complications were seen. (Auth.)

  9. MRI in acute cerebral ischaemia: perfusion imaging with superparamagnetic iron oxide in a rat model

    International Nuclear Information System (INIS)

    Forsting, M.; Reith, W.; Doerfler, A.; Kummer, R. von; Hacke, W.; Sartor, K.

    1994-01-01

    An imaging technique capable of detecting ischaemic cerebral injury at an early stage could improve diagnosis in acute or transient cerebral ischaemia. We compared the ability of superparamagnetically contrast-enhanced MRI and conventional T2-weighted MRI to detect ischaemic injury early after unilateral occlusion of the middle cerebral artery in 12 male Wistar rats. Permanent vessel occlusion was achieved by a transvascular approach, which has the advantage of not requiring a craniectom. At 45-60 min after the procedure, the animals had conventional T2-weighted MRI before and after administration of a superparamagnetic contrast agent (iron oxide particles). Unenhanced images were normal in all animals. After administration of iron oxide particles, the presumed ischaemic area was clearly visible, as relatively increased signal, in all animals; this high signal area corresponded to the area of ischaemic brain infarction seen on histological studies. Our results suggest that superparamagnetic iron particles may significantly reduce the interval between an ischaemic insult and the appearance of parenchymal changes on MRI. (orig./UWA)

  10. A decision support system improves the interpretation of myocardial perfusion imaging

    DEFF Research Database (Denmark)

    Tagil, K.; Bondouy, M.; Chaborel, J.P.

    2008-01-01

    PURPOSE: The aim of this study was to investigate the influence of a computer-based decision support system (DSS) on performance and inter-observer variability of interpretations regarding ischaemia and infarction in myocardial perfusion scintigraphy (MPS). METHODS: Seven physicians independently...... with the advice of the DSS showed less inter-observer variability than those made without advice. CONCLUSION: This study shows that a DSS can improve performance and reduces the inter-observer variability of interpretations in myocardial perfusion imaging. Both experienced and, especially, inexperienced...

  11. McConnell's sign in intra-operative acute right ventricle ischaemia: An under-recognized aetiology.

    Science.gov (United States)

    Longo, S A; Echegaray, A; Acosta, C M; Rinaldi, L I; Cabrera Schulmeyer, M C; Olavide Goya, I

    2016-11-01

    Transoesophageal echocardiography (TEE) has become a fundamental tool in modern cardiothoracic anaesthesia. It has an indisputable role in coronary valve surgery and revascularisations with severe impairment of ventricle function. It helps in making diagnoses that can optimise the surgical strategy and to minimal invasively dynamically monitor volaemia and cardiac function during the post-operative period, detecting complications unobservable by other methods. The McConnell sign, visualised using TEE as an akinesis of the right ventricular free wall, with a normal apex motility and enlargement of the right cavities, is characteristic of right ventricular (RV) dysfunction. This sign has a 77% sensitivity and 94% specificity for the diagnosis of acute pulmonary embolism (APE). The case is presented of a 53-year-old man scheduled for aortic valve and ascending aorta replacement surgery, with a history of severe valve aortic stenosis, aortic root and arch aneurysm, and with normal coronary arteries. Post-cardiopulmonary bypass (CBP), the patient presented with haemodynamic instability, with the TEE showing a typical image of the McConnell sign, with no pulmonary hypertension. This enabled making an early diagnosis of acute RV ischaemia, that led to a change in the surgical plan, the performing of coronary revascularisation surgery. As a result, the McConnell sign, which describes the characteristics of RV dysfunction, led to making a differential diagnosis between APE, RV infarction and acute myocardial ischaemia. Copyright © 2016 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

  12. Regional heterogeneity in cardiac sympathetic innervation in acute myocardial infarction: relationship with myocardial oedema on magnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Gimelli, Alessia; Masci, Pier Giorgio; Pasanisi, Emilio Maria; Lombardi, Massimo [Fondazione CNR/Regione Toscana, Pisa (Italy); Liga, Riccardo; Grigoratos, Chrysanthos [University Hospital of Pisa, Pisa (Italy); Marzullo, Paolo [Fondazione CNR/Regione Toscana, Pisa (Italy); Institute of Clinical Physiology, CNR, Pisa (Italy)

    2014-09-15

    To assess the relationships between myocardial structure and function on cardiac magnetic resonance (CMR) imaging and sympathetic tone on {sup 123}I-metaiodobenzylguanidine ({sup 123}I-MIBG) scintigraphy early after myocardial infarction (MI). Ten patients underwent {sup 123}I-MIBG and {sup 99m}Tc-tetrofosmin rest cadmium zinc telluride scintigraphy 4 ± 1 days after MI. The segmental left ventricular (LV) relative radiotracer uptake of both {sup 99m}Tc-tetrofosmin and early {sup 123}I-MIBG was calculated. The day after scintigraphy, on CMR imaging, the extent of ischaemia-related oedema and of myocardial fibrosis (late gadolinium enhancement, LGE) was assessed. Accordingly, the extent of oedema and LGE was evaluated for each segment and segmental wall thickening determined. Based on LGE distribution, LV segments were categorized as ''infarcted'' (56 segments), ''adjacent'' (66 segments) or ''remote'' (48 segments). Infarcted segments showed a more depressed systolic wall thickening and greater extent of oedema than adjacent segments (p < 0.001) and remote segments (p < 0.001). Interestingly, while uptake of {sup 99m}Tc-tetrofosmin was significantly depressed only in infarcted segments (p < 0.001 vs. both adjacent and remote segments), uptake of {sup 123}I-MIBG was impaired not only in infarcted segments (p < 0.001 vs. remote) but also in adjacent segments (p = 0.024 vs. remote segments). At the regional level, after correction for {sup 99m}Tc-tetrofosmin and LGE distribution, segmental {sup 123}I-MIBG uptake (p < 0.001) remained an independent predictor of ischaemia-related oedema. After acute MI the regional impairment of sympathetic tone extends beyond the area of altered myocardial perfusion and is associated with myocardial oedema. (orig.)

  13. Assessment of chest pain in hypertrophic cardiomyopathy using exercise thallium-201 myocardial scintigraphy

    International Nuclear Information System (INIS)

    Pitcher, D.; Wainwright, R.; Maisey, M.; Curry, P.; Sowton, E.

    1980-01-01

    Exercise thallium-201 myocardial scintigraphy was performed in 23 patients with hypertrophic cardiomyopathy. Eighteen patients presented with chest pain which was a persistent symptom in 11. Selective coronary arteriography was performed in 16 patients and showed normal coronary arteries in 15 and insignificant luminal irregularities in one patient. Eighteen patients had abnormal scintigrams. Three had an abnormal distribution of tracer entirely attributable to asymmetric septal hypertrophy, whereas 15 had discrete tracer uptake defects which could not be explained solely by myocardial hypertrophy. In this latter group of patients three scintigraphic patterns were identified: (1) in 10 patients defects were seen in scintigrams immediately after exercise but not in delayed images obtained four to six hours later. Eight of these patients had chest pain. (2) Four patients had uptake defects seen in both initial and delayed images. One patient had chest pain. (3) In three patients, one of whom had chest pain, tracer defects were seen only in delayed images and were not apparent in the initial scintigrams. Chest pain occurred in eight out of 10 patients with scintigraphic evidence of myocardial ischaemia but was present in only three out of 13 patients with non-ischaemic scintigrams. The value of exercise thallium-201 myocardial imaging as a diagnostic technique in hypertrophic cardiomyopathy appears limited. Scintigraphic evidence of regional myocardial ischaemia in the absence of significant coronary artery disease, however, contributes to an understanding of the mechanism of angina production in patients with hypertrophic cardiomyopathy. (author)

  14. DIAGNOSIS AND THERAPY IN TRANSITORY MYOCARDIAL ISCHEMIA

    Directory of Open Access Journals (Sweden)

    Anica Pavlovic

    2008-01-01

    Full Text Available Cardiac dysfunction occurring within subarachnoid hemorrhage named neurogenic stunned myocardium have great impact on intensive care of patients with SAH. Timely diagnosis and treatment of such condition can provide better haemodynamics of damaged brain. The standard follow-up was performed in 30 patients with SAH during two years at the Clinic of Neurosurgery (2005,2006. Serial electrocardiography, echocardiography, as well as laboratory findings of special biomarkers of left ventricular wall motion abnormalities were performed. All patients were treated with Urapidil, Metoprolol, MgSO4 by cheme and ACE inhibitors. Ninety EKG were analyzed in the study, as well as 16 electrocardiographies. The highest levels of CPK, CK-MB and TnI before and after the therapy were also recoded. EKG showed the signs of ischemia in 9 of 30 patients on 1st day and 7 of 30 patients on 3rd day of the therapy. The highest level of CK-MB was present during the 1st day with mean value of 67,80±1,83 IU/L that decreased on 3rd day of therapy with mean value of 66,8±1,83 IU/L, TnI was positive in 16 cases. It showed statistically significant decrease from 0,29 ng/ml till 0,187 ng/ml and p < 0,01. Myocardial ischaemia has been proven to be a very significant complication in SAH. Appropriate treatment of myocardial ischaemia seems to improve systemic haemodynamics, as well as haemodynamics of the damaged brain.

  15. Endothelin-B Receptors and Left Ventricular Dysfunction after Regional versus Global Ischaemia-Reperfusion in Rat Hearts

    Directory of Open Access Journals (Sweden)

    Sofia-Iris Bibli

    2012-01-01

    Full Text Available Background. Endothelin-1 (ET-1 is implicated in left ventricular dysfunction after ischaemia-reperfusion. ETA and ETB receptors mediate diverse actions, but it is unknown whether these actions depend on ischaemia type and duration. We investigated the role of ETB receptors after four ischaemia-reperfusion protocols in isolated rat hearts. Methods. Left ventricular haemodynamic variables were measured in the Langendorff-perfused model after 40- and 20-minute regional or global ischaemia, followed by 30-minute reperfusion. Wild-type (n=39 and ETB-deficient (n=41 rats were compared. Infarct size was measured using fluorescent microspheres after regional ischaemia-reperfusion. Results. Left ventricular dysfunction was more prominent in ETB-deficient rats, particularly after regional ischaemia. Infarct size was smaller (P=0.006 in wild-type (31.5±4.4% than ETB-deficient (45.0±7.3% rats after 40 minutes of regional ischaemia-reperfusion. Although the recovery of left ventricular function was poorer after 40-minute ischaemia-reperfusion, end-diastolic pressure in ETB-deficient rats was higher after 20 than after 40 minutes of regional ischaemia-reperfusion. Conclusion. ETB receptors exert cytoprotective effects in the rat heart, mainly after regional ischaemia-reperfusion. Longer periods of ischaemia suppress the recovery of left ventricular function after reperfusion, but the role of ETB receptors may be more important during the early phases.

  16. Effect of monoamine oxidase inhibitors on ischaemia/reperfusion-induced acute kidney injury in rats.

    Science.gov (United States)

    Tsutsui, Hidenobu; Shimokawa, Takaomi; Miura, Takeshi; Takama, Masashi; Nishinaka, Toru; Terada, Tomoyuki; Yamagata, Masayo; Yukimura, Tokihito

    2018-01-05

    Increases in renal sympathetic nerve activity during ischaemia and renal venous norepinephrine levels after reperfusion play important roles in the development of ischaemia/reperfusion-induced acute kidney injury. In the present study, we examined the effect of isatin, an endogenous monoamine oxidase inhibitor, on renal venous norepinephrine levels, superoxide production after reperfusion, and ischaemia/reperfusion-induced acute kidney injury. Ischaemia/reperfusion-induced acute kidney injury was accomplished by clamping the left renal artery and vein for 45min, followed by reperfusion, 2 weeks after contralateral nephrectomy. Renal superoxide production and norepinephrine overflow were elevated and significant renal tissue damage was observed following ischaemia/reperfusion injury. Intravenous injection of isatin (10mg/kg) at 5min before ischaemia increased the renal venous plasma norepinephrine level after reperfusion and aggravated ischaemia/reperfusion-induced renal dysfunction and histological damage. The excessive superoxide production after reperfusion was significantly suppressed by isatin administration, indicating that the inhibition of oxidative deamination effectively suppressed superoxide production. These data suggest that the exacerbation effect of isatin is associated, at least in part, with increased norepinephrine levels but not with superoxide production. To the best of our knowledge, this is the first report of isatin involvement in the pathogenesis and/or development of acute kidney injury. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Ischaemia/reperfusion induced cardiac stem cell homing to the injured myocardium by stimulating stem cell factor expression via NF-kappaB pathway.

    Science.gov (United States)

    Guo, Junli; Jie, Wei; Kuang, Dong; Ni, Juan; Chen, Duoen; Ao, Qilin; Wang, Guoping

    2009-06-01

    Ischaemia/reperfusion (I/R) is a major cause of heart failure. Recently cardiac stem cells (CSCs) were proposed as the most appropriate cell type for heart disease therapy. However, it is still unclear whether I/R can stimulate the CSCs homing to the injured myocardium. Male Sprague-Dawley rats were subjected to a 30-min ischaemia followed by reperfusion of different intervals. RT-PCR, western blotting and immunohistochemistry were performed to detect stem cell factor (SCF) expression at mRNA and protein levels respectively. Activation of nuclear factor-kappaB (NF-kappaB) was determined by electrophoretic mobility shift assay. To assess the homing of CSCs in vivo, BrdU-labelled CSCs were injected into AV-groove before induction of ischaemia and examined by immunofluorescent staining in the injured myocardium after I/R. From day 3 to day 6 after reperfusion, the accumulation of CSCs was significantly elevated in the injured area, which was matched with the increased SCF expression during I/R. Pretreatment of rats with NF-kappaB inhibitor, N-acetyl-L-cysteine (NAC) not only suppressed NF-kappaB activation induced by I/R but also attenuated SCF expression. Further analysis revealed that I/R induced phosphorylation of IkappaBalpha after 15 min of reperfusion, and the raised phosphor-IkappaBalpha returned to the basal level at 2 h of reperfusion. In simulated I/R(SI/R) in vitro, it enhanced NF-kappaB activation and SCF expression in cultured neonatal rat cardiomyocytes, which was markedly inhibited by NF-kappaB decoy oligodeoxynucleotide or NAC. Taken together, our results demonstrated that I/R induced CSCs homing to the injured myocardium by stimulating myocardial SCF expression via activation of NF-kappaB.

  18. Ischaemia/reperfusion induced cardiac stem cell homing to the injured myocardium by stimulating stem cell factor expression via NF-κB pathway

    Science.gov (United States)

    Guo, Junli; Jie, Wei; Kuang, Dong; Ni, Juan; Chen, Duoen; Ao, Qilin; Wang, Guoping

    2009-01-01

    Ischaemia/reperfusion (I/R) is a major cause of heart failure. Recently cardiac stem cells (CSCs) were proposed as the most appropriate cell type for heart disease therapy. However, it is still unclear whether I/R can stimulate the CSCs homing to the injured myocardium. Male Sprague–Dawley rats were subjected to a 30-min ischaemia followed by reperfusion of different intervals. RT-PCR, western blotting and immunohistochemistry were performed to detect stem cell factor (SCF) expression at mRNA and protein levels respectively. Activation of nuclear factor-κB (NF-κB) was determined by electrophoretic mobility shift assay. To assess the homing of CSCs in vivo, BrdU-labelled CSCs were injected into AV-groove before induction of ischaemia and examined by immunofluorescent staining in the injured myocardium after I/R. From day 3 to day 6 after reperfusion, the accumulation of CSCs was significantly elevated in the injured area, which was matched with the increased SCF expression during I/R. Pretreatment of rats with NF-κB inhibitor, N-acetyl-l-cysteine (NAC) not only suppressed NF-κB activation induced by I/R but also attenuated SCF expression. Further analysis revealed that I/R induced phosphorylation of IκBα after 15 min of reperfusion, and the raised phosphor-IκBα returned to the basal level at 2 h of reperfusion. In simulated I/R(SI/R) in vitro, it enhanced NF-κB activation and SCF expression in cultured neonatal rat cardiomyocytes, which was markedly inhibited by NF-κB decoy oligodeoxynucleotide or NAC. Taken together, our results demonstrated that I/R induced CSCs homing to the injured myocardium by stimulating myocardial SCF expression via activation of NF-κB. PMID:19563618

  19. Inhibition of delta-protein kinase C by delcasertib as an adjunct to primary percutaneous coronary intervention for acute anterior ST-segment elevation myocardial infarction: results of the PROTECTION AMI Randomized Controlled Trial

    NARCIS (Netherlands)

    Lincoff, A.M.; Roe, M.; Aylward, P.; Galla, J.; Rynkiewicz, A.; Guetta, V.; Zelizko, M.; Kleiman, N.; White, H.; McErlean, E.; Erlinge, D.; Laine, M.; Ferreira, J.M. Dos Santos; Goodman, S.; Mehta, S.; Atar, D.; Suryapranata, H.; Jensen, S.E.; Forster, T.; Fernandez-Ortiz, A.; Schoors, D.; Radke, P.; Belli, G.; Brennan, D.; Bell, G.; Krucoff, M.; et al.,

    2014-01-01

    AIMS: Delcasertib is a selective inhibitor of delta-protein kinase C (delta-PKC), which reduced infarct size during ischaemia/reperfusion in animal models and diminished myocardial necrosis and improved reperfusion in a pilot study during primary percutaneous coronary intervention (PCI) for ST

  20. Acute ischaemias as a result of vasospasm following thrombosis prophylaxis with Dihydroergotamine/Heparin

    International Nuclear Information System (INIS)

    Meybier, H.; Kraemer, K.L.; Maeder, N.; Allenberg, J.R.; Kretzschmar, U.

    1987-01-01

    Vasospastic reactions with ischaemia following combined thrombosis prophylaxis with dihydroergotamine and heparin were reported in literature several times. This article reports 3 cases involving ischaemia following traumas to the limb, and 2 cases with ischaemia developing after surgical traumas. Acute renal insufficiency was observed in a patient with spasms of the renal arteries for the first time who sustained renal insufficiency requiring dialysis as a late sequela. Though rare, thromboembolism prophylaxis using dihydroergotamine/heparin may cause serious sequelae; hence, any combined thrombosis prophylaxis with require a critical indication. (orig.) [de

  1. Intracoronary and systemic melatonin to patients with acute myocardial infarction

    DEFF Research Database (Denmark)

    Halladin, Natalie L; Busch, Sarah Ekeløf; Jensen, Svend Eggert

    2014-01-01

    reperfusion. The endogenous hormone, melatonin, works as an antioxidant and could potentially minimise the ischaemia-reperfusion injury. Given intracoronarily, it enables melatonin to work directly at the site of reperfusion. We wish to test if melatonin, as an antioxidant, can minimise the reperfusion injury......-point is the Myocardial Salvage Index assessed by cardiovascular magnetic resonance imaging on day 4 (± 1) after pPCI. The secondary end-points are high-sensitivity troponin, creatinekinase myocardial band and clinical events. CONCLUSION: The aim of the IMPACT trial is to evaluate the effect of melatonin on reperfusion...... injuries following pPCI. Owing to its relatively non-toxic profile, melatonin is an easily implementable drug in the clinical setting, and melatonin has the potential to reduce morbidity in patients with AMI. FUNDING: This study received no financial support from the industry. TRIAL REGISTRATION: www...

  2. Secondary prevention with calcium antagonists after acute myocardial infarction

    DEFF Research Database (Denmark)

    Hansen, J F

    1992-01-01

    and preventing reinfarction, nevertheless demonstrated pronounced differences between the 3 drugs. Nifedipine had no effect on reinfarction or death. Diltiazem had no overall effect but prevented first reinfarction or cardiac death (cardiac events) in patients without heart failure, and increased cardiac events......Experimental studies have demonstrated that the 3 calcium antagonists nifedipine, diltiazem, and verapamil have a comparable effect in the prevention of myocardial damage during ischaemia. Secondary prevention trials after acute myocardial infarction, which aimed at improving survival...... in patients with heart failure before randomisation. Verapamil prevented first reinfarction or death (major events); the most pronounced effect was found in patients without heart failure before randomisation. Verapamil did not have detrimental effects in patients treated for heart failure before...

  3. Transient analyzer

    International Nuclear Information System (INIS)

    Muir, M.D.

    1975-01-01

    The design and design philosophy of a high performance, extremely versatile transient analyzer is described. This sub-system was designed to be controlled through the data acquisition computer system which allows hands off operation. Thus it may be placed on the experiment side of the high voltage safety break between the experimental device and the control room. This analyzer provides control features which are extremely useful for data acquisition from PPPL diagnostics. These include dynamic sample rate changing, which may be intermixed with multiple post trigger operations with variable length blocks using normal, peak to peak or integrate modes. Included in the discussion are general remarks on the advantages of adding intelligence to transient analyzers, a detailed description of the characteristics of the PPPL transient analyzer, a description of the hardware, firmware, control language and operation of the PPPL transient analyzer, and general remarks on future trends in this type of instrumentation both at PPPL and in general

  4. Inferior ST-Elevation Myocardial Infarction Associated with Takotsubo Cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Oliver Koeth

    2010-01-01

    Full Text Available Takotsubo cardiomyopathy (TCM is usually characterized by transient left ventricular apical ballooning. Due to the clinical symptoms which include chest pain, electrocardiographic changes, and elevated myocardial markers, Takotsubo cardiomyopathy is frequently mimicking ST-elevation myocardial infarction in the absence of a significant coronary artery disease. Otherwise an acute occlusion of the left anterior descending coronary artery can produce a typical Takotsubo contraction pattern. ST-elevation myocardial infarction (STEMI is frequently associated with emotional stress, but to date no cases of STEMI triggering TCM have been reported. We describe a case of a female patient with inferior ST-elevation myocardial infarction complicated by TCM.

  5. Addition of atropine to submaximal exercise stress testing in patients evaluated for suspected ischaemia with SPECT imaging: a randomized, placebo-controlled trial

    Energy Technology Data Exchange (ETDEWEB)

    Manganelli, Fiore; Sauro, Rosario; Di Lorenzo, Emilio; Rosato, Giuseppe [San Giuseppe Moscati Hospital, Department of Cardiology and Heart Surgery, Avellino (Italy); Spadafora, Marco; Varrella, Paola; Peluso, Giuseppina [San Giuseppe Moscati Hospital, Nuclear Medicine Unit, Avellino (Italy); Daniele, Stefania [Institute of Diagnostic and Nuclear Development (SDN), Naples (Italy); Cuocolo, Alberto [Institute of Diagnostic and Nuclear Development (SDN), Naples (Italy); University Federico II, Department of Biomorphological and Functional Sciences, Naples (Italy); National Council of Research, Institute of Biostructures and Bioimages, Naples (Italy)

    2011-02-15

    To evaluate the effects of the addition of atropine to exercise testing in patients who failed to achieve their target heart rate (HR) during stress myocardial perfusion imaging with single-photon emission computed tomography (SPECT). The study was a prospective, randomized, placebo-controlled design. Patients with suspected or known coronary artery disease who failed to achieve a target HR ({>=}85% of maximal predicted HR) during exercise SPECT imaging were randomized to receive intravenous atropine (n = 100) or placebo (n = 101). The two groups of patients did not differ with respect to demographic or clinical characteristics. A higher proportion of patients in the atropine group achieved the target HR compared to the placebo group (60% versus 3%, p < 0.0001). SPECT imaging was abnormal in a higher proportion of patients in the atropine group as compared to the placebo group (57% versus 42%, p < 0.05). Stress-induced myocardial ischaemia was present in more patients in the atropine group as compared to placebo (47% versus 29%, p < 0.01). In both groups of patients, no major side effects occurred. The addition of atropine at the end of exercise testing is more effective than placebo in raising HR to adequate levels, without additional risks of complications. The use of atropine in patients who initially failed to achieve their maximal predicted HR is associated with a higher probability of achieving a diagnostic myocardial perfusion study. (orig.)

  6. Thallium-201 exercise myocardial imaging to evaluate myocardial perfusion after coronary artery bypass surgery

    International Nuclear Information System (INIS)

    Hirzel, H.O.; Nuesch, K.; Sialer, G.; Horst, W.; Krayenbuehl, H.P.

    1980-01-01

    To assess the usefulness of thallium-201 exercise scintigraphy in evaluating myocardial perfusion after coronary artery bypass surgery, imaging was performed after submaximal bicycle ergometry and at rest in 54 patients before and within 24 +- 10 (SD) weeks after operation. Scintigraphy identified 8 out of 20 patients who were symptom free after operation and showed normal exercise electrocardiograms as still having exercise-induced ischaemia and thus as having not truly benefited from the surgical intervention. In contrast, improvement in perfusion was documented in 17 out of 31 patients despite further complaints of chest pain and persistence of a pathological exercise electrocardiogram in 6 of them. Bypass graft patency rate paralleled the scintigraphic findings in the 35 patients who were restudied arteriographically. It was concluded that thallium-201 exercise scintigraphy is a useful technique to document changes in regional perfusion after surgery and is definitely superior to the clinical evaluation of patients including the exercise electrocardiogram. (author)

  7. Near-infrared spectroscopy in the routine diagnostic work-up of patients with leg ischaemia

    NARCIS (Netherlands)

    Ubbink, D. T.; Koopman, B.

    2006-01-01

    OBJECTIVE: To examine the reproducibility and clinical applicability of near-infrared spectroscopy (NIRS) in patients with leg ischaemia. DESIGN: Prospective comparative diagnostic study. MATERIALS AND METHODS: Routinely measured peripheral blood pressure and microcirculatory parameters were

  8. The value of non-invasive techniques for the assessment of critical limb ischaemia

    NARCIS (Netherlands)

    Ubbink, D. T.; Tulevski, I. I.; den Hartog, D.; Koelemay, M. J.; Legemate, D. A.; Jacobs, M. J.

    1997-01-01

    OBJECTIVE: The European Consensus Document (ECD) defines critical ischaemia (CI) according to clinical (Fontaine) and blood pressure parameters. However, clinical symptoms may be non-specific and CI may exist without severely reduced blood pressures. This study prospectively investigated the

  9. Renal blood flow and metabolism after cold ischaemia: peroperative measurements in patients with calculi

    DEFF Research Database (Denmark)

    Petersen, H K; Henriksen, Jens Henrik Sahl

    1984-01-01

    .01) immediately after re-established perfusion and 36% (P less than 0.02) 30 min later. In one additional patient, who had a short warm ischaemia (8 min), the flow pattern was the same. As arterial pressure remained constant, the reduced RBF signifies an increased renal vascular resistance. Renal O2-uptake......Peroperative measurements of renal blood flow (RBF), renal O2-uptake, and renal venous lactate/pyruvate (L/P) ratio were performed before and after a period of 30-71 min of hypothermic (10-15 degrees C) renal ischaemia in nine patients, undergoing surgery for renal calculi. Before ischaemia, RBF...... and renal venous L/P ratio were almost constant, indicating no significant anaerobic processes being involved in the flow response. None of the patients showed any signs of reactive hyperaemia. It is concluded that hypothermic renal ischaemia may be followed by an increased renal vascular resistance even...

  10. Functional significance of coronary collateral circulation during dynamic exercise evaluated by thallium-201 myocardial scintigraphy

    International Nuclear Information System (INIS)

    Wainwright, R.J.; Maisey, M.N.; Edwards, A.C.; Sowton, E.

    1980-01-01

    Sixty-five patients with angiographically documented coronary artery disease were investigated by thallium-201 ( 201 Tl) scintigraphy to determine the role of the collateral circulation during dynamic exercise. Fifty-three patients had complete proximal occlusion of at least one major coronary artery. One patient had total occlusion of all three major coronary arteries. Sixty-four collateral channels were identified, graded, and compared with corresponding regions of the myocardial scintigram. Tracer uptake was also graded and classified as various degrees of protection from ischaemia. A significant correlation between good collaterals with complete protection and poor or absent collaterals with no protection was noted. Seventeen patients (20 occluded vessels) had total coronary occlusion without myocardial infarction. Collaterals conferred protection in 9/15 occlusions whereas no protection was seen in five occlusions without collaterals. There was no difference in the protective role of homocoronary and heterocoronary collateral vessels. Hypertrophy of the first septal left anterior descending perforator conferred significant protection from ischaemia in contrast to bridging collaterals and ghosting. During exercise the right coronary bed is preferentially protected from ischaemia, in contrast to the left anterior descending territory. This probably reflects the direction of a transmural flow gradient between left and right ventricles during exercise. (author)

  11. Lack of MG53 in human heart precludes utility as a biomarker of myocardial injury or endogenous cardioprotective factor.

    Science.gov (United States)

    Lemckert, Frances A; Bournazos, Adam; Eckert, Daniel M; Kenzler, Manuel; Hawkes, Joanne M; Butler, Tanya L; Ceely, Bradley; North, Kathryn N; Winlaw, David S; Egan, Jonathan R; Cooper, Sandra T

    2016-05-15

    Mitsugumin-53 (MG53/TRIM72) is an E3-ubiquitin ligase that rapidly accumulates at sites of membrane injury and plays an important role in membrane repair of skeletal and cardiac muscle. MG53 has been implicated in cardiac ischaemia-reperfusion injury, and serum MG53 provides a biomarker of skeletal muscle injury in the mdx mouse model of Duchenne muscular dystrophy. We evaluated the clinical utility of MG53 as a biomarker of myocardial injury. We performed Langendorff ischaemia-reperfusion injury on wild-type and dysferlin-null murine hearts, using dysferlin deficiency to effectively model more severe outcomes from cardiac ischaemia-reperfusion injury. MG53 released into the coronary effluent correlated strongly and significantly (r = 0.79-0.85, P heart surgery, the first study of MG53 release with myocardial injury in humans. Unexpectedly, we reveal although MG53 is robustly expressed in rat and mouse hearts, MG53 is scant to absent in human, ovine, or porcine hearts. Absence of MG53 in 11 human heart specimens was confirmed using three separate antibodies to MG53, each subject to epitope mapping and confirmed immunospecificity using MG53-deficient muscle cells. MG53 is an effective biomarker of myocardial injury and dysfunction in murine hearts. However, MG53 is not expressed in human heart and therefore does not hold utility as a clinical biomarker of myocardial injury. Although cardioprotective roles for endogenous myocardial MG53 cannot be extrapolated from rodents to humans, potential therapeutic application of recombinant MG53 for myocardial membrane injury prevails. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  12. Influence of acute glycaemic level on measures of myocardial infarction in non-diabetic pigs.

    Science.gov (United States)

    Diemar, Sarah S; Sejling, Anne-Sophie; Iversen, Kasper K; Engstrøm, Thomas; Honge, Jesper L; Tønder, Niels; Vejlstrup, Niels; Idorn, Manja; Ekström, Kathrine; Pedersen-Bjergaard, Ulrik; Thorsteinsson, Birger; Dalsgaard, Morten

    2015-01-01

    Patients with diabetes are at increased risk of experiencing myocardial infarction. The influence of the prevailing plasma glucose level on infarction and mortality after acute ischaemia is however unknown. The aim was to study the effect of the acute plasma glucose level on the myocardial infarction size in a closed-chest pig model. 38 non-diabetic pigs were randomised to hypoglycaemic (1.8-2.2 mmol/l; n = 15), normoglycaemic (5-7 mmol/l; n = 12) or hyperglycaemic glucose clamping (22-23 mmol/l; n = 11). After 30 min within glucose target myocardial infarction was induced for 30 min followed by reperfusion for 120 min. Hereafter the heart was double-stained to delineate infarction from viable tissue within the area at risk. Mean infarction size was 201 ± 35 mm(2) (mean ± SEM) in the hypoglycaemic group, 154 ± 40 mm(2) in the normoglycaemic group and 134 ± 40 mm(2) in the hyperglycaemic group, with no differences in infarction size, infarct/area at risk ratio or troponin T levels between the groups. There was no difference in incidence of ventricular fibrillation or mortality between the groups. No statistically significant associations were observed between the acute glycaemic level and measures of myocardial infarction, rates of ventricular fibrillation and subsequent premature death in the setting of acute ischaemia and reperfusion.

  13. 'Les ictus amnésiques' and transient global amnesia.

    Science.gov (United States)

    Pearce, J M S; Bogousslavsky, Julien

    2009-01-01

    In March 1909, R. Benon was probably the first to report a typical case of what we now call transient global amnesia. In 1956, Bender, and independently, Guyotat and Courjon described clinical and epidemiological features of transient amnesic attacks. The condition achieved general recognition after the term transient global amnesia (TGA) was introduced by Fisher and Adams in 1958. Their historic work is the main focus of this review. They reported 17 patients, with an abrupt anterograde amnesia of short duration. Classification and criteria are outlined. Various aetiologies have been postulated, but although TGA remains a clinically distinct syndrome, usually with a good prognosis, evidence of neither ischaemia nor epilepsy is demonstrable in most patients. Theories of jugular venous reflux may be relevant in some but probably not in most cases of this heterogeneous disorder. Copyright 2009 S. Karger AG, Basel.

  14. Chronic intestinal ischaemia: measurement of the total splanchnic blood flow.

    Science.gov (United States)

    Zacho, Helle D

    2013-04-01

    A redundant collateral network between the intestinal arteries is present at all times. In case of ischaemia in the gastrointestinal tract, the collateral blood supply can develop further, thus accommodating the demand for oxygen even in the presence of significant stenosis or occlusion of the intestinal arteries without clinical symptoms of intestinal ischaemia. Symptoms of ischemia develop when the genuine and collateral blood supply no longer can accommodate the need for oxygen. Atherosclerosis is the most common cause of obliteration in the intestinal arteries. In chronic intestinal ischaemia (CII), the fasting splanchnic blood flow (SBF) is sufficient, but the postprandial increase in SBF is inadequate and abdominal pain will therefore develop in relation to food intake causing the patient to eat smaller meals at larger intervals with a resulting weight loss. Traditionally, the CII-diagnosis has exclusively been based upon morphology (angiography) of the intestinal arteries; however, substantial discrepancies between CII-symptoms and the presence of atherosclerosis/stenosis in the intestinal arteries have been described repeatedly in the literature impeding the diagnosis of CII. This PhD thesis explores a method to determine the total SBF and its potential use as a diagnostic tool in patients suspected to suffer from CII. The SBF can be measured using a continuous infusion of a tracer and catheterisation of a hepatic vein and an artery. By measuring the SBF before and after a standard meal it is possible to assess the ability or inability to enhance the SBF and thereby diagnosing CII. In Study I, measurement of SBF was tested against angiography in a group of patients suspected to suffer from CII due to pain and weight loss. A very good agreement between the postprandial increase in SBF and angiography was found. The method was validated against a well-established method independent of the hepatic extraction of tracer using pAH in a porcine model (study II

  15. Nitrogen-13-labeled ammonia for myocardial imaging

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, W.F.; Fill, H.R.; Harper, P.V.

    1977-01-01

    Cyclotron-produced nitrogen-13 (half-life 10 min), as labeled ammonia (/sup 13/NH/sub 4//sup +/), has been evaluated as a myocardial perfusion imaging agent. The regional myocardial uptake of /sup 13/NH/sub 4//sup +/ has been shown to be proportional to regional tissue perfusion in animal studies. Intravenously administered /sup 13/NH/sub 4//sup +/ is rapidly cleared from the circulation, being extracted by the liver (15 percent), lungs, myocardium (2 percent--4 percent), brain, kidney, and bladder. Myocardial ammonia is metabolized mainly to glutamine via the glutamine synthetase pathway. Pulmonary uptake is substantial, but usually transient, except in smokers where clearance may be delayed. The positron annihilation irradiation (511 keV) of /sup 13/N may be imaged with a scintillation camera, using either a specially designed tungsten collimator or a pinhole collimator. After early technical problems with collimation and the production method of /sup 13/NH/sub 4//sup +/ were overcome, reproducible high quality myocardial images were consistently obtained. The normal myocardial image was established to be of a homogeneous ''doughnut'' configuration. Imaging studies performed in patients with varying manifestations of ischemic and valvular heart disease showed a high incidence of localized perfusion defects, especially in patients with acute myocardial infarction. Sequential studies at short intervals in patients with acute infarction showed correlation between alterations in regional perfusion and the clinical course of the patient. It is concluded that myocardial imaging with /sup 13/NH/sub 4//sup +/ and a scintillation camera provides a valid and noninvasive means of assessing regional myocardial perfusion. This method is especially suitable for sequential studies of acute cardiac patients at short intervals. Coincidence imaging of the 511 keV annihilation irradiation provides a tomographic and potentially quantitative assessment of the

  16. Use of neural networks to improve quality control of interpretations in myocardial perfusion imaging

    DEFF Research Database (Denmark)

    Tagil, K.; Marving, J.; Lomsky, M.

    2008-01-01

    BACKGROUND: The aim of this study was to explore the feasibility of using a technique based on artificial neural networks for quality assurance of image reporting. The networks were used to identify potentially suboptimal or erroneous interpretations of myocardial perfusion scintigrams (MPS......). METHODS: Reversible perfusion defects (ischaemia) in each of five myocardial regions, as interpreted by one experienced nuclear medicine physician during his daily routine of clinical reporting, were assessed by artificial neural networks in 316 consecutive patients undergoing stress/rest 99m......Tc-sestamibi myocardial perfusion scintigraphy. After a training process, the networks were used to select the 20 cases in each region that were more likely to have a false clinical interpretation. These cases, together with 20 control cases in which the networks detected no likelihood of false clinical interpretation...

  17. Determinants of myocardial conduction velocity: implications for arrhythmogenesis.

    Directory of Open Access Journals (Sweden)

    James Harmsworth King

    2013-06-01

    Full Text Available Slowed myocardial conduction velocity (θ is associated with an increased risk of re-entrant excitation, predisposing to cardiac arrhythmia. θ is determined by the ion channel and physical properties of cardiac myocytes and by their interconnections. Thus, θ is closely related to the maximum rate of action potential (AP depolarisation ((dV/dtmax, as determined by the fast Na+ current (INa; the axial resistance (ra to local circuit current flow between cells; their membrane capacitances (cm; and to the geometrical relationship between successive myocytes within cardiac tissue. These determinants are altered by a wide range of pathophysiological conditions. Firstly, INa is reduced by the impaired Na+ channel function that arises clinically during heart failure, ischaemia, tachycardia, and following treatment with class I antiarrhythmic drugs. Such reductions also arise as a consequence of mutations in SCN5A such as those occurring in Lenègre disease, Brugada syndrome, sick sinus syndrome, and atrial fibrillation (AF. Secondly, ra, may be increased due to gap junction decoupling following ischaemia, ventricular hypertrophy and heart failure, or as a result of mutations in CJA5 found in idiopathic AF and atrial standstill. Finally, either ra or cm could potentially be altered by fibrotic change through the resultant decoupling of myocyte-myocyte connections and coupling of myocytes with fibroblasts. Such changes are observed in myocardial infarction and cardiomyopathy or following mutations in MHC403 and SCN5A resulting in hypertrophic cardiomyopathy or Lenègre disease respectively. This review defines and quantifies the determinants of θ and summarises experimental evidence that links changes in these determinants with reduced myocardial θ and arrhythmogenesis. It thereby identifies the diverse pathophysiological conditions in which abnormal θ may contribute to arrhythmia.

  18. Inhalation gases or gaseous mediators as neuroprotectants for cerebral ischaemia.

    Science.gov (United States)

    Sutherland, Brad A; Harrison, Joanne C; Nair, Shiva M; Sammut, Ivan A

    2013-01-01

    Ischaemic stroke is one of the leading causes of morbidity and mortality worldwide. While recombinant tissue plasminogen activator can be administered to produce thrombolysis and restore blood flow to the ischaemic brain, therapeutic benefit is only achieved in a fraction of the subset of patients eligible for fibrinolytic intervention. Neuroprotective therapies attempting to restrict the extent of brain injury following cerebral ischaemia have not been successfully translated into the clinic despite overwhelming pre-clinical evidence of neuroprotection. Therefore, an adequate treatment for the majority of acute ischaemic stroke patients remains elusive. In the stroke literature, the use of therapeutic gases has received relatively little attention. Gases such as hyperbaric and normobaric oxygen, xenon, hydrogen, helium and argon all possess biological effects that have shown to be neuroprotective in pre-clinical models of ischaemic stroke. There are significant advantages to using gases including their relative abundance, low cost and feasibility for administration, all of which make them ideal candidates for a translational therapy for stroke. In addition, modulating cellular gaseous mediators including nitric oxide, carbon monoxide, and hydrogen sulphide may be an attractive option for ischaemic stroke therapy. Inhalation of these gaseous mediators can also produce neuroprotection, but this strategy remains to be confirmed as a viable therapy for ischaemic stroke. This review highlights the neuroprotective potential of therapeutic gas therapy and modulation of gaseous mediators for ischaemic stroke. The therapeutic advantages of gaseous therapy offer new promising directions in breaking the translational barrier for ischaemic stroke.

  19. Chemokine Involvement in Lung Injury Secondary to Ischaemia/Reperfusion.

    Science.gov (United States)

    Rancan, Lisa; Paredes, Sergio D; Huerta, Luis; Casanova, Javier; Guzmán, Jorge; Garutti, Ignacio; González-Aragoneses, Federico; Simón, Carlos; Vara, Elena

    2017-06-01

    During transplant surgeries, the lung experiences an ischaemia-reperfusion (I/R)-induced damage identified as a significant cause of morbidity and mortality. However, the mechanisms by which I/R induces leucocyte accumulation and subsequent tissue damage in lung surgeries remain unknown. Therefore, the present study aims to assess the role of monocyte chemotactic protein 1 (MCP-1) and macrophage inflammatory protein 2 (MIP-2) in leucocyte chemotaxis related to lung injury secondary to I/R. Six pigs were subjected to an orthotopic left caudal lobe lung transplantation with a subsequent 60-min graft reperfusion (Transplant group). In addition, six animals underwent to sham surgery (Sham Group). Plasma samples and lung biopsies were collected before the beginning of pneumonectomy, before starting the reperfusion, and 30 min and 60 min after the beginning of the reperfusion. Plasma levels of intercellular adhesion molecule 1 (ICAM-1) and lung expressions of MCP-1, MIP-2, myeloperoxidase (MPO), and lung oedema were measured. Lung I/R caused substantial damage observed as pulmonary oedema. The oedema was evident after the ischemic insult and increased after reperfusion. After reperfusion, increased levels of MPO were observed which suggests an activation and infiltration of neutrophils into the lung tissue. After 30 min of reperfusion, MCP-1, MIP-2, and ICAM-1 levels were significantly increased compared to prepneumonectomy levels (p reperfusion (p reperfusion-induced lung injury.

  20. Dobutamine stress thallium-201 single-photon emission tomography versus echocardiography for evaluation of the extent and location of coronary artery disease late after myocardial infarction

    International Nuclear Information System (INIS)

    Elhendy, A.; Bax, J.J.; Domburg, R.T. van; Cornel, J.H.; Roelandt, J.R.T.C.; Valkema, R.; Reijs, A.E.M.; Krenning, E.P.

    1999-01-01

    Dobutamine stress echocardiography and thallium-201 myocardial perfusion scintigraphy are clinically useful methods for the evaluation of coronary artery disease (CAD). However, the relative merits of these imaging modalities in the evaluation of the extent of CAD after myocardial infarction have not been well studied. The aim of this study was to compare the accuracy of dobutamine stress echocardiography and simultaneous 201 Tl single-photon emission tomography (SPET) imaging for the diagnosis and localization of CAD late after acute myocardial infarction. Dobutamine (up to 40 μg kg -1 min -1 )-atropine (up to 1 mg) stress echocardiography in conjunction with stress-reinjection 201 Tl SPET was performed for the evaluation of myocardial ischaemia in 90 patients with previous myocardial infarction who underwent coronary angiography. Significant CAD was predicted on bases of myocardial ischemia (new or worsening wall motion abnormalities on echocardiography and reversible perfusion defects on 201 Tl SPET). Significant CAD (≥ 50% luminal diameter stenosis) was detected in 73 (81%) patients. The sensitivity, specificity and accuracy of echocardiography in detecting remote ischaemia for the diagnosis of remote CAD (present in 53 patients) were, respectively, 79% (CI 70%-88%), 85% (CI 77%-93%) and 81% (CI 73%-90%), while the corresponding figures for 201 Tl SPET were 75% (CI 66%-85%), 78% (CI 69%-87%) and 76% (CI 67%-86%) respectively (P = NS vs echocardiography). The sensitivity, specificity and accuracy of echocardiography in detecting peri-infarction ischaemia for the diagnosis of infarct-related artery stenosis (present in 70 patients) were, rspectively, 77% (CI 68%-86%), 85% (CI 78%-92%) and 79% (CI 70%-87%) while the corresponding figures for 201 Tl SPET were 73% (CI 64%-82%), 85% (CI 78%-92%) and 76% (CI 67%-84%) respectively (P = NS vs echocardiography). The agreement between the two methods for the diagnosis of peri-infarction and remote ischaemia was 70

  1. Effect of eating on thallium myocardial imaging

    International Nuclear Information System (INIS)

    Wilson, R.A.; Sullivan, P.J.; Okada, R.D.; Boucher, C.A.; Morris, C.; Pohost, G.M.; Strauss, H.W.

    1986-01-01

    To determine if eating between initial and delayed thallium images alters the appearance of the delayed thallium scan, a prospective study was performed; 184 subjects sent for routine thallium imaging were randomized into two groups, those who ate a meal high in carbohydrates between initial and delayed thallium myocardial images (n = 106), and those who fasted (n = 78). The 201 Tl images were interpreted in blinded fashion for global myocardial and pulmonary clearance of 201 Tl myocardial defects. The eating group had a significantly lower incidence of transient myocardial defects compared to the noneating group (7 percent vs 18 percent, respectively; p less than 0.05). The time between initial and delayed images and the incidence of exercise-induced ischemic ST-segment depression or pathologic Q waves on the electrocardiogram were not significantly different between the two groups. These data suggest that eating a high-carbohydrate meal between initial and delayed 201 Tl images causes increased 201 Tl myocardial clearance rates and may alter 201 Tl myocardial redistribution over time

  2. Calcinosis is associated with digital ischaemia in systemic sclerosis—a longitudinal study

    Science.gov (United States)

    Pope, Janet; Robinson, David; Jones, Niall; Khalidi, Nader; Docherty, Peter; Kaminska, Elzbieta; Masetto, Ariel; Sutton, Evelyn; Mathieu, Jean-Pierre; Ligier, Sophie; Grodzicky, Tamara; LeClercq, Sharon; Thorne, Carter; Gyger, Geneviève; Smith, Douglas; Fortin, Paul R.; Larché, Maggie; Abu-Hakima, Maysan; Rodriguez-Reyna, Tatiana S.; Cabral-Castaneda, Antonio R.; Fritzler, Marvin J.; Wang, Mianbo; Hudson, Marie

    2016-01-01

    Objective. To determine if ischaemia is a causal factor in the development of calcinosis in SSc. Methods. Patients with SSc were assessed yearly. Physicians reported the presence of calcinosis, digital ischaemia (digital ulcers, digital necrosis/gangrene, loss of digital pulp on any digits and/or auto- or surgical digital amputation) and nailfold capillary dropout assessed using a dermatoscope. The number of digits with digital ischaemia was used as an assessment of the severity of digital ischaemia. SSc specific antibodies were detected with a line immunoassay. Multiple logistic regression and Cox proportional hazards models were generated to determine associations between calcinosis, digital ischaemia and capillary dropout. Results. One thousand three hundred and five patients were included in this study, of whom 300 (23.0%) had calcinosis at study entry. In a cross-sectional multivariate analysis, at baseline, calcinosis was associated with digital ischaemia (odds ratio (OR) = 2.37, 95% CI: 1.66, 3.39), severity of ischaemia (OR = 1.12, 95% CI: 1.06, 1.18), capillary dropout (OR = 1.41, 95% CI: 1.05, 1.89), ACAs (OR = 1.68, 95% CI: 1.17, 2.43) and anti-RNA polymerase III antibodies (OR = 1.77, 95% CI: 1.08, 2.89). Current use of calcium channel blockers was inversely associated with the presence of calcinosis (OR = 0.70, 95% CI: 0.52, 0.96). Of the 805 patients with no calcinosis at study entry and at least one follow-up visit, 215 (26.7%) developed calcinosis during follow-up. Significant baseline predictors of the development of calcinosis in follow-up were digital ischaemia (hazard ratio (HR) = 1.82, 95% CI: 1.30, 2.54), capillary dropout (HR = 1.46, 95% CI: 1.08, 1.99), dcSSc (HR = 1.57, 95% CI: 1.11, 2.21), ACA (HR = 2.18, 95% CI: 1.50, 3.17) and anti-RNA polymerase III antibodies (HR = 2.58, 95% CI: 1.65, 4.04). Conclusion. Ischaemia may play a role in the development of calcinosis in SSc. PMID:27593964

  3. Calcinosis is associated with digital ischaemia in systemic sclerosis-a longitudinal study.

    Science.gov (United States)

    Baron, Murray; Pope, Janet; Robinson, David; Jones, Niall; Khalidi, Nader; Docherty, Peter; Kaminska, Elzbieta; Masetto, Ariel; Sutton, Evelyn; Mathieu, Jean-Pierre; Ligier, Sophie; Grodzicky, Tamara; LeClercq, Sharon; Thorne, Carter; Gyger, Geneviève; Smith, Douglas; Fortin, Paul R; Larché, Maggie; Abu-Hakima, Maysan; Rodriguez-Reyna, Tatiana S; Cabral-Castaneda, Antonio R; Fritzler, Marvin J; Wang, Mianbo; Hudson, Marie

    2016-12-01

    To determine if ischaemia is a causal factor in the development of calcinosis in SSc. Patients with SSc were assessed yearly. Physicians reported the presence of calcinosis, digital ischaemia (digital ulcers, digital necrosis/gangrene, loss of digital pulp on any digits and/or auto- or surgical digital amputation) and nailfold capillary dropout assessed using a dermatoscope. The number of digits with digital ischaemia was used as an assessment of the severity of digital ischaemia. SSc specific antibodies were detected with a line immunoassay. Multiple logistic regression and Cox proportional hazards models were generated to determine associations between calcinosis, digital ischaemia and capillary dropout. One thousand three hundred and five patients were included in this study, of whom 300 (23.0%) had calcinosis at study entry. In a cross-sectional multivariate analysis, at baseline, calcinosis was associated with digital ischaemia (odds ratio (OR) = 2.37, 95% CI: 1.66, 3.39), severity of ischaemia (OR = 1.12, 95% CI: 1.06, 1.18), capillary dropout (OR = 1.41, 95% CI: 1.05, 1.89), ACAs (OR = 1.68, 95% CI: 1.17, 2.43) and anti-RNA polymerase III antibodies (OR = 1.77, 95% CI: 1.08, 2.89). Current use of calcium channel blockers was inversely associated with the presence of calcinosis (OR = 0.70, 95% CI: 0.52, 0.96). Of the 805 patients with no calcinosis at study entry and at least one follow-up visit, 215 (26.7%) developed calcinosis during follow-up. Significant baseline predictors of the development of calcinosis in follow-up were digital ischaemia (hazard ratio (HR) = 1.82, 95% CI: 1.30, 2.54), capillary dropout (HR = 1.46, 95% CI: 1.08, 1.99), dcSSc (HR = 1.57, 95% CI: 1.11, 2.21), ACA (HR = 2.18, 95% CI: 1.50, 3.17) and anti-RNA polymerase III antibodies (HR = 2.58, 95% CI: 1.65, 4.04). Ischaemia may play a role in the development of calcinosis in SSc. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Rheumatology

  4. Reversibility of cerebral ischaemia. Dynamic and xenon computed tomography study on ischaemic cerebrovascular disease

    International Nuclear Information System (INIS)

    Ujiie, H.; Oikawa, A.; Satoh, K.; Onda, H.; Kagawa, M.; Takakura, K.; Kakinoki, Y.; Ono, Y.; Kobayashi, N.

    1994-01-01

    Flow studies using dynamic CT and xenon (Xe) CT were carried out in 25 patients with ischaemic stroke in the territory of the middle cerebral artery to define the clinical characteristics of cerebral ischaemia at a chronic stage. The parameter of peak height/mean transit time (PH/MTT) obtained from dynamic CT can provide an accurate index for blood circulation in the cerebral vascular bed. Xe CT measurements revealed various kinds of ischaemia around the infarction even in the chronic stages. In mild ischaemia of more than 30 ml/100 g/min, reduction of cerebral blood flow (CBF) was well correlated to the PH/MTT. However, in severe ischaemia between 20 and 30 ml/100 g/ min, changes of CBF were no longer correlated with the pH/MTT. There were cases showing severe reduction of CBF but which showed sufficient blood circulation (moderate value of PH/MTT). Mild reductions of CBF in parallel with decreased blood supply were often found in the peri-infarct area of infarctions in the centrum semiovale. On the other hand, infarctions in the cortico-subcortical region showed severe ischaemia, in even where blood circulation was relatively well sustained

  5. An integrative review of health-related quality of life in patients with critical limb ischaemia.

    Science.gov (United States)

    Monaro, Susan; West, Sandra; Gullick, Janice

    2017-10-01

    To examine the domains and the domain-specific characteristics within a peripheral arterial disease health-related quality of life framework for their usefulness in defining critical limb ischaemia health-related quality of life. Critical Limb Ischaemia presents a highly individualised set of personal and health circumstances. Treatment options include conservative management, revascularisation or amputation. However, the links between treatment decisions and quality of life require further investigation. The framework for this integrative review was the peripheral arterial disease-specific health-related quality of life domains identified by Treat-Jacobson et al. The literature expanded and refined Treat-Jacobson's framework by modifying the characteristics to better describe health-related quality of life in critical limb ischaemia. Given that critical limb ischaemia is a highly individualised situation with powerful health-related quality of life implications, further research focusing on patient and family-centred decision-making relating to therapeutic options and advanced care planning is required. A critical limb ischaemia-specific, health-related quality of life tool is required to capture both the unique characteristics of this disorder, and the outcomes for active or conservative care among this complex group of patients. © 2016 John Wiley & Sons Ltd.

  6. Protective effects of Rosmarinic acid against renal ischaemia/reperfusion injury in rats

    International Nuclear Information System (INIS)

    Ozturk, H.; Ozturk, H.; Terzi, E.H.

    2014-01-01

    Objective: To investigate the potential protective effects of Rosmarinic acid (RA) on rats exposed to ischaemia/reperfusion renal injury. Methods: The prospective study was conducted at Abant Izzet Baysal University, Turkey, and comprised 21 male Spraque Dawley rats weighing 250-270g each. They were divided into three equal groups. Unilaterally nephrectomised rats were subjected to 60 minutes of left renal ischaemia followed by 60 minutes of reperfusion. Group 1 had shamoperated animals; group 2 had ischaemia/reperfusion untreated animals; and group 3 had ischaemia/reperfusion animals treated with rosmarinic acid. Serum creatinine, blood urea nitrogen, tissue malondialdehyde, glutathione peroxidase, superoxide dismutase and myeloperoxidase (MPO) activities, and light microscopic findings were evaluated. SPSS 17 was used for statistical analysis. Results: Treatment of rats with rosmarinic acid produced a reduction in the serum levels of creatinine and blood urea nitrogen compared to the other groups. However, no statistically significant difference was found. The levels of malondialdehyde and myeloperoxidase were decreased in the renal tissue of group 3, while glutathione peroxidose and superoxide dismutase levels remained unchanged. The injury score decreased in the treatment group rats compared to the untreated group. Rosmarinic acid significantly decreased focal glomerular necrosis, dilatation of Bowman's capsule, degeneration of tubular epithelium, necrosis in tubular epithelium, and tubular dilatation. Conclusions: Rosmarinic acid prevented ischaemia/reperfusion injury in the kidneys by decreasing oxidative stress. (author)

  7. Lower limb ischaemia and reperfusion injury in healthy volunteers measured by oxidative and inflammatory biomarkers.

    Science.gov (United States)

    Halladin, N L; Ekeløf, S; Alamili, M; Bendtzen, K; Lykkesfeldt, J; Rosenberg, J; Gögenur, I

    2015-01-01

    Ischaemia-reperfusion (IR) injury is partly caused by the release of reactive oxygen species and cytokines and may result in remote organ injury. Surgical patients are exposed to surgical stress and anaesthesia, both of which can influence the IR response. An IR model without these interfering factors of surgery is, therefore, useful to test the potential of antioxidant and cytokine-modulatory treatments. The aim of this study was to characterize a human ischaemia-reperfusion model with respect to oxidative and inflammatory biomarkers. Ten male volunteers were exposed to 20 minutes of lower limb ischaemia. Muscle biopsies and blood samples were taken at baseline and 5, 15, 30, 60 and 90 minutes after tourniquet release and analysed for malondialdehyde (MDA), ascorbic acid, dehydroascorbic acid, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-1 receptor antagonist (IL-1Ra), IL-6, IL-10, TNF-receptor (TNF-R)I, TNF-RII and YKL-40. We found no significant increase in MDA in the muscle biopsies after reperfusion. Plasma levels of oxidative and pro- and anti-inflammatory parameters showed no significant differences between baseline and after reperfusion at any sampling time. Twenty minutes of lower limb ischaemia does not result in an ischaemia-reperfusion injury in healthy volunteers, measurable by oxidative and pro- and anti-inflammatory biomarkers in muscle biopsies and in the systemic circulation. © The Author(s) 2014.

  8. Self-reported symptoms and risk factors for digital ischaemia among international world-class beach volleyball players

    NARCIS (Netherlands)

    van de Pol, Daan; Alaeikhanehshir, Sena; Maas, Mario; Kuijer, P. Paul F. M.

    2016-01-01

    The prevalence of ischaemia-related symptoms is remarkably high among elite indoor volleyball players. Since the exposure to sport-specific demands may be higher in beach volleyball compared to indoor volleyball, the aim of this study was to assess the prevalence of ischaemia-related symptoms and

  9. Lower limb ischaemia and reperfusion injury in healthy volunteers measured by oxidative and inflammatory biomarkers

    DEFF Research Database (Denmark)

    Halladin, N. L.; Busch, Sarah Victoria Ekeløf; Alamili, M.

    2015-01-01

    these interfering factors of surgery is, therefore, useful to test the potential of antioxidant and cytokine-modulatory treatments.The aim of this study was to characterize a human ischaemia-reperfusion model with respect to oxidative and inflammatory biomarkers. MATERIALS AND METHODS: Ten male volunteers were...... antagonist (IL-1Ra), IL-6, IL-10, TNF-receptor (TNF-R)I, TNF-RII and YKL-40. RESULTS: We found no significant increase in MDA in the muscle biopsies after reperfusion. Plasma levels of oxidative and pro- and anti-inflammatory parameters showed no significant differences between baseline and after reperfusion...... at any sampling time. CONCLUSION: Twenty minutes of lower limb ischaemia does not result in an ischaemia-reperfusion injury in healthy volunteers, measurable by oxidative and pro- and anti-inflammatory biomarkers in muscle biopsies and in the systemic circulation....

  10. Outcome of splanchnic blood flow determination in patients with suspected chronic intestinal ischaemia. A retrospective survey

    DEFF Research Database (Denmark)

    Møller, Søren; Madsen, Jan Lysgård

    2002-01-01

    BACKGROUND: Different diagnostic examinations have been applied in the management of patients with suspected intestinal ischaemia. In some centres, invasive determination of a meal-induced increase in splanchnic blood flow is used in the diagnostic process and in the selection of patients......: Seventy-three consecutive patients with suspected intestinal ischaemia were included during a 5-year period. Splanchnic blood flow was determined at baseline and after a standardized meal. The patients were classified into three groups according to the level of meal-induced increase in splanchnic blood...... a normal meal-induced response, 23 patients had a possible abnormal response and 10 patients had a definitive abnormal response, which gave evidence of chronic intestinal ischaemia. In the total patient population, the increase in splanchnic blood flow was significantly correlated to an increase in hepatic...

  11. Outcome of splanchnic blood flow determination in patients with suspected chronic intestinal ischaemia. A retrospective survey

    DEFF Research Database (Denmark)

    Møller, Søren; Madsen, Jan Lysgård

    2002-01-01

    a normal meal-induced response, 23 patients had a possible abnormal response and 10 patients had a definitive abnormal response, which gave evidence of chronic intestinal ischaemia. In the total patient population, the increase in splanchnic blood flow was significantly correlated to an increase in hepatic......BACKGROUND: Different diagnostic examinations have been applied in the management of patients with suspected intestinal ischaemia. In some centres, invasive determination of a meal-induced increase in splanchnic blood flow is used in the diagnostic process and in the selection of patients......: Seventy-three consecutive patients with suspected intestinal ischaemia were included during a 5-year period. Splanchnic blood flow was determined at baseline and after a standardized meal. The patients were classified into three groups according to the level of meal-induced increase in splanchnic blood...

  12. Prevention of Renal Injury After Induction of Ozone Tolerance in Rats Submitted to Warm Ischaemia

    Directory of Open Access Journals (Sweden)

    E. Barber

    1999-01-01

    Full Text Available On the basis that ozone (O3 can upregulate cellular antioxidant enzymes, a morphological, biochemical and functional renal study was performed in rats undergoing a prolonged treatment with O3 before renal ischaemia. Rats were divided into four groups: (1 control, a medial abdominal incision was performed to expose the kidneys; (2 ischaemia, in animals undergoing a bilateral renal ischaemia (30 min, with subsequent reperfusion (3 h; (3 O3 + ischaemia, as group 2, but with previous treatment with O3 (0.5 mg/kg per day given in 2.5 ml O2 via rectal administration for 15 treatments; (4 O2 + ischaemia, as group 3, but using oxygen (O2 alone. Biochemical parameters as fructosamine level, phospholipase A, and superoxide dismutases (SOD activities, as well as renal plasma flow (RPF and glomerular filtration rate (GFR, were measured by means of plasma clearance of p-amino-hippurate and inulin, respectively. In comparison with groups 1 and 3, the RPF and GFR were significantly decreased in groups 2 and 4. Interestingly, renal homogenates of the latter groups yielded significantly higher values of phospholipase A activity and fructosamine level in comparison with either the control (1 and the O3 (3 treated groups. Moreover renal SOD activity showed a significant increase in group 3 without significant differences among groups 1, 2 and 4. Morphological alterations of the kidney were present in 100%, 88% and 30% of the animals in groups 2, 4 and 3, respectively. It is proposed that the O3 protective effect can be ascribed to the substantial possibility of upregulating the antioxidant defence system capable of counteracting the damaging effect of ischaemia. These findings suggest that, whenever possible, ozone preconditioning may represent a prophylactic approach for minimizing renal damage before transplantation.

  13. Classification of myocardial infarction

    DEFF Research Database (Denmark)

    Saaby, Lotte; Poulsen, Tina Svenstrup; Hosbond, Susanne

    2013-01-01

    The classification of myocardial infarction into 5 types was introduced in 2007 as an important component of the universal definition. In contrast to the plaque rupture-related type 1 myocardial infarction, type 2 myocardial infarction is considered to be caused by an imbalance between demand...

  14. Effect of impaired fatty acid oxidation on myocardial kinetics of 11C- and 123I-labelled fatty acids

    International Nuclear Information System (INIS)

    Lerch, R.

    1986-01-01

    Positron emission tomography with palmitate 11 C and single photon imaging with terminally radioiodinated fatty acid analogues (FFA 123 I) were evaluated for the noninvasive assessment of regional myocardial fatty acid metabolism during ischaemia. Decreased uptake of tracer and delayed clearance of activity in the ischaemic myocardium were reported for both 11 C- and 123 I-labelled compounds. However, since during ischaemia both myocardial blood flow and oxidative metabolism are reduced concomitantly, either factor can be responsible for the changes observed. Experimental preparations in which fatty acid metabolism can be modified independently of flow are helpful for the characterization of the relationship between metabolism and myocardial kinetics of labelled fatty acids. Results obtained during flow-independent inhibition of fatty acid oxidation include the following observations: - In dogs with controlled coronary perfusion the rate of clearance of palmitate 11 C-activity is decreased during diminished delivery of oxygen, regardless of whether myocardial perfusion is concomitantly reduced or not. - In isolated rabbit hearts perfused at normal flow, the extraction of FFA 123 I is decreased during hypoxia. - During pharmacological inhibition of fatty acid oxidation the deiodination of FFA 123 I is markedly reduced in rat hearts in vivo and in vitro. (orig.)

  15. Noninvasive detection of coronary artery disease by myocardial imaging with thallium-201

    International Nuclear Information System (INIS)

    Narita, Michihiro; Kurihara, Tadashi; Usami, Masahisa

    1981-01-01

    Dipyridamole-loading myocardial imaging was performed in 38 patients with coronary artery diseases(CAD). The diagnostic accuracy of this method was 66%. The combination of dipyridamole-loading and exercise stress myocardial imaging increased the diagnostic sensitivity of CAD from 71% (exercise stress imaging only) to 87%. In addition, dipyridamole-loading myocardial imaging was useful for the diagnosis of CAD in patients who could not perform exercise stree test. Chest pain and ST-segment depression were induced less often during dipyridamole administration than exercise stress test. Animal experiments showed that dipyridamole caused abnormalities in myocardial blood flow and myocardial Tl uptake distal to the critical coronary stenosis. And dipyridamole increased myocardial blood flow by 142% and myocardial Tl concentration by 62% in the normally perfused myocardial segments. Ergonovine-loading myocardial imaging was performed in 8 patients with resting angina and without significant coronary stenosis. And in all of them, ergonivine induced cold-spots on myocardial imaging with or without chest pain and ST-segment shift. Ergonovine-loading myocardial imaging was useful for the diagnosis of angina induced by coronary artery spasm. The combination of initial and delayed resting myocardial imaging was useful to differentiate the underperfused but viable myocardium from the scar. And by comparing with radionuclide angiography obtained before and after nitroglycerin(NTG) administration, ATG-loading myocardial imaging and electrocardiogram(ECG) findings in 20 patients with CAD, we demonstrated that the transient defective myocadial segments were underperfused but viable. (author)

  16. Transient T wave Changes Concerning Arrhythmia

    Directory of Open Access Journals (Sweden)

    Hirofumi Tasaki, MD PhD

    2007-01-01

    Full Text Available T-wave changes are thought to be associated with the repolarization phase of myocardial action potential. Although it has been known that persistent T-wave change is associated with the heart disease or the prognosis, the sensitivity and the specificity are not necessarily satisfactory for clinical therapeutic strategy. Recent basic studies have shown that, in some kinds of pathological states, transient repolarization changes of myocardial action potential were associated with life-threatening arrhythmia. Also clinical studies are being conducted to elucidate the clinical implication of transient T-wave changes on electrocardiography (ECG in such an arrhythmia. Transient repolarization or T-wave change is thought to occur because of environmental or neurohumoral factors, circadian variation, stretching of myocardium or other triggers in daily life, resulting in fatal arrhythmia. Such fatal arrhythmias are thought to occur under restricted conditions even in the patients with serious heart disease. It is important to clarify and utilize the transient T-wave change directly associated with the fatal arrhythmia on a clinical basis. In this article, we first assess the mechanisms of transient repolarization or T-wave changes on ECG concerning fatal arrhythmia, and afterwards refer to possible attempts at clinical evaluation and application.

  17. Value of serum tenascin-C in patients with acute myocardial infarction

    African Journals Online (AJOL)

    Background: Myocardial infarction (MI) is defined as myocardial cell necrosis due to significant and sustained ischemia. TN-C is an extracellular matrix glycoprotein that is expressed in several important steps during the very early stage of cardiogenesis. TN-C is not normally expressed in the adult heart, but transiently ...

  18. Myocardial imaging. Coxsackie myocarditis

    Energy Technology Data Exchange (ETDEWEB)

    Wells, R.G.; Ruskin, J.A.; Sty, J.R.

    1986-09-01

    A 3-week-old male neonate with heart failure associated with Coxsackie virus infection was imaged with Tc-99m PYP and TI-201. The abnormal imaging pattern suggested myocardial infarction. Autopsy findings indicated that the cause was myocardial necrosis secondary to an acute inflammatory process. Causes of abnormal myocardial uptake of Tc-99m PYP in pediatrics include infarction, myocarditis, cardiomyopathy, bacterial endocarditis, and trauma. Myocardial imaging cannot provide a specific cause diagnosis. Causes of myocardial infarction in pediatrics are listed in Table 1.

  19. Myocardial imaging. Coxsackie myocarditis

    International Nuclear Information System (INIS)

    Wells, R.G.; Ruskin, J.A.; Sty, J.R.

    1986-01-01

    A 3-week-old male neonate with heart failure associated with Coxsackie virus infection was imaged with Tc-99m PYP and TI-201. The abnormal imaging pattern suggested myocardial infarction. Autopsy findings indicated that the cause was myocardial necrosis secondary to an acute inflammatory process. Causes of abnormal myocardial uptake of Tc-99m PYP in pediatrics include infarction, myocarditis, cardiomyopathy, bacterial endocarditis, and trauma. Myocardial imaging cannot provide a specific cause diagnosis. Causes of myocardial infarction in pediatrics are listed in Table 1

  20. Contemporary Management of ST-Elevation Myocardial Infarction.

    Science.gov (United States)

    Dind, Ashleigh; Allahwala, Usaid; Asrress, Kaleab N; Jolly, Sanjit S; Bhindi, Ravinay

    2017-02-01

    Recent advances have caused a major shift in the way ST-elevation myocardial infarctions are managed. This review explores the pharmacological and interventional techniques that have evidence for improving outcomes and the landmark trials that have sparked change. The new P2Y 12 inhibitors, ticagrelor and prasugrel, have been shown to be superior to clopidogrel in STEMI patients undergoing primary percutaneous coronary intervention. Concurrently, many technical aspects of percutaneous coronary intervention have been further clarified by trial data, with bare-metal stents, routine thrombus aspiration and femoral access showing evidence of inferiority. Ongoing trials will provide more information on the role of non-culprit lesion PCI, bioresorbable vascular scaffolds, mechanical devices in persistent ischaemia and early automatic implantable cardioverter-defibrillators for inducible ventricular tachycardia. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

  1. Atrial myxoma-related embolism resulting in acute limb ischaemia in ...

    African Journals Online (AJOL)

    This report presents an unusual case of limb ischaemia in the critical care setting, the cause of which was elucidated on echocardiography. Evaluation of the case highlights the importance of appropriate and timely investigation, in particular the role of bedside echocardiography. Although atrial myxomas are uncommon, ...

  2. Atrial myxoma-related embolism resulting in acute limb ischaemia in ...

    African Journals Online (AJOL)

    This report presents an unusual case of limb ischaemia in the critical care setting, the cause of which was elucidated on echocardio- ... while eating dinner. He had no complaints of preceding symptoms and had been well earlier that day. He remained unconscious and was transferred to a regional hospital where he was ...

  3. Digital ischaemia during cooling is independently related to nailfold capillaroscopic pattern in patients with Raynaud's phenomenon

    NARCIS (Netherlands)

    van Roon, Anniek M.; Smit, Andries J.; van Roon, Arie M.; Bootsma, Hendrika; Mulder, Douwe J.

    Objective. The aim of the study was to assess the association between plethysmographically measured vasospasms during stepwise cooling and recovery, as an index for digital ischaemia, and nailfold capillaroscopic pattern (NCP) severity in patients with primary or secondary RP, including SSc.

  4. Cisplatin induced acute mesenteric ischaemia: A case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Shivun Khosla

    Full Text Available Introduction: Cisplatin is a platinum-based chemotherapeutic agent, widely used in cancer therapies for numerous solid tumours. It is becoming more recognised that a potentially life-threatening complication of cisplatin is accelerated arterial and venous thrombosis. Presentation of case: We describe a case of a 62 year-old with no risk factors for vascular disease who presented with thromboembolic acute mesenteric ischaemia of the small bowel during treatment with cisplatin for head and neck cancer. Discussion: We review the literature on the incidence and pathogenesis of cisplatin induced arterial thrombosis and discuss current treatment options of acute mesenteric ischaemia detailing our management of this case. Conclusion: Cisplatin increases the risk of arterial thrombosis and this case report details acute mesenteric ischaemia secondary to its use. We hope to raise clinician awareness of this sequelae which can occur even in patients in the absence of other identifiable risk factors. Keywords: Cisplatin, Acute mesenteric ischaemia, Arterial thrombosis, Case report

  5. Effect of hypothermic renal ischaemia on renin secretion rate in man

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik Sahl; Petersen, H K; Giese, J

    1985-01-01

    Plasma renin concentration (PRC), renal blood flow (RBF) and renin secretion rate (RSR = renal veno-arterial PRC difference multiplied by renal plasma flow) were measured before and after a period of hypothermic renal ischaemia in seven patients undergoing surgery for renal calculi. After...

  6. Thrombin inhibition with melagatran does not attenuate renal ischaemia-reperfusion injury in rats

    DEFF Research Database (Denmark)

    Nitescu, Nicoletta; Grimberg, Elisabeth; Ricksten, Sven-Erik

    2007-01-01

    BACKGROUND: Renal ischaemia-reperfusion (IR) is associated with activation of the coagulation system and inflammation within the kidney. The aim of the present study was to examine the effects of selective thrombin inhibition with melagatran on kidney morphology and function in rats subjected...

  7. Intravenous digital subtraction angiography in patients with cerebral ischaemia

    International Nuclear Information System (INIS)

    Mantoni, M.; Neergaard, K.

    1989-01-01

    Over a two-year period, 167 patients with symptoms of transient ischaemic attacks or suspected minor stroke underwent intravenous digital subtraction angiography (DSA) of the carotid arteries. There were no major complications. Ninety-six patients had abnormal angiograms, 60 normal studies, and in 11 patients (7%) the examination was not of diagnostic quality, mostly because of motion artifacts. In 86 patients no therapeutic consequences resulted from the DSA examination. Twenty-six patients were referred for vascular surgery, and 34 patients had either anticoagulation or aspirin therapy. In 10 patients a primary medical cause was found for their cerebral vascular symptoms. It is concluded that intravenous DSA of the carotid arteries in patients with transient ischaemic attack is a safe, diagnostically useful procedure, that can also be used on an outpatient basis. (orig.)

  8. Integrated prediction of lesion-specific ischaemia from quantitative coronary CT angiography using machine learning: a multicentre study.

    Science.gov (United States)

    Dey, Damini; Gaur, Sara; Ovrehus, Kristian A; Slomka, Piotr J; Betancur, Julian; Goeller, Markus; Hell, Michaela M; Gransar, Heidi; Berman, Daniel S; Achenbach, Stephan; Botker, Hans Erik; Jensen, Jesper Moller; Lassen, Jens Flensted; Norgaard, Bjarne Linde

    2018-01-19

    We aimed to investigate if lesion-specific ischaemia by invasive fractional flow reserve (FFR) can be predicted by an integrated machine learning (ML) ischaemia risk score from quantitative plaque measures from coronary computed tomography angiography (CTA). In a multicentre trial of 254 patients, CTA and invasive coronary angiography were performed, with FFR in 484 vessels. CTA data sets were analysed by semi-automated software to quantify stenosis and non-calcified (NCP), low-density NCP (LD-NCP, difference (CDD, maximum difference in luminal attenuation per unit area) and plaque length. ML integration included automated feature selection and model building from quantitative CTA with a boosted ensemble algorithm, and tenfold stratified cross-validation. Eighty patients had ischaemia by FFR (FFR ≤ 0.80) in 100 vessels. Information gain for predicting ischaemia was highest for CDD (0.172), followed by LD-NCP (0.125), NCP (0.097), and total plaque volumes (0.092). ML exhibited higher area-under-the-curve (0.84) than individual CTA measures, including stenosis (0.76), LD-NCP volume (0.77), total plaque volume (0.74) and pre-test likelihood of coronary artery disease (CAD) (0.63); p quantitative plaque measures • Integrated ischaemia risk score showed higher prediction of ischaemia than standard approach • Contrast density difference had the highest information gain to identify lesion-specific ischaemia.

  9. Exercise induced ST elevation and residual myocardial ischemia in previous myocardial infarction

    International Nuclear Information System (INIS)

    Shimonagata, Tsuyoshi; Nishimura, Tsunehiko; Uehara, Toshiisa; Hayashida, Kohei; Saito, Muneyasu; Sumiyoshi, Tetsuya

    1987-01-01

    The purpose of this study was to evaluate the clinical significance of stress induced ST elevation on infarcted area in 65 patients with previous myocardial infarction (single vessel disease) who had stress thallium scan. Stress induced ST changes on infarcted area were compared with quantitative assessment of myocardial ischemia (thallium ischemic score; TIS) and extent of myocardial infarction (defect score; DS) derived from circumferential profile analysis. In patients with previous myocardial infarction in less than 3 month from the onset (n = 36), left ventricular ejection fraction (LVEF) and extent of abnormal LV wall motion were not significantly different between patients with stress induced ST elevation ( ≥ 2 mm, n = 26) and those with stress induced ST elevation ( < 2 mm, n = 10), while, in patients with previous myocardial infarction in more than 3 month (n = 29), patients with stress induced ST elevation ( ≥ 2 mm, n = 15) showed left ventricular dyskinesis more frequently than those with ST elevation ( < 2 mm, n = 14). In addition, the former showed significantly higher DS and significantly lower TIS than the latter. In patients with previous myocardial infarction in less than 3 month, patients with ST elevation ( ≥ 2 mm, n = 15) with prominent upright T wave (n = 15) had transient thallium defect in infarcted area in 73 % and they had significantly higher LVEF and TIS than those with ST elevation ( < 2 mm, n = 11). These results indicated that ST elevation in infarcted area reflect different significance according to the recovery of injured myocardium and stress induced ST elevation with prominent upright T wave in infarcted area reflect residual myocardial ischemia in less than 3 month from the onset of myocardial infarction. (author)

  10. Modulation of ASIC channels in rat cerebellar purkinje neurons by ischaemia-related signals

    Science.gov (United States)

    Allen, Nicola J; Attwell, David

    2002-01-01

    Acid-sensing ion channels (ASICs), activated by a decrease of extracellular pH, are found in neurons throughout the nervous system. They have an amino acid sequence similar to that of ion channels activated by membrane stretch, and have been implicated in touch sensation. Here we characterize the pH-dependent activation of ASICs in cerebellar Purkinje cells and investigate how they are modulated by factors released in ischaemia. Lowering the external pH from 7.4 activated an inward current at −66 mV, carried largely by Na+ ions, which was half-maximal for a step to pH 6.4 and was blocked by amiloride and gadolinium. The H+-gated current desensitized within a few seconds, but approximately 30% of cells showed a sustained inward current (11% of the peak current) in response to the maintained presence of pH 6 solution. The peak H+-evoked current was potentiated by membrane stretch (which occurs in ischaemia when [K+]o rises) and by arachidonic acid (which is released when [Ca2+]i rises in ischaemia). Arachidonic acid increased to 77% the fraction of cells showing a sustained current evoked by acid pH. The ASIC currents were also potentiated by lactate (which is released when metabolism becomes anaerobic in ischaemia) and by FMRFamide (which may mimic the action of related mammalian RFamide transmitters). These data reinforce suggestions of a mechanosensory aspect to ASIC channel function, and show that the activation of ASICs reflects the integration of multiple signals which are present during ischaemia. PMID:12205186

  11. Intestinal ischaemia during cardiac arrest and resuscitation: comparative analysis of extracellular metabolites by microdialysis.

    Science.gov (United States)

    Korth, Ulrike; Krieter, Heiner; Denz, Christof; Janke, Christoph; Ellinger, Klaus; Bertsch, Thomas; Henn, Claudia; Klein, Jochen

    2003-08-01

    Intestinal ischaemia is a major complication of shock syndromes causing translocation of bacteria and endotoxins and multiple organ failure in intensive care patients. The present study was designed to use microdialysis as a tool to monitor intestinal ischaemia after cardiac arrest and resuscitation in pigs. For this purpose, microdialysis probes were implanted in pig jejunal wall, peritoneum, skeletal muscle and brain, and interstitial fluid was obtained during circulatory arrest (induced by ventricular fibrillation) and after return of spontaneous circulation (ROSC). Cardiac arrest for 4 min caused a prolonged (60 min) reduction of blood flow in jejunal wall, muscle and brain as determined by the ethanol technique. This was accompanied by cellular damage in heart muscle and brain as indicated by increased levels of troponin-I and protein S-100, respectively. Plasma levels of glucose, lactate and choline were increased at 15-60 min following cardiac arrest. In contrast, cardiac arrest induced a rapid but variable decrease of interstitial glucose levels in all monitored organs; this decrease was followed by an increase over baseline during reperfusion. In the intestine, lactate, glutamate and choline levels were increased during ischaemia and reperfusion for 60-120 min; intestinal and peritoneal samples yielded parallel changes of lactate levels. Brain and muscle samples showed similar changes as in intestinum and peritoneum except for glutamate, which was increased in brain but not in muscle. We conclude that intestinal ischaemia occurs as a consequence of cardiac arrest and resuscitation and can be monitored by in vivo microdialysis. Comparative analysis by multi-site microdialysis reveals that the intestine is equally or even more sensitive to ischaemia than brain or muscle.

  12. Atrophy of the corpus callosum correlates with white matter lesions in patients with cerebral ischaemia

    International Nuclear Information System (INIS)

    Meguro, K.; Yamadori, A.; Constans, J.M.; Courtheoux, P.; Theron, J.; Viader, F.

    2000-01-01

    Many studies of white matter high signal (WMHS) on T2-weighted MRI have disclosed that it is related to cerebral ischaemia and to brain atrophy. Atrophy of the corpus callosum (CC) has also been studied in relation to ischaemia. Our objective was to test the hypothesis that CC atrophy could be due to ischaemia. We therefore assessed CC, WMHS and brain atrophy in patients with risk factors without strokes (the risk factor group) and in those with infarcts (the infarct group), to investigate the relationships between these factors. We studied 30 patients in the infarct group, 14 in the risk factor group, and 29 normal subjects. Using axial T1-weighted MRI, cortical atrophy and ventricular enlargement (brain atrophy) were visually rated. Using axial T2-weighted MRI, WMHS was assessed in three categories: periventricular symmetrical, periventricular asymmetrical and subcortical. Using the mid-sagittal T1-weighted image, the CC was measured in its anterior, posterior, midanterior and midposterior portions. In the normal group, no correlations were noted between parameters. In the infarct group, there were significant correlations between CC and brain atrophy, and between CC atrophy and WMHS. After removing the effects of age, gender and brain atrophy, significant correlations were noted between some CC measures and subcortical WMHS. In the risk factor group, there were significant correlations between CC and brain atrophy and between CC atrophy and WMHS. After allowance for age, gender and brain atrophy, significant correlations between some CC measures and periventricular WMHS remained. The hypothesis that CC atrophy could be due to cerebral ischaemia was supported by other analyses. Namely, for correlations between the extent of infarcts and partial CC atrophy in patients with anterior middle cerebral artery (MCA) and with posterior MCA infarcts, there were significant correlations between the extent of infarct and midanterior CC atrophy in the former, and posterior

  13. Atrophy of the corpus callosum correlates with white matter lesions in patients with cerebral ischaemia

    Energy Technology Data Exchange (ETDEWEB)

    Meguro, K.; Yamadori, A. [Section of Neuropsychology, Division of Disability Science, Tohoku University Graduate School of Medicine, 2-1, Seiryo-machi, Aoba-ku, 980-8575 Sendai (Japan); Constans, J.M.; Courtheoux, P.; Theron, J. [MR Unit, University of Caen School of Medicine, Caen (France); Viader, F. [Department of Neuroradiology, University of Caen School of Medicine, Caen (France)

    2000-06-01

    Many studies of white matter high signal (WMHS) on T2-weighted MRI have disclosed that it is related to cerebral ischaemia and to brain atrophy. Atrophy of the corpus callosum (CC) has also been studied in relation to ischaemia. Our objective was to test the hypothesis that CC atrophy could be due to ischaemia. We therefore assessed CC, WMHS and brain atrophy in patients with risk factors without strokes (the risk factor group) and in those with infarcts (the infarct group), to investigate the relationships between these factors. We studied 30 patients in the infarct group, 14 in the risk factor group, and 29 normal subjects. Using axial T1-weighted MRI, cortical atrophy and ventricular enlargement (brain atrophy) were visually rated. Using axial T2-weighted MRI, WMHS was assessed in three categories: periventricular symmetrical, periventricular asymmetrical and subcortical. Using the mid-sagittal T1-weighted image, the CC was measured in its anterior, posterior, midanterior and midposterior portions. In the normal group, no correlations were noted between parameters. In the infarct group, there were significant correlations between CC and brain atrophy, and between CC atrophy and WMHS. After removing the effects of age, gender and brain atrophy, significant correlations were noted between some CC measures and subcortical WMHS. In the risk factor group, there were significant correlations between CC and brain atrophy and between CC atrophy and WMHS. After allowance for age, gender and brain atrophy, significant correlations between some CC measures and periventricular WMHS remained. The hypothesis that CC atrophy could be due to cerebral ischaemia was supported by other analyses. Namely, for correlations between the extent of infarcts and partial CC atrophy in patients with anterior middle cerebral artery (MCA) and with posterior MCA infarcts, there were significant correlations between the extent of infarct and midanterior CC atrophy in the former, and posterior

  14. Dietary red palm oil supplementation reduces myocardial infarct size in an isolated perfused rat heart model

    Directory of Open Access Journals (Sweden)

    Esterhuyse Adriaan J

    2010-06-01

    Full Text Available Abstract Background and Aims Recent studies have shown that dietary red palm oil (RPO supplementation improves functional recovery following ischaemia/reperfusion in isolated hearts. The main aim of this study was to investigate the effects of dietary RPO supplementation on myocardial infarct size after ischaemia/reperfusion injury. The effects of dietary RPO supplementation on matrix metalloproteinase-2 (MMP2 activation and PKB/Akt phosphorylation were also investigated. Materials and methods Male Wistar rats were divided into three groups and fed a standard rat chow diet (SRC, a SRC supplemented with RPO, or a SRC supplemented with sunflower oil (SFO, for a five week period, respectively. After the feeding period, hearts were excised and perfused on a Langendorff perfusion apparatus. Hearts were subjected to thirty minutes of normothermic global ischaemia and two hours of reperfusion. Infarct size was determined by triphenyltetrazolium chloride staining. Coronary effluent was collected for the first ten minutes of reperfusion in order to measure MMP2 activity by gelatin zymography. Results Dietary RPO-supplementation decreased myocardial infarct size significantly when compared to the SRC-group and the SFO-supplemented group (9.1 ± 1.0% versus 30.2 ± 3.9% and 27.1 ± 2.4% respectively. Both dietary RPO- and SFO-supplementation were able to decrease MMP2 activity when compared to the SRC fed group. PKB/Akt phosphorylation (Thr 308 was found to be significantly higher in the dietary RPO supplemented group when compared to the SFO supplemented group at 10 minutes into reperfusion. There was, however, no significant changes observed in ERK phosphorylation. Conclusions Dietary RPO-supplementation was found to be more effective than SFO-supplementation in reducing myocardial infarct size after ischaemia/reperfusion injury. Both dietary RPO and SFO were able to reduce MMP2 activity, which suggests that MMP2 activity does not play a major role in

  15. The role of ADAMTS13 in acute myocardial infarction: cause or consequence?

    Science.gov (United States)

    Eerenberg, Elise S; Teunissen, Paul F A; van den Born, Bert-Jan; Meijers, Joost C M; Hollander, Maurits R; Jansen, Matthijs; Tijssen, Ruben; Beliën, Jeroen A M; van de Ven, Peter M; Aly, Mohamed F; Kamp, Otto; Niessen, Hans W; Kamphuisen, Pieter Willem; Levi, Marcel; van Royen, Niels

    2016-08-01

    ADAMTS13, a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13, is a metalloprotease that cleaves von Willebrand factor (VWF). There is considerable evidence that VWF levels increase and ADAMTS13 levels decrease in ST-elevation myocardial infarction (STEMI) patients. It is unclear whether this contributes to no reflow, infarct size, and intramyocardial haemorrhage (IMH). We aimed to determine the role of ADAMTS13 in STEMI patients and to investigate the benefits of recombinant ADAMTS13 (rADAMTS13) in a porcine model of myocardial ischaemia-reperfusion. In 49 consecutive percutaneous coronary intervention (PCI)-treated STEMI patients, blood samples were collected directly after through 7 days following PCI. Cardiac magnetic resonance was performed 4-6 days after PCI to determine infarct size and IMH. In 23 Yorkshire swine, the circumflex coronary artery was occluded for 75 min. rADAMTS13 or vehicle was administered intracoronary following reperfusion. Myocardial injury and infarct characteristics were assessed using cardiac enzymes, ECG, and histopathology. In patients with IMH, VWF activity and VWF antigen were significantly elevated directly after PCI and for all subsequent measurements, and ADAMTS13 activity significantly decreased at 4 and 7 days following PCI, in comparison with patients without IMH. VWF activity and ADAMTS13 activity were not related to infarct size. In rADAMTS13-treated animals, no differences in infarct size, IMH, or formation of microthrombi were witnessed compared with controls. No correlation was found between VWF/ADAMTS13 and infarct size in patients. However, patients suffering from IMH had significantly higher VWF activity and lower ADAMTS13 activity. Intracoronary administration of rADAMTS13 did not decrease infarct size or IMH in a porcine model of myocardial ischaemia-reperfusion. These data dispute the imbalance in ADAMTS13 and VWF as the cause of no reflow. © The Author 2016. Published by Oxford

  16. Right Bundle-Branch Block Associated with Transient Left Posterior ...

    African Journals Online (AJOL)

    The intraventricular conduction defect of left posterior hemiblock is very uncommon. Its occurrence as a transient phenomenon during the course of acute myocardial infarction, as described in this report, is exceptionally rare. The presentation revealed a planar reorientation of QRS forces, and demonstrated the masking ...

  17. Tomographic myocardial perfusion scintigraphy in children with Kawasaki disease

    International Nuclear Information System (INIS)

    Spielmann, R.P.; Nienaber, C.A.; Hausdorf, G.; Montz, R.

    1987-01-01

    Myocardial infarction and stenotic coronary lesions are serious late complications in children with Kawasaki disease. For the noninvasive assessment of myocardial perfusion, dipyridamole-redistribution 201 Tl emission computed tomography (ECT) was performed in seven children (age 2 8/12-8 7/12 yr) 3-20 mo after the acute stage of the disease. In all patients, coronary aneurysms had been demonstrated by cross-sectional echocardiography. The scintigrams of six children showed no significant regional reduction of myocardial thallium uptake. These children had remained asymptomatic since the acute stage of Kawasaki disease. Persistent and transient thallium defects were present in one child with documented myocardial infarction. For this patient, obstruction of corresponding coronary vessels was confirmed by contrast angiography. It is suggested, that 201 Tl ECT after dipyridamole-induced vasodilation may be used as a safe alternative to invasive coronary angiography for follow-up investigations in patients with Kawasaki disease

  18. Blockade of spinal nerves inhibits expression of neural growth factor in the myocardium at an early stage of acute myocardial infarction in rats.

    Science.gov (United States)

    Yue, W; Guo, Z

    2012-09-01

    Neural growth factor (NGF) is required for healing and sprouting of cardiac sympathetic and sensory nerves and plays important roles in cardiac protection, sustaining cardiac function and regeneration in ischaemic heart disease. The overexpression or lack of the NGF could be harmful to the heart. In this study, we examined the role of spinal nerves in the modulation of expression of the NGF in the myocardium at risk of ischaemia soon after acute myocardial infarction in rats. Coronary artery occlusion (CAO) was carried out in anaesthetized rats with and without preconditioning of blockade of the spinal nerves. The expression of the NGF protein and mRNA in the myocardium at risk of ischaemia was examined using immunohistochemical assay, enzyme-linked immunosorbent assay, and real-time quantitative reverse transcription polymerase chain reaction assay. In the left ventricle, immunoreactive cells and fibre-like structures were mainly located in the myocardium and in the epicardium. The NGF protein expression was increased by two-fold in the myocardium at risk of ischaemia during the 60 min of CAO, while the NGF mRNA was up-regulated three-fold, at 360 min after acute myocardial infarction. The blockade of the spinal nerves completely abolished the up-regulation of the NGF in the myocardium (Pmyocardial infarction, an effect which can be inhibited by the blockade of these nerves.

  19. Doxorubicin induced myocardial injury is exacerbated following ischaemic stress via opening of the mitochondrial permeability transition pore

    International Nuclear Information System (INIS)

    Gharanei, M.; Hussain, A.; Janneh, O.; Maddock, H.L.

    2013-01-01

    Chemotherapeutic agents such as doxorubicin are known to cause or exacerbate cardiovascular cell death when an underlying heart condition is present. However, the mechanism of doxorubicin-induced cardiotoxicity is unclear. Here we assess the cardiotoxic effects of doxorubicin in conditions of myocardial ischaemia reperfusion and the mechanistic basis of protection, in particular the role of the mitochondrial permeability transition pore (mPTP) in such protection. The effects of doxorubicin (1 μM) ± cyclosporine A (CsA, 0.2 μM; inhibits mPTP) were investigated in isolated male Sprague–Dawley rats using Langendorff heart and papillary muscle contraction models subjected to simulated ischaemia and reperfusion injury. Isolated rat cardiac myocytes were used in an oxidative stress model to study the effects of drug treatment on mPTP by confocal microscopy. Western blot analysis evaluated the effects of drug treatment on p-Akt and p-Erk 1/2 levels. Langendorff and the isometric contraction models showed a detrimental effect of doxorubicin throughout reperfusion/reoxygenation as well as increased p-Akt and p-Erk levels. Interestingly, CsA not only reversed the detrimental effects of doxorubicin, but also reduced p-Akt and p-Erk levels. In the sustained oxidative stress assay to study mPTP opening, doxorubicin decreased the time taken to depolarization and hypercontracture, but these effects were delayed in the presence of CsA. Collectively, our data suggest for the first that doxorubicin exacerbates myocardial injury in an ischaemia reperfusion model. If the inhibition of mPTP ameliorates the cardiotoxic effects of doxorubicin, then more selective inhibitors of mPTP should be further investigated for their utility in patients receiving doxorubicin. - Highlights: ► Doxorubicin exacerbates myocardial ischaemia reperfusion injury. ► Co-treatment with CsA protects against doxorubicin induced myocardial injury. ► CsA delays doxorubicin induced mPTP opening in laser

  20. Doxorubicin induced myocardial injury is exacerbated following ischaemic stress via opening of the mitochondrial permeability transition pore

    Energy Technology Data Exchange (ETDEWEB)

    Gharanei, M.; Hussain, A. [Department of Biomolecular and Sport Sciences, Coventry University, Cox Street, Coventry, CV1 5FB (United Kingdom); Janneh, O. [Department of Biomolecular and Sport Sciences, Coventry University, Cox Street, Coventry, CV1 5FB (United Kingdom); Pharmacology Research Laboratories, 70, Pembroke Place, The University of Liverpool, Liverpool. L69 3GF (United Kingdom); Maddock, H.L., E-mail: h.maddock@coventry.ac.uk [Department of Biomolecular and Sport Sciences, Coventry University, Cox Street, Coventry, CV1 5FB (United Kingdom)

    2013-04-15

    Chemotherapeutic agents such as doxorubicin are known to cause or exacerbate cardiovascular cell death when an underlying heart condition is present. However, the mechanism of doxorubicin-induced cardiotoxicity is unclear. Here we assess the cardiotoxic effects of doxorubicin in conditions of myocardial ischaemia reperfusion and the mechanistic basis of protection, in particular the role of the mitochondrial permeability transition pore (mPTP) in such protection. The effects of doxorubicin (1 μM) ± cyclosporine A (CsA, 0.2 μM; inhibits mPTP) were investigated in isolated male Sprague–Dawley rats using Langendorff heart and papillary muscle contraction models subjected to simulated ischaemia and reperfusion injury. Isolated rat cardiac myocytes were used in an oxidative stress model to study the effects of drug treatment on mPTP by confocal microscopy. Western blot analysis evaluated the effects of drug treatment on p-Akt and p-Erk 1/2 levels. Langendorff and the isometric contraction models showed a detrimental effect of doxorubicin throughout reperfusion/reoxygenation as well as increased p-Akt and p-Erk levels. Interestingly, CsA not only reversed the detrimental effects of doxorubicin, but also reduced p-Akt and p-Erk levels. In the sustained oxidative stress assay to study mPTP opening, doxorubicin decreased the time taken to depolarization and hypercontracture, but these effects were delayed in the presence of CsA. Collectively, our data suggest for the first that doxorubicin exacerbates myocardial injury in an ischaemia reperfusion model. If the inhibition of mPTP ameliorates the cardiotoxic effects of doxorubicin, then more selective inhibitors of mPTP should be further investigated for their utility in patients receiving doxorubicin. - Highlights: ► Doxorubicin exacerbates myocardial ischaemia reperfusion injury. ► Co-treatment with CsA protects against doxorubicin induced myocardial injury. ► CsA delays doxorubicin induced mPTP opening in laser

  1. Review Paper: Myocardial Rupture After Acute Myocardial Infarction ...

    African Journals Online (AJOL)

    Myocardial rupture complications after acute myocardial infarction are infrequent but lethal. They mainly involve rupture of the ventricular free wall, ventricular septum, papillary muscle, or combined. We compare features of different kinds of myocardial ruptures after acute myocardial infarction by reviewing the clinical ...

  2. The detection of intra-operative myocardial ischaemia. Preliminary experience with the right-sided precordial lead

    NARCIS (Netherlands)

    de Hert, S. G.; de Jongh, R. F.; van den Bossche, A. O.; de Maere, P. L.; Adriaensen, H. F.

    1989-01-01

    The value of monitoring the right precordial lead, V4R, to detect peri-operative ischaemic events during coronary artery surgery was studied in 60 patients. Thirty-four patients had only left-sided coronary disease (Group 1). The other 26 patients had both left-sided occlusive coronary artery

  3. Current interruption transients calculation

    CERN Document Server

    Peelo, David F

    2014-01-01

    Provides an original, detailed and practical description of current interruption transients, origins, and the circuits involved, and how they can be calculated Current Interruption Transients Calculationis a comprehensive resource for the understanding, calculation and analysis of the transient recovery voltages (TRVs) and related re-ignition or re-striking transients associated with fault current interruption and the switching of inductive and capacitive load currents in circuits. This book provides an original, detailed and practical description of current interruption transients, origins,

  4. Renal blood flow and metabolism after cold ischaemia: peroperative measurements in patients with calculi

    DEFF Research Database (Denmark)

    Petersen, H K; Henriksen, Jens Henrik Sahl

    1984-01-01

    and renal venous L/P ratio were almost constant, indicating no significant anaerobic processes being involved in the flow response. None of the patients showed any signs of reactive hyperaemia. It is concluded that hypothermic renal ischaemia may be followed by an increased renal vascular resistance even.......01) immediately after re-established perfusion and 36% (P less than 0.02) 30 min later. In one additional patient, who had a short warm ischaemia (8 min), the flow pattern was the same. As arterial pressure remained constant, the reduced RBF signifies an increased renal vascular resistance. Renal O2-uptake...... when signs of anaerobic metabolism are sparse or absent. This conception is in contrast to that gained from previous animal experiments where anaerobic processes are kept responsible for the changes. The mechanism behind the described response is unknown, but the changes are probably reversible....

  5. Ischaemia-induced (symptomatic) migraine attacks may be more frequent than migraine-induced ischaemic insults

    DEFF Research Database (Denmark)

    Olesen, Jes; Friberg, L; Olsen, T S

    1993-01-01

    with or without headache. A severe internal carotid stenosis/occlusion and reduced regional cerebral blood flow (rCBF) was demonstrated. Borderline ischaemia may thus prime the brain for developing migrainous aura with or without migraine (symptomatic migraine). Four patients had a combination of permanent...... deficits after the very first migraine attack, severe atherosclerosis, risk factors for stroke, high age and no family history of migraine. In these cases the evidence indicates that thromboembolic ischaemia had triggered an attack of migraine with aura (likely symptomatic migraine). Three young females...... presented long-lasting typical and severe idiopathic migraine with aura. Attack-associated rCBF reduction was likely to have caused permanent, mild, visual or somatosensory deficits (migrainous infarction). In five patients the relationship between migraine and stroke remained unresolved. It seems...

  6. Prognostic significance of distal blood pressure measurements in patients with severe ischaemia

    DEFF Research Database (Denmark)

    Paaske, William; Tønnesen, K H

    1980-01-01

    The clinical course was followed and the ankle and toe blood pressures were measured with the strain gauge technique on 5 occasions during 2 years in 43 patients with pain at rest and/or ischaemic ulceration due to severe ischaemia of the legs on the basis of occlusive arterial disease. Although...... arteriosclerosis of the legs in non-diabetic patients is generally considered a benign disease from the standpoint of limb survival, the critical level of TPI (systolic toe blood pressure/systolic arm blood pressure) was found to be 0.07 as a TPI below this value was associated with an overall 82% risk...... of amputation. With TPI above 0.07, the chance of successful conservative therapy was about 40%. Diabetics with severe ischaemia must be regarded as a high risk group in respect of amputation (64%) and lethality (64%). A variance analysis was made on the pressure data: In patients with low pressure peripheral...

  7. Recent concepts concerning cerebral ischaemia in man and their implications in therapeutic evaluations

    International Nuclear Information System (INIS)

    Depresseux, J.C.

    1987-01-01

    Recent concepts concerning focal cerebral ischaemia in man and resulting from the data obtained with positron emission tomography are reported. The evolutive steps in the ischaemic process are divided into: perfusion reserve; extraction reserve recruitment; ischaemic penumbra; lesional process and post-lesional developments. Circulatory and metabolic patterns corresponding to these evolutive steps are described and illustrated. The potentials of these data as guide-lines in therapeutic trial methodology are discussed [fr

  8. The effect of voluntarily ingested buprenorphine on rats subjected to surgically induced global cerebral ischaemia

    DEFF Research Database (Denmark)

    Kalliokoski, Otto Henrik; Abelson, Klas; Koch, Janne

    2010-01-01

    The effect of perioperatively administered buprenorphine analgesia on rats subjected to surgically induced global ischaemia was assessed. Rats supplied with buprenorphine, mixed in nut paste for voluntary ingestion, displayed significant reductions in postoperative excretions of faecal...... in buprenorphine-treated and untreated animals. A part from a slightly higher hyperthermia immediately after surgery and typical opiate-associated behaviour, the buprenorphine treatment had no apparent adverse effects on the experimental model. In contrast, the analgesic treatment improved the model by minimizing...

  9. Splenic infarction complicating percutaneous transluminal coeliac artery stenting for chronic mesenteric ischaemia: a case report.

    Science.gov (United States)

    Almeida, John A; Riordan, Stephen M

    2008-08-06

    Chronic mesenteric ischaemia is an important cause of abdominal pain, especially in older patients with risk factors for vascular disease. Until recently, surgical revascularization procedures such as endarterectomy and aorto-coeliac or aorto-mesenteric bypass grafting were the only available treatment options for patients with chronic mesenteric ischaemia. Percutaneous angioplasty and stenting have recently been shown to be effective and safe alternatives to surgical revascularization in high-risk patients with chronic mesenteric ischaemia. We report an 84-year-old woman with symptoms of chronic mesenteric ischaemia, including post-prandial abdominal pain and weight loss. Investigations demonstrated calcific stenoses at the origins of the celiac, superior mesenteric and inferior mesenteric arteries, along with nonocclusive calcification in the mid-splenic artery. Coeliac artery angioplasty and stenting was performed, resulting in excellent arterial dilatation at the stenotic point and distal filling of the coeliac and superior mesenteric arteries and their branches. Within hours of successful stenting of the coeliac artery, the patient developed severe left upper quadrant pain. Progress imaging demonstrated splenic infarction, likely as a result of calcific emboli dislodged from the calcified plaque at the origin of the celiac artery at the time of angioplasty and stenting. The left upper quadrant pain resolved after 8 days and the patient remains asymptomatic 2 years post-procedure. This is the first reported case of splenic infarction complicating otherwise successful coeliac artery stenting, presumably as a consequence of distal embolization of disrupted calcific plaque. This complication, occurring on a background of non-occlusive splenic arterial calcification, represents a novel cause of abdominal pain post-procedure.

  10. Splenic infarction complicating percutaneous transluminal coeliac artery stenting for chronic mesenteric ischaemia: a case report

    Directory of Open Access Journals (Sweden)

    Almeida John A

    2008-08-01

    Full Text Available Abstract Introduction Chronic mesenteric ischaemia is an important cause of abdominal pain, especially in older patients with risk factors for vascular disease. Until recently, surgical revascularization procedures such as endarterectomy and aorto-coeliac or aorto-mesenteric bypass grafting were the only available treatment options for patients with chronic mesenteric ischaemia. Percutaneous angioplasty and stenting have recently been shown to be effective and safe alternatives to surgical revascularization in high-risk patients with chronic mesenteric ischaemia. Case Presentation We report an 84-year-old woman with symptoms of chronic mesenteric ischaemia, including post-prandial abdominal pain and weight loss. Investigations demonstrated calcific stenoses at the origins of the celiac, superior mesenteric and inferior mesenteric arteries, along with nonocclusive calcification in the mid-splenic artery. Coeliac artery angioplasty and stenting was performed, resulting in excellent arterial dilatation at the stenotic point and distal filling of the coeliac and superior mesenteric arteries and their branches. Within hours of successful stenting of the coeliac artery, the patient developed severe left upper quadrant pain. Progress imaging demonstrated splenic infarction, likely as a result of calcific emboli dislodged from the calcified plaque at the origin of the celiac artery at the time of angioplasty and stenting. The left upper quadrant pain resolved after 8 days and the patient remains asymptomatic 2 years post-procedure. Conclusion This is the first reported case of splenic infarction complicating otherwise successful coeliac artery stenting, presumably as a consequence of distal embolization of disrupted calcific plaque. This complication, occurring on a background of non-occlusive splenic arterial calcification, represents a novel cause of abdominal pain post-procedure.

  11. Protective effects of dexrazoxane against acute ischaemia/reperfusion injury of rat hearts

    Czech Academy of Sciences Publication Activity Database

    Neckář, Jan; Boudíková, Adéla; Mandíková, Petra; Štěrba, M.; Popelová, O.; Mikšík, Ivan; Dabrowská, L.; Mráz, J.; Geršl, V.; Kolář, František

    2012-01-01

    Roč. 90, č. 9 (2012), s. 1303-1310 ISSN 0008-4212 R&D Projects: GA AV ČR(CZ) IAAX01110901; GA ČR(CZ) GA305/09/0416 Institutional research plan: CEZ:AV0Z50110509 Keywords : heart * dexrazoxane * ischaemia * reperfusion * infarct size * arrhythmias * cardioprotection * reactive oxygen species Subject RIV: FR - Pharmacology ; Medidal Chemistry Impact factor: 1.556, year: 2012

  12. Raynaud's phenomenon and digital ischaemia--pharmacologic approach and alternative treatment options.

    Science.gov (United States)

    Linnemann, Birgit; Erbe, Matthias

    2016-01-01

    The primary goal of therapy is to reduce the frequency and intensity of Raynaud's attacks and to minimize the related morbidity rather than to cure the underlying condition. Treatment strategies depend on whether Raynaud's phenomenon (RP) is primary or secondary. All patients should be instructed about general measures to maintain body warmth and to avoid triggers of RP attacks. Pharmacologic intervention can be useful for patients with severe and frequent RP episodes that impair the patient's quality of life. Calcium channel blockers are currently the most prescribed and studied medications for this purpose. There has been limited evidence for the efficacy of alpha-1-adrenergic receptor antagonists, angiotensin receptor blockers, topical nitrates or fluoxetine to treat RP. The intravenously administered prostacyclin analogue iloprost can reduce the frequency and severity of RP attacks and is considered a second-line therapy in patients with markedly impaired quality of life, critical digital ischaemia and skin ulcers who are at risk for substantial tissue loss and amputation. Phosphodiesterase inhibitors (e.g., sildenafil) can also improve RP symptoms and ulcer healing whereas endothelin-1 receptor antagonists (e.g., bosentan) are mainly considered treatment options in secondary prevention for patients with digital skin ulcers related to systemic sclerosis. However, their use in clinical practice has been limited by their high cost. Antiplatelet therapy with low-dose aspirin is recommended for all patients who suffer from secondary RP due to ischaemia caused by structural vessel damage. Anticoagulant therapy can be considered during the acute phase of digital ischaemia in patients with suspected vascular occlusive disease attributed to the occurrence of new thromboses. In patients with critical digital ischaemia, consideration should be given to hospitalisation, optimisation of medical treatment in accordance with the underlying disease and evaluation for a

  13. Angioplasty and stenting of the superior mesenteric artery in acute mesenteric ischaemia

    International Nuclear Information System (INIS)

    Lim, R.P; Dowling, R.J.; Thomson, K.R.

    2004-01-01

    Acute mesenteric ischaemia is a challenging diagnostic problem with a very high mortality. Traditionally, laparotomy is required for definitive management. We describe a successful case of angioplasty and stenting of the superior mesenteric artery in a surgically unfit patient. We recommend that stenting be considered only in situations where the diagnosis has been made prior to bowel infarction, and if the patient poses a poor operative risk. Copyright (2004) Blackwell Publishing Asia Pty Ltd

  14. Neuroprotective effect of progesterone on acute phase changes induced by partial global cerebral ischaemia in mice.

    Science.gov (United States)

    Aggarwal, Raman; Medhi, Bikash; Pathak, Ashis; Dhawan, Veena; Chakrabarti, Amitava

    2008-06-01

    The possible neuroprotective effect of progesterone, a steroid hormone, on acute phase changes in a mouse model of cerebral ischaemia induced by bilateral common carotid artery occlusion (BCAO) was studied. A total of 72 male mice were included in the study. The BCAO model was used to induce partial global cerebral ischaemia. Morphological assessment included measurement of infarct size and brain oedema. Post-ischaemic seizure susceptibility was assessed using a subconvulsive dose of pentylenetetrazole (30 mgkg(-1) i.p.). Biochemical estimations included tumour necrosis factor alpha (TNF-alpha) levels and enzyme parameters such as lipid peroxidation, superoxide dismutase, catalase and glutathione peroxidase, and protein estimation. BCAO induced a significant infarct size and oedema in the saline-treated control group, along with an increase in oxidative stress, indicated by increased lipid peroxidation and decreased levels of antioxidants such as superoxide dismutase, catalase and glutathione peroxidase. Progesterone (15 mgkg(-1) i.p.) administration showed a neuro-protective effect by significantly reducing the cerebral infarct size as compared with the control group. Post-ischaemic seizure susceptibility was also reduced as the number of positive responders decreased. Brain oedema subsided, but not significantly. Progesterone significantly reduced TNF-alpha levels compared with the ischaemia group. Progesterone improved levels of all the antioxidants, indicating activity against oxidative stress induced by BCAO. The results demonstrate the neuroprotective effect of progesterone against ischaemic insult, suggesting a role for the steroid as a neuroprotective agent.

  15. Changes in myocardial perfusion due to physical exercise in patients with stable coronary artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Kendziorra, Kai; Foerster, Marcus; Sabri, Osama; Kluge, Regine [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Walther, Claudia; Moebius-Winkler, Sven; Conradi, Katrin; Schuler, Gerhard; Hambrecht, Rainer [University of Leipzig, Heart Center, Leipzig (Germany)

    2005-07-01

    Percutaneous transluminal coronary angioplasty (PTCA) is one of the main therapy options for patients with coronary artery disease (CAD), resulting in an improvement in myocardial perfusion and exercise capacity. Nevertheless, studies have also demonstrated a positive effect of regular exercise training on myocardial perfusion and maximum exercise capacity. The aim of this study was to evaluate changes in myocardial stress perfusion after 1 year of exercise training in comparison with the effects of PTCA in patients with CAD. In 66 male patients with angiographically confirmed significant coronary artery stenosis in one target vessel, myocardial perfusion scintigraphy was performed at baseline and 12 months after randomisation into either a physical exercise group or a PTCA group. Circumferential count rate profiles in 16 wall segments were classified according to their relative count rate and localisation within or outside the area supplied by the stenosed vessel. Ischaemic segments showed a significant improvement in myocardial count rate within the target area after 12 months in both the PTCA and the training group (PTCA group: from 76.8{+-}4.9% to 86.6{+-}10.9%, p=0.03; training group: from 74.0{+-}7.3% to 83.7{+-}10.8%, p<0.01). Outside the target area only the training group showed a significant improvement (from 77.7{+-}4.4% to 91.7{+-}4.8%, p<0.01). Our data indicate a significant improvement in stress myocardial perfusion in the training group after 12 months. The ischaemia is reduced not only in the target region of the leading stenosis but also in other ischaemic myocardial areas. In contrast, after PTCA stress perfusion improves only in the initially ischaemic parts of the target area. (orig.)

  16. Assessment of myocardial perfusion using a new scanning agent

    Energy Technology Data Exchange (ETDEWEB)

    Khalil, M.N

    1987-01-01

    This work assessed a new compound: Tc-99m tertiary butyl isonitrile (T-BIN) in scanning the normal myocardium in dogs. Experimentally induced myocardial infarcts (M.I.) were detected. The compound cleared significantly from the blood within 15 minutes and from the lungs within an hour after intravenous administration. Liver uptake was high and remained so. Cardiac uptake occurred quickly and continued for 6 hours. Comparable results were obtained in normal humans and patients. Myocardial scanning was best after 60 minutes at rest or 30 minutes after exercise. Liver uptake sometimes obscured the detection of inferior M.I. but this problem was reduced using a 45/sup 0/ left anterior oblique view with a 20/sup 0/ cranial tilt. At rest 9/10 patients with M.I. showed defects corresponding to the infarct sites. In 20 patients with angina pectoris 16 had perfusion defects on exercise. In 15/16 patients reversible ischaemia was demonstrated. The reperfusion scans were best obtained at 4 hours post exercise. Both Tl-201 and T-BIN detected equally the infarcts (3/3) but in patients with angina 8/10 with T-BIN and 6/10 with Tl-201 showed defects. ECG gating of the T-BIN scans was also studied.

  17. A history of a prior myocardial infarct does not negate the utility of myocardial perfusion imaging in the evaluation of acute chest pain syndromes

    International Nuclear Information System (INIS)

    Zhou Danbing; Jonathan Knott; Leeanne Grigg; Meir Lichtenstein; Nathan Better

    2004-01-01

    Purpose: Acute myocardial perfusion imaging (MPI) for evaluation of patients with acute chest pain and a non-diagnostic electrocardiogram (ECG) has a high sensitivity and moderate specificity to detect acute ischaemia and predict cardiac events. However, previous studies excluded patients with a history of prior myocardial infarction (MI). The purpose of our study was to assess the utility of acute MPI for evaluating patients with acute chest pain and a non-diagnostic ECG. We aim to study patients both with and without a history of prior MI, including normal and abnormal studies, as well as to assess the independent predictive value of a prior MI history in determining patient outcome. Methods: We studied 367 consecutive patients with (group 1, n--107) and without. (group 2, n=260) a history of prior MI. 800 MBq Tc99m sestamibi was injected while chest pain was present ('HOT' MIBI). SPECT imaging was performed 1-6 hours post injection. Scan results were reported as,normal, ischaemia, infarct or equivocal. For patients with a defect, a 24-hour painfree study ( C OLD' MIBI) was offered to differentiate ischaemia from infarct. Follow-up was at 1 year by review of the patient's medical record. Outcomes were (1) Hard cardiac events (HE), defined as cardiac death and non-fatal MI, and (2) Total cardiac events (TE), defined as HE or revascularisation. Results: For the total study population, 206 had a normal study, with a HE rate 0.97% (2/206), while 161 had an abnormal study, with HE rate 12.4% (20/161). Patients in Group 2 were much more likely to have a normal study than those in Group 1 (p<.001). An equivocal result is seen in 5 patients, with no cardiac events, while 5 patients had a non-cardiac death. These groups were too small for separate analysis. A COLD MIBI was required in 77.6% of group 1, but only 24.2% of group 2 patients (p<0.001). On univariate analysis, acute ischaemia on MIBI scan, history of prior MI, diabetes, Q wave on ECG and age are all predictors

  18. Periodontitis and myocardial hypertrophy.

    Science.gov (United States)

    Suzuki, Jun-Ichi; Sato, Hiroki; Kaneko, Makoto; Yoshida, Asuka; Aoyama, Norio; Akimoto, Shouta; Wakayama, Kouji; Kumagai, Hidetoshi; Ikeda, Yuichi; Akazawa, Hiroshi; Izumi, Yuichi; Isobe, Mitsuaki; Komuro, Issei

    2017-04-01

    There is a deep relationship between cardiovascular disease and periodontitis. It has been reported that myocardial hypertrophy may be affected by periodontitis in clinical settings. Although these clinical observations had some study limitations, they strongly suggest a direct association between severity of periodontitis and left ventricular hypertrophy. However, the detailed mechanisms between myocardial hypertrophy and periodontitis have not yet been elucidated. Recently, we demonstrated that periodontal bacteria infection is closely related to myocardial hypertrophy. In murine transverse aortic constriction models, a periodontal pathogen, Aggregatibacter actinomycetemcomitans markedly enhanced cardiac hypertrophy with matrix metalloproteinase-2 activation, while another pathogen Porphyromonas gingivalis (P.g.) did not accelerate these pathological changes. In the isoproterenol-induced myocardial hypertrophy model, P.g. induced myocardial hypertrophy through Toll-like receptor-2 signaling. From our results and other reports, regulation of chronic inflammation induced by periodontitis may have a key role in the treatment of myocardial hypertrophy. In this article, we review the pathophysiological mechanism between myocardial hypertrophy and periodontitis.

  19. Experimental Study of Thallium 201 Redistribution in Transient Myocardial Ischemia

    Science.gov (United States)

    Tanaka, Toshiyuki; Mandal, Ashis K.; Wong, Dennis Q.

    1982-01-01

    The influence of differential washout on the redistribution phenomenon of thallium 201 chloride deposited in ischemic myocardium was investigated. Two groups of dogs had serial scintigraphic images and tissue counting performed. The first group had ischemia produced prior to the injection of the thallium and, following the control image after production of ischemia, the occlusion was released and serial images obtained over a three-hour period. The second group received thallium initially and after a control scintigraph was taken, ischemia was created and maintained for three hours via transthoracic ligature. Activity distribution was followed by serial images. Thallium content of ischemic areas was compared to the normal area by computer assisted data analysis. Tissues from the ischemic and normal areas from both groups were obtained after the serial images and counted. In the first group, prompt redistribution of activity into the ischemic areas was seen within 30 minutes of releasing the occlusion and was verified by tissue counting. Neither scintigraphic image changes nor tissue uptake differences were observed in the second group. The restoration of blood flow and consequently increased avidity for thallium probably accounted for the redistribution seen in the first group as there appeared to be no differential washout of activity in the second group from either the ischemic or normal areas to contribute to the redistribution phenomenon. ImagesFigure 1Figure 2 PMID:7120444

  20. Measuring myocardial perfusion

    DEFF Research Database (Denmark)

    Qayyum, A A; Kastrup, J

    2015-01-01

    Recently, focus has changed from anatomical assessment of coronary arteries towards functional testing to evaluate the effect of stenosis on the myocardium before intervention. Besides positron-emission tomography (PET), cardiac MRI (CMR), and cardiac CT are able to measure myocardial perfusion......-known and is used in routine clinical practice. However, PET uses radioactive tracers and has a lower spatial resolution compared to CMR and CT. CMR and CT are emerging techniques in the field of myocardial perfusion imaging. CMR uses magnetic resonance to obtain images, whereas CT uses x-rays during first....... Myocardial perfusion abnormalities are the first sign of the ischaemic cascade in the development of coronary artery disease (CAD). PET is considered the non-invasive clinical reference standard for absolute quantification of myocardial perfusion. The diagnostic and prognostic value of PET is well...

  1. Coronary collateral vessels in patients with previous myocardial infarction

    International Nuclear Information System (INIS)

    Nakatsuka, M.; Matsuda, Y.; Ozaki, M.

    1987-01-01

    To assess the degree of collateral vessels after myocardial infarction, coronary angiograms, left ventriculograms, and exercise thallium-201 myocardial scintigrams of 36 patients with previous myocardial infarction were reviewed. All 36 patients had total occlusion of infarct-related coronary artery and no more than 70% stenosis in other coronary arteries. In 19 of 36 patients with transient reduction of thallium-201 uptake in the infarcted area during exercise (Group A), good collaterals were observed in 10 patients, intermediate collaterals in 7 patients, and poor collaterals in 2 patients. In 17 of 36 patients without transient reduction of thallium-201 uptake in the infarcted area during exercise (Group B), good collaterals were seen in 2 patients, intermediate collaterals in 7 patients, and poor collaterals in 8 patients (p less than 0.025). Left ventricular contractions in the infarcted area were normal or hypokinetic in 10 patients and akinetic or dyskinetic in 9 patients in Group A. In Group B, 1 patient had hypokinetic contraction and 16 patients had akinetic or dyskinetic contraction (p less than 0.005). Thus, patients with transient reduction of thallium-201 uptake in the infarcted area during exercise had well developed collaterals and preserved left ventricular contraction, compared to those in patients without transient reduction of thallium-201 uptake in the infarcted area during exercise. These results suggest that the presence of viable myocardium in the infarcted area might be related to the degree of collateral vessels

  2. Efficacy and safety of ticagrelor versus aspirin in acute stroke or transient ischaemic attack of atherosclerotic origin: a subgroup analysis of SOCRATES, a randomised, double-blind, controlled trial.

    Science.gov (United States)

    Amarenco, Pierre; Albers, Gregory W; Denison, Hans; Easton, J Donald; Evans, Scott R; Held, Peter; Hill, Michael D; Jonasson, Jenny; Kasner, Scott E; Ladenvall, Per; Minematsu, Kazuo; Molina, Carlos A; Wang, Yongjun; Wong, K S Lawrence; Johnston, S Claiborne

    2017-04-01

    Ticagrelor is an effective antiplatelet therapy for patients with coronary atherosclerotic disease and might be more effective than aspirin in preventing recurrent stroke and cardiovascular events in patients with acute cerebral ischaemia of atherosclerotic origin. Our aim was to test for a treatment-by-ipsilateral atherosclerotic stenosis interaction in a subgroup analysis of patients in the Acute Stroke or Transient Ischaemic Attack Treated with Aspirin or Ticagrelor and Patient Outcomes (SOCRATES) trial. SOCRATES was a randomised, double-blind, controlled trial of ticagrelor versus aspirin in patients aged 40 years or older with a non-cardioembolic, non-severe acute ischaemic stroke, or high-risk transient ischaemic attack from 674 hospitals in 33 countries. We randomly allocated patients (1:1) to ticagrelor (180 mg loading dose on day 1 followed by 90 mg twice daily for days 2-90, given orally) or aspirin (300 mg on day 1 followed by 100 mg daily for days 2-90, given orally) within 24 h of symptom onset. Investigators classified all patients into atherosclerotic and non-atherosclerotic groups for the prespecified, exploratory analysis reported in this study. The primary endpoint was the time to occurrence of stroke, myocardial infarction, or death within 90 days. Efficacy analysis was by intention to treat. The SOCRATES trial is registered with ClinicalTrials.gov, number NCT01994720. Between Jan 7, 2014, and Oct 29, 2015, we randomly allocated 13 199 patients (6589 [50%] to ticagrelor and 6610 [50%] to aspirin). Potentially symptomatic ipsilateral atherosclerotic stenosis was reported in 3081 (23%) of 13 199 patients. We found a treatment-by-atherosclerotic stenosis interaction (p=0·017). 103 (6·7%) of 1542 patients with ipsilateral stenosis in the ticagrelor group and 147 (9·6%) of 1539 patients with ipsilateral stenosis in the aspirin group had an occurrence of stroke, myocardial infarction, or death within 90 days (hazard ratio 0·68 [95% CI 0·53-0

  3. PSH Transient Simulation Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Muljadi, Eduard [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-12-21

    PSH Transient Simulation Modeling presentation from the WPTO FY14 - FY16 Peer Review. Transient effects are an important consideration when designing a PSH system, yet numerical techniques for hydraulic transient analysis still need improvements for adjustable-speed (AS) reversible pump-turbine applications.

  4. Beneficial effects of intra-arterial and intravenous prostaglandin E1 in intestinal ischaemia-reperfusion injury.

    Science.gov (United States)

    San Norberto García, Enrique María; Taylor, James Henry; Cenizo, Noelia; Vaquero, Carlos

    2014-04-01

    Ischaemia-reperfusion (I/R) injury is encountered in conditions that diminish intestinal blood flow. There is no clinically feasible technique available for mucosal preservation. One hundred Wistar rats were subjected to intestinal ischaemia for 15 and 60 min (I15', I60'), followed by 1 and 7 days of reperfusion (R1d, R7d). Rats were subjected to ischaemia by clamping the superior mesenteric artery. Prostaglandin E1 (PGE1) (2.500 ng/kg intra-arterial bolus or 20 ng/kg intravenous infusion) was administered immediately prior to the commencement of the experimental period. Animals were divided into 20 groups: sham (laparotomy alone), sacrificed at 1 or 7 days; saline administration, 15 or 60 min of ischaemia, 1 or 7 days of reperfusion; prostaglandin E1 administration, 15 or 60 min of ischaemia, 1 or 7 days of reperfusion, each one for intra-arterial or intravenous administration. Ileal segments were excised and assessed for histopathological score, polymorphonuclear (PMN) leucocytes encountered and myeloperoxidase (MPO) activity measurement. I/R caused deterioration of histological characteristics. Prophylactic administration of PGE1 resulted in a significant decrease in the histological score compared with the respective saline group (analysis of variance, P prostaglandin E1 prevents I/R injury by diminishing histological damage parameters, inhibiting PMN leucocyte infiltration and attenuating MPO activity.

  5. A serial changes of thallium-201 myocardial images in a patient with nontransmural myocardial infarction

    International Nuclear Information System (INIS)

    Tanaka, Takeshi; Itoh, Yukiyoshi; Takayama, Yasuo

    1986-01-01

    A 66 year old man had suffered from inferior myocardial infarction one year ago and then suffered from effort angina. Recently rest angina attack frequently occurred and he was admitted because of angina attack refractory to TNG. The patient was diagnosed as broad nontransmural infarction. A serial thallium-201 myocardial imagings at rest and thallium-201 lung uptake imagings were performed and some interesting findings were obtained as followings. Myocardial imagings on 3rd day after admission showed no significant deffect, however EF was 34 %. Immediately after severe ischemic attack marked defect was noted at posterolateral region and ECG showed prominent precordial ST depression without accompanying significant ST change in II, III, aVF. On 3rd day after severe attack under hemodynamically and electrocardiographically stable state posterolateral defect improved, though still persisted. EF was 28 %. On 3rd day postop no marked defects were noted in myocardial imagings, so posterolateral defect at rest after severe ischemic attack was proved to be transient defect. In this case thallium-201 lung uptake was not noted before attack. Immediately after severe attack thallium lung uptake increased and maximal uptake was noted at basal zone of lung, however in chest X-P typical butterfly shadow was noted at upper zone of lung. On 3rd day after severe attack hemodynamics improved and butterfly shadow ceased, though thallium lung uptake increased and noted at upper zone of lung. After operation thallium lung uptake improved. (J.P.N.)

  6. I-123-labelled heptadecanoic acid as myocardial imaging agent: comparison with thallium-201 and first-pass nuclear ventriculography

    International Nuclear Information System (INIS)

    Abdullah, A.Z.; Hawkins, L.A.; Britton, K.E.; Elliott, A.T.; Stephens, J.D.

    1981-01-01

    Results of the use of 123 I-iodoheptadecanoic acid (HA) as a myocardial imaging agent in eight patients and six normals are presented. It was shown that 123 I-HA gave comparable results to the widely used radiopharmaceutical 201 Tl. However the advantages of using 123 I-HA are that the 159 KeV energy is better suited to the conventional gamma camera, it gives a lower radiation dose to the patient and has a lower cost per study. 123 I-HA also has an important advantage in its potential for studying regional myocardial metabolic activity; in one patient, a defect due to ischaemia was seen at rest with 123 I-HA but required stress to make it evident with 201 Tl imaging. (U.K.)

  7. Antipsychotic drugs and risks of myocardial infarction: a self-controlled case series study.

    Science.gov (United States)

    Brauer, Ruth; Smeeth, Liam; Anaya-Izquierdo, Karim; Timmis, Adam; Denaxas, Spiros C; Farrington, C Paddy; Whitaker, Heather; Hemingway, Harry; Douglas, Ian

    2015-04-21

    Antipsychotics increase the risk of stroke. Their effect on myocardial infarction remains uncertain because people prescribed and not prescribed antipsychotic drugs differ in their underlying vascular risk making between-person comparisons difficult to interpret. The aim of our study was to investigate this association using the self-controlled case series design that eliminates between-person confounding effects. All the patients with a first recorded myocardial infarction and prescription for an antipsychotic identified in the Clinical Practice Research Datalink linked to the Myocardial Ischaemia National Audit Project were selected for the self-controlled case series. The incidence ratio of myocardial infarction during risk periods following the initiation of antipsychotic use relative to unexposed periods was estimated within individuals. A classical case-control study was undertaken for comparative purposes comparing antipsychotic exposure among cases and matched controls. We identified 1546 exposed cases for the self-controlled case series and found evidence of an association during the first 30 days after the first prescription of an antipsychotic, for first-generation agents [incidence rate ratio (IRR) 2.82, 95% confidence interval (CI) 2.0-3.99] and second-generation agents (IRR: 2.5, 95% CI: 1.18-5.32). Similar results were found for the case-control study for new users of first- (OR: 3.19, 95% CI: 1.9-5.37) and second-generation agents (OR: 2.55, 95% CI: 0.93-7.01) within 30 days of their myocardial infarction. We found an increased risk of myocardial infarction in the period following the initiation of antipsychotics that was not attributable to differences between people prescribed and not prescribed antipsychotics. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Cardiology.

  8. von Willebrand factor deficiency leads to impaired blood flow recovery after ischaemia in mice.

    Science.gov (United States)

    de Vries, Margreet R; Peters, Erna A B; Quax, Paul H A; Nossent, A Yaël

    2017-06-28

    Neovascularisation, i. e. arteriogenesis and angiogenesis, is an inflammatory process. Therefore attraction and extravasation of leukocytes is essential for effective blood flow recovery after ischaemia. Previous studies have shown that von Willebrand factor (VWF) is a negative regulator of angiogenesis. However, it has also been shown that VWF facilitates leukocyte attraction and extravasation. We aimed to investigate the role of VWF in arteriogenesis and angiogenesis during post-ischaemic neovascularisation. Wild-type (WT) and VWF deficient (VWF -/- ) C57BL/6 mice were subjected to hindlimb ischaemia via double ligation of the left femoral artery, and blood flow recovery was followed over time, using Laser Doppler Perfusion Imaging. Blood flow recovery was impaired in VWF -/- mice. After 10 days, VWF -/- mice showed a 43 ± 5 % recovery versus 68 ± 5 % in WT. Immunohistochemistry revealed that both arteriogenesis in the adductor muscles and angiogenesis in the gastrocnemius muscles were reduced in VWF -/- mice. Furthermore, leukocyte infiltration in the affected adductor muscles was reduced in VWF -/- mice. Residual paw perfusion directly after artery ligation was also reduced in VWF -/- mice, indicating a decrease in pre-existing collateral arteriole density. When we quantified collateral arterioles, we observed a 31 % decrease in the average number of collateral arterioles in the pia mater compared to WT mice (57 ± 3 in WT vs 40 ± 4 pial collaterals in VWF -/- ). We conclude that VWF facilitates blood flow recovery in mice. VWF deficiency hampers both arteriogenesis and angiogenesis in a hindlimb ischaemia model. This is associated with impaired leukocytes recruitment and decreased pre-existing collateral density in the absence of VWF.

  9. Outcome of splanchnic blood flow determination in patients with suspected chronic intestinal ischaemia. A retrospective survey

    DEFF Research Database (Denmark)

    Møller, Søren; Madsen, Jan Lysgård

    2002-01-01

    flow: A, normal response (splanchnic blood flow > or = 200 ml/min); B, possible abnormal response (splanchnic blood flow 51-199 ml/min); and C, definitive abnormal response (splanchnic blood flow ... a normal meal-induced response, 23 patients had a possible abnormal response and 10 patients had a definitive abnormal response, which gave evidence of chronic intestinal ischaemia. In the total patient population, the increase in splanchnic blood flow was significantly correlated to an increase in hepatic...... oxygen uptake (r = 0.38, P abnormal meal-induced splanchnic blood flow and 30% of these patients...

  10. Mass spectrometry imaging of biomarker lipids for phagocytosis and signalling during focal cerebral ischaemia

    DEFF Research Database (Denmark)

    Nielsen, Mette M B; Lambertsen, Kate L; Clausen, Bettina H

    2016-01-01

    biomarker CD11b, and probably with cholesteryl ester. Mass spectrometry imaging can visualize spatiotemporal changes in the lipidome during the progression and resolution of focal cerebral inflammation and suggests that BMP(22:6/22:6) and N-acyl-phosphatidylethanolamines can be used as biomarkers......Focal cerebral ischaemia has an initial phase of inflammation and tissue injury followed by a later phase of resolution and repair. Mass spectrometry imaging (desorption electrospray ionization and matrix assisted laser desorption ionization) was applied on brain sections from mice 2 h, 24 h, 5d, 7...

  11. Gastric mucosal electrical potential difference, pH, blood flow, and morphology during hypoxia and selective gastric ischaemia with and without allopurinol pretreatment in anaesthetized dogs

    DEFF Research Database (Denmark)

    Højgaard, L; Bülow, J B; Madsen, J

    1990-01-01

    Ischaemia has been implicated in the pathogenesis of gastric mucosal disorders. The aim of this investigation was to study the gastric mucosal electrical potential difference (PD), pH, blood flow and morphology during hypoxia, gastric ischaemia, and gastric ischaemia following inhibition of free...... radical formation with allopurinol. PD and pH were measured simultaneously with an intragastric microelectrode, and the PD values were corrected for the liquid junction potentials created by the intragastric pH variation. Blood flow was measured by the radiolabelled microsphere technique in 18...... anaesthetized dogs. Short general hypoxia and short ischaemia caused reversible declines in PD, increases in pH, and no morphological damage. Ischaemia for 1 h caused a significant decline in PD persistent after reperfusion, an increase in pH, and morphological PD, but after reperfusion PD was normalized. Gross...

  12. Effects of diltiazem on myocardial perfusion abnormalities during exercise in patients with hypertrophic cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Sugihara, Hiroki; Taniguchi, Yoko; Ito, Kazuki [Kyoto Prefectural Univ. of Medicine (Japan)] [and others

    1998-12-01

    The effect of diltiazem on myocardial ischemia in patients with hypertrophic cardiomyopathy (HCM) was evaluated by exercise myocardial {sup 201}Tl single photon emission computed tomography (SPECT). Exercise myocardial SPECT was performed before and 8 weeks after oral administration of diltiazem (180 mg/day) in 20 patients with HCM who showed transient perfusion defects on exercise myocardial {sup 201}Tl SPECT under control conditions. SPECT images were divided into 17 segments. The {sup 201}Tl perfusion defects were visually scored and evaluated as the defect score. The transient dilation index was calculated as an index of subendocardial ischemia. Improvement of the defect score was demonstrated in 15 patients after the administration of diltiazem. The mean defect score decreased significantly from 9.90{+-}5.17 to 5.50{+-}4.89 (p<0.0001). Although 16 of 20 patients showed an abnormal transient dilation index before diltiazem treatment, 16 showed improvement and 13 of these normalized after diltiazem therapy. The mean transient dilation index decreased from 1.16{+-}0.10 to 1.02{+-}0.09 (p<0.0001). In conclusion, diltiazem prevents or diminishes myocardial ischemia in patients with HCM. (author)

  13. MRI of myocardial perfusion.

    Science.gov (United States)

    Jerosch-Herold, Michael; Muehling, Olaf; Wilke, Norbert

    2006-02-01

    An overwhelming number of myocardial perfusion studies are done by nuclear isotope imaging. Magnetic resonance imaging during the first pass of an injected, contrast bolus has some significant advantages for detection of blood flow deficits, namely higher spatial resolution, absence of ionizing radiation, and speed of the test. Previous clinical studies have demonstrated that excellent sensitivity and specificity can be achieved with MR myocardial perfusion imaging for detecting coronary artery disease, and assessment of patients with acute chest pain. Furthermore, an absolute quantification of myocardial blood flow is feasible, as was demonstrated by comparison of MR perfusion imaging, to measurements with isotope labeled microspheres in experimental models. An integrated assessment of perfusion, function, and viability, is thus feasible by MRI to answer important clinical challenges such as the identification of stunned or hibernating, but viable myocardium.

  14. Complete revascularisation versus treatment of the culprit lesion only in patients with ST-segment elevation myocardial infarction and multivessel disease (DANAMI-3—PRIMULTI)

    DEFF Research Database (Denmark)

    Engstrøm, Thomas; Kelbæk, Henning; Helqvist, Steffen

    2015-01-01

    BACKGROUND: Patients with acute ST-segment elevation myocardial infarction (STEMI) and multivessel coronary disease have a worse prognosis compared with individuals with single-vessel disease. We aimed to study the clinical outcome of patients with STEMI treated with fractional flow reserve (FFR...... electronically via a web-based system in permuted blocks of varying size by the clinician who did the primary PCI. All patients received best medical treatment. The primary endpoint was a composite of all-cause mortality, non-fatal reinfarction, and ischaemia-driven revascularization of lesions in non...

  15. Long term results of polytetrafluoroethylene in above knee femoropopliteal bypass for critical ischaemia.

    LENUS (Irish Health Repository)

    Kavanagh, E G

    2012-02-03

    Ninety-six consecutive above-knee femoropopliteal bypasses, using polytetrafluoroethylene (PTFE) preferentially, were performed for limb-threatening ischaemia. Cumulative primary graft patency was 68 per cent, 49 per cent and 36 per cent and limb salvage 93 per cent, 85 per cent and 75 per cent at 1, 3 and 5 yr respectively. As a result of poor long term survival (51 per cent at 5 yr), and the healing of remedial lesions before graft occlusion, 68 patients (72 per cent) required no further intervention. Eighteen secondary bypasses were undertaken, 12 using ipsilateral saphenous vein. In this group of elderly patients with poor life expectancy, where a limited operation is desirable, the use of PTFE provided excellent limb salvage with low morbidity. Although we can no longer justify our continued use of PTFE in every case of critical ischaemia because of its inferior patency to autogenous vein, we continue to use it preferentially in patients whose lifespan is likely to be short and in cases where a remedial lesion is present.

  16. Riboflavin (vitamin B-2) reduces hepatocellular injury following liver ischaemia and reperfusion in mice.

    Science.gov (United States)

    Sanches, Sheila Cristina; Ramalho, Leandra Naira Z; Mendes-Braz, Mariana; Terra, Vânia Aparecida; Cecchini, Rubens; Augusto, Marlei Josiele; Ramalho, Fernando Silva

    2014-05-01

    Riboflavin has been shown to exhibit anti-inflammatory and antioxidant properties in the settings of experimental sepsis and ischaemia/reperfusion (I/R) injury. We investigated the effect of riboflavin on normothermic liver I/R injury. Mice were submitted to 60 min of ischaemia plus saline or riboflavin treatment (30 μmoles/kg BW) followed by 6 h of reperfusion. Hepatocellular injury was evaluated by aminotransferase levels, reduced glutathione (GSH) content and the histological damage score. Hepatic neutrophil accumulation was assessed using the naphthol method and by measuring myeloperoxidase activity. Hepatic oxidative/nitrosative stress was estimated by immunohistochemistry. Liver endothelial and inducible nitric oxide synthase (eNOS/iNOS) and nitric oxide (NO) amounts were assessed by immunoblotting and a chemiluminescence assay. Riboflavin significantly reduced serum and histological parameters of hepatocellular damage, neutrophil infiltration and oxidative/nitrosative stress. Furthermore, riboflavin infusion partially recovered hepatic GSH reserves and decreased the liver contents of eNOS/iNOS and NO. These data indicate that riboflavin exerts antioxidant and anti-inflammatory effects in the ischaemic liver, protecting hepatocytes against I/R injury. The mechanism of these effects appears to be related to the intrinsic antioxidant potential of riboflavin/dihydroriboflavin and to reduced hepatic expression of eNOS/iNOS and reduced NO levels, culminating in attenuation of oxidative/nitrosative stress and the acute inflammatory response. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. The impact of exercise training on the diameter dilator response to forearm ischaemia in healthy men.

    Science.gov (United States)

    Thijssen, D H J; Tinken, T M; Hopkins, N; Dawson, E A; Cable, N T; Green, D J

    2011-04-01

    Recent studies found differences between groups in the rate of diameter increase following the flow-mediated dilation (FMD). Whilst exercise training alters the magnitude of the FMD, little is known about the impact of exercise training on the rate of diameter increase. The aim of this study is to examine post-cuff deflation changes in brachial artery diameter following 5 min forearm ischaemia every 2 weeks across 8-weeks of a handgrip exercise training regimen. Post-deflation changes in brachial artery diameter following 5-min of ischaemia were examined before, after and every 2-weeks across an 8-week handgrip training programme in healthy young men (n = 11) using echo-Doppler. The magnitude of dilation increased at week 2-4-6, but returned towards baseline values at week 8 (anova: P = 8.001). The time-to-peak diameter (42 ± 15s) demonstrated a significant prolongation at week 4 (77 ± 32s), but returned towards baseline values at weeks 6 and 8 (anova: P < 0.001). The rate of diameter increase did not differ across the intervention. Exercise training in healthy subjects is initially characterized by a larger dilation. Since the rate of dilation did not change, a longer time-to-peak dilation was necessary to achieve the increase in magnitude of dilation. As exercise training continues, the timing and magnitude of the peak diameter response returns to near baseline levels.

  18. [Effect of actovegin and solcoseryl on microcirculation in experimental critical lower limb ischaemia].

    Science.gov (United States)

    Orlova, A Iu; Sukovatykh, B S; Artiushkova, E B; Gordov, M Iu

    The authors examined the effect of actovegin and solcoseryl on microcirculation parameters in treatment of experimental critical lower limb ischaemia. The study included a total of 130 male Wistar albino rats divided into four groups: intact, control, first and second study groups. The intact group consisted of 10 animals used for assessment of the normal indices of microcirculation, with the remaining three groups comprising 40 rats each. All animals, except the intact ones, were subjected to modelled critical ischaemia of a hind limb. The control group animals received no treatment, with the rats of the first and second study groups given intraperitoneal actovegin and solcoseryl, respectively, at a dose of 50 μg/kg first injected 3 hours after the operation and then once daily for five days. The level of microcirculation in the murine crural muscles was assessed by means of laser Doppler flowmetry on postoperative days 5, 10, 21 and 28. At the same time intervals, we performed histological examination of the ischaemized muscles, determining the level of microcirculation, the level of arteriovenular shunting, the area of necrosis and capillary network density. It was determined that actovegin and solcoseryl exerted a positive effect on formation of new capillaries in the ischaemized muscles, increasing density of the capillary network, decreasing arteriovenular shunting, increasing the level of microcirculation, decreasing the specific area of muscular tissue necrosis. The obtained findings showed advantages of actovegin over solcoseryl by the dynamics of the parameters of microcirculation, arteriovenular shunting, and capillary network density.

  19. Stress induced right ventricular dysfunction: An indication of reversible right ventricular ischaemia

    International Nuclear Information System (INIS)

    Underwood, S.R.; Walton, S.; Emanuel, R.W.; Swanton, R.H.; Campos Costa, D.; Laming, P.J.; Ell, P.J.

    1987-01-01

    Stress induced changes in left ventricular ejection fraction are widely used in the detection and assessment of coronary artery disease. This study demonstrates that right ventricular dysfunction may also occur, and assesses its significance in terms of coronary artery anatomy. This study involved 14 normal subjects and 26 with coronary artery disease investigated by equilibrium radionuclide ventriculography, at rest and during maximal dynamic exercise. Mean normal resting right ventricular ejection fraction (RVEF) was 0.40 (SD 0.118), and all normal subjects increased RVEF with stress (mean ΔRVEF+0.13 SD 0.099). Mean ΔRVEF in the subjects with coronary artery disease was significantly lower at 0.00 (SD 0.080), but there was overlap between the two groups. The largest falls in RVEF were seen if the right coronary artery was occluded without retrograde filling. In this subgroup with the most severely compromised right ventricular perfusion (nine subjects), RVEF always fell with stress, and mean ΔRVEF was -0.08 (SD 0.050). There was no significant correlation between ΔLVEF and ΔRVEF, implying that the right ventricular dysfunction was due to right ventricular ischaemia, rather than secondary to left ventricular dysfunction. Stress induced right ventricular ischaemia can therefore be detected readily by radionuclide ventriculography. (orig.)

  20. Activated protein C attenuates acute ischaemia reperfusion injury in skeletal muscle.

    LENUS (Irish Health Repository)

    Dillon, J P

    2012-02-03

    Activated protein C (APC) is an endogenous anti-coagulant with anti-inflammatory properties. The purpose of the present study was to evaluate the effects of activated protein C in the setting of skeletal muscle ischaemia reperfusion injury (IRI). IRI was induced in rats by applying rubber bands above the levels of the greater trochanters bilaterally for a period of 2h followed by 12h reperfusion. Treatment groups received either equal volumes of normal saline or activated protein C prior to tourniquet release. Following 12h reperfusion, muscle function was assessed electrophysiologically by electrical field stimulation. The animals were then sacrificed and skeletal muscle harvested for evaluation. Activated protein C significantly attenuated skeletal muscle reperfusion injury as shown by reduced myeloperoxidase content, wet to dry ratio and electrical properties of skeletal muscle. Further in vitro work was carried out on neutrophils isolated from healthy volunteers to determine the direct effect of APC on neutrophil function. The effects of APC on TNF-alpha stimulated neutrophils were examined by measuring CD18 expression as well as reactive oxygen species generation. The in vitro work demonstrated a reduction in CD18 expression and reactive oxygen species generation. We conclude that activated protein C may have a protective role in the setting of skeletal muscle ischaemia reperfusion injury and that this is in part mediated by a direct inhibitory effect on neutrophil activation.

  1. Successful Treatment of Acute on Chronic Mesenteric Ischaemia by Common Iliac to Inferior Mesenteric Artery Bypass

    Directory of Open Access Journals (Sweden)

    D. N. Coakley

    2015-01-01

    Full Text Available Chronic mesenteric ischaemia is a rare and potentially fatal condition most commonly due to atherosclerotic stenosis or occlusion of two or more mesenteric arteries. Multivessel revascularisation of both primary mesenteric vessels, the celiac artery and superior mesenteric artery (SMA, is the current mainstay of treatment; however, in a certain cohort of patients, revascularisation one or both vessels may not be possible. Arteries may be technically unreconstructable or the patient may be surgically unfit for the prolonged aortic cross clamping times required. Here we present a case involving a 72-year-old woman with acute on chronic mesenteric ischaemia. She was a high risk surgical patient with severe unreconstructable stenotic disease of the SMA and celiac arteries. She was successfully treated with single vessel revascularisation of the inferior mesenteric artery (IMA via a common iliac to IMA reversed vein bypass. At two-year follow-up, the graft remains patent and the patient continues to be symptom-free and is maintaining her weight.

  2. LPS Pretreatment Attenuates Cerebral Ischaemia/Reperfusion Injury by Inhibiting Inflammation and Apoptosis.

    Science.gov (United States)

    Lv, Zhiquan; Liu, Chong; Zhai, Meili; Zhang, Qian; Li, Jun; Zheng, Fang; Peng, Mingqing

    2018-03-10

    Lipopolysaccharide (LPS) pretreatment has a strong neuroprotective effect on cerebral ischaemia/reperfusion injury (IRI), but the mechanism has not been fully elucidated to date. This study investigated the effect of LPS pretreatment on the pathway mediated by endoplasmic reticulum (ER) stress-CCAAT/enhancer-binding protein- homologous protein (CHOP) and the role of this pathway on cerebral ischaemia/reperfusion (I/R)-induced inflammation and apoptosis. Healthy male BALB/c mice were randomised into four groups as follows: sham operation group (sham group, n=30); LPS group (BALB/c mice treated with LPS, n=30); ischaemia/reperfusion group (I/R group, n=30) and I/R+LPS group (BALB/c mice treated with LPS before ischaemia, n=30). The mice were pre-treated with LPS (0.2 mg/kg) intra-peritoneally for three days prior to cerebral ischaemia. After 24 hours, the neurological deficit score, TTC staining and TUNEL assay were used to assess the neuroprotective effect of the LPS pretreatment against cerebral IRI. To assess whether the ER stress-CHOP pathway participated in the LPS-pretreatment neuroprotective mechanism, the expression levels of related proteins (GRP78, CHOP, caspase-12 and caspase-3) from the ischaemic cortical penumbra were detected via a western blot analysis. An immunohistochemical study was used to detect the expression and location of CHOP in the cortical penumbra. To further assess the protective effect of the LPS pretreatment, the concentrations of inflammatory factors (TNF-α, IL-6, IL-1β and IL-10) in the cortical penumbra were measured by ELISA, and ER stress-CHOP pathway inflammation-related caspase-11 was analysed through western blot analysis. As demonstrated by the experiments, the pretreatment with LPS significantly reduced the neurological deficit score and the infarct size of cerebral IRI. The expression levels of ER stress-CHOP pathway related proteins (GRP78, CHOP, caspase-12 and caspase-3) from the cortical penumbra were significantly

  3. Prognostic significance of stress myocardial ECG-gated perfusion imaging in asymptomatic patients with diabetic chronic kidney disease on initiation of haemodialysis

    Energy Technology Data Exchange (ETDEWEB)

    Momose, Mitsuru; Kondo, Chisato; Kobayashi, Hideki; Kusakabe, Kiyoko [Tokyo Women' s Medical University, School of Medicine, Department of Radiology, Shinjuku-ku, Tokyo (Japan); Babazono, Tetsuya [Tokyo Women' s Medical University, School of Medicine, Diabetes Centre, Shinjuku-ku, Tokyo (Japan); Nakajima, Takatomo [Tokyo Women' s Medical University, School of Medicine, Department of Cardiology, Shinjuku-ku, Tokyo (Japan)

    2009-08-15

    Diabetic patients with chronic kidney disease (CKD) frequently develop cardiac events within several years of the initiation of haemodialysis. The present study assesses the prognostic significance of stress myocardial ECG-gated perfusion imaging (MPI) in patients with diabetic CKD requiring haemodialysis. Fifty-five asymptomatic patients with diabetic stage V CKD and no history of heart disease scheduled to start haemodialysis were enrolled in this study (56{+-}11 years old; 49 with type 2 diabetes mellitus). All patients underwent {sup 201}Tl stress ECG-gated MPI 1 month before or after the initiation of haemodialysis to assess myocardial involvement. We evaluated SPECT images using 17-segment defect scores graded on a 5-point scale, summed stress score (SSS) and summed difference scores (SDS). The patients were followed up for at least 2 years (42{+-}15 months) to determine coronary intervention (CI) and heart failure (HF) as soft events and acute myocardial infarction (AMI) and all causes of deaths as hard events. The frequencies of myocardial ischaemia, resting perfusion defects, low ejection fraction and left ventricular (LV) dilatation were 24,20,29 and 49%, respectively. Ten events (18%) developed during the follow-up period including four CI, one HF, one AMI and four sudden deaths. Multivariate Cox analysis selected SDS (p=0.0011) and haemoglobin A{sub 1c} (HbA{sub 1c}) (p=0.0076) as independent prognostic indicators for all events. Myocardial ischaemia, in addition to glycaemic control, is a strong prognostic marker for asymptomatic patients with diabetic CKD who are scheduled to start haemodialysis. Stress MPI is highly recommended for the management and therapeutic stratification of such patients. (orig.)

  4. Coronary plaque quantification and fractional flow reserve by coronary computed tomography angiography identify ischaemia-causing lesions

    DEFF Research Database (Denmark)

    Gaur, Sara; Øvrehus, Kristian Altern; Dey, Damini

    2016-01-01

    tomography angiography (CTA)-derived fractional flow reserve (FFRCT), and lesion-specific ischaemia identified by FFR in a substudy of the NXT trial (Analysis of Coronary Blood Flow Using CT Angiography: Next Steps). METHODS AND RESULTS: Coronary CTA stenosis, plaque volumes, FFRCT, and FFR were assessed...

  5. Self-reported symptoms and risk factors for digital ischaemia among international world-class beach volleyball players.

    Science.gov (United States)

    Van De Pol, Daan; Alaeikhanehshir, Sena; Maas, Mario; Kuijer, P Paul F M

    2016-01-01

    The prevalence of ischaemia-related symptoms is remarkably high among elite indoor volleyball players. Since the exposure to sport-specific demands may be higher in beach volleyball compared to indoor volleyball, the aim of this study was to assess the prevalence of ischaemia-related symptoms and associated risk factors among world-class beach volleyball players. Therefore, a questionnaire survey was performed among beach volleyball players active during the 2013 Grand Slam Beach Volleyball in the Netherlands. In total, 60 of the 128 beach volleyball players (47%) participated: 26 males and 34 females from 17 countries. The self-reported prevalence of cold or blue or pale digits in the dominant hand during or immediately after practice or competition was 38% (n = 23). Two risk factors were independently associated with symptoms of blue or pale digits: more than 14 years playing volleyball (odds ratio (OR) 4.42, 90% confidence interval (90% CI) 1.30-15.07) and sex (female) (OR 4.62, 90% CI 1.15-18.57). In conclusion, the prevalence of symptoms associated with digital ischaemia is high among international world-class beach volleyball players. Female sex and the length of the volleyball career were independently associated with an increased risk of ischaemia-related symptoms. The high prevalence of these seemingly innocuous symptoms and possible associated risk factors warrant regular monitoring since early detection can potentially prevent thromboembolic complications and irreversible tissue damage.

  6. Systematic review of pharmacological therapies for the management of ischaemic pain in patients with non-reconstructable critical limb ischaemia.

    LENUS (Irish Health Repository)

    2017-08-23

    Critical limb ischaemia (CLI) is a severe manifestation of peripheral arterial disease, characterised by chronic ischaemic rest pain, ulcers or gangrene. Management of ischaemic pain is challenging in patients with no options for revascularisation and optimal pharmacological therapies have not been established.

  7. Effects of a heat shock protein inducer on the atrial fibrillation substrate caused by acute atrial ischaemia

    NARCIS (Netherlands)

    Sakabe, Masao; Shiroshita-Takeshita, Akiko; Maguy, Ange; Brundel, Bianca J. J. M.; Fujiki, Akira; Inoue, Hiroshi; Nattel, Stanley

    2008-01-01

    Aims Heat shock proteins (HSPs) are a set of endogenous cytoprotective factors activated by various pathological conditions. This study addressed the effects of geranylgeranylacetone (GGA), an orally active HSP inducer, on the atrial fibrillation (AF) substrate associated with acute atria( ischaemia

  8. Diagnostic Value of Blood D-dimer Level in Acute Mesenteric Ischaemia in the Rat: An Experimental Study

    Directory of Open Access Journals (Sweden)

    Hakan Kulacoglu

    2005-04-01

    Conclusion: These results do not adequately support the use of blood D-dimer level as an independent parameter in the diagnosis of mesenteric ischaemia due to arterial thrombosis. However, this parameter can be used together with other tests in eliminating the possibility of a thromboembolic event.

  9. Posturally induced microvascular constriction in patients with different stages of leg ischaemia: effect of local skin heating

    NARCIS (Netherlands)

    Ubbink, D. T.; Jacobs, M. J.; Tangelder, G. J.; Slaaf, D. W.; Reneman, R. S.

    1991-01-01

    1. Skin microcirculation was investigated in 12 asymptomatic subjects and 76 patients, grouped according to their ankle-to-brachial systolic blood pressure index, in order to evaluate to what extent posturally induced microvascular constriction is dependent on the stage of leg ischaemia at different

  10. Preserved cardiac mitochondrial function and reduced ischaemia/reperfusion injury afforded by chronic continuous hypoxia: Role of opioid receptors

    Czech Academy of Sciences Publication Activity Database

    Maslov, L. N.; Naryzhnaya, N. V.; Prokudina, E. S.; Kolář, František; Gorbunov, A. S.; Zhang, Y.; Wang, H.; Tsibulnikov, S.Yu.; Portnichenko, A. G.; Lasukova, T. V.; Lishmanov, Yu. B.

    2015-01-01

    Roč. 42, č. 5 (2015), s. 496-501 ISSN 1440-1681 R&D Projects: GA ČR(CZ) GAP303/12/1162 Institutional support: RVO:67985823 Keywords : cardioprotection * chronic hypoxia * ischaemia/reperfusion * mitochondrial function * opioid receptors Subject RIV: ED - Physiology Impact factor: 2.004, year: 2015

  11. Spectroscopic classification of transients

    DEFF Research Database (Denmark)

    Stritzinger, M. D.; Fraser, M.; Hummelmose, N. N.

    2017-01-01

    We report the spectroscopic classification of several transients based on observations taken with the Nordic Optical Telescope (NOT) equipped with ALFOSC, over the nights 23-25 August 2017.......We report the spectroscopic classification of several transients based on observations taken with the Nordic Optical Telescope (NOT) equipped with ALFOSC, over the nights 23-25 August 2017....

  12. Fluid dynamic transient analysis

    International Nuclear Information System (INIS)

    Vilhena Reigosa, R. de

    1992-01-01

    This paper describes the methodology adopted at NUCLEN for the fluid dynamic analyses for ANGRA 2. The fluid dynamic analysis allows, through computer codes to simulate and quantify the loads resulting from fluid dynamic transients caused by postulated ruptures or operational transients, in the piping of the safety systems and of the important operational systems. (author)

  13. World Health Organization definition of myocardial infarction: 2008-09 revision.

    Science.gov (United States)

    Mendis, Shanthi; Thygesen, Kristian; Kuulasmaa, Kari; Giampaoli, Simona; Mähönen, Markku; Ngu Blackett, Kathleen; Lisheng, Liu

    2011-02-01

    WHO has played a leading role in the formulation and promulgation of standard criteria for the diagnosis of coronary heart disease and myocardial infarction since early 1970s. The revised definition takes into consideration the following: well-resourced settings can use the ESC/ACC/AHA/WHF definition, which has new biomarkers as a compulsory feature; in resource-constrained settings, a typical biomarker pattern cannot be made a compulsory feature as the necessary assays may not be available; the definition must also have provision for diagnosing non-fatal events with incomplete information on cardiac biomarkers and the ECG; to facilitate epidemiologic monitoring definition must recognize fatal events with incomplete or no information on cardiac biomarkers and/or ECG and/or autopsy and/or coronary angiography. Category A definition is the same as ESC/ACC/AHA/WHF definition of MI, and can be applied to settings with no resource constraints. Category B definition of MI is to be applied whenever there is incomplete information on cardiac bio-markers together with symptoms of ischaemia and the development of unequivocal pathological Q waves. Category C definition (probable MI) is to be applied when individuals with MI may not satisfy Category A or B definitions because of delayed access to medical services and/or unavailability of electrocardiography and/or laboratory assay of cardiac biomarkers. In these situations, the term probable MI should be used when there is either ECG changes suggestive of MI or incomplete information on cardiac biomarkers in a person with symptoms of ischaemia with no evidence of a non-coronary reason. This article presents the 2008-09 revision of the World Health Organization (WHO) definition of myocardial infarction (MI) developed at a WHO expert consultation.

  14. Tourniquet-induced ischaemia-reperfusion injury: the comparison of antioxidative effects of small-dose propofol and ketamine

    Directory of Open Access Journals (Sweden)

    Karaca Omer

    Full Text Available Abstract Objectives: The aim of the present study was to investigate the preventive effects of propofol and ketamine as small dose sedation during spinal anaesthesia on tourniquet-induced ischaemia-reperfusion injury. Methods: 30 patients were randomly assigned into two groups of 15 patients. In the propofol group, sedation was performed with propofol 0.2 mg·kg-1 followed by infusion at a rate of 2 mg·kg-1·h-1. In the ketamine group, a continuous infusion of ketamine 0.5 mg·kg-1·h-1 was used until the end of surgery. Intravenous administration of midazolam was not used in any patients. Ramsay sedation scale was used for assessing the sedation level. Venous blood samples were obtained before propofol and ketamine infusion (T1, at 30 minutes (min of tourniquet ischaemia (T2, and 5 min after tourniquet deflation (T3 for malondialdehyde (MDA measurements. Results: No differences were noted between the groups in haemodynamic (p > 0.05 and demographic data (p > 0.05. There was no statistically significant difference between the two groups in terms of T1, T2 and T3 periods (p > 0.05. There was a statistically increase observed in MDA values respectively both in Group P and Group K between the reperfusion period (1.95 ± 0.59, 2.31 ± 0.48 and pre-ischaemia (1.41 ± 0.38, 1.54 ± 0.45, and ischaemia (1.76 ± 0.70, 1.71 ± 0.38 (µmoL-1 periods (p < 0.05. Conclusions: Small-dose propofol and ketamine has similar potential to reduce the oxidative stress caused by tourniquet-induced ischaemia-reperfusion injury in patients undergoing arthroscopic knee surgery under spinal anaesthesia.

  15. Exercise myocardial perfusion scintigraphy is useful for evaluating myocardial ischemia even in the elderly

    Energy Technology Data Exchange (ETDEWEB)

    Kurata, Chinori; Uehara, Akihiko; Sugi, Toshihiko; Yamazaki, Keisuke [Hamamatsu Univ. School of Medicine, Shizuoka (Japan); Tawarahara, Kei; Mikami, Tadashi; Matoh, Fumitaka; Odagiri, Keiichi

    2000-06-01

    Pharmacologic stress testing is recommended to elderly patients as a valuable alternative to exercise testing. We examined whether exercise testing is as useful for evaluating myocardial ischemia in the elderly as in the young. The consecutive 1,508 patients who underwent exercise {sup 201}Tl single-photon emission computed tomography (SPECT) were divided into six age groups: 6-29 years (n=56), 30-44 (n=143), 45-54 (n=311), 55-64 (n=498), 65-74 (n=402), and 75-88 (n=98). Both heart rate and rate-pressure product at peak exercise were significantly lower in patients aged 75-88 than in the other five groups. The frequency of ischemic ST depression was higher in patients aged 75-88 than in those aged 6-74, although the difference was not significant. Moreover, the frequency of {sup 201}Tl transient defect was significantly higher in patients aged 75-88 than in those aged 6-74. On the other hand, the sensitivity of ischemic ST depression for {sup 201}Tl transient defect was similar among the six groups, but the specificity was significantly lower in patients aged 75-88 than in those aged 6-74. In conclusion, exercise {sup 201}Tl SPECT is useful for evaluating myocardial ischemia even in the elderly, but exercise electrocardiography has limitations such as lower specificity in the elderly than {sup 201}Tl SPECT. (author)

  16. Exercise myocardial perfusion scintigraphy is useful for evaluating myocardial ischemia even in the elderly

    International Nuclear Information System (INIS)

    Kurata, Chinori; Uehara, Akihiko; Sugi, Toshihiko; Yamazaki, Keisuke; Tawarahara, Kei; Mikami, Tadashi; Matoh, Fumitaka; Odagiri, Keiichi

    2000-01-01

    Pharmacologic stress testing is recommended to elderly patients as a valuable alternative to exercise testing. We examined whether exercise testing is as useful for evaluating myocardial ischemia in the elderly as in the young. The consecutive 1,508 patients who underwent exercise 201 Tl single-photon emission computed tomography (SPECT) were divided into six age groups: 6-29 years (n=56), 30-44 (n=143), 45-54 (n=311), 55-64 (n=498), 65-74 (n=402), and 75-88 (n=98). Both heart rate and rate-pressure product at peak exercise were significantly lower in patients aged 75-88 than in the other five groups. The frequency of ischemic ST depression was higher in patients aged 75-88 than in those aged 6-74, although the difference was not significant. Moreover, the frequency of 201 Tl transient defect was significantly higher in patients aged 75-88 than in those aged 6-74. On the other hand, the sensitivity of ischemic ST depression for 201 Tl transient defect was similar among the six groups, but the specificity was significantly lower in patients aged 75-88 than in those aged 6-74. In conclusion, exercise 201 Tl SPECT is useful for evaluating myocardial ischemia even in the elderly, but exercise electrocardiography has limitations such as lower specificity in the elderly than 201 Tl SPECT. (author)

  17. Summary of transient management

    International Nuclear Information System (INIS)

    Sheron, B.W.

    1984-01-01

    This chapter reviews the papers on evaluating and managing transients, as given at the American Nuclear Society Topical Meeting on Anticipated and Abnormal Plant Transients in Light Water Reactors. Transient management involves both diverse and related areas such as analysis, systems performance, human performance, procedures, and training. State-of-the-art simulators are being improved to solve the constitutive equations for two-phase fluid flow by the development of a new generation of analysis codes which are simpler and faster than earlier codes. Both the US NRC and the nuclear industry are criticized for solving problems by adding additional requirements for the reactor operator rather than by recognizing design deficiencies

  18. Neurological deterioration after laminectomy for spondylotic cervical myeloradiculopathy: the putative role of spinal cord ischaemia.

    Science.gov (United States)

    Cybulski, G R; D'Angelo, C M

    1988-01-01

    Most cases of neurological deterioration after laminectomy for cervical radiculomyelopathy occur several weeks to months postoperatively, except when there has been direct trauma to the spinal cord or nerve roots during surgery. Four patients are described who developed episodes of neurological deterioration during the postoperative recovery period that could not be attributed to direct intraoperative trauma nor to epidural haematoma or instability of the cervical spine as a consequence of laminectomy. Following laminectomy for cervical radiculomyelopathy four patients were unchanged neurologically from their pre-operative examinations, but as they were raised into the upright position for the first time following surgery focal neurological deficits referrable to the spinal cord developed. Hypotension was present in all four cases during these episodes and three of the four patients had residual central cervical cord syndromes. These cases represent the first reported instances of spinal cord ischaemia occurring with post-operative hypotensive episodes after decompression for cervical spondylosis. PMID:3404170

  19. A Delayed Diagnosis of Chronic Mesenteric Ischaemia: The Role of Clinicians’ Cognitive Errors

    Directory of Open Access Journals (Sweden)

    Sern Wei Yeoh

    2016-04-01

    Full Text Available Chronic diarrhoeal illnesses with nausea and weight loss are a common indication for gastroenterology review. While many such cases have intra-luminal aetiologies, such as inflammatory bowel disease, coeliac disease or other malabsorptive conditions, with many other cases due to functional gut disorders or systemic malignancy, clinicians must also keep vascular disorders in mind. Here we report a patient with a delayed diagnosis of chronic mesenteric ischaemia after 6 months of gastrointestinal symptoms strongly mimicking an alternative diagnosis such as inflammatory bowel disease due an atypical predominance of nausea and diarrhoea rather than pain. We briefly review the literature on treatment of this condition but also discuss with particular attention the sequence of cognitive errors made by clinicians that led to a diagnostic delay, inviting readers to thus reflect on how such errors can be minimised in their practice.

  20. Animal Models of Focal Cerebral Ischaemia and Haemorrhagic Transformation: Considerations in Experimental Stroke Study Design.

    Science.gov (United States)

    Shearer, Jennifer A; Douglas, Andrew S; Kirby, Brian P; Tatlisumak, Turgut; Doyle, Karen M

    2017-09-05

    Ischaemic stroke is often complicated with haemorrhage within the infarct zone or in a remote location especially when treated with intravenous thrombolysis and/or thrombectomy. While these early recanalisation treatments are highly effective, some of the benefit is lost because of haemorrhagic complications and consequential neurological deterioration of the patients. A number of mechanisms have been described that mediate the haemorrhagic changes and several agents have been tested in experimental models for inhibiting post stroke haemorrhage. Here, we review and discuss the small animal models of focal cerebral ischaemia and post ischaemic stroke haemorrhagic transformation and how these models can best be utilised for developing further insights as well as potential treatment approaches for this serious clinical complication. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  1. Clinical value of serum lactate measurement in diagnosing acute mesenteric ischaemia.

    Science.gov (United States)

    Isfordink, C J; Dekker, D; Monkelbaan, J F

    2018-03-01

    Acute mesenteric ischaemia (AMI) is a life-threatening disease with a mortality rate around 60%. This high mortality rate is largely caused by diagnostic delay, which means there is a pressing need for a reliable biomarker. In clinical practice, serum lactate measurement is often used for the diagnosis of AMI. To assess the diagnostic value of serum lactate, we performed a literature search. Lactate has two different isomers. The well-known L-lactate, produced by anaerobic glycolysis, and the more unknown D-lactate which is only produced by intestinal bacteria. In this review, we present and evaluate the current literature on the diagnostic value of the measurement of both lactate isomers. Furthermore, we suggest another biomarker which might have the potential to serve as a useful diagnostic test in the future.

  2. Novel Use of Smartphone-based Infrared Imaging in the Detection of Acute Limb Ischaemia.

    Science.gov (United States)

    Peleki, A; da Silva, A

    2016-01-01

    Infrared thermal imaging is based on perfusion changes reflected by skin temperature variations. It is an established non-invasive diagnostic method within vascular surgery, with applications such as peripheral arterial disease assessment and prevention of diabetic foot complications. However, owing to hardware limitations or lack of resources, it is not yet widely used in clinical practice. A novel portable infrared imaging camera, easily powered via a smartphone and free App software, was used to obtain digital thermograms during the clinical evaluation of acute limb ischaemia (ALI). Portable infrared imaging represents a new promising tool for the assessment of tissue perfusion that can be applied at the bedside during clinical evaluation of suspected ALI.

  3. Sepsis and myocardial dysfunction

    Directory of Open Access Journals (Sweden)

    Rafaela Deczka Morsch

    2006-12-01

    Full Text Available Sepsis and septic shock are prevalent in the intensive care setting,accounting for more than 40% of mortality in this scenario. Theappropriate management and recognition of sepsis-inducedmyocardial dysfunction are paramount for its proper treatmentand probably impact mortality rates. The objective of this articleis to review its definition, pathophysiologic mechanisms, possibletreatments and current research on the subject according to acritical view.Cellular signaling involved in myocardial depression is not fullyunderstood. Disturbances in calcium homeostasis,cardiodepressant circulating factors, inflammatory mediators,nitric oxide and apoptosis act as synergistic pathways that leadto severely depressed cardiac function. The diagnosis ofmyocardial dysfunction during sepsis carries a worse prognosisand increased mortality.Myocardial dysfunction plays an important role in morbidity andmortality rate of critically ill patients. Current research in thisarea will continue to evolve; we will, therefore, soon have moreinsights into potential novel therapies that can change its mortalityrates.

  4. Sodium nitrate alleviates functional muscle ischaemia in patients with Becker muscular dystrophy.

    Science.gov (United States)

    Nelson, Michael D; Rosenberry, Ryan; Barresi, Rita; Tsimerinov, Evgeny I; Rader, Florian; Tang, Xiu; Mason, O'Neil; Schwartz, Avery; Stabler, Thomas; Shidban, Sarah; Mobaligh, Neigena; Hogan, Shomari; Elashoff, Robert; Allen, Jason D; Victor, Ronald G

    2015-12-01

    Becker muscular dystrophy (BMD) is a progressive X-linked muscle wasting disease for which there is no treatment. BMD is caused by in-frame mutations in the gene encoding dystrophin, a structural cytoskeletal protein that also targets other proteins to the sarcolemma. Among these is neuronal nitric oxide synthase mu (nNOSμ), which requires specific spectrin-like repeats (SR16/17) in dystrophin's rod domain and the adaptor protein α-syntrophin for sarcolemmal targeting. When healthy skeletal muscle is exercised, sarcolemmal nNOSμ-derived nitric oxide (NO) attenuates α-adrenergic vasoconstriction, thus optimizing perfusion. In the mdx mouse model of dystrophinopathy, this protective mechanism (functional sympatholysis) is defective, resulting in functional muscle ischaemia. Treatment with a NO-donating non-steroidal anti-inflammatory drug (NSAID) alleviates this ischaemia and improves the murine dystrophic phenotype. In the present study, we report that, in 13 men with BMD, sympatholysis is defective mainly in patients whose mutations disrupt sarcolemmal targeting of nNOSμ, with the vasoconstrictor response measured as a decrease in muscle oxygenation (near infrared spectroscopy) to reflex sympathetic activation. Then, in a single-arm, open-label trial in 11 BMD patients and a double-blind, placebo-controlled cross-over trial in six patients, we show that acute treatment with oral sodium nitrate, an inorganic NO donor without a NSIAD moiety, restores sympatholysis and improves post-exercise hyperaemia (Doppler ultrasound). By contrast, sodium nitrate improves neither sympatholysis, nor hyperaemia in healthy controls. Thus, a simple NO donor recapitulates the vasoregulatory actions of sarcolemmal nNOS in BMD patients, and constitutes a putative novel therapy for this disease. © 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.

  5. Effect of eating on thallium-201 myocardial redistribution after myocardial ischemia

    International Nuclear Information System (INIS)

    Angello, D.A.; Wilson, R.A.; Palac, R.T.

    1987-01-01

    To determine whether eating a high-carbohydrate meal between initial and delayed postexercise thallium-201 (Tl-201) imaging affects detection of Tl-201 redistribution during exercise stress testing, 16 patients with stable angina performed 2 Tl-201 treadmill exercise stress tests within a 14-day interval. Immediately after initial postexercise imaging, patients either drank a commercially available instant breakfast preparation for the intervention test or drank an equivalent volume of water for the control test. Comparable exercise workloads were achieved by exercising patients to the same heart rate for both tests. The order of the 2 (intervention and control) tests were randomized. All patients had at least 1 region of Tl-201 myocardial redistribution on either their eating or control test scans, although only 7 of the 16 had positive treadmill exercise test responses. Forty-six regions showing Tl-201 myocardial redistribution were identified in all 144 regions examined. Significantly more of these regions were identified on control test scans than on eating test scans: 11 of 46 on both test scans, 6 of 46 only on eating test scans and 29 of 46 only on control scans (p less than 0.001). Consistent with results of the quantitative regional analysis, the percentage of Tl-201 clearance over 4 hours in the 46 Tl-201 myocardial redistribution regions was 39 +/- 8% for the eating tests and 29 +/- 8% for control tests (mean +/- standard deviation, p less than 0.003). In 4 patients diagnosis of transient ischemia would have been missed because their 14 Tl-201 myocardial redistribution regions were detected only on the control test scans

  6. [Bonsai induced acute myocardial infarction].

    Science.gov (United States)

    Ayhan, Hüseyin; Aslan, Abdullah Nabi; Süygün, Hakan; Durmaz, Tahir

    2014-09-01

    Incidences of drug abuse and cannabis have increased in young adults, recently. Cannabis induced myocardial infarction has rarely been reported in these people. There is no any literature about a synthetic cannabinoid, being recently most popular Bonsai, to cause myocardial infarction. In this case report we presented a 33-year-old male patient who developed acute myocardial infarction after taking high doses of Bonsai.

  7. Transient Ischemic Attack

    Medline Plus

    Full Text Available ... Ischemic Attack TIA , or transient ischemic attack, is a "mini stroke" that occurs when a blood clot blocks an artery for a short time. The only difference between a stroke ...

  8. Transient Ischemic Attack

    Medline Plus

    Full Text Available ... TIA , or transient ischemic attack, is a "mini stroke" that occurs when a blood clot blocks an ... a short time. The only difference between a stroke and TIA is that with TIA the blockage ...

  9. Accessory atrioventricular myocardial connections in the developing human heart: relevance for perinatal supraventricular tachycardias

    NARCIS (Netherlands)

    Hahurij, Nathan D.; Gittenberger-de Groot, Adriana C.; Kolditz, Denise P.; Bökenkamp, Regina; Schalij, Martin J.; Poelmann, Robert E.; Blom, Nico A.

    2008-01-01

    BACKGROUND: Fetal and neonatal atrioventricular (AV) reentrant tachycardias can be life-threatening but resolve in most cases during the first year of life. The transient presence of accessory AV myocardial connections during annulus fibrosus development may explain this phenomenon. METHODS AND

  10. Biochemical markers of neonatal myocardial dysfunction.

    Science.gov (United States)

    Almeida, Cristina Maria; Carrapato, Manuel R G; Pinto, Fernando; Pinto, Mariana; Ferreira, Sofia; Schmitt, Denise; Marinho, Luis

    2011-04-01

    Cardiac ultrasounds (US) are not always available at the bedside. Cardiac Troponin I (cTnI), CK-MB and NT-proBNP may be an alternative or complementary to influence evaluation and treatment. To determine reference ranges of biochemical markers cTnI, CK-MB and NT-proBNP in normal neonates. Cord and blood samples were collected from neonates and the above biochemical markers were determined. Ultrasounds were performed blindly. CK-MB remains constant from cord blood to the first day, declining thereafter to almost half the values (81.5 vs 52.0 U/l); cTnI increases from 0.004 to 0.058 ng/ml by 72 h falling to 0.030 by day 10; NT-proBNP peaks by 24 h (5085.5 pg/ml), subsiding to 3388.5 pg/ml by day 3, falling to 1316.0 pg/ml by day 10. CK-MB, mostly of muscle origin and reflecting labor stress or injury, is not to recommend as a measure of myocardial damage in the neonate. The rise in cTnI may be explained by a degree of myocardial involvement, albeit physiological. The initial rise and subsequent fall of NT-proBNP represents the physiological ventricular overload of transient birth adaptation.

  11. Complications impaired endothelial progenitor cell function in Type 2 diabetic patients with or without critical leg ischaemia: implication for impaired neovascularization in diabetes.

    Science.gov (United States)

    Chen, M-C; Sheu, J-J; Wang, P-W; Chen, C-Y; Kuo, M-C; Hsieh, C-J; Chen, J-F; Chang, H-W

    2009-02-01

    This study tested the hypothesis that migratory function of endothelial progenitor cells (EPCs) is impaired in Type 2 diabetic patients with or without critical leg ischaemia. Seventy-four patients were classified into four groups: Type 2 diabetic (n = 21) and non-diabetic patients (n = 10) with critical leg ischaemia and Type 2 diabetic patients without lower extremity vascular disease (n = 30) and healthy subjects (n = 13). The number and functional activity of circulating and cultured EPCs were determined. The migratory function of cultured EPCs was significantly impaired in diabetic patients without (median, 48, interquartile range, 46, 49 count/view/well) and with (median, 51, interquartile range, 46, 60 count/view/well) critical leg ischaemia and non-diabetic patients with critical leg ischaemia (median, 49, interquartile range, 47, 55 count/view/well) compared with healthy subjects (median, 63, interquartile range, 57, 65 count/view/well) (P interquartile range, 1600, 6600/10(6) cytometric events) than Type 2 diabetic patients with critical leg ischaemia (median, 5300, interquartile range, 2400, 11,100/10(6) cytometric events), non-diabetic patients with critical leg ischaemia (median, 5550, interquartile range, 2000, 32,100/10(6) cytometric events) and healthy subjects (median, 5400, interquartile range, 2700, 8700/10(6) cytometric events) (P = 0.413). The migratory function of EPCs is impaired in patients with Type 2 diabetes, even in those without critical leg ischaemia. These findings present an important new insight into the pathogenesis of impaired neovascularization and critical limb ischaemia in diabetic patients and provide avenues of future clinical study.

  12. Effects of nicorandil on cardiac sympathetic nerve activity after reperfusion therapy in patients with first anterior acute myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Kasama, Shu; Toyama, Takuji; Suzuki, Tadashi; Kurabayashi, Masahiko [Gunma University School of Medicine, Department of Cardiovascular Medicine, Maebashi (Japan); Kumakura, Hisao; Takayama, Yoshiaki; Ichikawa, Shuichi [Cardiovascular Hospital of Central Japan, Gunma (Japan)

    2005-03-01

    Ischaemic preconditioning (PC) is a cardioprotective phenomenon in which short periods of myocardial ischaemia result in resistance to decreased contractile dysfunction during a subsequent period of sustained ischaemia. Nicorandil, an ATP-sensitive potassium channel opener, can induce PC effects on sympathetic nerves during myocardial ischaemia. However, its effects on cardiac sympathetic nerve activity (CSNA) and left ventricular remodelling have not been determined. In this study, we sought to determine whether nicorandil administration improves CSNA in patients with acute myocardial infarction (AMI). We studied 58 patients with first anterior AMI, who were randomly assigned to receive nicorandil (group A) or isosorbide dinitrate (group B) after primary coronary angioplasty. The nicorandil or isosorbide dinitrate was continuously infused for >48 h. The extent score (ES) was determined from {sup 99m}Tc-pyrophosphate scintigraphy, and the total defect score (TDS) was determined from {sup 201}Tl scintigraphy 3-5 days after primary angioplasty. The left ventricular end-diastolic volume (LVEDV) and left ventricular ejection fraction (LVEF) were determined by left ventriculography 2 weeks later. The delayed heart/mediastinum count (H/M) ratio, delayed TDS and washout rate (WR) were determined from {sup 123}I-meta-iodobenzylguanidine (MIBG) images 3 weeks later. The left ventriculography results were re-examined 6 months after treatment. Fifty patients originally enrolled in the trial completed the entire protocol. After treatment, no significant differences were observed in ES or left ventricular parameters between the two groups. However, in group A (n=25), the TDSs determined from {sup 201}Tl and {sup 123}I-MIBG were significantly lower (26{+-}6 vs 30{+-}5, P<0.01, and 32{+-}8 vs 40{+-}6, P<0.0001, respectively), the H/M ratio significantly higher (1.99{+-}0.16 vs 1.77{+-}0.30, P<0.005) and the WR significantly lower (36%{+-}8% vs 44%{+-}12%, P<0.005) than in group B

  13. Myocardial perfusion modeling using MRI

    DEFF Research Database (Denmark)

    Larsson, H B; Fritz-Hansen, T; Rostrup, Egill

    1996-01-01

    In the present study, it is shown that it is possible to quantify myocardial perfusion using magnetic resonance imaging in combination with gadolinium diethylenetriaminopentaacetic acid (Gd-DTPA). Previously, a simple model and method for measuring myocardial perfusion using an inversion recovery...

  14. Assessment of myocardial viability.

    Science.gov (United States)

    Travin, Mark I; Bergmann, Steven R

    2005-01-01

    The prevalence of left ventricular (LV) dysfunction and resultant congestive heart failure is increasing. Patients with this condition are at high risk for cardiac death and usually have significant limitations in their lifestyles. Although there have been advances in medical therapy resulting in improved survival and well being, the best and most definitive therapy, when appropriate, is revascularization. In the setting of coronary artery disease, accounting for approximately two thirds of cases of congestive heart failure, LV dysfunction often is not the result of irreversible scar but rather caused by impairment in function and energy use of still viable-myocytes, with the opportunity for improved function if coronary blood flow is restored. Patients with LV dysfunction who have viable myocardium are the patients at highest risk because of the potential for ischemia but at the same time benefit most from revascularization. It is important to identify viable myocardium in these patients, and radionuclide myocardial scintigraphy is an excellent tool for this. Single-photon emission computed tomography perfusion scintigraphy, whether using thallium-201, Tc-99m sestamibi, or Tc-99m tetrofosmin, in stress and/or rest protocols, has consistently been shown to be an effective modality for identifying myocardial viability and guiding appropriate management. Metabolic imaging with positron emission tomography radiotracers frequently adds additional information and is a powerful tool for predicting which patients will have an improved outcome from revascularization, including some patients referred instead for cardiac transplantation. Other noninvasive modalities, such as stress echocardiography, also facilitate the assessment of myocardial viability, but there are advantages and disadvantages compared with the nuclear techniques. Nuclear imaging appears to require fewer viable cells for detection, resulting in a higher sensitivity but a lower specificity than stress

  15. Flow motion waves with high and low frequency in severe ischaemia before and after percutaneous transluminal angioplasty

    OpenAIRE

    Hoffmann, Ulrich; Schneider, Ernst; Bollinger, Alfred

    2017-01-01

    Study of objective - The aim was to evaluate skin flux and prevalence of low and high frequency flow motion waves in patients with severe ischaemia due to peripheral arterial occlusive disease before and after percutaneous transluminal angioplasty (PTA) with and without local thrombolysis. Design - Flow motion was recorded by the laser Doppler technique at the dorsum of the foot before, one day, and one month after PTA. The results were separately analysed in patients with successful and unsu...

  16. CT and MRI findings of cirrhosis-related benign nodules with ischaemia or infarction after variceal bleeding

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Y.K., E-mail: jmyr@dreamwiz.co [Department of Diagnostic Radiology, Research Institute of Clinical Medicine, Chonbuk National University Hospital and Medical School, Jeon Ju (Korea, Republic of); Park, G.; Kim, C.S.; Han, Y.M. [Department of Diagnostic Radiology, Research Institute of Clinical Medicine, Chonbuk National University Hospital and Medical School, Jeon Ju (Korea, Republic of)

    2010-10-15

    Aim: To present computed tomography (CT) and magnetic resonance imaging (MRI) findings of cirrhosis-related benign nodules with ischaemia or infarction. Materials and methods: Sixteen consecutive patients (14 men and two women) who had been diagnosed with cirrhosis-related benign nodules with ischaemia or infarction after variceal bleeding based on the results of dynamic CT (n = 15) and MRI (n = 8) were included in this study. Five patients had histopathological confirmation via liver transplantation (n = 2) and percutaneous biopsy (n = 3). Images were analyzed for the enhancement pattern, signal intensities, location, and configuration of the lesions. Results: Most of the lesions were depicted as multifocal discrete or clustered nodules with some irregular patchy areas (size range 3-28 mm). They were predominantly found in subcapsular area or caudate lobe. Most nodular lesions were seen as hypoattenuating (hypointense) nodules with rim enhancement during dynamic CT or MRI. On T2-weighted images, nodular lesions were predominantly seen as target appearing hyperintense nodules. On follow-up images (range 2-24 months), most of the lesions disappeared or decreased in size. Conclusion: CT and MRI can be used to demonstrate characteristic findings of cirrhosis-related benign nodules with ischaemia or infarction. Rapid resolution of the nodules at follow-up imaging can also be helpful for diagnosing these lesions.

  17. Sensitivity of different types of fibres in rabbit skeletal muscle to pneumatic compression by tourniquet and to ischaemia.

    Science.gov (United States)

    Fridén, J; Pedowitz, R A; Thornell, L E

    1994-06-01

    Morphometric properties (distribution of types of fibre and fibre areas) in the non-necrotic regions of four different rabbit muscles (superficial portions of semimembranosus, biceps femoris, tibialis anterior, and soleus muscles) were measured 48 hours after a tourniquet had been applied around the thigh for two hours at either 125 or 350 mmHg. There was an considerable increase of the relative numbers of both large and small fibres as well as changes in the proportions of the types of fibre. The most dramatic percentage change in type of fibre was in the semimembranosus when compressed at 350 mmHg, which showed an increase of the relative frequency of fibres with type 2AB staining characteristics from 10.2% to 18.0% (p < 0.001). Extreme changes in fibre area were found exclusively in semimembranosus and biceps femoris. Most fibres of abnormal size were of type 2, type 2B fibre areas being the most affected. This study shows that morphometry is a valuable tool in the assessment of the more subtle indications of injury. Compression and ischaemia together have a more dramatic effect on muscle morphology and morphometric properties in the non-necrotic regions than ischaemia alone. These data also show that muscles are differentially sensitive to compression and ischaemia. This information may be useful into the understanding of more complex functional deficits observed after the use of tourniquet.

  18. Intramyocardial Injection of siRNAs Can Efficiently Establish Myocardial Tissue-Specific Renalase Knockdown Mouse Model.

    Science.gov (United States)

    Huang, Kun; Liu, Ju; Zhang, Hui; Wang, Jiliang; Li, Huili

    2016-01-01

    Ischaemia/reperfusion (I/R) injury will cause additional death of cardiomyocytes in ischaemic heart disease. Recent studies revealed that renalase was involved in the I/R injury. So, the myocardial tissue-specific knockdown mouse models were needed for the investigations of renalase. To establish the mouse models, intramyocardial injection of siRNAs targeting renalase was performed in mice. The wild distribution and high transfection efficiency of the siRNAs were approved. And the renalase expression was efficiently suppressed in myocardial tissue. Compared with the high cost, time consumption, and genetic compensation risk of the Cre/loxP technology, RNA interference (RNAi) technology is much cheaper and less time-consuming. Among the RNAi technologies, injection of siRNAs is safer than virus. And considering the properties of the I/R injury mouse models, the efficiency and durability of injection with siRNAs are acceptable for the studies. Altogether, intramyocardial injection of siRNAs targeting renalase is an economical, safe, and efficient method to establish myocardial tissue-specific renalase knockdown mouse models.

  19. Transient Heat Conduction

    DEFF Research Database (Denmark)

    Rode, Carsten

    1998-01-01

    Analytical theory of transient heat conduction.Fourier's law. General heat conducation equation. Thermal diffusivity. Biot and Fourier numbers. Lumped analysis and time constant. Semi-infinite body: fixed surface temperature, convective heat transfer at the surface, or constant surface heat flux...

  20. The role of curcumin as an inhibitor of oxidative stress caused by ischaemia re-perfusion injury in tetralogy of Fallot patients undergoing corrective surgery.

    Science.gov (United States)

    Sukardi, Rubiana; Sastroasmoro, Sudigdo; Siregar, Nurjati C; Djer, Mulyadi M; Suyatna, Fransciscus D; Sadikin, Mohammad; Ibrahim, Nurhadi; Rahayuningsih, Sri E; Witarto, Arief B

    2016-03-01

    Cardiopulmonary bypass during tetralogy of Fallot corrective surgery is associated with oxidative stress, and contributes to peri-operative problems. Curcumin has been known as a potent scavenger of reactive oxygen species, which enhances the activity of antioxidants and suppresses phosphorylation of transcription factors involved in inflamation and apoptosis. To evaluate the effects of curcumin as an antioxidant by evaluating the concentrations of malondialdehyde and glutathione, activity of nuclear factor-kappa B, c-Jun N-terminal kinase, caspase-3, and post-operative clinical outcomes. Tetralogy of Fallot patients for corrective surgery were randomised to receive curcumin (45 mg/day) or placebo orally for 14 days before surgery. Malondialdehyde and glutathione concentrations were evaluated during the pre-ischaemia, ischaemia, re-perfusion phases, and 6 hours after aortic clamping-off. Nuclear factor-kappa B, c-Jun N-terminal kinase, and caspase-3, taken from the infundibulum, were assessed during the pre-ischaemia, ischaemia, and re-perfusion phases. Haemodynamic parameters were monitored until day 5 after surgery. In all the observation phases, malondialdehyde and glutathione concentrations were similar between groups. There was no significant difference in nuclear factor-kappa B activity between the groups for three observations; however, in the curcumin group, c-Jun N-terminal kinase significantly decreased from the pre-ischaemia to the re-perfusion phases, and caspase-3 expression was lower in the ischaemia phase. Patients in the curcumin group had lower temperature and better ventricular functions, but no significant differences were found in mechanical ventilation day or length of hospital stay in the two groups. Cardioprotective effects of curcumin may include inhibition of the c-Jun N-terminal kinase pathway and caspase-3 in cardiomyocytes, particularly in the ischaemia phase.

  1. Myocardial perfusion in patients with left bundle branch block and without coronary artery disease

    International Nuclear Information System (INIS)

    Narita, Michihiro; Kurihara, Tadashi; Murano, Kenichi; Usami, Masahisa; Honda, Minoru

    1992-01-01

    For the evaluation of myocardial perfusion in patients with left bundle branch block (LBBB), we performed exercise stress (Ex)-redistribution (RD) myocardial tomography with thallium-201 ( 201 Tl) in 23 patients with LBBB and without coronary artery disease (CAD). Myocardial images in patients with LBBB were compared with those of 9 patients with CAD who showed Ex induced transient septal defect. Bull'-eye maps ( 201 Tl distribution maps at Ex and RD and 201 Tl washout rate [WOR] map) were made from myocardial tomograms. In 23 patients with LBBB, 15 patients (65%) developed myocardial perfusion abnormality. In 10 (67%) of these 15 patients, transient perfusion defect appeared in the entire septum (diffuse type). On the other hand in 5 patients (33%), localized fixed perfusion defect developed at the boundary between septum and anterior wall (focal type). In focal type, every patient had other disease such as hypertension, aortic stenosis or sick sinus syndrome. While in patients with diffuse type, other diseases were observed in 30% (p 201 Tl WOR and 201 Tl uptake ratio of septum to lateral wall indicated that exercise induced septal defect was slighter in diffuse type than CAD. These points might be useful to differentiate whether CAD participates in the septal defect or not in patients with LBBB. (author)

  2. Compressive Transient Imaging

    KAUST Repository

    Sun, Qilin

    2017-04-01

    High resolution transient/3D imaging technology is of high interest in both scientific research and commercial application. Nowadays, all of the transient imaging methods suffer from low resolution or time consuming mechanical scanning. We proposed a new method based on TCSPC and Compressive Sensing to achieve a high resolution transient imaging with a several seconds capturing process. Picosecond laser sends a serious of equal interval pulse while synchronized SPAD camera\\'s detecting gate window has a precise phase delay at each cycle. After capturing enough points, we are able to make up a whole signal. By inserting a DMD device into the system, we are able to modulate all the frames of data using binary random patterns to reconstruct a super resolution transient/3D image later. Because the low fill factor of SPAD sensor will make a compressive sensing scenario ill-conditioned, We designed and fabricated a diffractive microlens array. We proposed a new CS reconstruction algorithm which is able to denoise at the same time for the measurements suffering from Poisson noise. Instead of a single SPAD senor, we chose a SPAD array because it can drastically reduce the requirement for the number of measurements and its reconstruction time. Further more, it not easy to reconstruct a high resolution image with only one single sensor while for an array, it just needs to reconstruct small patches and a few measurements. In this thesis, we evaluated the reconstruction methods using both clean measurements and the version corrupted by Poisson noise. The results show how the integration over the layers influence the image quality and our algorithm works well while the measurements suffer from non-trival Poisson noise. It\\'s a breakthrough in the areas of both transient imaging and compressive sensing.

  3. Dysfunctional vasa vasorum in diabetic peripheral artery obstructive disease with critical lower limb ischaemia.

    Science.gov (United States)

    Orrico, C; Pasquinelli, G; Foroni, L; Muscarà, D; Tazzari, P L; Ricci, F; Buzzi, M; Baldi, E; Muccini, N; Gargiulo, M; Stella, A

    2010-09-01

    To establish whether in diabetic patients with peripheral artery obstructive disease (PAOD) vasa vasorum (vv) neoangiogenesis is altered with increased arterial damage. Thirty-three patients with PAOD and critical lower limb ischaemia, 22 with type II diabetes. Immunohistochemistry for endothelial cell markers (CD34 and von Willebrand Factor); real-time reverse transcription polymerase chain reaction (RT-PCR) to quantify arterial wall expression of vascular endothelial growth factor (VEGF); enzyme-linked immunosorbent assay (ELISA) to assess blood VEGF; flow cytometry to detect circulating endothelial cells (CECs). Patients with PAOD and diabetes have a higher frequency (60% vs. 45%) of advanced atherosclerotic lesions and a significant reduction (p = 0.0003) in CD34(+) capillaries in the arterial media. Adventitial neoangiogenesis was increased equally (CD34(+) and vWF(+)) in all patients. Likewise, all patients have increased CEC and VEGF concentration in the blood as well as in-situ VEGF transcript expression. Patients with PAOD have remarkable arterial damage despite increased in-situ and circulating expression of the pro-angiogenic VEGF; a dysfunctional vv angiogenesis was seen in diabetics which also showed a higher frequency of parietal damage; it is suggested that in diabetic arterial wall, injury is worsened by vv inability to finalise an effective VEGF-driven arterial wall neoangiogenesis. Copyright 2010 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  4. KCC2 expression changes in Diazepam-treated neonatal rats with hypoxia-ischaemia brain damage.

    Science.gov (United States)

    Ma, Jun-Yuan; Zhang, Su-Pei; Guo, Liu-Bin; Li, Yong-Mei; Li, Qiang; Wang, Sai-Qi; Liu, Hong-Min; Wang, Cong

    2014-05-14

    Hypoxia-ischaemia brain damage (HIBD) is a major type of perinatal brain injury in newborns. In this study, we investigate the short- and long-term neuroprotective effects of Diazepam on neonatal rats with HIBD and the potential mechanisms underlying its protective effects. Seven-day-old Sprague-Dawley rats were subjected to left carotid artery ligation followed by a 2-h exposure to 8% oxygen and 92% nitrogen. Diazepam was administered immediately via intraperitoneal (i.p.) injection after inducing HIBD at a dose of 10 mg kg(-1)8h(-1) for three consecutive days. Three days after HIBD, rats were decapitated, and the extent of brain injury was evaluated using 2,3,5-triphenyltetrazolium chloride (TTC) staining. Additionally, the expression of Potassium-chloride cotransporter-2 (KCC2) was analysed using real-time PCR, Western blot analysis and immunohistochemistry. Three weeks after HIBD, rats were subjected to the Morris water maze (MWM) test and the locomotor activity test to determine the long-term therapeutic effects of Diazepam. We observed that the volume of infarction in the Diazepam group was significantly less (PDiazepam rats improved significantly compared with the untreated rats (PDiazepam appears to attenuate HIBD and can efficiently improve the long-term learning and memory capabilities of the animal. A potential mechanism underlying these effects may involve preventing the decrease in KCC2 expression. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. The relationship between ischaemia-modified albumin and good coronary collateral circulation.

    Science.gov (United States)

    Gök, Murat; Kundi, Harun; Kızıltunç, Emrullah; Topcuoglu, Canan; Ornek, Ender

    2018-01-01

    It is important to determine the grade of the coronary collateral circulation (CCC) in patients with stable coronary artery disease. In this study, we aimed to investigate the relationship between the ischaemia-modified albumin (IMA) level and good CCC. A total of 95 patients with coronary angiography and at least one epicardial coronary artery obstruction were included in the study. The Rentrop classification was used with CCC grading, where 0 and 1 were defined as poor collateral, and 2 and 3 were defined as good collateral. The IMA level of the patients was measured using an enzyme-linked immunosorbent assay (ELISA). The receiver-operating characteristic curve was used to show the sensitivity and specificity of IMA levels and the optimal cut-off value for predicting good CCC. The multiple logistic regression analysis revealed that the IMA level in the good CCC group was higher (p good CCC group (p good CCC level, and this shows good CCC with 70.2% sensitivity and 60.3% specificity. The IMA level could serve as a simple and useful predictor of well-developed CCC.

  6. VAC therapy to promote wound healing after surgical revascularisation for critical lower limb ischaemia.

    Science.gov (United States)

    De Caridi, Giovanni; Massara, Mafalda; Greco, Michele; Pipitò, Narayana; Spinelli, Francesco; Grande, Raffaele; Butrico, Lucia; de Franciscis, Stefano; Serra, Raffaele

    2016-06-01

    Vacuum-assisted closure (VAC) therapy is a new emerging non-invasive system in wound care, which speeds up wound healing by causing vacuum, improving tissue perfusion and suctioning the exudates, and facilitating the removal of bacteria from the wound. The application of sub-atmospheric pressure on the lesions seems to alter the cytoskeleton of the cells on the wound bed, triggering a cascade of intracellular signals that increase the rate of cell division and subsequent formation of granulation tissue. The aim of this study is to analyse the results of VAC therapy used as an adjuvant therapy for the treatment of foot wounds in patients affected by critical limb ischaemia (CLI) (Rutherford 6 class) after distal surgical revascularisation, to promote and accelerate the healing of ulcers. Twenty-nine patients (20 males, 9 females; mean age 68·4) affected by CLI of Rutherford 6 class, after surgical revascularisation of the lower limb, underwent VAC therapy in order to speed up wound healing. Complete wound healing was achieved in 19 patients (65·51%), in an average period of 45·4 ± 25·6 days. VAC therapy is a valid aid, after surgical revascularisation, to achieve rapid healing of foot lesions in patients with CLI. © 2014 The Authors. International Wound Journal © 2014 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  7. Transient receptor potential vanilloid 1 (TRPV1), TRPV4, and the kidney

    DEFF Research Database (Denmark)

    Kassmann, M.; Harteneck, C.; Zhu, Z.

    2013-01-01

    channel agonists such as 20-HETE, phospholipase C and phosphatidylinositide 3-kinase (PI3 kinase). We review important roles of TRPV1 and TRPV4 in kidney physiology and renal ischaemia reperfusion injury; further studies are warranted to address renoprotective mechanism of vanilloid receptors in ischaemic......Recent preclinical data indicate that activators of transient receptor potential channels of the vanilloid receptor subtype 1 (TRPV1) may improve the outcome of ischaemic acute kidney injury (AKI). The underlying mechanisms are unclear, but may involve TRPV1 channels in dorsal root ganglion...... neurones that innervate the kidney. Recent data identified TRPV4, together with TRPV1, to serve as major calcium influx channels in endothelial cells. In these cells, gating of individual TRPV4 channels within a four-channel cluster provides elementary calcium influx (calcium sparklets) to open calcium...

  8. Explosive and radio-selected Transients: Transient Astronomy with ...

    Indian Academy of Sciences (India)

    40

    SKA), large samples of explosive transients are expected to be discovered. Radio wavelengths, especially in commensal survey mode, are particularly well suited for uncovering the complex transient phenomena. This is because ob- servations ...

  9. Depression following myocardial infarction

    DEFF Research Database (Denmark)

    Larsen, Karen Kjær

    2013-01-01

    Myocardial infarction (MI) is a severe life event that is accompanied by an increased risk of depression. Mounting evidence suggests that post-MI depression is associated with adverse outcomes, but the underlying mechanisms of this association remain unclear, and no previous studies have examined...... whether the mental burden of MI is so heavy that it increases the risk of suicide. Although post-MI depression is common and burdensome, the condition remains under-recognised and under-treated. The development of new strategies to improve the quality of care for people with post-MI depression requires...... thorough understanding of the mechanisms that influence the prognosis as well as knowledge of the present care provided. The purpose of this PhD thesis is accordingly subdivided into four specific aims: 1. To estimate the prevalence of depression in people with MI after three months, and to estimate...

  10. Transient Astrophysics Probe

    Science.gov (United States)

    Camp, Jordan; Transient Astrophysics Probe Team

    2018-01-01

    The Transient Astrophysics Probe (TAP) is a wide-field multi-wavelength transient mission proposed for flight starting in the late 2020s. The mission instruments include unique “Lobster-eye” imaging soft X-ray optics that allow a ~1600 deg2 FoV; a high sensitivity, 1 deg2 FoV soft X-ray telescope; a 1 deg2 FoV Infrared telescope with bandpass 0.6-3 micron; and a set of 8 NaI gamma-ray detectors. TAP’s most exciting capability will be the observation of tens per year of X-ray and IR counterparts of GWs involving stellar mass black holes and neutron stars detected by LIGO/Virgo/KAGRA/LIGO-India, and possibly several per year X-ray counterparts of GWs from supermassive black holes, detected by LISA and Pulsar Timing Arrays. TAP will also discover hundreds of X-ray transients related to compact objects, including tidal disruption events, supernova shock breakouts, and Gamma-Ray Bursts from the epoch of reionization.

  11. Metastability of transient states

    Science.gov (United States)

    Rafailov, Michael K.

    2017-05-01

    High intensity ultrashort pulse causes dramatic perturbations in electronic structure of condensed matter. In the same time energy in high intensity single pulse may not be sufficient to disrupt sample thermal equilibrium. Interesting experimental results in ultrashort pulse photo-excited solids have been reported recently on transient athermal phenomena induced by ultrashort high intensity low energy pulse - phenomena related to both athermal phase transitions and athermal state changes. Athermal non-equilibrium of electronic system - and induced changes in magnetic and optical states, may exist only for a period of time comparable to excited carriers' relaxation time. That time is not sufficient for emerging application ranging from light induced superconductivity to infrared countermeasures. While single pulse interaction with condensed matter leading to transit state appearance is well observed, documented, and, to some extends, explained, one of the major problem is to maintain meta-stability of such transient states. Metastability of athermal non-equilibrium that could last well beyond electronic system relaxation time. The objective of this paper is to discuss some issues and approaches to meta-stability of transient states induced by ultrashort pulses in condensed matter.

  12. Transient or permanent fisheye views

    DEFF Research Database (Denmark)

    Jakobsen, Mikkel Rønne; Hornbæk, Kasper

    2012-01-01

    Transient use of information visualization may support specific tasks without permanently changing the user interface. Transient visualizations provide immediate and transient use of information visualization close to and in the context of the user’s focus of attention. Little is known, however, ...

  13. Neuroprotective effects of andrographolide in a rat model of permanent cerebral ischaemia

    Science.gov (United States)

    Chan, Su Jing; Wong, WS Fred; Wong, Peter TH; Bian, Jin-Song

    2010-01-01

    BACKGROUND AND PURPOSE Andrographolide is a diterpenoid lactone isolated from a traditional medicinal herb, Andrographis paniculata. It possesses potent anti-inflammatory activity. The present study examined potential therapeutic effects of andrographolide on cerebral ischaemia using a rat model with permanent middle cerebral artery occlusion (pMCAO). EXPERIMENTAL APPROACH The MCA in rats was permanently occluded (by cautery), and 24 h later neurological effects were assessed with behavioural scores. Infarct volume and microglial activation were determined histologically. The p65 form of the transcription factor, nuclear factor-κB (NF-κB), was measured by Western blot, and cytokines by immunoassay of brain extracts. KEY RESULTS Andrographolide, given i.p. 1 h after pMCAO, reduced infarct volume with a maximum reduction of approximately 50% obtained at 0.1 mg·kg−1. Neurological deficits were also reduced by andrographolide, reflecting a correlation between infarct volume and neurological deficits. pMCAO was found to induce activation of microglia and elevate tumour necrosis factor (TNF)-α, interleukin (IL)-1β and prostaglandin (PG)E2 in the ischaemic brain areas. Andrographolide (0.1 mg·kg−1) significantly attenuated or abolished these effects. In addition, andrographolide suppressed the translocation of p65 from cytosol to nucleus, indicating reduced NF-κB activation. CONCLUSIONS AND IMPLICATIONS Andrographolide exhibited neuroprotective effects, with accompanying suppression of NF-κB and microglial activation, and reduction in the production of cytokines including TNF-α and IL-1β, and pro-inflammatory factors such as PGE2. Our findings suggest that andrographolide may have therapeutic value in the treatment of stroke. PMID:20880404

  14. Results of bypass graft surgery after prior angioplasty in critical limb ischaemia treatment.

    Science.gov (United States)

    Cury, Marcus Vinícius Martins; Brochado-Neto, Francisco Cardoso; Matielo, Marcelo Fernando; de Athayde Soares, Rafael; Sarpe, Anna Karina Paiva; Sacilotto, Roberto

    2016-01-01

    The aim of this study was to determine the outcomes of primary bypass graft surgery (BGS) compared to BGS after failed angioplasty (PTA). Between January 2007 and January 2014, we performed 136 BGSs exclusively for the treatment of critical limb ischaemia. Two cohorts were identified: 1) primary BGS (n = 102; group I), and 2) BGS after prior PTA (n = 34; group II). Data were analysed retrospectively and the primary endpoints were the rates of secondary patency, amputation-free survival, freedom from major adverse outcomes (graft occlusion, amputation, or death), and overall survival, which were assessed with the Kaplan-Meier method. Both groups were comparable with a predominance of Rutherford's category 5 ischaemic lesions (73.3 %). Most patients had extensive TASC D athe-rosclerotic disease (83.6 %), and the main conduit was the greater saphenous vein (58.1 %). The mean follow-up time was 36.2 months. The 3-year secondary patency rates were better for group I (64.3 % vs 49.6 %; P = 0.04). During the same period, the amputation-free survival rates were similar between the groups (77.4 % vs 74.5 %; P = 0.59). For multivariate Cox regression analysis, BGS after prior PTA was the only factor associated with re-intervention for limb salvage (hazard ratio = 2.39; CI 95 % = 1.19 - 4.80; P = 0.02). At the 3-year point, there were no differences in the overall survival rates (72.6 % vs 70 %; P = 0.97), but the proportion of patients without adverse outcomes was higher in group I (37.3 % vs 13.4 %; P = 0.007). Although secondary patency was better after primary BGS, the amputation-free and overall survival rates support the use of BGS after prior PTA.

  15. Influence of Androgen Receptor in Vascular Cells on Reperfusion following Hindlimb Ischaemia.

    Directory of Open Access Journals (Sweden)

    Junxi Wu

    Full Text Available Studies in global androgen receptor knockout (G-ARKO and orchidectomised mice suggest that androgen accelerates reperfusion of the ischaemic hindlimb by stimulating angiogenesis. This investigation used novel, vascular cell-specific ARKO mice to address the hypothesis that the impaired hindlimb reperfusion in G-ARKO mice was due to loss of AR from cells in the vascular wall.Mice with selective deletion of AR (ARKO from vascular smooth muscle cells (SM-ARKO, endothelial cells (VE-ARKO, or both (SM/VE-ARKO were compared with wild type (WT controls. Hindlimb ischaemia was induced in these mice by ligation and removal of the femoral artery. Post-operative reperfusion was reduced in SM-ARKO and SM/VE-ARKO mice. Immunohistochemistry indicated that this was accompanied by a reduced density of smooth muscle actin-positive vessels but no change in the density of isolectin B4-positive vessels in the gastrocnemius muscle. Deletion of AR from the endothelium (VE-ARKO did not alter post-operative reperfusion or vessel density. In an ex vivo (aortic ring culture model of angiogenesis, AR was not detected in vascular outgrowths and angiogenesis was not altered by vascular ARKO or by exposure to dihydrotestosterone (DHT 10-10-10-7M; 6 days.These results suggest that loss of AR from vascular smooth muscle, but not from the endothelium, contributes to impaired reperfusion in the ischaemic hindlimb of G-ARKO. Impaired reperfusion was associated with reduced collateral formation rather than reduced angiogenesis.

  16. The role of mast cells and fibre type in ischaemia reperfusion injury of murine skeletal muscles

    Directory of Open Access Journals (Sweden)

    Bortolotto Susan K

    2004-09-01

    Full Text Available Abstract Background Ischaemia reperfusion (IR injury of skeletal muscle, is a significant cause of morbidity following trauma and surgical procedures, in which muscle fibre types exhibit different susceptibilities. The relative degree of mast cell mediated injury, within different muscle types, is not known. Methods In this study we compared susceptibility of the fast-twitch, extensor digitorum longus (EDL, mixed fast/slow-twitch gastrocnemius and the predominately slow-twitch soleus, muscles to ischemia reperfusion (IR injury in four groups of mice that harbour different mast cell densities; C57/DBA mast cell depleted (Wf/Wf, their heterozygous (Wf/+ and normal littermates (+/+ and control C57BL/6 mice. We determined whether susceptibility to IR injury is associated with mast cell content and/or fibre type and/or mouse strain. In experimental groups, the hind limbs of mice were subjected to 70 minutes warm tourniquet ischemia, followed by 24 h reperfusion, and the muscle viability was assessed on fresh whole-mount slices by the nitroblue tetrazolium (NBT histochemical assay. Results Viability was remarkably higher in the Wf/Wf strain irrespective of muscle type. With respect to muscle type, the predominately slow-twitch soleus muscle was significantly more resistant to IR injury than gastrocnemius and the EDL muscles in all groups. Mast cell density was inversely correlated to muscle viability in all types of muscle. Conclusion These results show that in skeletal muscle, IR injury is dependent upon both the presence of mast cells and on fibre type and suggest that a combination of preventative therapies may need to be implemented to optimally protect muscles from IR injury.

  17. Complement peptide C3a stimulates neural plasticity after experimental brain ischaemia.

    Science.gov (United States)

    Stokowska, Anna; Atkins, Alison L; Morán, Javier; Pekny, Tulen; Bulmer, Linda; Pascoe, Michaela C; Barnum, Scott R; Wetsel, Rick A; Nilsson, Jonas A; Dragunow, Mike; Pekna, Marcela

    2017-02-01

    Ischaemic stroke induces endogenous repair processes that include proliferation and differentiation of neural stem cells and extensive rewiring of the remaining neural connections, yet about 50% of stroke survivors live with severe long-term disability. There is an unmet need for drug therapies to improve recovery by promoting brain plasticity in the subacute to chronic phase after ischaemic stroke. We previously showed that complement-derived peptide C3a regulates neural progenitor cell migration and differentiation in vitro and that C3a receptor signalling stimulates neurogenesis in unchallenged adult mice. To determine the role of C3a-C3a receptor signalling in ischaemia-induced neural plasticity, we subjected C3a receptor-deficient mice, GFAP-C3a transgenic mice expressing biologically active C3a in the central nervous system, and their respective wild-type controls to photothrombotic stroke. We found that C3a overexpression increased, whereas C3a receptor deficiency decreased post-stroke expression of GAP43 (P plasticity, in the peri-infarct cortex. To verify the translational potential of these findings, we used a pharmacological approach. Daily intranasal treatment of wild-type mice with C3a beginning 7 days after stroke induction robustly increased synaptic density (P neural plasticity and intranasal treatment with C3a receptor agonists is an attractive approach to improve functional recovery after ischaemic brain injury. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  18. Correction of biochemical and functional disorders in brain ischaemia with laser therapy

    Science.gov (United States)

    Musienko, Julia I.; Nechipurenko, Natalia I.; Vasilevskaya, Ludmila A.

    2005-08-01

    Application of intravenous laser irradiation of blood (ILIB) is considered to be the most effective method of laser therapy and its application is expedient pathogenetically in the ischemic disturbances. The aim of this study is to investigate ILIB influence with red helium-neon laser (HNL) with 630 nm wavelength and different powers on blood oxygen transport (BOT), cerebral and dermal microhaemodynamics (MGD), hydro-ion balance in normal rabbits and after modeling of local ischemia of brain (LIB). Experimental cerebral ischemia is characterized by development of BOT disturbance, ionic disbalance and edema in the ischemic brain region. Microcirculation disturbances with worsening of the cerebral and dermal MHD were revealed. ILIB with HNL radiation of 2.5 and 4.5 mW powers provokes dehydratation of brain structure alone with the K+, Na+ concentration decreasing and hemoglobin-oxygen affinity increasing in intact group of animals. There was not revealed marked changes of cerebral MHD condition here. Using of ILIB in rabbits after LIB contributes for improving function of BOT, normalizing of water content in all cerebral structures compared to operated animals. Preventive ILIB provoked improvement of speckl-optical parameters and marked protective effect on microhaemodynamics processes in superficial brain structures. HNL radiation with 1.0 mW power results in worsening of oxygen transport, cerebral and skin MHD, hydro-ion homeostasis in animals with LIB modeling. Thus, laser haemotherapy contributes for improving of hydro-ion status, blood oxygen transport and cerebral microcirculation in brain ischemia, what allows considering that helium-neon radiation with the pointed regimen is substantiated pathogenetically in brain ischaemia.

  19. An investigation on cardioprotective potential of Marrubium vulgare aqueous fraction against ischaemia-reperfusion injury in isolated rat heart.

    Science.gov (United States)

    Garjani, A; Tila, D; Hamedeyazdan, S; Vaez, H; Rameshrad, M; Pashaii, M; Fathiazad, F

    2017-01-01

    The aim of this study was to evaluate the cardioprotective effects of aqueous fraction of Marrubium vulgare hydroalcoholic extract on cardiac parameters in ischaemic-reperfused isolated rat hearts. The aerial parts of the plant were extracted with methanol 70% by maceration. The water-soluble portion of the total hydroalcoholic extract was prepared with liquid-liquid extraction (LLE). Afterwards, the antioxidant activity, total phenolic and flavonoids content of the aqueous fraction were determined. In order to evaluate the effects of the aqueous fraction on cardiac parameters and ischaemia-reperfusion (I/R) injury, the Langendroff method was used on male Wistar rats. Harvested hearts were cannulated immediately to the Langendroff apparatus and subjected into 30 min regional ischaemia and 2 h reperfusion, either by a modified Krebs-Henseleit buffer (KHB) solution or enriched KHB solution with plant extract (10, 20, 40 μg/mL). The aqueous fraction was found to be a scavenger of DPPH radical with RC50 value of 47 μg/mL. The total phenolic and flavonoids content of the fraction was 6.05 g gallic acid equivalent and 36.13 mg quercetin equivalent per 100 g of dry plant material. In addition, 40 μg/mL of Marrubium vulgare aqueous fraction significantly decreased infarct size in comparison to control group. All doses considerably reduced the total ventricular ectopic beats during 30 min of ischaemia. The extract at dose of 40 μg/mL noticeably decreased the arrhythmias during the first 30 min of reperfusion. The results of the study indicated aqueous fraction of Marrubium vulgare possesses a protective effect against I/R injuries in isolated rat hearts.

  20. Flow motion waves with high and low frequency in severe ischaemia before and after percutaneous transluminal angioplasty.

    Science.gov (United States)

    Hoffmann, U; Schneider, E; Bollinger, A

    1990-09-01

    STUDY OF OBJECTIVE: The aim was to evaluate skin flux and prevalence of low and high frequency flow motion waves in patients with severe ischaemia due to peripheral arterial occlusive disease before and after percutaneous transluminal angioplasty (PTA) with and without local thrombolysis. Flow motion was recorded by the laser Doppler technique at the dorsum of the foot before, one day, and one month after PTA. The results were separately analysed in patients with successful and unsuccessful treatment. 18 patients with rest pain or incipient gangrene were included. Mean pretreatment systolic ankle pressure was 55.8(SD 25.5) mm Hg, and mean transcutaneous PO2 at 43 degrees C was 5.2(9.4) mm Hg. Arteriography revealed relevant stenoses or occlusions of the femoropopliteal and calf arteries. Before treatment two patterns of flow motion with characteristic frequency ranges were observed at the foot dorsum and at a probe temperature of 32 degrees C: low frequency (LF) waves with a mean frequency of 2.2(0.5) cycles.min-1 and a mean amplitude of 0.73(0.42) arbitrary units (AU) and high frequency (HF) waves with a mean frequency of 22.6(4.2) cycles.min-1 and a mean amplitude of 0.39(0.33) AU. PTA was successful in 11 of the 18 patients. After successful treatment, prevalence of HF waves decreased from 10/11 to 4/11 cases (p less than 0.001), but remained nearly unchanged after failed procedure. Prevalence of LF waves before and after PTA did not differ significantly. Our data support the hypothesis that HF waves represent a reaction of skin microcirculation to severe ischaemia. With reference to animal studies it is proposed that HF waves originate from terminal arterioles. They may function as a compensatory mechanism of flow regulation involved in pathophysiology of ischaemia.

  1. Effect of rosiglitazone on cardiac electrophysiology, infarct size and mitochondrial function in ischaemia and reperfusion of swine and rat heart.

    Science.gov (United States)

    Palee, Siripong; Weerateerangkul, Punate; Surinkeaw, Sirirat; Chattipakorn, Siriporn; Chattipakorn, Nipon

    2011-08-01

    Rosiglitazone, a peroxisome proliferator-activated receptor γ agonist, has been used to treat type 2 diabetes. Despite debates regarding its cardioprotection, the effects of rosiglitazone on cardiac electrophysiology are still unclear. This study determined the effect of rosiglitazone on ventricular fibrillation (VF) incidence, VF threshold (VFT), defibrillation threshold (DFT) and mitochondrial function during ischaemia and reperfusion. Twenty-six pigs were used. In each pig, either rosiglitazone (1 mg kg(-1)) or normal saline solution was administered intravenously for 60 min. Then, the left anterior descending coronary artery was ligated for 60 min and released to promote reperfusion for 120 min. The cardiac electrophysiological parameters were determined at the beginning of the study and during the ischaemia and reperfusion periods. The heart was removed, and the area at risk and infarct size in each heart were determined. Cardiac mitochondria were isolated for determination of mitochondrial function. Rosiglitazone did not improve the DFT and VFT during the ischaemia-reperfusion period. In the rosiglitazone group, the VF incidence was increased (58 versus 10%) and the time to the first occurrence of VF was decreased (3 ± 2 versus 19 ± 1 min) in comparison to the vehicle group (P < 0.05). However, the infarct size related to the area at risk in the rosiglitazone group was significantly decreased (P < 0.05). In the cardiac mitochondria, rosiglitazone did not alter the level of production of reactive oxygen species and could not prevent mitochondrial membrane potential changes. Rosiglitazone increased the propensity for VF, and could neither increase defibrillation efficacy nor improve cardiac mitochondrial function.

  2. Knockdown of apoptosis signal-regulating kinase 1 affects ischaemia-induced astrocyte activation and glial scar formation.

    Science.gov (United States)

    Cheon, So Yeong; Cho, Kyoung Joo; Song, Juhyun; Kim, Gyung Whan

    2016-04-01

    Reactive astrocytes play an essential role in determining the tissue response to ischaemia. Formation of a glial scar can block the neuronal outgrowth that is required for restoration of damaged tissue. Therefore, regulation of astrocyte activation is important; however, the mediator of this process has not been fully elucidated. Apoptosis signal-regulating kinase 1 (ASK1) is an early responder to oxidative stress, and plays a pivotal role in the intracellular signalling pathway of apoptosis, inflammation, and differentiation. To confirm whether ASK1 mediates astrocyte activation and leads to glial scar formation after cerebral ischaemia, we conducted in vivo and in vitro experiments. C57BL/6 mice were subjected to occlusion of the middle cerebral artery, and astrocyte cultures were exposed to oxygen-glucose deprivation. After silencing of ASK1 , astrocyte-associated genes were downregulated, as seen with the use of microarrays. The glial fibrillary acidic protein (GFAP) level was decreased, and correlated with the reduction in the ASK1 level. In astrocytes, reduction in the ASK1 level decreased the activity of the p38 pathway, and the levels of transcription factors for GFAP and GFAP transcripts after hypoxia. In the chronic phase, ASK1 depletion reduced glial scar formation and conserved neuronal structure, which may lead to better functional recovery. These data suggest that ASK1 may be an important mediator of ischaemia-induced astrocyte activation and scar formation, and could provide a potential therapeutic target for treatment after ischaemic stroke. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  3. Daytime variation of perioperative myocardial injury in cardiac surgery and its prevention by Rev-Erbα antagonism: a single-centre propensity-matched cohort study and a randomised study.

    Science.gov (United States)

    Montaigne, David; Marechal, Xavier; Modine, Thomas; Coisne, Augustin; Mouton, Stéphanie; Fayad, Georges; Ninni, Sandro; Klein, Cédric; Ortmans, Staniel; Seunes, Claire; Potelle, Charlotte; Berthier, Alexandre; Gheeraert, Celine; Piveteau, Catherine; Deprez, Rebecca; Eeckhoute, Jérome; Duez, Hélène; Lacroix, Dominique; Deprez, Benoit; Jegou, Bruno; Koussa, Mohamed; Edme, Jean-Louis; Lefebvre, Philippe; Staels, Bart

    2018-01-06

    On-pump cardiac surgery provokes a predictable perioperative myocardial ischaemia-reperfusion injury which is associated with poor clinical outcomes. We determined the occurrence of time-of-the-day variation in perioperative myocardial injury in patients undergoing aortic valve replacement and its molecular mechanisms. We studied the incidence of major adverse cardiac events in a prospective observational single-centre cohort study of patients with severe aortic stenosis and preserved left ventricular ejection fraction (>50%) who were referred to our cardiovascular surgery department at Lille University Hospital (Lille, France) for aortic valve replacement and underwent surgery in the morning or afternoon. Patients were matched into pairs by propensity score. We also did a randomised study, in which we evaluated perioperative myocardial injury and myocardial samples of patients randomly assigned (1:1) via permuted block randomisation (block size of eight) to undergo isolated aortic valve replacement surgery either in the morning or afternoon. We also evaluated human and rodent myocardium in ex-vivo hypoxia-reoxygenation models and did a transcriptomic analysis in myocardial samples from the randomised patients to identify the signalling pathway(s) involved. The primary objective of the study was to assess whether myocardial tolerance of ischaemia-reperfusion differed depending on the timing of aortic valve replacement surgery (morning vs afternoon), as measured by the occurrence of major adverse cardiovascular events (cardiovascular death, myocardial infarction, and admission to hospital for acute heart failure). The randomised study is registered with ClinicalTrials.gov, number NCT02812901. In the cohort study (n=596 patients in matched pairs who underwent either morning surgery [n=298] or afternoon surgery [n=298]), during the 500 days following aortic valve replacement, the incidence of major adverse cardiac events was lower in the afternoon surgery group than

  4. Focal ischaemia caused by instability of cerebrovascular tone during attacks of hemiplegic migraine. A regional cerebral blood flow study

    DEFF Research Database (Denmark)

    Friberg, L; Olsen, T S; Roland, P E

    1987-01-01

    During the course of hemiplegic migraine in 3 patients, changes in regional cerebral blood flow (rCBF) were recorded by the intracarotid 133Xe method and a 254 multidetector camera covering one hemisphere. The rCBF measurements were performed in conjunction with cerebral angiography. During...... cerebral vessels (arterioles) alternating with a normal calibre for these vessels and/or short periods of vasodilatation. It is considered to be a primary pathological condition of the vessels. When vasoconstriction was present the blood flow decreased to values consistent with ischaemia, which...

  5. The hyperventilation-induced ischaemia model in human neuropharmacology: neurophysiological and psychometric studies of aniracetam and 3-OH aniracetam.

    Science.gov (United States)

    Kraaier, V; van Huffelen, A C; Wieneke, G H

    1989-01-01

    Standardized hyperventilation in young subjects induces changes in the EEG, a decrease in the velocity of the cerebral blood flow and a decline in cognitive performance, which are comparable to those occurring in patients with cerebral ischaemia. The anti-ischaemic properties of aniracetam and 3-OH aniracetam were tested in this model. A single oral dose of 3-OH aniracetam 1500 mg appeared to have the most pronounced effect on hyperventilation-induced EEG changes and cognitive deterioration. The test drugs had no effect on the heart rate or blood flow velocity. The effects agree with those of other drugs classified as noötropics.

  6. Cortical spreading ischaemia is a novel process involved in ischaemic damage in patients with aneurysmal subarachnoid haemorrhage

    DEFF Research Database (Denmark)

    Dreier, Jens P; Major, Sebastian; Manning, Andrew

    2009-01-01

    -invasive detection of CSD. Low-frequency vascular fluctuations (LF-VF) (f detectable by functional imaging methods, are determined by the brain's resting neuronal activity. CSD provides a depolarization block of the resting activity, recorded electrophysiologically as spreading depression of high...... the differentiation of progressive ischaemia and repair phases in a fashion similar to that shown previously for spreading depressions of high-frequency-electrocorticography activity. In conclusion, it is suggested that (i) CSI is a novel human disease mechanism associated with lesion development and a potential...

  7. Spinal ischaemia after thoracic endovascular aortic repair with left subclavian artery sacrifice: is there a critical stent graft length?

    Science.gov (United States)

    Kari, Fabian A; Saravi, Babak; Krause, Sonja; Puttfarcken, Luisa; Wittmann, Karin; Förster, Katharina; Rylski, Bartosz; Maier, Sven; Göbel, Ulrich; Siepe, Matthias; Czerny, Martin; Beyersdorf, Friedhelm

    2017-08-24

    Thoracic endovascular aortic repair (TEVAR) is used for treatment of thoracic aortic pathologies, but the covered stent graft can induce spinal ischaemia depending on the length used. The left subclavian artery contributes to spinal cord collateralization and is frequently occluded by the stent graft. Our objective was to investigate the impact of covered stent graft length on the risk of spinal ischaemia in the setting of left subclavian artery sacrifice. Twenty-six pigs (German country race, mean body weight 36 ± 4 kg) underwent simulated descending aortic TEVAR via left lateral thoracotomy, with left subclavian artery and thoracic segmental artery occlusion in normothermia. Animals were assigned to treatment groups according to simulated stent graft length: TEVAR to T8 ( n  = 4), TEVAR to T9 ( n  = 4), TEVAR to T10 ( n  = 4), TEVAR to T11 ( n  = 7) and TEVAR to T12 ( n  = 1) and a sham group ( n  = 6). End points included spinal cord perfusion pressure, cerebrospinal fluid pressure and spinal cord blood flow using fluorescent microspheres. There were no group differences in spinal cord perfusion pressure drop or in spinal cord perfusion pressure regeneration potential at 3 h after the procedure: from a baseline average of 75 mmHg (95% confidence interval 71-83 mmHg) to 73 mmHg (67-75 mmHg) at 3 h in Group T10 versus from a baseline average of 67 mmHg (95% CI 50-81 mmHg) to 65 mmHg (95% confidence interval 48-81 mmHg) in Group T8. There were no differences in the spinal cord blood flow courses over time in the different groups nor was there any difference in cerebrospinal fluid pressure levels and cerebrospinal fluid pressure dynamics between groups. However, we did observe local blood flow distribution to the spinal cord that was inhomogeneous depending on the distance between the simulated stent graft end and the first thoracic anterior radiculomedullary artery. The risk of spinal ischaemia after serial

  8. Myocardial scintigraphy in the diagnosis of myocardial contusion

    Energy Technology Data Exchange (ETDEWEB)

    Terashima, Masayoshi; Shinoda, Mitsutaka; Iwama, Hiroshi; Hirama, Hisao; Hoshino, Toshiaki; Urabe, Shinpei [Central Aizu General Hospital, Fukushima (Japan); Meguro, Taiichiroh

    1996-04-01

    To assess the clinical value of a new fatty acid imaging tracer, {sup 123}I-{beta}-methyl iodophenyl pentadecanoic acid (BMIPP), I-BMIPP and thallium-201 (Tl) dual imaging was performed at rest in fifteen patients with mild blunt chest trauma (mean AIS thoracic 1.4{+-}0.51, mean ISS 6.47{+-}3.50, mean RTS 7.69{+-}0.43). All patients were prospectively evaluated on the basis of serial electrocardiograms (ECG) and cardiac enzyme studies (total CPK). Tl and BMIPP dual scintigrams were performed within 10 days following admission. SPECT images were divided into seven segments, and the segmental images were visually scored according to tracer uptake on a 3 (severely decreased tracer uptake) to 0 (normal) scale. Nine patients had scintigraphic defects and were considered to have a myocardial contusion. ECG findings, AIS, ISS, and CPK levels failed to distinguish between scintigraphically positive patients and scintigraphically negative patients. Five of the 14 hypoperfused segments on BMIPP imaging, showed normal Tl uptake, one showed lower BMIPP uptake than Tl, and the remaining eight showed similar distribution of both tracers. The mismatch between tracer uptake on BMIPP images and Tl images was thought to reflect impaired myocardial fatty acid metabolism. Thus, mild blunt chest trauma results in a higher frequency of traumatic myocardial injury than previously recognized, and BMIPP is a promising radio-pharmaceutical for evaluating impaired myocardial fatty acid metabolism in patients with myocardial contusion. (author).

  9. Reduced response to activated protein C is associated with risk of stroke and transient ischaemic attack (abstract)

    NARCIS (Netherlands)

    Bom, J.G. van der; Bots, M.L.; Haverkate, F.; Slagboom, P.E.; Meijer, P.; Hofman, A.; Grobbee, D.E.; Kluft, C.

    1996-01-01

    Objective: To investigate the association of activated protein C (APC) response and of the factor V Leiden mutation with myocardial infarction, stroke and transient ischémie attack. Design: Population-based case control study. Setting: A district of Rotterdam, the Netherlands. Participants: From the

  10. Myocardial perfusion and left ventricular function during exercise evaluated by 201Tl myocardial scintigraphy and 99mTc radionuclide ventriculography in patients treated with PTCA

    International Nuclear Information System (INIS)

    Honda, Toshio; Jo, Tadafumi; Doiuchi, Junji

    1992-01-01

    To evaluate the effects of percutaneous transluminal coronary angioplasty (PTCA), we investigated myocardial ischemia and left ventricular function during exercise before and after successful PTCA in 30 patients. We used extent and severity scores of 201 thallium ( 201 Tl) exercise myocardial scintigraphy to assess myocardial ischemia and determined global and regional left ventricular ejection fraction (EF and REF) of 99m Tc-RBC exercise radionuclide ventriculography to assess left ventricular function. The extent and severity scores of stress images were significantly less after PTCA than before PTCA. The scores of the redistribution images were unchanged before and after PTCA. Global EF during exercise was significantly higher after PTCA than before PTCA. There was no difference in resting global EF between before and after PTCA. Myocardial ischemia induced by exercise was semi-quantitatively analyzed as transient perfusion defect with severity score. Severity score was significantly less after PTCA than before PTCA. ΔEF, which was obtained by subtraction of resting global EF from exercise one, was significantly higher after PTCA than before PTCA. However, the degree of improvement in myocardial ischemia and left ventricular function varied from patient to patient. In 17 patients with one-vessel left anterior descending artery disease, ΔREF, which was determined by subtracting resting regional EF from exercise one, was significantly higher in septal and apical segments after PTCA than before PTCA. Myocardial ischemia and left ventricular function under exercise were alleviated by PTCA. However, the degree of improvement varied from patient to patient and it might have been affected by various factors including coronary dissection, edema, thrombus, restenosis, spasm, side branch stenosis or occlusion, distal thrombus, and myocardial hibernation. (author)

  11. Adenosine technetium-99m sestamibi single-photon emission tomography for the assessment of jeopardized myocardium early after acute myocardial infarction. Paradoxical scintigraphic underestimation of jeopardized myocardium in patients with a severe infarct-related stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Claeys, M.J.; Rademakers, F.E.; Vrints, C.J.; Snoeck, J.P. [Department of Cardiology, Antwerp University Hospital, Edegem (Belgium); Blockx, P.P. [Department of Nuclear Medicine, Antwerp University Hospital, Edegem (Belgium)

    1997-09-01

    In 51 patients with a recent (<1 month) myocardial infarction, adenosine {sup 99m}Tc-sestamibi single-photon emission tomography (SPET) and dobutamine stress echocardiography (DSE) were performed and correlated with the presence of significant coronary artery stenosis on quantitative coronary angiography. Regional perfusion activity was analysed semi-quantitatively (score 0-4) on a 13-segment left ventricular model. DSE was used for the estimation of the infarct size (low-dose DSE) and for concomitant evaluation of ischaemia (high-dose DSE). A reversible perfusion defect within the infarct region was observed in 20 of the 37 patients with a significant infarct-related lesion (sensitivity of 54%) and only in one patient without a significant infarct-related lesion (specificity of 93%). Further analysis revealed that the scintigraphic assessment of jeopardized myocardium was fairly good in patients with a moderate (DS 51%-64%) infarct-related stenosis but was inadequate in patients with a severe (DS{>=}65%) infarct-related stenosis, while the echocardiographic detection of ischaemia was not influenced by stenosis severity (sensitivity of 73% in both subgroups). This scintigraphic underestimation of jeopardized myocardium was mainly related to a severely impaired myocardial perfusion under baseline conditions, as was evidenced by a significantly more severe rest perfusion score in the infarct region in patients with a severe stenosis as compared to those with a moderate stenosis, while infarct size on echocardiography was similar for both subgroups. It may be concluded that early after an acute myocardial infarction, adenosine {sup 99m}Tc-sestamibi SPET may underestimate reperfused but still jeopardized myocardium, particularly in patients with a severe infarct-related stenosis. In these patients the evaluation of the ischaemic burden on rest-stress scintigraphy is hampered by the presence of a severely impaired myocardial perfusion in resting conditions. (orig

  12. Familial Transient Global Amnesia

    Directory of Open Access Journals (Sweden)

    R.Rhys Davies

    2012-12-01

    Full Text Available Following an episode of typical transient global amnesia (TGA, a female patient reported similar clinical attacks in 2 maternal aunts. Prior reports of familial TGA are few, and no previous account of affected relatives more distant than siblings or parents was discovered in a literature survey. The aetiology of familial TGA is unknown. A pathophysiological mechanism akin to that in migraine attacks, comorbidity reported in a number of the examples of familial TGA, is one possibility. The study of familial TGA cases might facilitate the understanding of TGA aetiology.

  13. Thermal transient anemometer

    Science.gov (United States)

    Bailey, James L.; Vresk, Josip

    1989-01-01

    A thermal transient anemometer having a thermocouple probe which is utilized to measure the change in temperature over a period of time to provide a measure of fluid flow velocity. The thermocouple probe is located in the fluid flow path and pulsed to heat or cool the probe. The cooling of the heated probe or the heating of the cooled probe from the fluid flow over a period of time is measured to determine the fluid flow velocity. The probe is desired to be locally heated near the tip to increase the efficiency of devices incorporating the probe.

  14. Mild episodes of tourniquet-induced forearm ischaemia-reperfusion injury results in leukocyte activation and changes in inflammatory and coagulation markers

    Directory of Open Access Journals (Sweden)

    Bastawrous Salah S

    2007-05-01

    Full Text Available Abstract Background Monocytes and neutrophils are examples of phagocytic leukocytes, with neutrophils being considered as the 'chief' phagocytic leukocyte. Both monocytes and neutrophils have been implicated to play a key role in the development of ischaemia-reperfusion injury, where they are intrinsically involved in leukocyte-endothelial cell interactions. In this pilot study we hypothesised that mild episodes of tourniquet induced forearm ischaemia-reperfusion injury results in leukocyte activation and changes in inflammatory and coagulation markers. Methods Ten healthy human volunteers were recruited after informed consent. None had any history of cardiovascular disease with each subject volunteer participating in the study for a 24 hour period. Six venous blood samples were collected from each subject volunteer at baseline, 10 minutes ischaemia, 5, 15, 30, 60 minutes and 24 hours reperfusion, by means of a cannula from the ante-cubital fossa. Monocyte and neutrophil leukocyte sub-populations were isolated by density gradient centrifugation techniques. Leukocyte trapping was investigated by measuring the concentration of leukocytes in venous blood leaving the arm. The cell surface expression of CD62L (L-selectin, CD11b and the intracellular production of hydrogen peroxide (H2O2 were measured via flow cytometry. C-reactive protein (CRP was measured using a clinical chemistry analyser. Plasma concentrations of D-dimer and von Willebrand factor (vWF were measured using enzyme-linked fluorescent assays (ELFA. Results During ischaemia-reperfusion injury, there was a decrease in CD62L and an increase in CD11b cell surface expression for both monocytes and neutrophils, with changes in the measured parameters reaching statistical significance (p =2O2 production by leukocyte sub-populations, which was measured as a marker of leukocyte activation. Intracellular production of H2O2 in monocytes during ischaemia-reperfusion injury reached statistical

  15. Thallium-201 myocardial imaging in acute-myocardial infarction

    International Nuclear Information System (INIS)

    Wackers, F.J.Th.; Lie, K.I.; Sokole, E.B.; Wellens, H.J.J.; Samson, G.; Schoot, J.B. van der

    1980-01-01

    Thallium-201 scintigraphy has proven to be an early and highly sensitive technique to detect myocardial perfusion abnormalities in patients with acute myocardial infarction. During the early phase of acute myocardial infarction, patients may be hemodynamically and electrically unstable. Therefore, scintigraphy is performed preferably at the bed side in the Coronary Care Unit using a mobile gamma camera. Additionally, in order to shorten imaging time in these often critically ill patients, the authors recommend injecting no less than 2 mCi of 201 Tl. Using this dosage, the imaging time per view will be approximately five minutes. Routinely, three views are taken: the first view is a supine 45 0 left-anterior-oblique view, followed by a supine anterior view and finally a left-lateral view, the latter with the patient turned on the right side. (Auth.)

  16. Heart rate is a prognostic risk factor for myocardial infarction: a post hoc analysis in the PERFORM (Prevention of cerebrovascular and cardiovascular Events of ischemic origin with teRutroban in patients with a history oF ischemic strOke or tRansient ischeMic attack) study population.

    Science.gov (United States)

    Fox, Kim; Bousser, Marie-Germaine; Amarenco, Pierre; Chamorro, Angel; Fisher, Marc; Ford, Ian; Hennerici, Michael G; Mattle, Heinrich P; Rothwell, Peter M

    2013-10-09

    Elevated resting heart rate is known to be detrimental to morbidity and mortality in cardiovascular disease, though its effect in patients with ischemic stroke is unclear. We analyzed the effect of baseline resting heart rate on myocardial infarction (MI) in patients with a recent noncardioembolic cerebral ischemic event participating in PERFORM. We compared fatal or nonfatal MI using adjusted Cox proportional hazards models for PERFORM patients with baseline heart rate heart rate was analyzed as a continuous variable. Other cerebrovascular and cardiovascular outcomes were also explored. Heart rate ≥70 bpm was associated with increased relative risk for fatal or nonfatal MI (HR 1.32, 95% CI 1.03-1.69, P=0.029). For every 5-bpm increase in heart rate, there was an increase in relative risk for fatal and nonfatal MI (11.3%, P=0.0002). Heart rate ≥70 bpm was also associated with increased relative risk for a composite of fatal or nonfatal ischemic stroke, fatal or nonfatal MI, or other vascular death (excluding hemorrhagic death) (Pheart rate, there were increases in relative risk for fatal or nonfatal ischemic stroke, fatal or nonfatal MI, or other vascular death (4.7%, Pheart rate ≥70 bpm places patients with a noncardioembolic cerebral ischemic event at increased risk for MI. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  17. Glaucocalyxin A Ameliorates Myocardial Ischemia-Reperfusion Injury in Mice by Suppression of Microvascular Thrombosis

    Science.gov (United States)

    Liu, Xiaohui; Xu, Dongzhou; Wang, Yuxin; Chen, Ting; Wang, Qi; Zhang, Jian; You, Tao; Zhu, Li

    2016-01-01

    Background The aim of this study was to evaluate the cardio-protective roles of glaucocalyxin A (GLA) in myocardial ischemia-reperfusion injury and to explore the underlying mechanism. Material/Methods Myocardial ischemia-reperfusion in wild-type C57BL/6J mice was induced by transient ligation of the left anterior descending artery. GLA or vehicle (solvent) was administrated intraperitoneally to the mice before reperfusion started. After 24 h of myocardial reperfusion, ischemic size was revealed by Evans blue/TTC staining. Cardiac function was evaluated by echocardiography and microvascular thrombosis was assessed by immunofluorescence staining of affected heart tissue. We also measured the phosphorylation of AKT, ERK, P-GSK-3β, and cleaved caspase 3 in the myocardium. Results Compared to the solvent-treated control group, GLA administration significantly reduced infarct size (GLA 13.85±2.08% vs. Control 18.95±0.97%, pthrombosis (Pthrombosis. PMID:27716735

  18. Value of planar 201Tl imaging in risk stratification of patients recovering from acute myocardial infarction

    International Nuclear Information System (INIS)

    Gibson, R.S.; Watson, D.D.

    1991-01-01

    Although exercise ECG testing has been shown to have important prognostic value after acute myocardial infarction, exercise 201Tl scintigraphy offers several potential advantages, including: (1) increased sensitivity for detecting residual myocardial ischemia; (2) the ability to localize ischemia to a specific area or areas subtended by a specific coronary artery; (3) the ability to identify exercise-induced left ventricular dysfunction, which is manifested by increased lung uptake or transient left ventricular dilation; and (4) more reliable risk stratification of individual patients. The more optimal prognostic efficiency of 201Tl scintigraphy partially results from the fact that the error rate in falsely classifying patients as low risk is significantly smaller with 201Tl scintigraphy than with stress ECG. Because of these substantial advantages, there seems to be adequate rationale for recommending exercise perfusion imaging rather than exercise ECG alone as the preferred method for evaluating mortality and morbidity risks after acute myocardial infarction

  19. Effects of coronary artery bypass surgery on regions showing persistent defects in thallium myocardial images

    International Nuclear Information System (INIS)

    Konishi, Yutaka; Ban, Toshihiko; Okamoto, Yoshifumi

    1989-01-01

    The indications for revascularization surgery and its effects on myocardial regions showing persistent defects in thallium myocardial images are controversial. The effects of aortocoronary bypass surgery on myocardial perfusion and wall motion in the regions with persistent defects were evaluated in 47 patients with thallium-201 single photon emission computed tomography and left ventriculography. In areas showing persistent thallium defects preoperatively the rate of improvement of perfusion was only 24% by postoperative thallium imaging, and 57% by wall motion analysis. These results were significantly inferior to those of regions with transient defects, which were 84% and 82%, respectively. A persistent defect may not be a definitive marker of a non-viable scar, but the results of surgery on such regions were unsatisfactory. It is concluded, therefore, that revascuralization surgery in regions with persistent defects is not always recommended and that the indications for surgery should be individually determined with operative risk balanced against benefits. (author)

  20. Angiographic assessment of reperfusion in acute myocardial infarction by myocardial blush grade

    NARCIS (Netherlands)

    Henriques, JPS; Zijlstra, F; van 't Hof, AWJ; de Boer, MJ; Gosselink, M; Hoorntje, JCA; Suryapranata, H; Dambrink, Jan Hendrik Everwijn

    2003-01-01

    Background-Angiographic successful reperfusion in acute myocardial infarction has been defined as TIMI 3 flow. However, TIMI 3 flow does not always result in effective myocardial reperfusion. Myocardial blush grade (MBG) is an angiographic measure of myocardial perfusion. We hypothesized that

  1. Angiographic assessment of reperfusion in acute myocardial infarction by myocardial blush grade

    NARCIS (Netherlands)

    Henriques, Jose P. S.; Zijlstra, Felix; van 't Hof, Arnoud W. J.; de Boer, Menko-Jan; Dambrink, Jan-Henk E.; Gosselink, Marcel; Hoorntje, Jan C. A.; Suryapranata, Harry

    2003-01-01

    Angiographic successful reperfusion in acute myocardial infarction has been defined as TIMI 3 flow. However, TIMI 3 flow does not always result in effective myocardial reperfusion. Myocardial blush grade (MBG) is an angiographic measure of myocardial perfusion. We hypothesized that optimal

  2. COLIN trial: Value of colchicine in the treatment of patients with acute myocardial infarction and inflammatory response.

    Science.gov (United States)

    Akodad, Mariama; Lattuca, Benoît; Nagot, Nicolas; Georgescu, Vera; Buisson, Mathilde; Cristol, Jean-Paul; Leclercq, Florence; Macia, Jean-Christophe; Gervasoni, Richard; Cung, Thien-Tri; Cade, Stéphane; Cransac, Frédéric; Labour, Jessica; Dupuy, Anne-Marie; Roubille, François

    Inflammation is involved during acute myocardial infarction, and could be an interesting target to prevent ischaemia-reperfusion injuries. Colchicine, known for its pleiotropic anti-inflammatory effects, could decrease systemic inflammation in this context. To evaluate the impact of colchicine on inflammation in patients admitted for ST-segment elevation myocardial infarction (STEMI). All patients admitted for STEMI with one of the main coronary arteries occluded, and successfully treated with percutaneous coronary intervention, were included consecutively. Patients were randomized to receive either 1mg colchicine once daily for 1 month plus optimal medical treatment or optimal medical treatment only. C-reactive protein (CRP) was assessed at admission and daily until hospital discharge. The primary endpoint was CRP peak value during the index hospitalization. Forty-four patients were included: 23 were treated with colchicine; 21 received conventional treatment only. At baseline, both groups were well balanced regarding age, sex, risk factors, thrombolysis in myocardial infarction flow and reperfusion delay. The culprit artery was more often the left anterior descending artery in the colchicine group (P=0.07), reflecting a more severe group. There was no significant difference in mean CRP peak value between the colchicine and control groups (29.03mg/L vs 21.86mg/L, respectively; P=0.36), even after adjustment for type of culprit artery (26.99 vs 24.99mg/L, respectively; P=0.79). In our study, the effect of colchicine on inflammation in the context of STEMI could not be demonstrated. Further larger studies may clarify the impact of colchicine in acute myocardial infarction. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  3. Transient regional osteoporosis

    Directory of Open Access Journals (Sweden)

    F. Trotta

    2011-09-01

    Full Text Available Transient osteoporosis of the hip and regional migratory osteoporosis are uncommon and probably underdiagnosed bone diseases characterized by pain and functional limitation mainly affecting weight-bearing joints of the lower limbs. These conditions are usually self-limiting and symptoms tend to abate within a few months without sequelae. Routine laboratory investigations are unremarkable. Middle aged men and women during the last months of pregnancy or in the immediate post-partum period are principally affected. Osteopenia with preservation of articular space and transitory edema of the bone marrow provided by magnetic resonance imaging are common to these two conditions, so they are also known by the term regional transitory osteoporosis. The appearance of bone marrow edema is not specific to regional transitory osteoporosis but can be observed in several diseases, i.e. trauma, reflex sympathetic dystrophy, avascular osteonecrosis, infections, tumors from which it must be differentiated. The etiology of this condition is unknown. Pathogenesis is still debated in particular the relationship with reflex sympathetic dystrophy, with which regional transitory osteoporosis is often identified. The purpose of the present review is to remark on the relationship between transient osteoporosis of the hip and regional migratory osteoporosis with particular attention to the bone marrow edema pattern and relative differential diagnosis.

  4. Transient congenital hypothyroidism

    Directory of Open Access Journals (Sweden)

    Nisha Bhavani

    2011-01-01

    Full Text Available Transient thyroid function abnormalities in the new born which revert back to normal after varying periods of time are mostly identified in the neonatal screening tests for thyroid and are becoming more common because of the survival of many more premature infants. It can be due to factors primarily affecting the thyroid-like iodine deficiency or excess, maternal thyroid-stimulating hormone receptor (TSHR antibodies, maternal use of antithyroid drugs, DUOX 2 (dual oxidase 2 mutations, and prematurity or those that affect the pituitary-like untreated maternal hyperthyroidism, prematurity, and drugs. Most of these require only observation, whereas some, such as those due to maternal TSHR antibodies may last for upto three-to-six months and may necessitate treatment. Isolated hyperthyrotropinemia (normal Tetraiodothyronine (T4 and high Thyroid Stimulating hormone (TSH may persist as subclinical hypothyroidism in childhood. Transient hypothyroxinemia (low T4 and normal TSH is very common in premature babies. The recognition of these conditions will obviate the risks associated with unnecessary thyroxine supplementation in childhood and parental concerns of a life long illness in their offspring.

  5. Cryoinjury : a model of myocardial regeneration

    NARCIS (Netherlands)

    van Amerongen, Machteld J.; Hamsen, Martin C.; Petersen, Arien H.; Popa, Eliane R.; van Luyn, Marja J. A.

    2008-01-01

    Introduction: Although traditionally adult cardiomyocytes are thought to be unable to divide, recent observations provide evidence for cardiomyocyte proliferation after myocardial injury. Myocardial cryoinjury has been shown to be followed by neovascularization. We hypothesize that, in addition to

  6. How reliable is myocardial imaging in the diagnosis of acute myocardial infarction

    International Nuclear Information System (INIS)

    Willerson, J.T.

    1983-01-01

    Myocardial scintigraphic techniques available presently allow a sensitive and relatively specific diagnosis of acute myocardial infarction when they are used correctly, although every technique has definite limitations. Small myocardial infarcts (less than 3 gm.) may be missed, and there are temporal limitations in the usefulness of the scintigraphic techniques. The development of tomographic methodology that may be used with single-photon radionuclide emitters (including technetium and 201 Tl will allow the detection of relatively small abnormalities in myocardial perfusion and regions of myocardial infarction and will help to provide a more objective interpretation of the myocardial scintigrams. The use of overlay techniques allowing simultaneous assessment of myocardial perfusion, infarct-avid imaging, and radionuclide ventriculograms will provide insight into the relevant aspects of the extent of myocardial damage, the relationship of damage to myocardial perfusion, and the functional impact of myocardial infarction on ventricular performance

  7. Acupuncture elicits neuroprotective effect by inhibiting NAPDH oxidase-mediated reactive oxygen species production in cerebral ischaemia.

    Science.gov (United States)

    Shi, Guang-Xia; Wang, Xue-Rui; Yan, Chao-Qun; He, Tian; Yang, Jing-Wen; Zeng, Xiang-Hong; Xu, Qian; Zhu, Wen; Du, Si-Qi; Liu, Cun-Zhi

    2015-12-10

    In the current study, we aimed to investigate whether NADPH oxidase, a major ROS-producing enzyme, was involved in the antioxidant effect of acupuncture on cognitive impairment after cerebral ischaemia. The cognitive function, infract size, neuron cell loss, level of superoxide anion and expression of NADPH oxidase subunit in hippocampus of two-vessel occlusion (2VO) rats were determined after 2-week acupuncture. Furthermore, the cognitive function and production of O2(-) were determined in the presence and absence of NADPH oxidase agonist (TBCA) and antagonist (Apocynin). The effect of acupuncture on cognitive function after cerebral ischaemia in gp91phox-KO mice was evaluated by Morris water maze. Acupuncture reduced infarct size, attenuated overproduction of O2(-), and reversed consequential cognitive impairment and neuron cell loss in 2VO rats. The elevations of gp91phox and p47phox after 2VO were significantly decreased after acupuncture treatment. However, no differences of gp91phox mRNA were found among any experimental groups. Furthermore, these beneficial effects were reversed by TBCA, whereas apocynin mimicked the effect of acupuncture by improving cognitive function and decreasing O2(-) generation. Acupuncture failed to improve the memory impairment in gp91phox KO mice. Full function of the NADPH oxidase enzyme plays an important role in neuroprotective effects against cognitive impairment via inhibition of NAPDH oxidase-mediated oxidative stress.

  8. Novel method to study pericyte contractility and responses to ischaemia in vitro using electrical impedance.

    Science.gov (United States)

    Neuhaus, Ain A; Couch, Yvonne; Sutherland, Brad A; Buchan, Alastair M

    2017-06-01

    Pericytes are contractile vascular mural cells overlying capillary endothelium, and they have been implicated in a variety of functions including regulation of cerebral blood flow. Recent work has suggested that both in vivo and ex vivo, ischaemia causes pericytes to constrict and die, which has implications for microvascular reperfusion. Assessing pericyte contractility in tissue slices and in vivo is technically challenging, while in vitro techniques remain unreliable. Here, we used isolated cultures of human brain vascular pericytes to examine their contractile potential in vitro using the iCelligence electrical impedance system. Contraction was induced using the vasoactive peptide endothelin-1, and relaxation was demonstrated using adenosine and sodium nitroprusside. Endothelin-1 treatment also resulted in increased proliferation, which we were able to monitor in the same cell population from which we recorded contractile responses. Finally, the observation of pericyte contraction in stroke was reproduced using chemical ischaemia, which caused a profound and irreversible contraction clearly preceding cell death. These data demonstrate that isolated pericytes retain a contractile phenotype in vitro, and that it is possible to quantify this contraction using real-time electrical impedance recordings, providing a significant new platform for assessing the effects of vasoactive and vasculoprotective compounds on pericyte contractility.

  9. Angiopoietin-2 impairs collateral artery growth associated with the suppression of the infiltration of macrophages in mouse hindlimb ischaemia

    Directory of Open Access Journals (Sweden)

    Xiaoyong Tan

    2016-10-01

    Full Text Available Abstract Background Angiopoietin-2 (Ang-2, a ligand of the Tie-2 receptor, plays an important role in maintaining endothelial cells and in destabilizing blood vessels. Collateral artery growth (arteriogenesis is a key adaptive response to arterial occlusion. It is unknown whether the destabilization of blood vessels by Ang-2 can affect arteriogenesis and modulate mononuclear cell function. This study aimed to investigate the effects of Ang-2 on collateral artery growth. Methods Hindlimb ischaemia model was produced in C57BL/6 mice by femoral artery ligation. Blood flow perfusion was measured using a laser Doppler perfusion imager quantitative RT-PCR analysis was applied to identify the level of angiogenic factors. Results After the induction of hindlimb ischaemia, blood flow recovery was impaired in mice treated with recombinant Ang-2 protein; this was accompanied by a reduction of peri-collateral macrophage infiltration. In addition, quantitative RT-PCR analysis revealed that Ang-2 treatment decreased monocyte chemotactic protein-1 (MCP-1, platelet-derived growth factor-BB (PDGF-BB mRNA levels in ischaemic adductor muscles. Ang-2 can lead to macrophage M1/M2 polarization shift inhibition in the ischaemic muscles. Furthermore, Ang-2 reduced the in vitro inflammatory response in macrophages and vascular cells involved in arteriogenesis. Conclusions Our results demonstrate that Ang-2 is essential for efficient arteriogenesis, which controls macrophage infiltration.

  10. Myocardial infarction after near drowning.

    Science.gov (United States)

    Chen, Li-Bang; Lai, Yen-Chun; Chen, Chang-Chih; Chang, Wen-Han; Su, Yu-Jang

    2008-06-01

    During summer, near drowning is a common accident in Taiwan. It may lead to multiple organ damages in cases where severe hypothermia and hypoxemia occur. We present a case of myocardial infarction after near drowning. The patient was sent to our ED by the emergency medical services called by the witness. On arrival to our ED, hypothermia and hypoxemia overcame him. Endotracheal intubation and warm intravenous fluid were applied at once owing to drowsy consciousness, respiratory distress, and hypothermia. Electrocardiogram showed diffuse ST-segment elevation over the precordial leads V2-V6. The initial level of cardiac enzymes was within normal limit but elevated in troponin I on the second day after hospitalization. We presumed that the possibility of myocardial infarction resulted from near drowning-related hypoxemia. To our knowledge, this is the first case describing myocardial injury with electrocardiogram changes after near drowning.

  11. Myocardial perfusion modeling using MRI

    DEFF Research Database (Denmark)

    Larsson, H B; Fritz-Hansen, T; Rostrup, Egill

    1996-01-01

    In the present study, it is shown that it is possible to quantify myocardial perfusion using magnetic resonance imaging in combination with gadolinium diethylenetriaminopentaacetic acid (Gd-DTPA). Previously, a simple model and method for measuring myocardial perfusion using an inversion recovery...... of Gd-DTPA (lambda), the vascular blood volume (Vb), and the time delay through the coronary arteries (delta T). The model was evaluated by computer simulation and used on experimental results from seven healthy subjects. The results in the healthy volunteers for a region of interest placed...... in the anterior myocardial wall were (mean +/- SD) Ki = 54 +/- 10 ml/100 g/min, lambda = 30 +/- 3 ml/100 g, Vb = 9 +/- 2 ml/100 g, delta T = 3.2 +/- 1.1 s. These results are in good agreement with similar results obtained by other methods....

  12. Dynamic CT myocardial perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncological and Pathological Sciences, University of Rome “Sapienza”, Latina (Italy); Eid, Marwen [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States); Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul (Korea, Republic of); Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Mangold, Stefanie [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Tuebingen (Germany); and others

    2016-10-15

    Highlights: • CT myocardial perfusion provides functional assessment of the myocardium. • CCTA is limited in determining the hemodynamic significance of coronary stenosis. • CT-MPI can accurately detect hemodynamically significant coronary artery stenosis. - Abstract: Non-invasive cardiac imaging has rapidly evolved during the last decade due to advancements in CT based technologies. Coronary CT angiography has been shown to reliably assess coronary anatomy and detect high risk coronary artery disease. However, this technique is limited to anatomical assessment, thus non-invasive techniques for functional assessment of the heart are necessary. CT myocardial perfusion is a new CT based technique that provides functional assessment of the myocardium and allows for a comprehensive assessment of coronary artery disease with a single modality when combined with CTA. This review aims to discuss dynamic CT myocardial perfusion as a new technique in the assessment of CAD.

  13. Inflammatory Response During Myocardial Infarction.

    Science.gov (United States)

    Oliveira, Joaquim B; Soares, Alexandre A S M; Sposito, Andrei C

    2018-01-01

    The occlusion of a coronary artery by a thrombus generated on a ruptured atherosclerotic plaque has been pursued in the last decades as a determining event for the clinical outcome after myocardial infarction (MI). Yet, MI causes a cell death wave front, which triggers an inflammatory response to clear cellular debris, and which in excess can double the myocardial lesion and influence the clinical prognosis in the short and long term. Accordingly, proper, timely regulated inflammatory response has now been considered a second pivotal player in cardiac recovery after MI justifying the search for pharmacological strategies to modulate inflammatory effectors. This chapter reviews the key events and the main effectors of inflammation after myocardial ischemic insult, as well as the contribution of this phenomenon to the progression of atherosclerosis. © 2018 Elsevier Inc. All rights reserved.

  14. Transient elevation of ST-segment due to pneumothorax and pneumopericardium

    Directory of Open Access Journals (Sweden)

    Rodrigo Martins Brandão

    2013-03-01

    Full Text Available ST-segment elevation, observed in the critically ill patients, almost always raises the suspicion of ischemic heart disease. However, nonischemic myocardial and non-myocardial problems in these patients may also lead to ST-segment elevation. Pneumothorax and pneumopericardium have been rarely reported as a cause of transient ST-segment elevation. The authors report the case of a patient admitted to the emergency care unit because of a respiratory failure requiring mechanical ventilatory support. As the patient showed signs of clinical deterioration, a pneumothorax was clinically diagnosed. Chest radiography after thorax drainage also disclosed a pneumopericardium. The 12-lead electrocardiogram recorded before the thoracic drainage revealed an ST-segment elevation, which normalized after the surgical procedure. Ischemic myocardial biomarkers were negative. The authors call attention to the right-sided pneumothorax associated with pneumopericardium as an unusual cause of ST-segment elevation.

  15. Distinct myocardial mechanisms underlie cardiac dysfunction in endotoxemic male and female mice

    OpenAIRE

    Hobai, Ion A.; Aziz, Kanwal; Buys, Emmanuel S.; Brouckaert, Peter; Siwik, Deborah A.; Colucci., Wilson S.

    2016-01-01

    In male mice, Sepsis-Induced Cardiomyopathy develops as a result of dysregulation of myocardial calcium (Ca2+) handling, leading to depressed cellular Ca2+ transients (ΔCai). ΔCai depression is partially due to inhibition of sarcoplasmic reticulum Ca2+ ATP-ase (SERCA) via oxidative modifications, which are partially opposed by cGMP generated by the enzyme soluble guanylyl cyclase (sGC). Whether similar mechanisms underlie Sepsis-Induced Cardiomyopathy in female mice is unknown.

  16. Morphological aspects of myocardial bridges.

    Science.gov (United States)

    Lujinović, Almira; Kulenović, Amela; Kapur, Eldan; Gojak, Refet

    2013-11-01

    Although some myocardial bridges can be asymptomatic, their presence often causes coronary disease either through direct compression of the "tunnel" segment or through stimulation and accelerated development of atherosclerosis in the segment proximally to the myocardial bridge. The studied material contained 30 human hearts received from the Department of Anatomy. The hearts were preserved 3 to 5 days in 10% formalin solution. Thereafter, the fatty tissue was removed and arterial blood vessels prepared by careful dissection with special reference to the presence of the myocardial bridges. Length and thickness of the bridges were measured by the precise electronic caliper. The angle between the myocardial bridge fibre axis and other axis of the crossed blood vessel was measured by a goniometer. The presence of the bridges was confirmed in 53.33% of the researched material, most frequently (43.33%) above the anterior interventricular branch. The mean length of the bridges was 14.64 ± 9.03 mm and the mean thickness was 1.23 ± 1.32 mm. Myocardial bridge fibres pass over the descending blood vessel at the angle of 10-90 degrees. The results obtained on a limited sample suggest that the muscular index of myocardial bridge is the highest for bridges located on RIA, but that the difference is not significant in relation to bridges located on other branches. The results obtained suggest that bridges located on other branches, not only those on RIA, could have a great contractive power and, consequently, a great compressive force, which would be exerted on the wall of a crossed blood vessel.

  17. Morphological aspects of myocardial bridges

    Directory of Open Access Journals (Sweden)

    Almira Lujinović

    2013-11-01

    Full Text Available Although some myocardial bridges can be asymptomatic, their presence often causes coronary disease either through direct compression of the “tunnel” segment or through stimulation and accelerated development of atherosclerosis in the segment proximally to the myocardial bridge. The studied material contained 30 human hearts received from the Department of Anatomy. The hearts were preserved 3 to 5 days in 10% formalin solution. Thereafter, the fatty tissue was removed and arterial blood vessels prepared by careful dissection with special reference to the presence of the myocardial bridges. Length and thickness of the bridges were measured by the precise electronic caliper. The angle between the myocardial bridge fibre axis and other axis of the crossed blood vessel was measured by a goniometer. The presence of the bridges was confirmed in 53.33% of the researched material, most frequently (43.33% above the anterior interventricular branch. The mean length of the bridges was 14.64±9.03 mm and the mean thickness was 1.23±1.32 mm. Myocardial bridge fibres pass over the descending blood vessel at the angle of 10-90 degrees. The results obtained on a limited sample suggest that the muscular index of myocardial bridge is the highest for bridges located on RIA, but that the difference is not significant in relation to bridges located on other branches. The results obtained suggest that bridges located on other branches, not only those on RIA, could have a great contractive power and, consequently, a great compressive force, which would be exerted on the wall of a crossed blood vessel.

  18. Transient osteoporosis of the hip

    International Nuclear Information System (INIS)

    McWalter, Patricia; Hassan Ahmed

    2007-01-01

    Transient osteoporosis of the hip is an uncommon cause of hip pain, mostly affecting healthy middle-aged men and also women in the third trimester of pregnancy. We present a case of transient osteoporosis of the hip in a 33-year-old non-pregnant female patient. This case highlights the importance of considering a diagnosis of transient osteoporosis of the hip in patients who present with hip pain. (author)

  19. Transient Go: A Mobile App for Transient Astronomy Outreach

    Science.gov (United States)

    Crichton, D.; Mahabal, A.; Djorgovski, S. G.; Drake, A.; Early, J.; Ivezic, Z.; Jacoby, S.; Kanbur, S.

    2016-12-01

    Augmented Reality (AR) is set to revolutionize human interaction with the real world as demonstrated by the phenomenal success of `Pokemon Go'. That very technology can be used to rekindle the interest in science at the school level. We are in the process of developing a prototype app based on sky maps that will use AR to introduce different classes of astronomical transients to students as they are discovered i.e. in real-time. This will involve transient streams from surveys such as the Catalina Real-time Transient Survey (CRTS) today and the Large Synoptic Survey Telescope (LSST) in the near future. The transient streams will be combined with archival and latest image cut-outs and other auxiliary data as well as historical and statistical perspectives on each of the transient types being served. Such an app could easily be adapted to work with various NASA missions and NSF projects to enrich the student experience.

  20. Both autologous bone marrow mononuclear cell and peripheral blood progenitor cell therapies similarly improve ischaemia in patients with diabetic foot in comparison with control treatment

    Czech Academy of Sciences Publication Activity Database

    Dubský, M.; Jirkovská, A.; Bém, R.; Fejfarová, V.; Pagacová, L.; Sixta, B.; Varga, M.; Langkramer, S.; Syková, Eva; Jude, E. B.

    2013-01-01

    Roč. 29, č. 5 (2013), s. 369-376 ISSN 1520-7552 R&D Projects: GA ČR GAP304/11/0653 Grant - others:GA MŠk(CZ) GAUK 362311 Institutional support: RVO:68378041 Keywords : stem cell therapy * diabetic foot * critical limb ischaemia Subject RIV: FP - Other Medical Disciplines Impact factor: 2.968, year: 2012

  1. Augmented hyperaemia and reduced tissue injury in response to ischaemia in subjects with the 34C > T variant of the AMPD1 gene.

    NARCIS (Netherlands)

    Riksen, N.P.; Franke, B.; Oyen, W.J.G.; Borm, G.F.; Broek, P. van den; Boerman, O.C.; Smits, P.; Rongen, G.A.

    2007-01-01

    AIMS: In patients with coronary artery disease, the 34C > T variant of the adenosine mono-phosphate deaminase gene (AMPD1), encoding a dysfunctional protein, predicts improved survival. We hypothesized that in subjects with this variant allele, ischaemia-induced intracellular adenosine formation

  2. Aniracetam, a pyrrolidinone-type cognition enhancer, attenuates the hydroxyl free radical formation in the brain of mice with brain ischaemia.

    Science.gov (United States)

    Himori, N; Suzuki, T; Ueno, K

    1995-03-01

    We demonstrate here that aniracetam has the ability to block the formation of cytotoxic hydroxyl radicals (.OH) during ischaemia-reperfusion of mouse brain. The fact that brain ischeamia for 40 min followed by reperfusion increased .OH was evidenced by detection of a peaked increase at 20 min after an ischaemic insult in the formation of 2,3-dihydroxybenzoate (DHBA) from salicylate in cerebroventricular perfusate, a means of monitoring .OH formation. A clearcut increase in dopamine was also observed during and after brain ischaemia. The ischaemia-reperfusion mice given aniracetam at an intraperitoneal dose of 30 or 100 mg kg-1 showed a smaller increase in the formation of DHBA than those given the vehicle only. Aniracetam at 100 mg kg-1 significantly suppressed the formation of DHBA by approximately 80%, becoming evident at 20 min after reperfusion and thereafter. Protection against death in mice insulted with a 40-min brain ischaemia (3/13 vs 13/25) was observed following 100 mg kg-1 aniracetam. The increase in the dopamine levels was substantially reduced following aniracetam treatment and the reduction became significant at 20 min after reperfusion and thereafter in parallel with attenuation by aniracetam of DHBA formation. This finding suggests that the inhibitory activity of aniracetam in attenuating the hydroxyl free-radical formation in ischaemic mice is probably due, at least in part, to its palliative action on the dopaminergic neurons.

  3. Myocardial bridging causing ischemia and recurrent chest pain: a case report

    Directory of Open Access Journals (Sweden)

    Abdou Mohamed

    2011-07-01

    Full Text Available Abstract Background Myocardial bridging is present when a segment of a major epicardial coronary artery runs intramurally through the myocardium. It usually has a benign prognosis, but in some cases myocardial ischemia, infarction and sudden cardiac death have been reported. We are here reporting a case of myocardial bridging which was complicated with recurrent chest pain and transient ST-segment elevation during exercise treadmill test. Case presentation A 40 year-old-man presented with recurrent retrosternal chest pain of 2 months duration. He had history of smoking and was obese, otherwise no physical abnormalities were detected by examination. Electrocardiogram and blood tests were normal apart from impaired glucose tolerance with elevated triglycerides and decreased level of high density lipoprotein cholesterol. While doing exercise treadmill test, the patient developed chest pain and significant ST-segment elevation in almost all precordial leads that persisted for about 15 minutes through recovery. We decided to admit the patient to the coronary care unit for further management and to perform coronary angiogram. Myocardial bridging was observed in the mid segment of the left anterior descending coronary artery. Medical treatment was decided. At one year follow up, our patient was healthy and had no cardiac complaints. In conclusion, myocardial bridging may predispose to coronary vasospasm that may leads to ischemic complications.

  4. Dosimetry in myocardial perfusion imaging

    International Nuclear Information System (INIS)

    Toledo, Janine M.; Trindade, Bruno; Ribeiro, Tarcisio P.C.

    2011-01-01

    This paper conducts a dosimetric investigation on the myocardial perfusion image protocol, together with a literature reviewing, motivated by the significant statistic increasing on mortality, morbidity and disability associated with cardiovascular disease, surpassing infectious diseases. Nuclear Cardiology plays a role n the diagnostic functional evaluation of the heart and in the prognostic of patients with suspected or known cardiac ischemia. In the context of unstable myocardial ischemic syndrome, myocardial perfusion scintigraphy is a non-invasive procedure performed by administering a radiopharmaceutical targeted to the heart. As tool for this study are that the images obtained by thoracic angiotomography and abdominal aorta as a anatomic and functional information for model reproduction in SISCODES - System of Codes for Absorbed Dose Calculations based on Stochastic Methods. Data were manipulated in order to create a voxel computational model of the heart to be running in MCNP - Monte Carlo Neutron Particle Code. . It was assumed a homogeneous distribution of Tl-201 in cardiac muscle. Simulations of the transport of particles through the voxel and the interaction with the heart tissue were performed. As a result, the isodose curves in the heart model are displayed as well as the dose versus volume histogram of the heart muscle. We conclude that the present computational tools can generate doses distributed in myocardial perfusion. (author)

  5. Perceived stress in myocardial infarction

    NARCIS (Netherlands)

    Arnold, Suzanne V.; Smolderen, K.G.E.; Buchanan, Donna M.; Li, Yan; Spertus, John A.

    2012-01-01

    Objectives This study sought to determine the association of chronic stress with long-term adverse outcomes after acute myocardial infarction (AMI).BackgroundChronic stress has been shown to be associated with the development of cardiovascular disease and, in the case of particular types of stress

  6. The Orchestra of Myocardial Regeneration

    NARCIS (Netherlands)

    Siddiqi, S.

    2014-01-01

    A glimpse on previous and current literature ignites the recognition of the luxurious era that cardiac science has reached. In particular, the past fifteen years have provided tremendous advancements in the field of myocardial biology with the characterization of cardiac stem cells, reprogramming of

  7. Myocardial perfusion at fatal infarction

    DEFF Research Database (Denmark)

    Hvid-Jacobsen, K; Møller, J T; Kjøller, E

    1992-01-01

    In a consecutive study of myocardial scintigraphy in acute ischemic syndrome, four patients had 99mTc-hexamibi injected intravenously before they developed fatal cardiogenic shock. Planar scintigraphy was performed after death. Slices of the hearts after autopsy were analyzed for scintigraphic...

  8. Spousal Adjustment to Myocardial Infarction.

    Science.gov (United States)

    Ziglar, Elisa J.

    This paper reviews the literature on the stresses and coping strategies of spouses of patients with myocardial infarction (MI). It attempts to identify specific problem areas of adjustment for the spouse and to explore the effects of spousal adjustment on patient recovery. Chapter one provides an overview of the importance in examining the…

  9. Pregnancy-related myocardial infarction

    NARCIS (Netherlands)

    Lameijer, H.; Lont, M. C.; Buter, H.; van Boven, A. J.; Boonstra, P. W.; Pieper, P. G.

    Introduction The risk of acute myocardial infarction in young women is low, but increases during pregnancy due to the physiological changes in pregnancy, including hypercoagulability. Ischaemic heart disease during pregnancy is not only associated with increased maternal morbidity and mortality, but

  10. Neonatal Myocardial Infarction or Myocarditis?

    NARCIS (Netherlands)

    de Vetten, Leanne; Bergman, Klasien A.; Elzenga, Nynke J.; van Melle, Joost P.; Timmer, Albertus; Bartelds, Beatrijs

    We report a 29 week-gestation preterm infant who presented during his second week of life with cardiogenic shock. Clinical presentation and first diagnostics suggested myocardial infarction, but echocardiographic features during follow-up pointed to a diagnosis of enteroviral myocarditis. The child

  11. Thrombolysis in acute myocardial infarction

    NARCIS (Netherlands)

    F. Vermeer (Frank)

    1987-01-01

    textabstractThe purpose of this study was to analyse the effects of thrombolytic therapy with intracoronary streptokinase in patients with acute myocardial infarction. Five centres participated in the study, the Thorax center in Rotterdam (237 patients), the Academic Hospital of the Free

  12. Dosimetry in myocardial perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Toledo, Janine M.; Trindade, Bruno; Ribeiro, Tarcisio P.C. [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte (Brazil). Dept. de Engenharia Nuclear. Programa de Pos-Graduacao em Ciencias e Tecnicas Nucleares

    2011-07-01

    This paper conducts a dosimetric investigation on the myocardial perfusion image protocol, together with a literature reviewing, motivated by the significant statistic increasing on mortality, morbidity and disability associated with cardiovascular disease, surpassing infectious diseases. Nuclear Cardiology plays a role n the diagnostic functional evaluation of the heart and in the prognostic of patients with suspected or known cardiac ischemia. In the context of unstable myocardial ischemic syndrome, myocardial perfusion scintigraphy is a non-invasive procedure performed by administering a radiopharmaceutical targeted to the heart. As tool for this study are that the images obtained by thoracic angiotomography and abdominal aorta as a anatomic and functional information for model reproduction in SISCODES - System of Codes for Absorbed Dose Calculations based on Stochastic Methods. Data were manipulated in order to create a voxel computational model of the heart to be running in MCNP - Monte Carlo Neutron Particle Code. . It was assumed a homogeneous distribution of Tl-201 in cardiac muscle. Simulations of the transport of particles through the voxel and the interaction with the heart tissue were performed. As a result, the isodose curves in the heart model are displayed as well as the dose versus volume histogram of the heart muscle. We conclude that the present computational tools can generate doses distributed in myocardial perfusion. (author)

  13. Cardiovascular magnetic resonance: myocardial perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Nagel, E.; Al-Saadi, N.; Fleck, E. [Dept. of Internal Medicine/Cardiology, German Heart Inst. Berlin and Charite, Campus Virchow, Humboldt Univ. (Germany)

    2000-06-01

    There is growing evidence that the noninvasive assessment of myocardial perfusion with cardiovascular magnetic resonance is a valid and accurate tool for the assessment of ischemic heart disease and its introduction into routine clinical evaluation of patients is rapidly expected. Magnetic resonance measurements allow the evaluation of reversible and irreversible myocardial ischemia, the assessment of acute myocardial infarction, as well as the recognition and detection of viable myocardium. Magnetic resonance perfusion measurements are mainly performed with T1-shortening contrast agents such as gadolinium-DTPA either by visual analysis or based on the analyses of signal intensity time curves. For the detection of myocardial ischemia the first pass kinetics of a gadolinium-DTPA bolus and for the detection of myocardial necrosis and the definition of viable myocardium steady state distribution kinetics are assessed. Quantitative analysis of myocardial perfusion can be performed but requires complex modeling due to the characteristics of gadolinium-DTPA. Thus, semi-quantitative parameters are preferred. There is accumulating evidence in the literature that magnetic resonance imaging can be used for the detection of coronary artery stenosis with high diagnostic accuracy both with semi-quantitative or visual analysis. Myocardial infarction can be reliably detected and the infarcted area determined. Non-reperfused infarcted myocardium can be differentiated from reperfused myocardium by different enhancement patterns that correlates with viability. (orig.) [German] Die Magnetresonanztomographie (MR) erlangt bei der nichtinvasiven Diagnostik der koronaren Herzerkrankung eine zunehmende Bedeutung. Mit dieser Technik koennen sowohl die globale und regionale Myokardfunktion als auch die myokardiale Perfusion exakt beurteilt werden. Bisher liegen die meisten Daten fuer die Analyse von Wandbewegungsstoerun-gen unter Belastung vor, wobei sich eine deutliche diagnostische

  14. Nonspecific competition underlies transient attention

    NARCIS (Netherlands)

    Wilschut, A.M.; Theeuwes, J.; Olivers, C.N.L.

    2015-01-01

    Cueing a target by abrupt visual stimuli enhances its perception in a rapid but short-lived fashion, an effect known as transient attention. Our recent study showed that when targets are cued at a constant, central location, the emergence of the transient performance pattern was dependent on the

  15. Transients by substructuring with DMAP

    Science.gov (United States)

    Butler, T. G.

    1978-01-01

    Automated substructuring in level 16 of NASTRAN was employed as a preface to the solution of a direct transient analysis. The DMAP ALTER statements written to adapt the substructuring for transient purposes are explained. Data recovery was accomplished with transfer functions. Proof of the success of the method is presented with an application to a missile structure.

  16. Ion Acceleration Inside Foreshock Transients

    Science.gov (United States)

    Liu, Terry Z.; Lu, San; Angelopoulos, Vassilis; Lin, Yu; Wang, X. Y.

    2018-01-01

    Recent observations upstream of Earth's bow shock have revealed that foreshock transients can not only accelerate solar wind ions by reflection at their upstream boundaries but may also accelerate ions inside them. Evidence for the latter comes from comparisons of ion spectra inside and outside the cores, and from evidence of leakage of suprathermal ions from the cores. However, definite evidence for, and the physics of, ion acceleration in the foreshock transients are still open questions. Using case studies of foreshock transients from Time History of Events and Macroscale Interactions during Substorms observations, we reveal an ion acceleration mechanism in foreshock transients that is applicable to 25% of the transients. The ion energy flux is enhanced between several keV to tens of keV in the cores. We show that these energetic ions are reflected at the earthward moving boundary of foreshock transients, are accelerated through partial gyration along the convection electric field, and can leak out both upstream and downstream of the foreshock transients. Using ions moving self-consistently with a generic 3-D global hybrid simulation of a foreshock transient, we confirm this physical picture of ion acceleration and leakage. These accelerated ions could be further accelerated at the local bow shock and repopulate the foreshock, increasing the efficacy of solar wind-magnetosphere interactions.

  17. Pressure transients in pipeline systems

    DEFF Research Database (Denmark)

    Voigt, Kristian

    1998-01-01

    This text is to give an overview of the necessary background to do investigation of pressure transients via simulations. It will describe briefly the Method of Characteristics which is the defacto standard for simulating pressure transients. Much of the text has been adopted from the book Pressur...

  18. Value of first day angiography/angioplasty in evolving Non-ST segment elevation myocardial infarction: an open multicenter randomized trial. The VINO Study.

    Science.gov (United States)

    Spacek, R; Widimský, P; Straka, Z; Jiresová, E; Dvorák, J; Polásek, R; Karel, I; Jirmár, R; Lisa, L; Budesínský, T; Málek, F; Stanka, P

    2002-02-01

    Direct angioplasty is an effective treatment for ST-elevation myocardial infarction. The role of very early angioplasty in non-ST-elevation infarction is not known. Thus, a randomized study of first day angiography/angioplasty vs early conservative therapy of evolving myocardial infarction without persistent ST-elevation was conducted. One hundred and thirty-one patients with confirmed acute myocardial infarction without ST-segment elevations were randomized within 24 h of last rest chest pain: 64 in the first day angiography/angioplasty group and 67 in the early conservative group (coronary angiography only after recurrent or stress induced myocardial ischaemia). All patients in the invasive group underwent coronary angiography on the day of admission (mean randomization-angiography time 6.2 h). First day angioplasty of the infarct related artery was performed in 47% of the patients and bypass surgery in 35%. In the conservative group, 55% underwent coronary angiography, 10% angioplasty and 30% bypass surgery within 6 months. The primary end-point (death/reinfarction) at 6 months occurred in 6.2% vs 22.3% (P<0.001). Six month mortality in the first day angiography/angioplasty group was 3.1% vs 13.4% in the conservative group (P<0.03). Non-fatal reinfarction occurred in 3.1% vs. 14.9% (P<0.02). First day coronary angiography followed by angioplasty whenever possible reduces mortality and reinfarction in evolving myocardial infarction without persistent ST-elevation, in comparison with an early conservative treatment strategy. Copyright 2001 The European Society of Cardiology.

  19. Myocardial ischemia in Kawasaki disease

    International Nuclear Information System (INIS)

    Fukuda, Tsuyoshi

    1993-01-01

    The detection of myocardial ischemia is essential for evaluation of patients with Kawasaki disease, especially who have had coronary artery lesions. To evaluate the clinical efficacy of Tl-201 single photon emission computed tomography (SPECT) after dipyridamole infusion (maximum dose 0.70 mg/kg) for detecting myocardial ischemia, 44 patients with Kawasaki disease aged 7.7±4.8 years at the study and 10 age matched controls were observed. In the Kawasaki disease group, significant coronary artery stenosis was observed in 14, coronary aneurysm without stenosis in 18, the regression of the coronary aneurysms in 2 and without coronary lesions in 10 patients. In 24 of 44 patients, treadmill exercise stress test was also performed at the same period. Myocardial ischemic changes were observed in 11 patients, all combined with significant coronary artery stenosis. The sensitivity of SPECT for detection of overall coronary stenosis was 79%, coronary that of treadmill exercise test was only 33% (p<0.001). Furthermore, among the patients having significant coronary stenosis, the severity score was significantly elevated in patients who had electrocardiographic abnormal Q wave compared to those without abnormal Q wave (51.0±38.8 versus 20.0±12.1, p<0.05). These data suggest that the pharmacological stress scintigraphy using dipyridamole injection provides not only the accurate detection but quantitative evaluation of myocardial ischemia in these patients. This noninvasive technique may become one of the most useful index for detection and follow-up of myocardial ischemia in Kawasaki disease. (author)

  20. Transient Enhanced Diffusion

    Science.gov (United States)

    Gossmann, Hans-Joachim L.

    1996-03-01

    Ion implantation is the standard method for dopant introduction during integrated circuit manufacturing, determining crucial device characteristics. Implantation creates point-defects, such as Si self-interstitials and vacancies, far in excess of equilibrium concentrations. Since the diffusion of common dopants involves Si point defects, the interaction of damage and dopants during subsequent annealing steps leads to the phenomenon known as "transient enhanced diffusion" (TED): The dopant diffusivities are enhanced, possibly by many orders of magnitude. The enhancement is transient since the intrinsic defects eventually diffuse into the bulk or annihilate at the surface. The desired specific dopant profile of the device is thus the result of a complex reaction, involving the creation of damage and its spatial distribution, diffusion, and interaction of the point defects among themselves and with interfaces and other defects. As device dimensions shrink and experiments become more and more expensive, the capability to predict these kinds of non-equilibrium phenomena accurately becomes crucial to Si technology development. In our experiments to extract physical mechanisms and parameters of TED we use the method of sharp B- and Sb doping spikes to track interstitial and vacancy concentrations as a function of depth during processing. Thus we gain sensitivity to small diffusion distances (low temperatures) and separate the damaged region from the region of the interaction with dopants. In addition, our method yields directly the actual point defect diffusivity. Although an ion implant initially produces Frenkel pairs, Monte-carlo simulations show that the vacancies annihilate quickly. The excess interstitials, roughly one for each implanted ion coalesce into 311defects. The subsequent evaporation of interstitials from 311ś drives TED. Si interstitial diffusion is influenced by carbon-related traps and we will demonstrate that this finding reconciles quantitatively a

  1. Lentiviral vector mediated modification of mesenchymal stem cells & enhanced survival in an in vitro model of ischaemia.

    LENUS (Irish Health Repository)

    McGinley, Lisa

    2012-01-31

    INTRODUCTION: A combination of gene and cell therapies has the potential to significantly enhance the therapeutic value of mesenchymal stem cells (MSCs). The development of efficient gene delivery methods is essential if MSCs are to be of benefit using such an approach. Achieving high levels of transgene expression for the required period of time, without adversely affecting cell viability and differentiation capacity, is crucial. In the present study, we investigate lentiviral vector-mediated genetic modification of rat bone-marrow derived MSCs and examine any functional effect of such genetic modification in an in vitro model of ischaemia. METHODS: Transduction efficiency and transgene persistence of second and third generation rHIV-1 based lentiviral vectors were tested using reporter gene constructs. Use of the rHIV-pWPT-EF1-alpha-GFP-W vector was optimised in terms of dose, toxicity, cell species, and storage. The in vivo condition of ischaemia was modelled in vitro by separation into its associated constituent parts i.e. hypoxia, serum and glucose deprivation, in which the effect of therapeutic gene over-expression on MSC survival was investigated. RESULTS: The second generation lentiviral vector rHIV-pWPT-EF1-alpha-GFP-W, was the most efficient and provided the most durable transgene expression of the vectors tested. Transduction with this vector did not adversely affect MSC morphology, viability or differentiation potential, and transgene expression levels were unaffected by cryopreservation of transduced cells. Over-expression of HSP70 resulted in enhanced MSC survival and increased resistance to apoptosis in conditions of hypoxia and ischaemia. MSC differentiation capacity was significantly reduced after oxygen deprivation, but was preserved with HSP70 over-expression. CONCLUSIONS: Collectively, these data validate the use of lentiviral vectors for efficient in vitro gene delivery to MSCs and suggest that lentiviral vector transduction can facilitate

  2. Lentiviral vector mediated modification of mesenchymal stem cells & enhanced survival in an in vitro model of ischaemia

    LENUS (Irish Health Repository)

    McGinley, Lisa

    2011-03-07

    Abstract Introduction A combination of gene and cell therapies has the potential to significantly enhance the therapeutic value of mesenchymal stem cells (MSCs). The development of efficient gene delivery methods is essential if MSCs are to be of benefit using such an approach. Achieving high levels of transgene expression for the required period of time, without adversely affecting cell viability and differentiation capacity, is crucial. In the present study, we investigate lentiviral vector-mediated genetic modification of rat bone-marrow derived MSCs and examine any functional effect of such genetic modification in an in vitro model of ischaemia. Methods Transduction efficiency and transgene persistence of second and third generation rHIV-1 based lentiviral vectors were tested using reporter gene constructs. Use of the rHIV-pWPT-EF1-α-GFP-W vector was optimised in terms of dose, toxicity, cell species, and storage. The in vivo condition of ischaemia was modelled in vitro by separation into its associated constituent parts i.e. hypoxia, serum and glucose deprivation, in which the effect of therapeutic gene over-expression on MSC survival was investigated. Results The second generation lentiviral vector rHIV-pWPT-EF1-α-GFP-W, was the most efficient and provided the most durable transgene expression of the vectors tested. Transduction with this vector did not adversely affect MSC morphology, viability or differentiation potential, and transgene expression levels were unaffected by cryopreservation of transduced cells. Over-expression of HSP70 resulted in enhanced MSC survival and increased resistance to apoptosis in conditions of hypoxia and ischaemia. MSC differentiation capacity was significantly reduced after oxygen deprivation, but was preserved with HSP70 over-expression. Conclusions Collectively, these data validate the use of lentiviral vectors for efficient in vitro gene delivery to MSCs and suggest that lentiviral vector transduction can facilitate

  3. Applied hydraulic transients

    CERN Document Server

    Chaudhry, M Hanif

    2014-01-01

    This book covers hydraulic transients in a comprehensive and systematic manner from introduction to advanced level and presents various methods of analysis for computer solution. The field of application of the book is very broad and diverse and covers areas such as hydroelectric projects, pumped storage schemes, water-supply systems, cooling-water systems, oil pipelines and industrial piping systems. Strong emphasis is given to practical applications, including several case studies, problems of applied nature, and design criteria. This will help design engineers and introduce students to real-life projects. This book also: ·         Presents modern methods of analysis suitable for computer analysis, such as the method of characteristics, explicit and implicit finite-difference methods and matrix methods ·         Includes case studies of actual projects ·         Provides extensive and complete treatment of governed hydraulic turbines ·         Presents design charts, desi...

  4. Study progress of cardiac MRI technology in assessment of myocardial viability after myocardial infarction

    International Nuclear Information System (INIS)

    Wang Jing; Zhang Hao

    2013-01-01

    Acute myocardial infarction (AMI) is one of the most common diseases that cause disability and death around the world. Correctly and effectively assessing the myocardial viability after myocardial infarction can reduce the disabled rate and mortality rate. At present, many methods could be used to assess myocardial viability. The cardiac magnetic resonance imaging (CMR) technology has a lot of advantages compared to other methods. In this paper, we reviewed the research progress of CMR in assessment of myocardial viability after myocardial infarction, and compared CMR with other technologies. (authors)

  5. Myocardial calcium overload during graded hypothermia and after rewarming in an in vivo rat model.

    Science.gov (United States)

    Wold, R M; Kondratiev, T; Tveita, T

    2013-03-01

    Mechanisms underlying cardiac contractile dysfunction during and after rewarming from hypothermia remain largely unknown. We have previously reported myocardial post-hypothermic calcium overload to be the culprit. The aim of the present study was to measure changes in myocardial [Ca(2+) ](i) during graded hypothermia and after rewarming in an anesthetized, intact rat model, using the (45) Ca(2+) technique. Rats were randomized and cooled to 15 °C. Hearts were excised and perfusion-washed to remove extracellular calcium after 0.5 h of hypothermia (n = 9), 4 h of hypothermia (n = 8), and after 4 h of hypothermia and 2 h rewarming (n = 9). A normothermic group, kept at 37 °C for 5 h, served as control (n = 6). [Ca(2+) ](i) was determined in perchloric acid extracts of heart tissue. Spontaneous cardiac electromechanic work was maintained during hypothermia without cardiac arrest or ischaemia. Between 0.5 and 4 h at 15 °C, a six-fold increase in cardiac [Ca(2+) ](i) was observed (0.55 ± 0.10 vs. 2.93 ± 0.76 μmol (g dry wt)(-1) ). Rewarming resulted in a 33% decline in [Ca(2+) ](i) , but the actual value was significantly above the value measured in control hearts. We show that calcium overload is a characteristic feature of the beating heart during deep hypothermia, which aggravates by increasing duration of exposure. The relatively low decline in [Ca(2+) ](i) during the rewarming period indicates difficulties in recovering calcium homoeostasis, which in turn may explain cardiac contractile dysfunction observed after rewarming. © 2012 The Authors Acta Physiologica © 2012 Scandinavian Physiological Society.

  6. Use of myocardial perfusion imaging to predict the effectiveness of coronary revascularisation in patients with stable angina pectoris

    International Nuclear Information System (INIS)

    Johansen, Allan; Hoeilund-Carlsen, Poul Flemming; Moeldrup, Mette; Christensen, Henrik Wulff; Vach, Werner; Haghfelt, Torben

    2005-01-01

    Coronary revascularisation is the treatment of choice in patients with stable angina who have significant stenoses. From a pathophysiological point of view, however, mitigation of angina is to be expected only in the presence of reversible ischaemia. Therefore it was the aim of this study to examine the effect of revascularisation on stable angina in relation to the myocardial perfusion imaging (MPI) pattern prior to intervention. Three hundred and eighty-four patients (58.0±8.8 years) referred for angiography underwent MPI. Prior to MPI and at 2-year follow-up, patients were classified as having typical angina, atypical angina, non-cardiac chest pain or no pain, and the severity of chest pain was graded according to the Canadian Cardiovascular Society (CCS) criteria. The patients themselves estimated their pain on a visual analogue scale. Management was based on symptoms and angiographic findings, since the results of MPI were not communicated. Among the 240 patients who were not revascularised, 79% had typical or atypical angina at study entrance versus 40% at follow-up. In comparison, 93% of the 144 revascularised patients had typical or atypical angina before intervention versus only 36% at follow-up. This additional advantage of invasive therapy was present only in patients with reversible defects; revascularisation had no additional effect in patients with normal perfusion or irreversible defects. Similarly, additional, significant reductions in CCS class and visual analogue score were observed exclusively in patients with reversible defects. In patients referred for coronary angiography owing to known or suspected stable angina, revascularisation was significantly more effective than medical treatment exclusively in patients with reversible ischaemia. (orig.)

  7. Use of myocardial perfusion imaging to predict the effectiveness of coronary revascularisation in patients with stable angina pectoris

    Energy Technology Data Exchange (ETDEWEB)

    Johansen, Allan [Odense University Hospital, Department of Clinical Physiology and Nuclear Medicine, Odense (Denmark); Odense University Hospital, Department of Nuclear Medicine, Odense (Denmark); Hoeilund-Carlsen, Poul Flemming; Moeldrup, Mette [Odense University Hospital, Department of Clinical Physiology and Nuclear Medicine, Odense (Denmark); Christensen, Henrik Wulff [Nordic Institute of Chiropractic and Clinical Biomechanics, Odense (Denmark); Vach, Werner [University of Southern Denmark, Department of Statistics, Odense (Denmark); Haghfelt, Torben [Odense University Hospital, Department of Cardiology, Odense (Denmark)

    2005-12-01

    Coronary revascularisation is the treatment of choice in patients with stable angina who have significant stenoses. From a pathophysiological point of view, however, mitigation of angina is to be expected only in the presence of reversible ischaemia. Therefore it was the aim of this study to examine the effect of revascularisation on stable angina in relation to the myocardial perfusion imaging (MPI) pattern prior to intervention. Three hundred and eighty-four patients (58.0{+-}8.8 years) referred for angiography underwent MPI. Prior to MPI and at 2-year follow-up, patients were classified as having typical angina, atypical angina, non-cardiac chest pain or no pain, and the severity of chest pain was graded according to the Canadian Cardiovascular Society (CCS) criteria. The patients themselves estimated their pain on a visual analogue scale. Management was based on symptoms and angiographic findings, since the results of MPI were not communicated. Among the 240 patients who were not revascularised, 79% had typical or atypical angina at study entrance versus 40% at follow-up. In comparison, 93% of the 144 revascularised patients had typical or atypical angina before intervention versus only 36% at follow-up. This additional advantage of invasive therapy was present only in patients with reversible defects; revascularisation had no additional effect in patients with normal perfusion or irreversible defects. Similarly, additional, significant reductions in CCS class and visual analogue score were observed exclusively in patients with reversible defects. In patients referred for coronary angiography owing to known or suspected stable angina, revascularisation was significantly more effective than medical treatment exclusively in patients with reversible ischaemia. (orig.)

  8. The clinical course of critical limb ischaemia and the role of endovascular revascularisation in patients with diabetes

    Directory of Open Access Journals (Sweden)

    Olga Nikolaevna Bondarenko

    2015-05-01

    Full Text Available Recent data suggest that chronic critical limb ischaemia (CLI is the most important reason for amputation among diabetic patients. The high prevalence of CLI in this patient group is associated with specific clinical and morphological properties of peripheral arterial disease. Percutaneous transluminal angioplasty is an appropriate primary therapy, but it is not considered early in the disease process, and is instead reserved as a limb salvage strategy. Low primary patency, despite optimal clinical effects, remains a typical issue of percutaneous transluminal angioplasty for diabetic patients in particular. Thus, the indications, technical success and clinical results of endovascular revascularisation need to be clarified in patients with diabetes. Although difficult, the procedure can be effective through a multidisciplinary approach.

  9. Evolving changes in fetal heart rate variability and brain injury after hypoxia-ischaemia in preterm fetal sheep.

    Science.gov (United States)

    Yamaguchi, Kyohei; Lear, Christopher A; Beacom, Michael J; Ikeda, Tomoaki; Gunn, Alistair J; Bennet, Laura

    2018-01-08

    Fetal heart rate variability is a critical index of fetal wellbeing. Suppression of heart rate variability may provide prognostic information on the risk of hypoxic-ischaemic brain injury after birth. In the present study, we report the evolution of fetal heart rate variability after both mild and severe hypoxia-ischaemia. Both mild and severe hypoxia-ischaemia were associated with an initial, brief suppression of multiple measures of heart rate variability. This was followed by normal or increased levels of heart rate variability during the latent phase of injury. Severe hypoxia-ischaemia was subsequently associated with the prolonged suppression of measures of heart rate variability during the secondary phase of injury, which is the period of time when brain injury is no longer treatable. These findings suggest that a biphasic pattern of heart rate variability may be an early marker of brain injury when treatment or intervention is probably most effective. Hypoxia-ischaemia (HI) is a major contributor to preterm brain injury, although there are currently no reliable biomarkers for identifying infants who are at risk. We tested the hypothesis that fetal heart rate (FHR) and FHR variability (FHRV) would identify evolving brain injury after HI. Fetal sheep at 0.7 of gestation were subjected to either 15 (n = 10) or 25 min (n = 17) of complete umbilical cord occlusion or sham occlusion (n = 12). FHR and four measures of FHRV [short-term variation, long-term variation, standard deviation of normal to normal R-R intervals (SDNN), root mean square of successive differences) were assessed until 72 h after HI. All measures of FHRV were suppressed for the first 3-4 h in the 15 min group and 1-2 h in the 25 min group. Measures of FHRV recovered to control levels by 4 h in the 15 min group, whereas the 25 min group showed tachycardia and an increase in short-term variation and SDNN from 4 to 6 h after occlusion. The measures of FHRV then progressively

  10. Lower limb ischaemia in patients with diabetic foot ulcers and gangrene: recognition, anatomic patterns and revascularization strategies.

    Science.gov (United States)

    Mills, Joseph L

    2016-01-01

    The confluence of several chronic conditions--in particular ageing, peripheral artery disease, diabetes, and chronic kidney disease--has created a global wave of lower limbs at risk for major amputation. While frequently asymptomatic or not lifestyle limiting, at least 1% of the population has peripheral artery disease of sufficient severity to be limb threatening. To avoid the critical error of failing to diagnose ischaemia, all patients with diabetic foot ulcers and gangrene should routinely undergo physiologic evaluation of foot perfusion. Ankle brachial index is useful when measurable, but may be falsely elevated or not obtainable in as many as 30% of patients with diabetic foot ulcers primarily because of medial calcinosis. Toe pressures and skin perfusion pressures are applicable to such patients. Copyright © 2016 John Wiley & Sons, Ltd.

  11. Biochemical indications of cerebral ischaemia and mitochondrial dysfunction in severe brain trauma analysed with regard to type of lesion

    DEFF Research Database (Denmark)

    Nordström, Carl-Henrik; Nielsen, Troels Halfeld; Schalén, Wilhelm

    2016-01-01

    The study focuses on three questions related to the clinical usefulness of microdialysis in severe brain trauma: (1) How frequently is disturbed cerebral energy metabolism observed in various types of lesions? (2) How often does the biochemical pattern indicate cerebral ischaemia and mitochondrial...... dysfunction? (3) How do these patterns relate to mortality? The study includes 213 consecutive patients with severe brain trauma (342 intracerebral microdialysis catheters). The patients were classified into four groups according to the type of lesion: extradural haematoma (EDH), acute subdural haematoma (SDH......), cerebral haemorrhagic contusion (CHC) and no mass lesion (NML). Altogether about 150,000 biochemical analyses were performed during the initial 96 h after trauma. Compromised aerobic metabolism occurred during 38 % of the study period. The biochemical pattern indicating mitochondrial dysfunction was more...

  12. Multi-modal assessment of neurovascular coupling during cerebral ischaemia and reperfusion using remote middle cerebral artery occlusion

    DEFF Research Database (Denmark)

    Sutherland, Brad A; Fordsmann, Jonas C; Martin, Chris

    2017-01-01

    . Male Wistar rats were subjected to remote middle cerebral artery occlusion, where a long filament was advanced intraluminally through a guide cannula in the common carotid artery. Transcallosal stimulation evoked increases in blood flow, tissue oxygenation and neuronal activity, which were diminished......Hyperacute changes in cerebral blood flow during cerebral ischaemia and reperfusion are important determinants of injury. Cerebral blood flow is regulated by neurovascular coupling, and disruption of neurovascular coupling contributes to brain plasticity and repair problems. However, it is unknown...... by middle cerebral artery occlusion and partially restored during reperfusion. These evoked responses were not affected by administration of the thrombolytic alteplase at clinically used doses. Evoked cerebral blood flow responses were fully restored at 24 h post-middle cerebral artery occlusion indicating...

  13. [Ozone therapy and phototherapy with polarized polychromatic light in treatment of patients suffering from lower limb critical ischaemia].

    Science.gov (United States)

    Drozhzhin, E V; Sidorkina, O N

    2012-01-01

    The authors generalized their experience in treating a total of 77 patients presenting with atherosclerosis of the arteries of lower limbs with degree III-IV ischaemia according to the A.V. Pokrovsky-Fontain classification. The patients were subjected to comprehensive treatment including the impact of piler-light (apparatus Bioptron 2) and ozone therapy. The control group was composed of 66 people receiving conventional therapy. The two groups were comparable by the nosological entity of the disease, gender, age, and the nature of accompanying pathology. Despite carried out classical anticoagulation therapy there was a tendency towards hypercoagulation in phase I (formation of prothrombinase) and phase III (formation of fibrin) of plasma haemostasis, as well as insufficiency of the fibrinolytic system. The obtained results showed direct influence of ozone therapy and piler light on phase I and III plasmatic haemostasis, as well as enhanced fibrinolytic activity of blood on the background of their administration thereof.

  14. Changing circadian variation of transient myocardial ischemia during the first year after a first acute myocardial infarction

    DEFF Research Database (Denmark)

    Mickley, H; Pless, P; Nielsen, J R

    1992-01-01

    characteristics between the findings from discharge and 1-year ambulatory monitoring. The pathophysiologic processes underlying the observations from this study are unknown. The change in circadian periodicity could not be explained from differences in heart rate variation patterns or medical antianginal...

  15. Effect of verapamil on myocardial ischemia in patients with hypertrophic cardiomyopathy; Evaluation by exercise thallium-201 SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Taniguchi, Yoko; Sugihara, Hiroki; Ohtsuki, Katsuichi (Kyoto Prefectural Univ. of Medicine (Japan)) (and others)

    The effect of verapamil myocardial ischemia in patients with hypertrophic cardiomyopathy (HCM) was evaluated exercise myocardial [sup 201]TlSPECT (EX-Tl). EX-Tl was performed before and after 8.1[+-]6.1 weeks of oral administration of verapamil (240 mg/day) on 20 patients with HCM who showed transient [sup 201]Tl perfusion defects under control conditions. SPECT images were divided into nine segments. The [sup 201]Tl perfusion defect was visually scored and evaluated for four grades in each segment and the sum total grade was calculated as the defect score. Transient dilation index was calculated as a reflection of subendocardial ischemia. Improvements in defect score were demonstrated in 18 of 20 patients after administration of verapamil. The mean defect score decreased significantly from 5.1[+-]2.3 to 2.5[+-]2.4 (p<0.001). Although 18 of 20 patients showed abnormal transient dilation index under control conditions, 16 showed improvement and 12 were normalized after verapamil therapy. Mean transient dilation index decreased from 1.24[+-]0.19 to 1.08[+-]0.10 (p<0.01). Verapamil improves myocardial ischemia on patients with HCM. (author).

  16. HIF-1alpha and HIF-2alpha are differentially activated in distinct cell populations in retinal ischaemia.

    Directory of Open Access Journals (Sweden)

    Freya M Mowat

    2010-06-01

    Full Text Available Hypoxia plays a key role in ischaemic and neovascular disorders of the retina. Cellular responses to oxygen are mediated by hypoxia-inducible transcription factors (HIFs that are stabilised in hypoxia and induce the expression of a diverse range of genes. The purpose of this study was to define the cellular specificities of HIF-1alpha and HIF-2alpha in retinal ischaemia, and to determine their correlation with the pattern of retinal hypoxia and the expression profiles of induced molecular mediators.We investigated the tissue distribution of retinal hypoxia during oxygen-induced retinopathy (OIR in mice using the bio-reductive drug pimonidazole. We measured the levels of HIF-1alpha and HIF-2alpha proteins by Western blotting and determined their cellular distribution by immunohistochemistry during the development of OIR. We measured the temporal expression profiles of two downstream mediators, vascular endothelial growth factor (VEGF and erythropoietin (Epo by ELISA. Pimonidazole labelling was evident specifically in the inner retina. Labelling peaked at 2 hours after the onset of hypoxia and gradually declined thereafter. Marked binding to Müller glia was evident during the early hypoxic stages of OIR. Both HIF-1alpha and HIF-2alpha protein levels were significantly increased during retinal hypoxia but were evident in distinct cellular distributions; HIF-1alpha stabilisation was evident in neuronal cells throughout the inner retinal layers whereas HIF-2alpha was restricted to Müller glia and astrocytes. Hypoxia and HIF-alpha stabilisation in the retina were closely followed by upregulated expression of the downstream mediators VEGF and EPO.Both HIF-1alpha and HIF-2alpha are activated in close correlation with retinal hypoxia but have contrasting cell specificities, consistent with differential roles in retinal ischaemia. Our findings suggest that HIF-2alpha activation plays a key role in regulating the response of Müller glia to hypoxia.

  17. Mice Lacking the β2 Adrenergic Receptor Have a Unique Genetic Profile before and after Focal Brain Ischaemia

    Directory of Open Access Journals (Sweden)

    Robin E White

    2012-08-01

    Full Text Available The role of the β2AR (β2 adrenergic receptor after stroke is unclear as pharmacological manipulations of the β2AR have produced contradictory results. We previously showed that mice deficient in the β2AR (β2KO had smaller infarcts compared with WT (wild-type mice (FVB after MCAO (middle cerebral artery occlusion, a model of stroke. To elucidate mechanisms of this neuroprotection, we evaluated changes in gene expression using microarrays comparing differences before and after MCAO, and differences between genotypes. Genes associated with inflammation and cell deaths were enriched after MCAO in both genotypes, and we identified several genes not previously shown to increase following ischaemia (Ccl9, Gem and Prg4. In addition to networks that were similar between genotypes, one network with a central core of GPCR (G-protein-coupled receptor and including biological functions such as carbohydrate metabolism, small molecule biochemistry and inflammation was identified in FVB mice but not in β2KO mice. Analysis of differences between genotypes revealed 11 genes differentially expressed by genotype both before and after ischaemia. We demonstrate greater Glo1 protein levels and lower Pmaip/Noxa mRNA levels in β2KO mice in both sham and MCAO conditions. As both genes are implicated in NF-κB (nuclear factor κB signalling, we measured p65 activity and TNFα (tumour necrosis factor α levels 24 h after MCAO. MCAO-induced p65 activation and post-ischaemic TNFα production were both greater in FVB compared with β2KO mice. These results suggest that loss of β2AR signaling results in a neuroprotective phenotype in part due to decreased NF-κB signalling, decreased inflammation and decreased apoptotic signalling in the brain.

  18. Autoradiographic imaging of cerebral ischaemia using a combination of blood flow and hypoxic markers in an animal model

    International Nuclear Information System (INIS)

    Lythgoe, M.F.; Williams, S.R.; Wiebe, L.I.; McEwan, A.J.B.; Gordon, I.

    1997-01-01

    Current routine clinical techniques, including angiography and perfusional single-photon emission tomography, can be used to indicate problems in cerebral vascular supply and areas of cerebral hypoperfusion following a stroke, but cannot distinguish between ischaemic core and penumbra. In order to image specifically the penumbra, a method or indicator should be able to define areas with reduced blood flow, and a degree of metabolic compromise. In this context, the tissue could be regarded as hypoxic rather than ischaemic, and we have therefore chosen to investigate the potential of radio-labelled hypoxic markers in the study of ischaemia. In order to combine a hypoxic marker with a blood flow marker we used technetium-99m hexamethylpropylene amine oxime ( 99m Tc-HMPAO) and iodine-125 iodoazomycin arabinoside ( 125 I-IAZA), during cerebral ischaemia in the rat middle cerebral artery occlusion model. 99m Tc-HMPAO and 125 I-IAZA were injected simultaneously 2 h following occlusion of the middle cerebral artery, and 5 h before decapitation. Paired autoradiograms were produced and compared. Three distinct patterns emerged from the autoradiograms: slightly decreased perfusion with no uptake of the hypoxic marker indicating an area of misery perfusion; moderately decreased perfusion with concomitant uptake of iodoazomycin arabinoside, a region of hypoxia; and severely decreased perfusion with no retention of the hypoxic tracer. In conclusion, we present a new use for an imaging agent in the investigation of cerebral hypoxia. This agent, IAZA together with HMPAO, provides a means of separating the penumbra into regions of misery perfusion and hypoxia. The potential impact of this may be important in the clinical investigation of stroke. (orig.). With 3 figs

  19. Effects of N-acetyl-L-cysteine on renal haemodynamics and function in early ischaemia-reperfusion injury in rats.

    Science.gov (United States)

    Nitescu, Nicoletta; Grimberg, Elisabeth; Ricksten, Sven-Erik; Guron, Gregor

    2006-01-01

    1. Renal ischaemia-reperfusion (IR) severely compromises kidney function and has been shown to cause persistent abnormalities in intrarenal blood flow. The aim of the present study was to examine whether N-acetyl-L-cysteine (NAC), a thiol-containing anti-oxidant, improves renal haemodynamics and function during early reperfusion in rats subjected to renal IR. 2. Male Sprague-Dawley rats were divided into groups receiving either isotonic saline (IR-Saline; n = 8) or NAC (IR-NAC; n = 8) prior to (200 mg/kg, i.p., 24 and 12 h before acute experimentation) and during acute renal clearance experiments (bolus 150 mg/kg followed by a continuous infusion of 43 mg/kg per h, i.v.). During acute experimentation, thiobutabarbital-anaesthetized rats were subjected to a right-sided nephrectomy, followed by left kidney IR (40 min renal artery occlusion). Left kidney function and blood flow and intrarenal cortical and outer medullary perfusion measured by laser-Doppler flowmetry was analysed at baseline, during ischaemia and for 80 min of reperfusion. 3. Renal IR produced an approximate 85% reduction in glomerular filtration rate (GFR) and a pronounced increase in fractional urinary sodium excretion, throughout reperfusion, with no statistically significant differences between groups. 4. During reperfusion, total renal blood flow and cortical and outer medullary perfusion rapidly returned to levels not significantly different from baseline in both groups. The relative increase in renal vascular resistance in response to IR was more pronounced in NAC-treated rats compared with saline-treated animals (P < 0.05). 5. In conclusion, treatment with NAC did not improve kidney function during the first 80 min after renal IR. In addition, the marked reduction in GFR following reperfusion was not associated with any detectable abnormalities in intrarenal perfusion.

  20. Treating ischaemia-reperfusion injury with prostaglandin E1 reduces the risk of early hepatocellular carcinoma recurrence following liver transplantation.

    Science.gov (United States)

    Kornberg, A; Witt, U; Kornberg, J; Friess, H; Thrum, K

    2015-11-01

    Surgical stress by hepatic ischaemia-reperfusion (I/R) is supposed to promote intra- and extrahepatic tumour recurrence. Treatment with prostaglandin E1 (PGE1) has been shown to attenuate hepatic I/R injury in liver transplant patients, but the potential anti-cancer effects have not been analysed. To evaluate the impact of PGE1 therapy on risk of hepatocellular carcinoma (HCC) recurrence in liver transplant patients. A retrospective review of 106 liver transplant patients with HCC was conducted. Fifty-nine patients underwent early post-liver transplantation (LT) treatment with the stable PGE1 analogue alprostadil. Administration of alprostadil was correlated with outcome in uni- and multivariate analysis. Subgroup analysis focused on patients with HCC beyond the Milan criteria (Milan Out) on radiographic imaging. Three- and 5-year recurrence-free survival rates were 87.9% and 85.7% in the PGE1-group, but only 65.3% and 63.1% in the non-PGE1-population (P = 0.003). Multivariate Cox regression analysis identified absence of PGE1-treatment (HR = 11.42), along with presence of poor tumour grading (HR = 2.69) and microvascular tumour invasion (HR = 35.8) to be independently associated with early (within 12 months) HCC recurrence. In Milan Out-patients, only therapy with PGE1 (HR = 5.09) and well/moderate tumour differentiation (HR = 6.51) were independent promoters of recurrence-free survival. Treating hepatic ischaemia-reperfusion injury with alprostadil reduces the risk of early HCC recurrence following LT. In particular patients with HCC exceeding the Milan criteria seem to benefit from PGE1-treatment. The molecular mechanisms of the anti-tumour effects need to be further assessed. © 2015 John Wiley & Sons Ltd.

  1. Is chronic ST segment elevation a marker of myocardial non viability in patients with Q wave anteroseptal MI? Correlation with myocardial perfusion SPECT

    International Nuclear Information System (INIS)

    Padma, S.; Zachariah, M.; Haridas, K.K.

    2004-01-01

    Persistence of ST segment elevation for more than 2-4 weeks in patients with acute antero septal transmural myocardial infarction (ASMI) is considered to be a specific marker of left ventricular aneurysm. Objective: We attempted to assess the face value of this statement by correlating the findings of 99m Tc Sestamibi Myocardial perfusion SPECT (MPSPECT), one of the most specific modalities of myocardial viability assessment with resting 12 lead ECG. METHOD: 240 ASMI patients (192:48 Male: Female pts, age range 36-71 yrs Mean 51±8 yrs) referred for risk stratification to our department between Jan 02 -Jan 04 were retrospectively analysed. The baseline demographic details and LV systolic function parameters were more or less the same for all these patients. The mean LV EF at rest was 40±6 %. All these patients fulfilled the following inclusion criteri 1) Patients with Q Wave ASMt more than 1 month old, 2) ECG at rest showing sinus rhythm, QRS 1.5 mm. Patients with atrial arrhythmias and bundle branch block were excluded. All these patients underwent same day rest stress gated 99m Tc MIBI/ tetrofosmin MPSPECT on a dual head variable angle gamma camera. Patients performed either conventional treadmill stress or taken up for pharmacological stress. LAD territory myocardial segments (i.e. apex, anterior, septal) were evaluated for the presence of reversible ischaemia / viable myocardium. Images were visually interpreted and using a 16 segment myocardial model quantification was also performed. Presence of reversible perfusion defects, uptake of MIBI at rest more than 40 % and myocardial systolic wall thickening (count increase by at least 10% during systole) were considered as markers of viability. Results' Patients were categorized into two groups. ST elevation positive i.e. patients with rest ST elevation > 1.5 mm (137 pts 57%) and ST elevation negative (103 pts 37%) by the rest ECG criteria. In ST positive group, 47/137 pts (34%) showed viability (mean viable

  2. Electromagnetic transients in power cables

    CERN Document Server

    da Silva, Filipe Faria

    2013-01-01

    From the more basic concepts to the most advanced ones where long and laborious simulation models are required, Electromagnetic Transients in Power Cables provides a thorough insight into the study of electromagnetic transients and underground power cables. Explanations and demonstrations of different electromagnetic transient phenomena are provided, from simple lumped-parameter circuits to complex cable-based high voltage networks, as well as instructions on how to model the cables.Supported throughout by illustrations, circuit diagrams and simulation results, each chapter contains exercises,

  3. Myocardial infarction and stem cells

    Directory of Open Access Journals (Sweden)

    K Ananda Krishna

    2011-01-01

    Full Text Available Permanent loss of cardiomyocytes and scar tissue formation after myocardial infarction (MI results in an irreversible damage to the cardiac function. Cardiac repair (replacement, restoration, and regeneration is, therefore, essential to restore function of the heart following MI. Existing therapies lower early mortality rates, prevent additional damage to the heart muscle, and reduce the risk of further heart attacks. However, there is need for treatment to improve the infarcted area by replacing the damaged cells after MI. Thus, the cardiac tissue regeneration with the application of stem cells may be an effective therapeutic option. Recently, interest is more inclined toward myocardial regeneration with the application of stem cells. However, the potential benefits and the ability to improve cardiac function with the stem cell-based therapy need to be further addressed. In this review, we focus on the clinical applications of stem cells in the cardiac repair.

  4. Quantitative assessment of magnetic resonance derived myocardial perfusion measurements using advanced techniques: microsphere validation in an explanted pig heart system.

    Science.gov (United States)

    Schuster, Andreas; Zarinabad, Niloufar; Ishida, Masaki; Sinclair, Matthew; van den Wijngaard, Jeroen Phm; Morton, Geraint; Hautvast, Gilion Ltf; Bigalke, Boris; van Horssen, Pepijn; Smith, Nicolas; Spaan, Jos Ae; Siebes, Maria; Chiribiri, Amedeo; Nagel, Eike

    2014-10-14

    Cardiovascular Magnetic Resonance (CMR) myocardial perfusion imaging has the potential to evolve into a method allowing full quantification of myocardial blood flow (MBF) in clinical routine. Multiple quantification pathways have been proposed. However at present it remains unclear which algorithm is the most accurate. An isolated perfused, magnetic resonance (MR) compatible pig heart model allows very accurate titration of MBF and in combination with high-resolution assessment of fluorescently-labeled microspheres represents a near optimal platform for validation. We sought to investigate which algorithm is most suited to quantify myocardial perfusion by CMR at 1.5 and 3 Tesla using state of the art CMR perfusion techniques and quantification algorithms. First-pass perfusion CMR was performed in an MR compatible blood perfused pig heart model. We acquired perfusion images at physiological flow ("rest"), reduced flow ("ischaemia") and during adenosine-induced hyperaemia ("hyperaemia") as well as during coronary occlusion. Perfusion CMR was performed at 1.5 Tesla (n = 4 animals) and at 3 Tesla (n = 4 animals). Fluorescently-labeled microspheres and externally controlled coronary blood flow served as reference standards for comparison of different quantification strategies, namely Fermi function deconvolution (Fermi), autoregressive moving average modelling (ARMA), exponential basis deconvolution (Exponential) and B-spline basis deconvolution (B-spline). All CMR derived MBF estimates significantly correlated with microsphere results. The best correlation was achieved with Fermi function deconvolution both at 1.5 Tesla (r = 0.93, p Tesla (r = 0.9, p Tesla (p Tesla and showed the weakest correlation to microspheres (r = 0.74, p Tesla exponential deconvolution performed worst (r = 0.49, p model. Amongst the different techniques, Fermi function deconvolution was the most accurate technique at both field strengths. Perfusion CMR based on Fermi

  5. Mortality rate in type 2 myocardial infarction

    DEFF Research Database (Denmark)

    Saaby, Lotte; Poulsen, Tina Svenstrup; Diederichsen, Axel Cosmus Pyndt

    2014-01-01

    BACKGROUND: The classification of myocardial infarction into 5 types was introduced in 2007. The prognostic impact of this universal definition, with particular focus on type 2 myocardial infarction, has not been studied prospectively in unselected hospital patients. METHODS: During a 1-year period......, all hospitalized patients having cardiac troponin I measured were considered. The diagnosis of a myocardial infarction was according to the universal definition, and specified criteria were used in the classification of type 2 myocardial infarction. Follow-up was at least 1 year, with mortality...... as the end point. RESULTS: A total of 3762 consecutive patients were studied, of whom 488 (13%) had a myocardial infarction. In 119 patients a type 2 myocardial infarction was diagnosed. After a median of 2.1 years (interquartile range, 1.6-2.5 years), 150 patients had died, with a mortality rate of 49% (58...

  6. Novel adjunctive treatments of myocardial infarction

    DEFF Research Database (Denmark)

    Schmidt, Michael Rahbek; Pryds, Kasper; Bøtker, Hans Erik

    2014-01-01

    Myocardial infarction is a major cause of death and disability worldwide and myocardial infarct size is a major determinant of prognosis. Early and successful restoration of myocardial reperfusion following an ischemic event is the most effective strategy to reduce final infarct size and improve...... by endovascular infusion of cold saline all reduce infarct size and may confer clinical benefit for patients admitted with acute myocardial infarcts. Equally promising, three follow-up studies of the effect of remote ischemic conditioning (RIC) show clinical prognostic benefit in patients undergoing coronary...... clinical outcome, but reperfusion may induce further myocardial damage itself. Development of adjunctive therapies to limit myocardial reperfusion injury beyond opening of the coronary artery gains increasing attention. A vast number of experimental studies have shown cardioprotective effects of ischemic...

  7. Assessment of myocardial viability using PET

    International Nuclear Information System (INIS)

    Yoon, Seok Nam

    2005-01-01

    The potential for recovery of left ventricular dysfunction after myocardial revascularization represents a practical clinical definition for myocardial viability. The evaluation of viable myocardium in patients with severe global left ventricular dysfunction due to coronary artery disease and with regional dysfunction after acute myocardial infarction is an important issue whether left ventricular dysfunction may be reversible or irreversible after therapy. If the dysfunction is due to stunning or hibernation, functional improvement is observed. But stunned myocardium may recover of dysfunction with no revascularization. Hibernation is chronic process due to chronic reduction in the resting myocardial blood flow. There are two types of myocardial hibernation; 'functional hibernation' with preserved contractile reserve and 'structural hibernation' without contractile reserve in segments with preserved glucose metabolism. This review focus on the application of F-18 FDG and other radionuclides to evaluate myocardial viability. In addition the factors influencing predictive value of FDG imaging for evaluating viability and the different criteria for viability are also reviewed

  8. Cardiac MRI for myocardial ischemia.

    LENUS (Irish Health Repository)

    Daly, Caroline

    2013-01-01

    Proper assessment of the physiologic impact of coronary artery stenosis on the LV myocardium can affect patient prognosis and treatment decisions. Cardiac magnetic resonance imaging (CMR) assesses myocardial perfusion by imaging the myocardium during a first-pass transit of an intravenous gadolinium bolus, with spatial and temporal resolution substantially higher than nuclear myocardial perfusion imaging. Coupled with late gadolinium enhancement (LGE) imaging for infarction during the same imaging session, CMR with vasodilating stress perfusion imaging can qualitatively and quantitatively assess the myocardial extent of hypoperfusion from coronary stenosis independent of infarcted myocardium. This approach has been validated experimentally, and multiple clinical trials have established its diagnostic robustness when compared to stress single-photon emission computed tomography. In specialized centers, dobutamine stress CMR has been shown to have incremental diagnostic value above stress echocardiography due to its high imaging quality and ability to image the heart with no restriction of imaging window. This paper reviews the technical aspects, diagnostic utility, prognostic values, challenges to clinical adaptation, and future developments of stress CMR imaging.

  9. CHARACTERIZATION OF TRANSIENT PUFF EMISSIONS ...

    Science.gov (United States)

    Symposium Paper Transient puff emissions were characterized from burning carpet charges that were fed to a pilotscale rotary kiln combustor to assess the potential impact on emissions of using post-consumer carpet as an alternative fuel in cement kilns.

  10. Transient heating of moving objects

    Directory of Open Access Journals (Sweden)

    E.I. Baida

    2014-06-01

    Full Text Available A mathematical model of transient and quasistatic heating of moving objects by various heat sources is considered. The mathematical formulation of the problem is described, examples of thermal calculation given.

  11. Acute coronary vasospasm secondary to industrial nitroglycerin ...

    African Journals Online (AJOL)

    A Black employee exposed to industrial nitroglycerin (NG) in an explosives factory presented with severe precordial pain. The clinical presentation was that of significant transient anteroseptal and anterolateral transmural myocardial ischaemia which responded promptly to sublingual isosorbide dinitrate. Despite being ...

  12. Recurrent Acute Myocardial Infarction in Patients with Immune Thrombocytopenic Purpura

    Directory of Open Access Journals (Sweden)

    Fengyi Shen

    2014-01-01

    Full Text Available Immune thrombocytopenic purpura (ITP, also known as idiopathic thrombocytopenic purpura, is an acquired immune-mediated disease of adults and children characterized by a transient or persistent decrease of platelets and, depending upon the degree of thrombocytopenia, an increased risk of bleeding. The use of standard treatments for acute myocardial infarction (AMI, such as antiplatelet agents and anticoagulants, pose serious problems in patients with ITP due to the potential higher risk of bleeding complications. There are no current guidelines available for management of ITP patients with AMI. In this brief review of the limited available literature, we discuss the proposed pathophysiological link between ITP and arterial thrombosis and the challenging medical and interventional treatment of these patients.

  13. Left ventricular systolic wall motion after exercise stress and myocardial perfusion in patients with ischemic heart disease. Investigation by ECG gated myocardial tomography

    Energy Technology Data Exchange (ETDEWEB)

    Narita, Michihiro; Kurihara, Tadashi; Sindoh, Takashi; Sawada, Yoshihiro; Honda, Minoru [Sumitomo Hospital, Osaka (Japan)

    2001-01-01

    To investigate regional left ventricular (LV) wall motion (WM) after recovery from myocardial ischemia, we performed ECG-gated myocardial perfusion tomography with {sup 99m}Tc-MIBI (G-SPECT) in patients with ischemic heart disease (IHD). In addition, we compared the left ventricular (LV) systolic function obtained by G-SPECT at rest with that obtained by contrast left ventriculography (LVG). We performed G-SPECT at 30 minutes after exercise stress (Ex-30) and 3 hours after exercise (rest). LVWM and LV ejection fractions (EF) were analyzed by the QGS (quantitative gated SPECT) program. The LV was divided into 9 segments and regional WM (RWM) was analyzed quantitatively. In addition, myocardial perfusion was assessed quantitatively. In 64 patients with several different types of heart disease, EF obtained by G-SPECT correlated well with LVG-EF (r=0.907, p<0.001), and RWM of G-SPECT coincided well with that of LVG ({kappa} value 0.67, p<0.01). Eighty patients with suspected IHD were divided according to Ex-Rest myocardial perfusion. In 83% of patients with Ex-induced perfusion abnormalities disappeared completely at rest, and in 58% of patients with Ex-induced abnormalities disappeared incompletely, RWM abnormalities which were observed at Ex-30 improved at rest and as did EF. In 79% of patients with a fixed defect (FD), RWM abnormalities and EF at Ex-30 did not differ with those at rest, but in 12% of the patients, the RWM abnormality of Ex-30 improved at rest. In most myocardial segments that had recovered from transient ischemia, RWM abnormalities persisted at least 30 minutes after Ex (stunning). In a small portion of the myocardial segments regarded as having myocardial necrosis because of a fixed perfusion abnormality, RWM abnormalities at Ex-30 improved at rest. These segments were supposed to contain viable myocardium. In conclusion, G-SPECT is a powerful method for clarifying the relation between the regional systolic function and myocardial perfusion

  14. Transient two-phase flow

    International Nuclear Information System (INIS)

    Hsu, Y.Y.

    1974-01-01

    The following papers related to two-phase flow are summarized: current assumptions made in two-phase flow modeling; two-phase unsteady blowdown from pipes, flow pattern in Laval nozzle and two-phase flow dynamics; dependence of radial heat and momentum diffusion; transient behavior of the liquid film around the expanding gas slug in a vertical tube; flooding phenomena in BWR fuel bundles; and transient effects in bubble two-phase flow. (U.S.)

  15. Transient stability of superconducting alternators

    International Nuclear Information System (INIS)

    Furuyama, M.; Kirtley, J.L. Jr.

    1975-01-01

    A simulation study is performed for the purpose of determining the transient stability characteristics of superconducting alternators. This simulation is compared with an equal area criterion method. It is found that superconducting machines have good transient stability characteristics, that field forcing is not particularly helpful nor necessary. It is also found that the equal area criterion is useful for computing critical clearing times, if voltage behind subtransient reactance is held constant. (U.S.)

  16. Leukocytosis: a risk factor for myocardial infarction

    OpenAIRE

    Kotla, Suman

    2012-01-01

    Suman K KotlaDepartment of Internal Medicine, Memorial Medical Center, Johnstown, PA, USAAbstract: Myocardial infarction commonly results from atherosclerotic lesions in the coronary arteries. Approximately 5% of patients with acute myocardial infarction do not have atherosclerotic disease. In this case report, we present an unusual leukostatic complication in a patient with acute myeloblastic leukemia and extreme hyperleukocytosis who presented with an acute myocardial infarction that resolv...

  17. Value of myocardial perfusion SPECT in pediatric population

    International Nuclear Information System (INIS)

    Massardo, T.; Coll, C.; Prat, H.; Gonzalez, P.; Doggenweiller, P.; Castillo, M.E.; Solis, A.

    2002-01-01

    Isotopic myocardial perfusion studies are less frequently used in children than in adults and their indications are also different. Our goal was to analyze retrospectively the experience with stress perfusion myocardial SPECT in pediatric population. Method: Since 1998 to 2001, ten studies were performed to 5 girls and 3 boys. Their mean age was 7±3 years ranging from 1-11. Three of them presented abnormal coronary arteries pre and post surgical intervention with or without coil; three had Kawasaki disease with coronary aneurysms and the other two, congenital cardiopathies (Cantrell pentalogy and great vessel transposition,both with posterior left ventricular hypokinesia post surgery). Stress was obtained using dipyridamole infusion (0.56 mg/kg) in 6 cases and treadmill exercise using Bruce protocol in 4. All those tests were well tolerated. Sestamibi Tc99m was selected in 80% of the cases and Tl 201 in the rest. Only 2 small children required anesthesia during SPECT acquisition. Results: Stress EKG did not demonstrated ischemia in any case. Coronary angiography was performed only in 50% of the patients, it was concordant with SPECT features in all, two of those patients presented transient perfusion defects (one Kawasaki and one abnormal coronary artery with a fistulae).The repaired pentalogy presented ischemia and septal infarction; in that patient echocardiographic hipokinesia was concordant with fixed hypoperfusion. One case with abnormal coronary plus mitral regurgitation (without isotopic ischemia) was submitted to embolization posteriorly, obtaining motion improvement. Clinical outcome was concordant with the presence or absence of isotopic ischemia in the rest of the patients. Conclusion: SPECT myocardial perfusion was helpful in the therapeutic approach and in prediction of outcome in children

  18. The Frequency of Cerebral Microembolism in Acute Myocardial Infarction

    Directory of Open Access Journals (Sweden)

    Masoud Mehrpour

    2010-11-01

    Full Text Available ABSTRACT Introduction: Stroke is more common in patients with cerebral microembolisms. Frequency of cerebral microembolisms (high intensity transient signals, HITS in acute myocardial infarction has been reported about 17%. The factors that influence on microembolism after myocardial infarction (MI are not definitive. Type of MI, Ejection fraction, Hx of Streptokinase is the factors that were studied. Methods: During three years we studied the frequency of cerebral microembolisms in AMI patients, we studied forty patients with microembolism as a case group and ninety patients without microembolism as a control group. We detected microembolism in patients by transcranial doppler study within 72 houre after myocardial infarction. Two-dimensional echocardiogram was performed for all patients during hospitalization. Excluding criteria were prosthetic heart valves, carotid stenosis >50% and poor window for TCD monitoring. Results: number of patients who had history of receiving SK were significantly more common in case group in comparison to control group. OR 2.4 CI(1.1-5.2 The frequency was more prevalent in anterolateral MI in comparison to inferior MI.OR=3.3 CI(1.4-7.4. Ejection fraction has no significant effect on frequency of microembolism. OR 0.5 CI(0.2-1.3.Hypokinesia is also a risk factor for increasing risk of microembolism. OR 4.5 CI(1.4.13.8 Discussion: frequency of microembolism has been increased in patients with history of streptokinase or in the type of Anterolateral MI or wall motion abnormality, so we should be careful for risk of microembolism in this groups.

  19. Different Causes of Death in Patients with Myocardial Infarction Type 1, Type 2 and Myocardial Injury

    DEFF Research Database (Denmark)

    Lambrecht, S; Sarkisian, Laura; Saaby, Lotte

    2017-01-01

    BACKGROUND: Data outlining the mortality and the causes of death in patients with type 1 myocardial infarction, type 2 myocardial infarction and those with myocardial injury are limited. METHODS: During a 1-year period from January 2010 to January 2011 all hospitalized patients, who had cardiac t...

  20. Increases in myeloperoxidase levels after exercise in myocardial perfusion scintigraphy are not induced by myocardial ischemia

    NARCIS (Netherlands)

    van der Zee, P. M.; Meuwese, M. C.; Verberne, H. J.; de Ruijter, M.; van Straalen, J. P.; Fischer, J. C.; Sturk, A.; van Eck-Smit, B. L. F.; Stroes, E. S. G.; de Winter, R. J.

    2008-01-01

    Background: Increased systemic levels of myeloperoxidase (MPO) have been reported in patients with acute myocardial ischemia. We studied the association between exercise-induced myocardial ischemia measured by myocardial perfusion scintigraphy (MPS) and the magnitude and time course of changes in

  1. Risk-benefit of dipyridamole loading thallium-201 myocardial scintigraphy

    International Nuclear Information System (INIS)

    Ueshima, Kenji; Ogiu, Naonori; Musha, Takehiko; Moriai, Naoki; Miyakawa, Tomohisa; Nakai, Kenji; Hiramori, Katsuhiko

    1995-01-01

    This study assessed the accuracy of dipyridamole-stressed thallium-201 scintigraphy in the detection of myocardial ischemia, as well as the associated complications and their background factors. Fifty consecutive patients (33 men and 17 women; a mean age of 67 years) unable to undergo exercise thallium imaging were examined. R waves on resting ECG, the occurrence of ischemic changes on exercise ECG, asynergy on left ventriculography and dobutamine-stressed two-dimensional echocardiography, uptake of FEG on PET, and coronary angiographic findings were comprehensively assessed to determine the accuracy of the present scintigraphy. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 60.4%, 94.2%, 89.7%, 83.0%, and 82.9%, respectively. These findings yielded satisfactory detectability of dipyridamole-stressed thallium-201 scintigraphy for myocardial ischemia. The present scintigraphy had a high sensitivity and specificity for the left anterior descending artery; however, it had a high specificity but low sensitivity for the other arteries. A majority of complications during the scintigraphy was transient, mild decrease in blood pressure, which was found especially when ischemia was present in the left circumflex artery and chest pain occurred during dipyridamole stress. Dipyridamole stress is considered to be contraindicated for patients with unstable angina. (N.K.)

  2. Routine myocardial revascularization with the radial artery: a multicenter experience.

    Science.gov (United States)

    Chen, A M; Brodman, R F; Frame, R; Graver, L M; Tranbaugh, R F; Banks, T; Hoffman, D; Palazzo, R S; Kline, G M; Stelzer, P; Harris, L; Sisto, D; Frymus, M; Frater, R W; Furlong, P; Wasserman, F; Cohen, B

    1998-01-01

    Current literature documents use of the radial artery (RA) for myocardial revascularization only as an alternative conduit in cases where the saphenous veins have been previously harvested or are unsuitable for use. Large-scale routine clinical use of the RA as the conduit of choice has not been reported. This prospective study evaluated the harvest of the RA from 933 patients and the subsequent use of the conduit as a preferred coronary artery bypass graft second only to the left internal thoracic artery in 930 of these patients. Unilateral RA harvest was performed in 786 patients and 147 patients had bilateral RA harvest. A total of 1080 RAs were harvested; 214 (19.8%) originated from the dominant forearm. There was a mean of 3.30+/-0.93 grafts per patient of which 2.43+/-0.83 were arterial grafts. The mean number of RA grafts was 1.43+/-0.53. Operative mortality was 2.3% with none due to the RA graft(s). There was no ischemia nor motor dysfunction in the operated hands. Thirty-two (3.4%) patients experienced transient thenar dysesthesia that resolved in 1 day to 6 weeks. Our results demonstrate that routine total or near total arterial myocardial revascularization may be achieved safely and effectively with the use of one or both RAs in conjunction with the internal thoracic artery.

  3. Exercise Tl-201 myocardial scintigraphy and coronary blood flow velocity in patients with hypertrophic cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Sugihara, Hiroki; Umamoto, Ikuo; Harada, Yoshiaki (Kyoto Prefectural Univ. of Medicine (Japan)) (and others)

    1992-03-01

    In 22 patients with hypertrophic cardiomyopathy not associated with coronary stenosis, findings of exercise Tl-201 myocardial scintigraphy were reviewed in relation to coronary blood flow velocity. Blood flow velocity of the left antero-inferior segment was recorded by using a Doppler catheter. From time velocity integration in systolic and diastolic phases, both % systolic fraction (%SF) and %diastolic 1st third fraction (%d1F) were obtained. A decreased perfusion was visually assessed on exercise Tl-201 myocardial images. In addition, transient dilation of the left ventricular cavity was quantitatively assessed by expressing it as a transient dilation index (TDI) for subendocardial ischemia. Coronary blood flow velocity was characterized by a decrease in both %SF and %d1F and negative systolic flow. Both %SF and %d1F were inversely correlated with TDI. Coronary negative systolic flow was frequently associated with a decreased perfusion. These results suggest factors such as left ventricular relaxation impairment, other than coronary small vessel lesions, may also be involved in the occurrence of myocardial ischemia in hypertrophic cardiomyopathy. (N.K.).

  4. Pioglitazone after Ischemic Stroke or Transient Ischemic Attack.

    Science.gov (United States)

    Kernan, Walter N; Viscoli, Catherine M; Furie, Karen L; Young, Lawrence H; Inzucchi, Silvio E; Gorman, Mark; Guarino, Peter D; Lovejoy, Anne M; Peduzzi, Peter N; Conwit, Robin; Brass, Lawrence M; Schwartz, Gregory G; Adams, Harold P; Berger, Leo; Carolei, Antonio; Clark, Wayne; Coull, Bruce; Ford, Gary A; Kleindorfer, Dawn; O'Leary, John R; Parsons, Mark W; Ringleb, Peter; Sen, Souvik; Spence, J David; Tanne, David; Wang, David; Winder, Toni R

    2016-04-07

    Patients with ischemic stroke or transient ischemic attack (TIA) are at increased risk for future cardiovascular events despite current preventive therapies. The identification of insulin resistance as a risk factor for stroke and myocardial infarction raised the possibility that pioglitazone, which improves insulin sensitivity, might benefit patients with cerebrovascular disease. In this multicenter, double-blind trial, we randomly assigned 3876 patients who had had a recent ischemic stroke or TIA to receive either pioglitazone (target dose, 45 mg daily) or placebo. Eligible patients did not have diabetes but were found to have insulin resistance on the basis of a score of more than 3.0 on the homeostasis model assessment of insulin resistance (HOMA-IR) index. The primary outcome was fatal or nonfatal stroke or myocardial infarction. By 4.8 years, a primary outcome had occurred in 175 of 1939 patients (9.0%) in the pioglitazone group and in 228 of 1937 (11.8%) in the placebo group (hazard ratio in the pioglitazone group, 0.76; 95% confidence interval [CI], 0.62 to 0.93; P=0.007). Diabetes developed in 73 patients (3.8%) and 149 patients (7.7%), respectively (hazard ratio, 0.48; 95% CI, 0.33 to 0.69; Pischemic stroke or TIA, the risk of stroke or myocardial infarction was lower among patients who received pioglitazone than among those who received placebo. Pioglitazone was also associated with a lower risk of diabetes but with higher risks of weight gain, edema, and fracture. (Funded by the National Institute of Neurological Disorders and Stroke; ClinicalTrials.gov number, NCT00091949.).

  5. Transient magnetoviscosity of dilute ferrofluids

    International Nuclear Information System (INIS)

    Soto-Aquino, Denisse; Rinaldi, Carlos

    2011-01-01

    The magnetic field induced change in the viscosity of a ferrofluid, commonly known as the magnetoviscous effect and parameterized through the magnetoviscosity, is one of the most interesting and practically relevant aspects of ferrofluid phenomena. Although the steady state behavior of ferrofluids under conditions of applied constant magnetic fields has received considerable attention, comparatively little attention has been given to the transient response of the magnetoviscosity to changes in the applied magnetic field or rate of shear deformation. Such transient response can provide further insight into the dynamics of ferrofluids and find practical application in the design of devices that take advantage of the magnetoviscous effect and inevitably must deal with changes in the applied magnetic field and deformation. In this contribution Brownian dynamics simulations and a simple model based on the ferrohydrodynamics equations are applied to explore the dependence of the transient magnetoviscosity for two cases: (I) a ferrofluid in a constant shear flow wherein the magnetic field is suddenly turned on, and (II) a ferrofluid in a constant magnetic field wherein the shear flow is suddenly started. Both simulations and analysis show that the transient approach to a steady state magnetoviscosity can be either monotonic or oscillatory depending on the relative magnitudes of the applied magnetic field and shear rate. - Research Highlights: →Rotational Brownian dynamics simulations were used to study the transient behavior of the magnetoviscosity of ferrofluids. →Damped and oscillatory approach to steady state magnetoviscosity was observed for step changes in shear rate and magnetic field. →A model based on the ferrohydrodynamics equations qualitatively captured the damped and oscillatory features of the transient response →The transient behavior is due to the interplay of hydrodynamic, magnetic, and Brownian torques on the suspended particles.

  6. Screening for silent myocardial ischemia caseof diabetics : interest of myocardial perfusion scintigraphy

    International Nuclear Information System (INIS)

    Bahri, Haifa

    2007-01-01

    Silent myocardial ischemia is a major cause of morbidity and mortality in diabetic patients. Its diagnosis by noninvasive means such as myocardial SPECT would improve the management of these patients. The purpose of this study is to assess the frequency of silent myocardial ischemia in asymptomatic diabetics and their evolution. As a result, the myocardial SPECT is a reliable tool for screening for silent myocardial ischemia in diabetic patients. Its prognostic value allows to stratify the cardiac risk and guide therapeutic management. Its integration into a screening strategy in Tunisia seems limited by its low availability and cost. The latter could be reduced by better patient selection.

  7. Trenbolone Improves Cardiometabolic Risk Factors and Myocardial Tolerance to Ischemia-Reperfusion in Male Rats With Testosterone-Deficient Metabolic Syndrome.

    Science.gov (United States)

    Donner, Daniel G; Elliott, Grace E; Beck, Belinda R; Bulmer, Andrew C; Lam, Alfred K; Headrick, John P; Du Toit, Eugene F

    2016-01-01

    The increasing prevalence of obesity adds another dimension to the pathophysiology of testosterone (TEST) deficiency (TD) and potentially impairs the therapeutic efficacy of classical TEST replacement therapy. We investigated the therapeutic effects of selective androgen receptor modulation with trenbolone (TREN) in a model of TD with the metabolic syndrome (MetS). Male Wistar rats (n=50) were fed either a control standard rat chow (CTRL) or a high-fat/high-sucrose (HF/HS) diet. After 8 weeks of feeding, rats underwent sham surgery or an orchiectomy (ORX). Alzet miniosmotic pumps containing either vehicle, 2-mg/kg·d TEST or 2-mg/kg·d TREN were implanted in HF/HS+ORX rats. Body composition, fat distribution, lipid profile, and insulin sensitivity were assessed. Infarct size was quantified to assess myocardial damage after in vivo ischaemia reperfusion, before cardiac and prostate histology was performed. The HF/HS+ORX animals had increased sc and visceral adiposity; circulating triglycerides, cholesterol, and insulin; and myocardial damage, with low circulating TEST compared with CTRLs. Both TEST and TREN protected HF/HS+ORX animals against sc fat accumulation, hypercholesterolaemia, and myocardial damage. However, only TREN protected against visceral fat accumulation, hypertriglyceridaemia, and hyperinsulinaemia and reduced myocardial damage relative to CTRLs. TEST caused widespread cardiac fibrosis and prostate hyperplasia, which were less pronounced with TREN. We propose that TEST replacement therapy may have contraindications for males with TD and obesity-related MetS. TREN treatment may be more effective in restoring androgen status and reducing cardiovascular risk in males with TD and MetS.

  8. Biventricular Mechanical Circulatory Support Does Not Prevent Delayed Myocardial Ventricular Rupture following Myocardial Infarction

    Directory of Open Access Journals (Sweden)

    Yazhini Ravi

    2013-01-01

    Full Text Available Cardiogenic shock and myocardial rupture can complicate an acute myocardial infarction (AMI. A case is reported in which a 58-year-old male with an acute inferior myocardial infarction required placement of biventricular assist device for hemodynamic support eight days after the onset of his AMI; eleven days after his AMI, the patient developed abrupt onset of hemodynamic instability with massive bleeding from his chest tube due to delayed free wall myocardial rupture that was discovered when he was taking emergently to the operating room. Myocardial rupture in patients with a ventricular assist device should be considered in the differential diagnosis in the event of acute hemodynamic compromise. A high level of suspicion for such a complication should prompt aggressive and emergent actions including surgery. We present a case of delayed free wall myocardial rupture following an acute inferior wall myocardial infarction in a patient with biventricular mechanical circulatory support.

  9. Recent development of transient electronics

    Directory of Open Access Journals (Sweden)

    Huanyu Cheng

    2016-01-01

    Full Text Available Transient electronics are an emerging class of electronics with the unique characteristic to completely dissolve within a programmed period of time. Since no harmful byproducts are released, these electronics can be used in the human body as a diagnostic tool, for instance, or they can be used as environmentally friendly alternatives to existing electronics which disintegrate when exposed to water. Thus, the most crucial aspect of transient electronics is their ability to disintegrate in a practical manner and a review of the literature on this topic is essential for understanding the current capabilities of transient electronics and areas of future research. In the past, only partial dissolution of transient electronics was possible, however, total dissolution has been achieved with a recent discovery that silicon nanomembrane undergoes hydrolysis. The use of single- and multi-layered structures has also been explored as a way to extend the lifetime of the electronics. Analytical models have been developed to study the dissolution of various functional materials as well as the devices constructed from this set of functional materials and these models prove to be useful in the design of the transient electronics.

  10. The role of a specialized approach for patients with diabetes, critical ischaemia and foot ulcers not previously considered for proactive management.

    Science.gov (United States)

    Aragón-Sánchez, J; Maynar-Moliner, M; Pulido-Duque, J M; Rabellino, M; González, G; Zander, T

    2011-10-01

    To analyse the outcome of the proactive management of patients with diabetes, critical limb ischaemia and foot ulcers using percutaneous transluminal angioplasty as the only vascular procedure and adjuvant conservative surgery when indicated. A retrospective study of patients with diabetes included in our database who sought a second opinion in our unit and met the following criteria: foot ulcer and critical limb ischaemia in patients for whom any proactive vascular treatment had not previously been considered by other teams. Twenty patients underwent endovascular procedures. Success was achieved in 19 cases (95%). No post-operative mortality (within 30 days after the procedure) was found. Additional surgery was required in eight cases (40%): one calcaneal ostectomy and seven minor amputations. The need for surgery was associated with infection (P diabetes, foot ulcers and critical limb ischaemia by means of a proactive approach including endovascular procedures in specialized settings provides a high rate of limb salvage. This may result in lowering the number of lower limb amputations in our community. © 2011 The Authors. Diabetic Medicine © 2011 Diabetes UK.

  11. Myocardial imaging in patients with Kawasaki disease

    International Nuclear Information System (INIS)

    Ono, Yasuo; Tanimoto, Takeshi; Kijima, Yoshitami; Kohata, Tohru; Suzuki, Atsuko

    1982-01-01

    Thallium-201 myocardial imaging was performed in 80 children with coronary arterial lesions due to Kawasaki disease in order to assess the value of serial and exercise myocardial imagings. In eight of these children, abnormalities of the image were noted. Twenty children had serial thallium studies with an interval of three to 18 months, and five of these showed changes in the image including appearance of a new perfusion defect in one patient and improvement of perfusion defects in four. These changes of the myocardial image were correlated well with coronary angiographic findings obtained within a few days of the isotope studies. It was noted that the changes of the myocardial image were more frequently observed at relatively recent period recovered from Kawasaki disease. Exercise myocardial imaging using a bicycle ergometer was performed in eight children with coronary arterial lesions. In three an evidence of improvement of the myocardial perfusion was noted immediately after exercise as well as on the delayed image. In one patient, a decrease of the perfusion in the apex and inferior wall was noted immediately after exercise. On the observed image, image of the apex improved but that of the inferior wall remained hypoperfused. Thus thallium-201 myocardial imaging was considered to permit the best noninvasive documentation imaging was found to be useful in differentiating the viable from nonviable myocardium. It was to be emphasized that quantitative evaluation by computer-assisted analysis was particularly valuable in detecting small areas and in a comparison of the myocardial images. (author)

  12. Do episodes of anger trigger myocardial infarction?

    DEFF Research Database (Denmark)

    Möller, J; Hallqvist, J; Diderichsen, Finn

    1999-01-01

    Our objectives were to study anger as a trigger of acute myocardial infarction (MI) and to explore potential effect modification by usual behavioral patterns related to hostility.......Our objectives were to study anger as a trigger of acute myocardial infarction (MI) and to explore potential effect modification by usual behavioral patterns related to hostility....

  13. The end of the unique myocardial band

    DEFF Research Database (Denmark)

    MacIver, David H; Partridge, John B; Agger, Peter

    2018-01-01

    Two of the leading concepts of mural ventricular architecture are the unique myocardial band and the myocardial mesh model. We have described, in an accompanying article published in this journal, how the anatomical, histological and high-resolution computed tomographic studies strongly favour...

  14. ANGIOTENSIN II AND MYOCARDIAL INFARCTION

    Directory of Open Access Journals (Sweden)

    O. P. Shevchenko

    2008-01-01

    Full Text Available The role of angiotensin II in pathogenesis of cardiovascular diseases is discussed. Angiotensin II participates in development of acute myocardial infarction (MI in patients with atherosclerosis. It contributes to inflammation of vessel intimae, oxidative stress, cells apoptosis, matrix remodeling, has pro-thrombosis action, promotes MI expansion and post-MI remodeling. Angiotensin converting enzyme (ACE inhibitors reduce mortality and improve prognosis of patients with acute MI. In patients with ischemic heart disease including patients after MI ACE inhibitors reduce mortality, risk of repeated MI as well as improve quality of life.

  15. Neuromodulation therapy does not influence blood flow distribution or left-ventricular dynamics during acute myocardial ischemia.

    Science.gov (United States)

    Kingma, J G; Linderoth, B; Ardell, J L; Armour, J A; DeJongste, M J; Foreman, R D

    2001-08-13

    Electrical stimulation of the dorsal aspect of the upper thoracic spinal cord is used increasingly to treat patients with angina pectoris refractory to conventional therapeutic strategies. The purpose of this study was to determine whether spinal cord stimulation (SCS) in dogs affects regional myocardial blood flow and left-ventricular (LV) function before and during transient obstruction of the left anterior descending coronary artery (LAD). In anesthetized dogs, regional myocardial blood flow distribution was determined using radiolabeled microspheres and left-ventricular function was measured by impedance-derived pressure-volume loops. SCS was accomplished by stimulating the dorsal T1-T2 segments of the spinal cord using epidural bipolar electrodes at 90% of motor threshold (MT) (50 Hz, 0.2-ms duration). Effects of 5-min SCS were assessed under basal conditions and during 4-min occlusion of the LAD. SCS alone evoked no change in regional myocardial blood flow or cardiovascular indices. Transient LAD occlusion significantly diminished blood flow within ischemic, but not in non-ischemic myocardial tissue. Left ventricular pressure-volume loops were shifted rightward during LAD occlusion. Cardiac indices were altered similarly during LAD occlusion and concurrent SCS. SCS does not influence the distribution of blood flow within the non-ischemic or ischemic myocardium. Nor does it modify LV pressure-volume dynamics in the anesthetized experimental preparation.

  16. Transient Faults in Computer Systems

    Science.gov (United States)

    Masson, Gerald M.

    1993-01-01

    A powerful technique particularly appropriate for the detection of errors caused by transient faults in computer systems was developed. The technique can be implemented in either software or hardware; the research conducted thus far primarily considered software implementations. The error detection technique developed has the distinct advantage of having provably complete coverage of all errors caused by transient faults that affect the output produced by the execution of a program. In other words, the technique does not have to be tuned to a particular error model to enhance error coverage. Also, the correctness of the technique can be formally verified. The technique uses time and software redundancy. The foundation for an effective, low-overhead, software-based certification trail approach to real-time error detection resulting from transient fault phenomena was developed.

  17. Cohabitation Duration and Transient Domesticity.

    Science.gov (United States)

    Golub, Andrew; Reid, Megan; Strickler, Jennifer; Dunlap, Eloise

    2013-01-01

    Research finds that many impoverished urban Black adults engage in a pattern of partnering and family formation involving a succession of short cohabitations yielding children, a paradigm referred to as transient domesticity. Researchers have identified socioeconomic status, cultural adaptations, and urbanicity as explanations for aspects of this pattern. We used longitudinal data from the 2001 Survey of Income and Program Participation to analyze variation in cohabitation and marriage duration by race/ethnicity, income, and urban residence. Proportional hazards regression indicated that separation risk is greater among couples that are cohabiting, below 200% of the federal poverty line, and Black but is not greater among urban dwellers. This provides empirical demographic evidence to support the emerging theory of transient domesticity and suggests that both socioeconomic status and race explain this pattern. We discuss the implications of these findings for understanding transient domesticity and make recommendations for using the Survey of Income and Program Participation to further study this family formation paradigm.

  18. Ventricular and myocardial scintiscanning: Methodical fundamentals

    International Nuclear Information System (INIS)

    Standke, R.; Hoer, G.; Maul, F.D.

    1984-01-01

    Nuclear cardiology is concerned with non invasive procedures to quantitate global and regional left ventricular function (Radionuclide ventriculography), also the imaging of vitally perfused myocardium (Myocardial scintigraphy) is achieved. A gammacamera and a minicomputer are necessary. Radionuclide ventriculography enables the analysis of global and regional time dependent left ventricular volume curves and hence the evaluation of contraction and contractility of the heart muscle. The basis is a sequence of scans covering an average heartcycle. This sequence may be produced either by first pass or equilibrium technique. Myocardial scintigraphy at rest images vital myocardium, scans immediately after exercise represent the interference of myocardial perfusion and muscle mass. The regional difference (Redistribution) between normalized exercise- and rest scans provide quantitative parameters to detect impairment of exercise-induced myocardial perfusion anomalies. The procedures of sectorial analysis of left ventricular function and myocardial perfusion are presented. (orig.) [de

  19. Explosive and Radio-Selected Transients: Transient Astronomy with ...

    Indian Academy of Sciences (India)

    Therefore, multiwaveband observational efforts with wide fields of view will be the key to progress of transients astronomy from the middle 2020s offering unprecedented deep images and high spatial and spectral resolutions. Radio observations of Gamma Ray Bursts (GRBs) with SKA will uncover not only much fainter ...

  20. Transient analysis of multicavity klystrons

    International Nuclear Information System (INIS)

    Lavine, T.L.; Miller, R.H.; Morton, P.L.; Ruth, R.D.

    1988-09-01

    We describe a model for analytic analysis of transients in multicavity klystron output power and phase. Cavities are modeled as resonant circuits, while bunching of the beam is modeled using linear space-charge wave theory. Our analysis has been implemented in a computer program which we use in designing multicavity klystrons with stable output power and phase. We present as examples transient analysis of a relativistic klystron using a magnetic pulse compression modulator, and of a conventional klystron designed to use phase shifting techniques for RF pulse compression. 4 refs., 4 figs

  1. Dynamic myocardial scintigraphy with 123I-labelled free fatty acids

    International Nuclear Information System (INIS)

    Wall, E.E. van der.

    1981-01-01

    In this thesis, long-chain radioiodinated free fatty acids ( 123 I-FFA), 16-iodo- 123 I-cis-Δ 9 -hexadecenoic acid ( 123 I-HA) and 17-iodo- 123 I-heptade-canoic acid ( 123 I-Hsup(o)A), were employed for myocardial scintigraphy in patients with coronary artery disease. The results indicate that clearance of 123 I-FFA from the myocardium is dependent on the nature of ischemic injury. Clearance is delayed if the injury is reversible and accelerated in case of irreversible ischemia. Mechanisms responsible for divergent behaviour of FFA in patients with acute myocardial infarction versus patients with angina pectoris are purely speculative. This differential clearance from normally perfused, transiently ischemic and infarcted myocardium has practical application. The test provides a means to assess the nature of ischemic injury rapidly. These findings may have major consequences for logical management of patients presenting with chest pain and suspected coronary artery disease. (Auth.)

  2. Risk factors for acute myocardial infarction during the postoperative period of myocardial revascularization

    Directory of Open Access Journals (Sweden)

    José Ribamar Costa Jr.

    2003-03-01

    Full Text Available OBJECTIVE: To identify risk factors for acute myocardial infarction during the postoperative period after myocardial revascularization. METHODS: This was a case-control study paired for sex, age, number, type of graft used, coronary endarterectomy, type of myocardial protection, and use of extracorporeal circulation. We assessed 178 patients (89 patients in each group undergoing myocardial revascularization, and the following variables were considered: dyslipidemia, systemic hypertension, smoking, diabetes mellitus, previous myocardial revascularization surgery, previous coronary angioplasty, and acute myocardial infarction. RESULTS: Baseline clinical characteristics did not differ in the groups, except for previous myocardial revascularization surgery, prevalent in the case group (34 patients vs. 12 patients; p = 0.0002. This was the only independent predictor of risk for acute myocardial infarction in the postoperative period, based on a multivariate logistic regression analysis (p=0.0001. Mortality and the time of hospital stay of the case group were significantly higher (19.1% vs. 1.1%; p<0.001 and 15.7 days vs. 10.6 days; p<0.05 respectively than those of the control. CONCLUSION: Only previous myocardial revascularization was an independent predictor of acute myocardial infarction in the postoperative period, based on multivariate logistic regression analysis.

  3. Three-dimension structure of ventricular myocardial fibers after myocardial infarction

    Directory of Open Access Journals (Sweden)

    Li Libin

    2010-11-01

    Full Text Available Abstract Background To explore the pathological changes of three-dimension structure of ventricular myocardial fibers after anterior myocardial infarction in dog heart. Methods Fourteen acute anterior myocardial infarction models were made from healthy dogs (mean weight 17.6 ± 2.5 kg. Six out of 14 dogs with old myocardial infarction were sacrificed, and their hearts were harvested after they survived the acute anterior myocardial infarction for 3 months. Each heart was dissected into ventricular myocardial band (VMB, morphological characters in infarction region were observed, and infarct size percents in descending segment and ascending segment were calculated. Results Six dog hearts were successfully dissected into VMB. Uncorresponding damages in myocardial fibers of descending segment and ascending segment were found in apical circle in anterior wall infarction. Infarct size percent in the ascending segment was significantly larger than that in the descending segment (23.36 ± 3.15 (SD vs 30.69 ± 2.40%, P = 0.0033; the long axis of infarction area was perpendicular to the orientation of myocardial fibers in ascending segment; however, the long axis of the infarction area was parallel with the orientation of myocardial fibers in descending segment. Conclusions We found that damages were different in both morphology and size in ascending segment and descending segment in heart with myocardial infarction. This may provide an important insight for us to understand the mechanism of heart failure following coronary artery diseases.

  4. Direct Evidence that Myocardial Insulin Resistance following Myocardial Ischemia Contributes to Post-Ischemic Heart Failure

    Science.gov (United States)

    Fu, Feng; Zhao, Kun; Li, Jia; Xu, Jie; Zhang, Yuan; Liu, Chengfeng; Yang, Weidong; Gao, Chao; Li, Jun; Zhang, Haifeng; Li, Yan; Cui, Qin; Wang, Haichang; Tao, Ling; Wang, Jing; Quon, Michael J; Gao, Feng

    2015-01-01

    A close link between heart failure (HF) and systemic insulin resistance has been well documented, whereas myocardial insulin resistance and its association with HF are inadequately investigated. This study aims to determine the role of myocardial insulin resistance in ischemic HF and its underlying mechanisms. Male Sprague-Dawley rats subjected to myocardial infarction (MI) developed progressive left ventricular dilation with dysfunction and HF at 4 wk post-MI. Of note, myocardial insulin sensitivity was decreased as early as 1 wk after MI, which was accompanied by increased production of myocardial TNF-α. Overexpression of TNF-α in heart mimicked impaired insulin signaling and cardiac dysfunction leading to HF observed after MI. Treatment of rats with a specific TNF-α inhibitor improved myocardial insulin signaling post-MI. Insulin treatment given immediately following MI suppressed myocardial TNF-α production and improved cardiac insulin sensitivity and opposed cardiac dysfunction/remodeling. Moreover, tamoxifen-induced cardiomyocyte-specific insulin receptor knockout mice exhibited aggravated post-ischemic ventricular remodeling and dysfunction compared with controls. In conclusion, MI induces myocardial insulin resistance (without systemic insulin resistance) mediated partly by ischemia-induced myocardial TNF-α overproduction and promotes the development of HF. Our findings underscore the direct and essential role of myocardial insulin signaling in protection against post-ischemic HF. PMID:26659007

  5. Role of mechanistic target of rapamycin (mTOR) in renal function and ischaemia-reperfusion induced kidney injury.

    Science.gov (United States)

    Alshaman, Reem; Truong, Luan; Oyekan, Adebayo

    2016-11-01

    Despite the presence of many studies on the role of mechanistic target of rapamycin (mTOR) in cardiorenal tissues, the definitive role of mTOR in the pathogenesis of renal injury subsequent to ischaemia-reperfusion (IR) remains unclear. The aims of the current study were to characterize the role of mTOR in normal kidney function and to investigate the role of mTOR activation in IR-induced kidney injury. In euvolemic anaesthetized rats, treatment with the mTOR inhibitor rapamycin increased blood pressure (121 ± 2 to 144 ± 3 mmHg; Pkidney injury molecule-1 (KIM-1) expression, and rapamycin treatment further increased KIM-1 expression. Clenbuterol exacerbated protein excretion (13 ± 2 to 26 ± 4 mg/day; Pkidney injury in IR rats that was worsened by rapamycin treatment but attenuated by clenbuterol treatment. Thus, mTOR signalling is crucial for normal kidney function and protecting the kidney against IR injury through autophagy suppression. © 2016 John Wiley & Sons Australia, Ltd.

  6. Organ transplantation in Switzerland: impact of the new transplant law on cold ischaemia time and organ transports.

    Science.gov (United States)

    Uehlinger, Nadine B; Beyeler, Franziska; Weiss, Julius; Marti, Hans-Peter; Immer, Franz F

    2010-04-17

    On 1 July 2007 a new transplant law came into force in Switzerland. The principal item of this new law is the change from centre-oriented allocation to patient-oriented national allocation of organs. The aim of the present study is to assess the impact on cold ischaemia time (CIT) and transport requirements. From 1 July 2006 to 30 June 2008 168 brain-dead donors were registered by Swisstransplant in Switzerland. Donors have been analysed in a retrospective cohort study design. Donor characteristics, transportation requirements and CIT were assessed from the Necroreport. 74 donors (44%) were allocated in the period before the introduction of the new law (period A) and 94 donors (56%) after the new law. Donor characteristics were similar. In period A, 114 organs (37.9%) were allocated within the procurement centre, compared to 54 organs (15.5%) in period B. Transport time for liver and kidney was remarkably longer in period B. Overall, CITs remained largely stable except for a significant increase of nearly 115 minutes in the liver graft median CIT (p transplant law clearly entails an increase in the frequency of organ transports. Overall CIT is not affected. However, liver transplantation is afflicted by an increase in transports and CIT. This may affect mid-term outcome and should therefore be followed closely.

  7. The Impact of Obstructive Sleep Apnoea and Nasal Continuous Positive Airway Pressure on Circulating Ischaemia-Modified Albumin Concentrations

    Directory of Open Access Journals (Sweden)

    Firat Uygur

    2016-01-01

    Full Text Available The aim of the present study was to evaluate the impact of obstructive sleep apnoea syndrome (OSAS and the effects of nasal continuous positive airway pressure (CPAP on circulating ischaemia-modified albumin (IMA concentrations. The study included 97 newly diagnosed OSAS patients and 30 nonapnoeic controls. Blood samples were obtained in the morning after polysomnography. After 3 months of CPAP treatment, 31 patients with moderate-severe OSAS were reassessed for serum IMA concentrations. Significantly higher serum IMA concentrations were measured in the OSAS group than in the control group [0.518±0.091 absorbance units (ABSU, 0.415±0.068 ABSU, P<0.001]. Serum IMA concentrations correlated significantly with the apnoea-hypopnoea index, mean SaO2, desaturation index, and C-reactive protein concentrations. Multiple logistic regression analyses showed that OSAS increased the serum IMA concentration independent of age, sex, body mass index, smoking habit, and cardiovascular disease. After 3 months of treatment with CPAP, OSAS patients had significantly lower serum IMA concentrations (0.555±0.062 ABSU to 0.431±0.063 ABSU, P<0.001. The results showed that OSAS is associated with elevated concentrations of IMA, which can be reversed by effective CPAP treatment.

  8. The protective effect of resveratrols on ischaemia-reperfusion injuries of rat hearts is correlated with antioxidant efficacy

    Science.gov (United States)

    Hung, Li-Man; Su, Ming-Jai; Chu, Wing-Keung; Chiao, Chin-Wei; Chan, Wan-Fen; Chen, Jan-Kan

    2002-01-01

    Dietary antioxidants are thought to be beneficial in reducing the incidence of coronary heart disease. In this study, we compared resveratrol and analogues on their antioxidation and free radical scavenging activities to their protective effects on ischaemia-reperfusion induced injuries of rat hearts. Astringinin (3,3′,4′,5-tetrahydroxystilbene) was shown to be a more potent inhibitor than other analogues against Cu2+-induced LDL (low-density lipoprotein) oxidation, as measured by the formation of conjugated diene and TBARS (thiobarbituric acid-reactive substance) and by the electrophoretic mobility of the oxidized LDL. Resveratrol (trans-3,4′,5-trihydroxystilbene) and astringinin scavenged the stable free radical DPPH (1,1-diphenyl-2-picryl-hydrazyl) with an IC0.200 of 7.1 and 4.3 μM, respectively. Astringinin has a superoxide anion scavenging activity about 160 fold more potent than resveratrol. After a 30 min global ischemia followed by 2 h reperfusion, astringinin (10 μM) significantly reduced infarct size, superoxide anion production and increased functional recovery of the coronary flow in Langendorff-perfused rat hearts. The result showed there is a positive correlation between the anti-oxidation and cardioprotective activities among these phenolic compounds. Our finding together with the fact that astringinin is more water-soluble than resveratrol suggest that astringinin could potentially be used as an anti-oxidant and cardioprotective agent in biological systems. PMID:11934802

  9. Activation of PI3-kinase/Akt induced small bowel cell apoptosis during laparoscopic ischaemia-reperfusion of swine jejunum.

    Science.gov (United States)

    Puglisi, F; Lacitigniola, L; Loverre, A; Capuano, P; Martines, G; Staffieri, F; Rossi, G; Crovace, A

    2009-01-01

    This study aimed to detect small bowel cell apoptosis by evaluating the nuclear activation of transcription factors, nuclear factor-kappaB (NF-kappaB) and Akt pathways as well as detecting apoptotic cells by TUNEL assay, during ischaemia-reperfusion (I/R) injury by Arterio-Venous Occlusion (AVO) of ajejunal loop in swine, using a laparoscopic procedure. A jejunal loop was isolated and a biopsy sample (T0) obtained. Biopsies were obtained at 30 minutes (T30I) and 60 minutes (T60I) after clamping and again during reperfusion (R), T30R and T60R. Standard H&E stains and immunohistochemical study for infiltrating polymorphonuclear leukocytes and TUNEL assays were performed. The activation of Akt and NF-kappaB in the animal model was evaluated by indirect immunofluorescence and confocal microscopy. Our results confirmed that I/R injury of the jejunum did not only cause epithelial damage, but also activated the molecular pathways triggering an apoptotic reaction (by pro-inflammatory cytokines) and an anti-apoptotic mechanism that can lead to the regeneration of injured tissue.

  10. [sup 123]I-labelled BMIPP fatty acid myocardial scintigraphy in patients with hypertrophic cardiomyopathy: SPECT comparison with stress [sup 201]Tl

    Energy Technology Data Exchange (ETDEWEB)

    Taki, J.; Nakajima, K.; Bunko, H.; Shimizu, M.; Taniguchi, M.; Hisada, K. (Kanazawa Univ. (Japan). School of Medicine)

    1993-03-01

    [sup 123]I-labelled 15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) myocardial single photon emission computed tomography (SPECT) was performed in 17 patients with hypertrophic cardiomyopathy, and was compared with [sup 201]Tl exercise stress myocardial perfusion (SPECT) images. Fourteen patients showed asymmetrical hypertrophy, and three demonstrated apical hypertrophy. SPECT was performed 20 min and 3 h after injection of 111 MBq [sup 123]I-BMIPP at rest. Exercise stress [sup 201]Tl SPECT was performed at 10 min and 3 h after injection and was compared with BMIPP imaging. In 13 patients BMIPP accumulation in the hypertrophied area in the 20 min image was lower that that of 3 h [sup 201]Tl uptake. Interestingly, six patients demonstrated [sup 201]Tl redistribution in the region where the uncoupling of BMIPP uptake at 20 min and [sup 201]Tl accumulation at 3 h after exercise was observed. These findings suggest that impaired fatty acid metabolism or utilization in hypertrophic myocardium and ischaemia or impaired coronary flow reserve may be one of the causes of the abnormality of fatty acid accumulation. (Author).

  11. Preclinical stroke research--advantages and disadvantages of the most common rodent models of focal ischaemia.

    Science.gov (United States)

    Macrae, I M

    2011-10-01

    This review describes the most commonly used rodent models and outcome measures in preclinical stroke research and discusses their strengths and limitations. Most models involve permanent or transient middle cerebral artery occlusion with therapeutic agents tested for their ability to reduce stroke-induced infarcts and improve neurological deficits. Many drugs have demonstrated preclinical efficacy but, other than thrombolytics, which restore blood flow, none have demonstrated efficacy in clinical trials. This failure to translate efficacy from bench to bedside is discussed alongside achievable steps to improve the ability of preclinical research to predict clinical efficacy: (i) Improvements in study quality and reporting. Study design must include randomization, blinding and predefined inclusion/exclusion criteria, and journal editors have the power to ensure statements on these and mortality data are included in preclinical publications. (ii) Negative and neutral studies must be published to enable preclinical meta-analyses and systematic reviews to more accurately predict drug efficacy in man. (iii) Preclinical groups should work within networks and agree on standardized procedures for assessing final infarct and functional outcome. This will improve research quality, timeliness and translational capacity. (iv) Greater uptake and improvements in non-invasive diagnostic imaging to detect and study potentially salvageable penumbral tissue, the target for acute neuroprotection. Drug effects on penumbra lifespan studied serially, followed by assessment of behavioural outcome and infarct within in the same animal group, will increase the power to detect drug efficacy preclinically. Similar progress in detecting drug efficacy clinically will follow from patient recruitment into acute stroke trials based on evidence of remaining penumbra. © 2011 The Author. British Journal of Pharmacology © 2011 The British Pharmacological Society.

  12. Fuel rod behaviour during transients

    International Nuclear Information System (INIS)

    Hughes, H.; Haste, T.J.; Cameron, R.F.; Sinclair, J.E.

    1982-04-01

    The fuel pin performance code SLEUTH, the transient codes FRAP-T5 and TRAFIC and the clad deformation code CANSWEL-2 are described. It is shown how the codes treat gas release, pin cooling, cladding deformation and interaction, gap conductance etc. The materials properties used are indicated. (author)

  13. Charging transient in polyvinyl formal

    Indian Academy of Sciences (India)

    Unknown

    401–406. © Indian Academy of Sciences. 401. Charging transient in polyvinyl formal. P K KHARE*, P L JAIN† and R K PANDEY‡. Department of Postgraduate Studies & Research in Physics & Electronics, Rani Durgavati University,. Jabalpur 482 001, India. †Department of Physics, Government PG College, Damoh 470 ...

  14. Transient interactions between photosynthetic proteins

    NARCIS (Netherlands)

    Hulsker, Rinske

    2008-01-01

    The biological processes that are the basis of all life forms are mediated largely by protein-protein interactions. The protein complexes involved in these interactions can be categorised by their affinity, which results in a range from static to transient complexes. Electron transfer complexes,

  15. Simulation Model of a Transient

    DEFF Research Database (Denmark)

    Jauch, Clemens; Sørensen, Poul; Bak-Jensen, Birgitte

    2005-01-01

    This paper describes the simulation model of a controller that enables an active-stall wind turbine to ride through transient faults. The simulated wind turbine is connected to a simple model of a power system. Certain fault scenarios are specified and the turbine shall be able to sustain operati...

  16. Transient anisotropic magnetic field calculation

    International Nuclear Information System (INIS)

    Jesenik, Marko; Gorican, Viktor; Trlep, Mladen; Hamler, Anton; Stumberger, Bojan

    2006-01-01

    For anisotropic magnetic material, nonlinear magnetic characteristics of the material are described with magnetization curves for different magnetization directions. The paper presents transient finite element calculation of the magnetic field in the anisotropic magnetic material based on the measured magnetization curves for different magnetization directions. For the verification of the calculation method some results of the calculation are compared with the measurement

  17. Transient filament stretching rheometer II

    DEFF Research Database (Denmark)

    Kolte, Mette Irene; Rasmussen, Henrik K.; Hassager, Ole

    1997-01-01

    The Lagrangian sspecification is used to simulate the transient stretching filament rheometer. Simulations are performed for dilute PIB-solutions modeled as a four mode Oldroyd-B fluid and a semidilute PIB-solution modeled as a non-linear single integral equation. The simulations are compared...

  18. Safety of and tolerance to adenosine infusion for myocardial perfusion single-photon emission computed tomography in a Japanese population.

    Science.gov (United States)

    Hatanaka, Kunihiko; Doi, Masayuki; Hirohata, Satoshi; Kamikawa, Shigeshi; Kaji, Yoko; Katoh, Tsutomu; Kusachi, Shozo; Ninomiya, Yoshifumi; Ohe, Tohru

    2007-06-01

    Adenosine has been available for use in myocardial perfusion single-photon emission computed tomography (SPECT) in Japan since 2005. The purpose of this study was to evaluate the safety of and tolerance to thallium-201 myocardial perfusion SPECT with intravenous adenosine infusion in Japanese patients with suspected coronary artery disease. Two hundred and six consecutive patients who underwent an adenosine infusion (120 mug . kg(-1) . min(-1)) SPECT at Sumitomo Besshi Hospital (Niihama, Japan) were investigated. The effects of adenosine infusion were monitored for each patient. A coronary angiography was performed in 81 patients. Adenosine infusion significantly decreased blood pressure and increased heart rate. Adverse reactions were observed in 161 patients (78.2%). Most reactions were transient, disappearing soon after the termination of adenosine infusion. No serious adverse reactions, such as acute myocardial infarction or death, occurred. Adenosine infusion was terminated in 3 patients (1.5%) because of near syncope or sustained 2:1 atrioventricular block. Electrocardiographic changes occurred in 15 patients (7.3%). Self-assessed scoring after SPECT showed that the patients were very tolerant (74.6% of 177 patients) of adenosine infusion myocardial SPECT. The sensitivity and specificity were 75.0% and 69.7%, respectively. Adenosine infusion myocardial SPECT is safe and well tolerated in the Japanese population, despite the frequent occurrence of minor adverse reactions.

  19. Comparison of the myocardial blood flow response to regadenoson and dipyridamole: a quantitative analysis in patients referred for clinical 82Rb myocardial perfusion PET

    International Nuclear Information System (INIS)

    Goudarzi, Behnaz; Fukushima, Kenji; Bravo, Paco; Merrill, Jennifer; Bengel, Frank M.

    2011-01-01

    Regadenoson is a novel selective A 2A adenosine receptor agonist, which is administered as an intravenous bolus at a fixed dose. It is currently not clear if the absolute flow increase in response to this fixed dose is a function of distribution volume in individual patients or if it is generally comparable to the previous standard agents dipyridamole or adenosine, which are dosed based on weight. We used quantitative analysis of clinical 82 Rb PET/CT studies to obtain further insights. A total of 104 subjects with normal clinical rest/stress 82 Rb perfusion PET/CT were included in a retrospective analysis. To rule out confounding factors, none had evidence of prior cardiac disease, ischaemia or infarction, cardiomyopathy, diabetes with insulin use, calcium score >400, renal disease or other significant systemic disease. A group of 52 patients stressed with regadenoson were compared with a group of 52 patients stressed with dipyridamole before regadenoson became available. The groups were matched for clinical characteristics, risk factors and baseline haemodynamics. Myocardial blood flow (MBF) and myocardial flow reserve (MFR) were quantified using a previously validated retention model, after resampling of dynamic studies from list-mode 82 Rb datasets. At rest, heart rate, blood pressure and MBF were comparable between the groups. Regadenoson resulted in a significantly higher heart rate (34 ± 14 vs. 23 ± 10 beats per minute increase from baseline; p < 0.01) and rate-pressure product. Patients in the regadenoson group reported less severe symptoms and required less aminophylline. Stress MBF and MFR were not different between the groups (2.2 ± 0.6 vs. 2.1 ± 0.6 ml/min/g, p = 0.39, and 2.9 ± 0.8 vs. 2.8 ± 0.7, p = 0.31, respectively). In the regadenoson group, there was no correlation between stress flow or MFR and body weight or BMI. Despite its administration at a fixed dose, regadenoson results in an absolute increase in MBF which is comparable to that

  20. Myocardial perfusion imaging with dual energy CT

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, SMG-SNU Boramae Medical Center, Seoul (Korea, Republic of); De Cecco, Carlo N. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncology and Pathology, University of Rome “Sapienza”, Rome (Italy); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Spandorfer, Adam; Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States)

    2016-10-15

    Highlights: • Stress dual-energy sCTMPI offers the possibility to directly detect the presence of myocardial perfusion defects. • Stress dual-energy sCTMPI allows differentiating between reversible and fixed myocardial perfusion defects. • The combination of coronary CT angiography and dual-energy sCTMPI can improve the ability of CT to detect hemodynamically relevant coronary artery disease. - Abstract: Dual-energy CT (DECT) enables simultaneous use of two different tube voltages, thus different x-ray absorption characteristics are acquired in the same anatomic location with two different X-ray spectra. The various DECT techniques allow material decomposition and mapping of the iodine distribution within the myocardium. Static dual-energy myocardial perfusion imaging (sCTMPI) using pharmacological stress agents demonstrate myocardial ischemia by single snapshot images of myocardial iodine distribution. sCTMPI gives incremental values to coronary artery stenosis detected on coronary CT angiography (CCTA) by showing consequent reversible or fixed myocardial perfusion defects. The comprehensive acquisition of CCTA and sCTMPI offers extensive morphological and functional evaluation of coronary artery disease. Recent studies have revealed that dual-energy sCTMPI shows promising diagnostic accuracy for the detection of hemodynamically significant coronary artery disease compared to single-photon emission computed tomography, invasive coronary angiography, and cardiac MRI. The aim of this review is to present currently available DECT techniques for static myocardial perfusion imaging and recent clinical applications and ongoing investigations.

  1. [Transient amnesia in the elderly].

    Science.gov (United States)

    Sellal, François

    2006-03-01

    The two main aetiologies of transient amnesia in the elderly are idiopathic transient global amnesia (TGA) and iatrogenic or toxic amnesia. Vascular and epileptic amnesia are less common. According to the literature, transient psychogenic amnesia, which is a frequent cause of amnesia at age 30 to 50, is very rare in the elderly. TGA is the prototypical picture of transient amnesia. It occurs more often after age 50, with no identified cause, even if some authors accept emotional stress or minor head trauma as occasional precipitants. The mechanism of TGA remains a matter of discussion. It may be the consequence of a spreading depression similar to that described in migraine with aura, but other arguments support an ischemic mechanism. Iatrogenic amnesias are mainly caused by benzodiazepines (BZs) or anticholinergics. The former may occur in a non-anxious subject, who is not a usual consumer of BZ and takes a single dose. The latter are more often due to a hypersensitivity to anticholinergic drugs, in particular in patients presenting with a covert, incipient Alzheimer's disease. A vascular origin must be considered when amnesia is accompanied by other neurological symptoms, and when the regression of the amnesic disorder is slow, lasting several days. It results from lesions involving various mechanisms and locations, mainly subcortical. Partial seizures, most often mesio-temporal, more rarely frontal, may be the cause of transient amnesia in the elderly, in the absence of a past history of epilepsy. The red flag supportive of an epileptic origin is the repetition of stereotyped amnesic episodes. EEG demonstration of seizures may be difficult and the response to antiepileptic drugs effective on partial seizures is usually good.

  2. Constitutive cardiac overexpression of sarcoplasmic/endoplasmic reticulum Ca2+-ATPase delays myocardial failure after myocardial infarction in rats at a cost of increased acute arrhythmias.

    Science.gov (United States)

    Chen, Ying; Escoubet, Brigitte; Prunier, Fabrice; Amour, Julien; Simonides, Warner S; Vivien, Benoît; Lenoir, Christophe; Heimburger, Michèle; Choqueux, Christine; Gellen, Barnabas; Riou, Bruno; Michel, Jean-Baptiste; Franz, Wolfgang M; Mercadier, Jean-Jacques

    2004-04-20

    Heart failure often complicates myocardial infarction (MI), and sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA2a) is underexpressed in the failing myocardium. We examined the effect of preexisting cardiac SERCA2a protein overexpression on rat survival and left ventricular (LV) remodeling after MI. Baseline myocardial SERCA2a expression was 37% higher in transgenic (TG) rats than in their wild-type (WT) controls, consistent with enhanced myocardial function. The mortality rate of TG rats during the 24 hours after surgical MI was higher than that of WT rats (71% versus 35%, P<0.001), associated with a higher frequency of ventricular arrhythmias, and was normalized by lidocaine treatment. The increased acute-phase mortality in TG rats was not accompanied by increased 6-month mortality. Function of the noninfarcted myocardium, as assessed by tissue Doppler imaging, was higher in TG rats than in WT rats for up to 1 month after MI, a beneficial effect no longer observed at 3 months. LV remodeling and global function were similar in TG and WT rats. No difference in papillary muscle function was found at 6 months. Constitutive cardiac SERCA2a overexpression has a transient beneficial effect on remote myocardium function in rat MI, with no improvement in LV global function or prevention of LV remodeling and failure. This benefit is associated with a higher risk of acute mortality, which is prevented by lidocaine treatment.

  3. Persistent phenotypic shift in cardiac fibroblasts: impact of transient renin angiotensin system inhibition.

    Science.gov (United States)

    Hale, Taben M

    2016-04-01

    Fibrotic cardiac remodeling ultimately leads to heart failure - a debilitating and costly condition. Select antihypertensive agents have been effective in reducing or slowing the development of cardiac fibrosis. Moreover, some experimental studies have shown that the reduction in fibrosis induced by these agents persists long after stopping treatment. What has not been as well investigated is whether this transient treatment results in a protection against future fibrotic cardiac remodeling. In the present review, previously published studies are re-examined to assess whether the relative percent increase in collagen deposition over an off-treatment period is attenuated, relative to control, following transient antihypertensive treatment in young or adult rats. Present findings suggest that transient inhibition of the renin angiotensin system (RAS) not only produces a sustained reduction in cardiac fibrosis, but also results in a degree of protection against future collagen deposition. In addition, prior transient RAS inhibition appears to alter the cardiac fibroblast phenotype such that these cells show a muted response to myocardial injury - namely reduced proliferation, chemokine release, and collagen deposition. This review puts forth several potential mechanisms underlying this long-term cardiac protection that is afforded by transient RAS inhibition. Specifically, fibroblast phenotypic change, cardiac fibroblast apoptosis, sustained suppression of the RAS, persistent reduction in left ventricular hypertrophy, and persistent reduction in arterial pressure are each discussed. Identifying the mechanisms ultimately responsible for this change in cardiac fibroblast response to injury, hypertension, and aging may reveal novel targets for therapy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Prolonged caloric restriction in obese patients with type 2 diabetes mellitus decreases myocardial triglyceride content and improves myocardial function

    NARCIS (Netherlands)

    Hammer, Sebastiaan; Snel, Marieke; Lamb, Hildo J.; Jazet, Ingrid M.; van der Meer, Rutger W.; Pijl, Hanno; Meinders, Edo A.; Romijn, Johannes A.; de Roos, Albert; Smit, Johannes W. A.

    2008-01-01

    This study sought to assess the effects of prolonged caloric restriction in obese patients with type 2 diabetes mellitus (T2DM) on myocardial triglyceride (TG) content and myocardial function. Myocardial TG content is increased in patients with T2DM and may reflect altered myocardial function. It is

  5. Latent myocardial damage after cardiopulmonary resuscitation in a teenager without prior cardiac disease

    Directory of Open Access Journals (Sweden)

    A. S. Sharykin

    2014-01-01

    Full Text Available Cardiopulmonary resuscitation is an integral part of intensive care in children and adolescents with a number of diseases, most commonly with congenital heart disease, critical cardiac arrhythmias, or severe traumas. This procedure can cause a number of complications, most of them are still completely unstudied, and many of them are associated with the underlying disease. We have a unique case report of a 14-year-old boy without any cardiac disease, who underwent extensive resuscitative measures, including closed-chest massage, tracheal intubation with mechanical ventilation, as well as a few electrical defibrillations with transient myocardial injury. 

  6. Prognostic significance of stress myocardial gated SPECT among Japanese patients referred for coronary angiography: A study of data from the J-ACCESS database

    International Nuclear Information System (INIS)

    Momose, Mitsuru; Nakajima, Kenichi; Nishimura, Tsunehiko

    2009-01-01

    The J-ACCESS [Japanese investigation of prognosis based on gated single photon emission computed tomography (SPECT)] study found that quantitative gated myocardial SPECT (QGS) is valuable for predicting the prognosis of Japanese patients with known or suspected ischaemic heart disease. The present study evaluates the incremental prognostic value of myocardial perfusion imaging (MPI) with QGS among patients referred for coronary angiography (CAG). Among 4,031 Japanese patients registered at 117 hospitals for the J-ACCESS study, we selected 1,011 who underwent CAG within 3 months before or after MPI with QGS. Summed stress, rest and difference scores (SSS, SRS and SDS) were generated from myocardial perfusion images using a 20-segment scoring system. Myocardial ischaemia was judged visually. End-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) were determined by QGS. Numbers of diseased (> 75% stenosis) coronary vessels (CDV) were assessed by CAG. All patients were followed up for 3 years to determine cardiac events (CE) including cardiac death, non-fatal myocardial infarction and severe heart failure. Univariate and multivariate analyses of prognostic ability included age, cardiac risk factors (hypertension, hyperlipidaemia, diabetes mellitus and prior myocardial infarction), angiographic findings and the QGS parameters as independent variables. Cardiac events occurred more frequently with increasing numbers of coronary vessel lesions (p=0.0016). Cox univariate analysis revealed that diabetes, CDV, SSS, SDS, EDV, ESV and EF were significant predictors (Wald χ 2 =5.99, 12.9, 8.39, 9.11, 35.5, 42.1 and 31.1, respectively), whereas multivariate analysis selected only ESV and SDS as significant predictors (Wald χ 2 =36.4, 8.4; p = 0.0038, p < 0.001). MPI with QGS, especially with gated functional data, has incremental prognostic value in addition to angiographic findings. MPI with QGS findings predominantly contribute to the prediction of

  7. Myocardial infarction in the young

    Directory of Open Access Journals (Sweden)

    Cengel A

    2009-01-01

    Full Text Available An increasing number of patients under 40 years of age are being hospitalized with the diagnosis of acute myocardial infarction. This is partly due to the increased prevalance of risk factors for atherosclerosis in the younger age group; especially increased incidence of impaired fasting glucose, high triglyceride, low high-density lipoprotein levels and increased waist to hip ratio. However, non-atherosclerotic coronary artery disease or hypercoagulability should also be investigated or at least suspected in the younger patients. The pathophysiology of different clinical conditions and disease states which cause acute coronary syndromes in the young patients are reviewed, and the diagnostic modalities and therapatic options for these conditions are briefly discussed by searching for "premature atherosclerosis", "hypercoagulable states", "risk factors for atherosclerosis in youth", "novel risk factors for atherosclerosis", "non-atherosclerotic coronary artery diseases" in PubMed.

  8. Transient myocardial ischemia after abrupt withdrawal of antianginal therapy in chronic stable angina

    DEFF Research Database (Denmark)

    Egstrup, K

    1988-01-01

    In 47 patients with chronic stable angina and proven coronary artery disease, abrupt withdrawal of beta-adrenoceptor blocking agents either as monotherapy or in combination with calcium antagonists (group 1, n = 25) was compared with abrupt withdrawal of calcium antagonist monotherapy (group 2, n...

  9. Sequential myocardial scintigraphy with technetium-99m stannous pyrophosphate following myocardial infarction

    International Nuclear Information System (INIS)

    Malin, F.R.; Rollo, F.D.; Gertz, E.W.

    1978-01-01

    Studies have shown that technetium-99m stannous pyrophosphate (Tc-PPi) is effective for the detection and imaging of acute myocardial infarction. Positive Tc-PPi myocardial scintigrams, however, have been reported in patients with other forms of heart disease and no evidence of recent myocardial infarction. To help define the usefulness of this test, we undertook a prospective study to ascertain when Tc-PPi myocardial scintigrams return to normal after myocardial infarction. Twenty patients with acute myocardial infarction were followed with Tc-PPi scintigrams at 1 and 2 wk, and 1, 2, 3, 6, and 9 mo after infarction. The serial scintigrams revealed that (a) 15 of 18 scintigrams were positive within the first week after infarction, (b) the number of markedly positive scintigrams decreased promptly after the first week, and (c) some scintigrams (11 of 18 at 1 mo, and 3 of 18 at 9 mo) remained positive throughout the study. The possible explanations for persistently positive scintigrams are discussed. Persistently positive scintigrams may hinder the usefulness of Tc-PPi myocardial scintigraphy for the diagnosis of acute myocardial infarction in patients who have had a myocardial infarction within the previous 9 mo

  10. Nuclear power plant transients: where are we

    International Nuclear Information System (INIS)

    Majumdar, D.

    1984-05-01

    This document is in part a postconference review and summary of the American Nuclear Society sponsored Anticipated and Abnormal Plant Transients in Light Water Reactors Conference held in Jackson, Wyoming, September 26-29, 1983, and in part a reflection upon the issues of plant transients and their impact on the viability of nuclear power. This document discusses state-of-the-art knowledge, deficiencies, and future directions in the plant transients area as seen through this conference. It describes briefly what was reported in this conference, emphasizes areas where it is felt there is confidence in the nuclear industry, and also discusses where the experts did not have a consensus. Areas covered in the document include major issues in operational transients, transient management, transient events experience base, the status of the analytical tools and their capabilities, probabilistic risk assessment applications in operational transients, and human factors impact on plant transients management

  11. Numerical solution of transient viscoelastic flow

    DEFF Research Database (Denmark)

    Hassager, Ole; Rasmussen, Henrik K.; Szabo, Peter

    1996-01-01

    A number of applications of the Lagrangina kinematic specification in the simulation of transient viscoelastic flows are shown.......A number of applications of the Lagrangina kinematic specification in the simulation of transient viscoelastic flows are shown....

  12. Fast thermal transients on valve

    International Nuclear Information System (INIS)

    Ferjancic, M.; Stok, B.; Halilovic, M.; Koc, P.; Mole, N.; Otrin, Z.; Kotar, A.

    2007-01-01

    One of the regulatory body methods to supervise nuclear safety of a nuclear power plant is a review of plant modifications and evaluation of their impact on plant operating experience. The Slovenian Nuclear Safety Administration (SNSA) licensed in April 2003 the use of leak-before-break (LBB) methodology in the Krsko NPP for the primary loop including surge line and connecting pipelines with minimal diameter of 6 inch. The SNSA decision based also on fracture mechanics analyses that include direct pipe failure mechanisms such as water hammer, creep damage, erosion and corrosion, fatigue and environmental conditions over the entire life of the plant. The evaluation of the operating transients pointed out, that presumed loadings, used for the LBB analysis, did not incorporate all the fast thermal transients data. For that purpose the SNSA requested Faculty of Mechanical Engineering (FS) in Ljubljana to perform additional analyses. The results of the analysis shall confirm the validity of the LBB analysis. (author)

  13. Towards traceable transient pressure metrology

    Science.gov (United States)

    Hanson, Edward; Olson, Douglas A.; Liu, Haijun; Ahmed, Zeeshan; Douglass, Kevin O.

    2018-04-01

    We describe our progress in developing the infrastructure for traceable transient measurements of pressure. Towards that end, we have built and characterized a dual diaphragm shock tube that allows us to achieve shock amplitude reproducibility of approximately 2.3% for shocks with Mach speeds ranging from 1.26–1.5. In this proof-of-concept study we use our shock tube to characterize the dynamic response of photonic sensors embedded in polydimethylsiloxane (PDMS), a material of choice for soft tissue phantoms. Our results indicate that the PDMS-embedded photonic sensors response to shock evolves over a tens to hundreds of microseconds time scale making it a useful system for studying transient pressures in soft tissue.

  14. Nonlinear Diffusion and Transient Osmosis

    International Nuclear Information System (INIS)

    Igarashi, Akira; Rondoni, Lamberto; Botrugno, Antonio; Pizzi, Marco

    2011-01-01

    We investigate both analytically and numerically the concentration dynamics of a solution in two containers connected by a narrow and short channel, in which diffusion obeys a porous medium equation. We also consider the variation of the pressure in the containers due to the flow of matter in the channel. In particular, we identify a phenomenon, which depends on the transport of matter across nano-porous membranes, which we call ''transient osmosis . We find that nonlinear diffusion of the porous medium equation type allows numerous different osmotic-like phenomena, which are not present in the case of ordinary Fickian diffusion. Experimental results suggest one possible candidate for transiently osmotic processes. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  15. The Pathogenesis of Human Myocardial Infarction

    Science.gov (United States)

    Rona, George

    1966-01-01

    Coronary arteriography, dissection of the coronary arteries and histopathological examination of the heart were carried out in 150 autopsies to study the effect of coronary narrowing and occlusion, of the presence of collaterals, and of coronary artery predominance on the development of myocardial infarction. The thrombosis rate was related to the severity of coronary sclerosis. The development of collaterals was not enhanced by coronary sclerosis and occlusion, and collaterals did not protect the myocardium against reinfarction. Coronary occlusion was regularly demonstrable in recent myocardial infarct cases. The association of atrial and posterior ventricular infarcts was explained by occlusion of their common arterial branch. The interdependence between coronary sclerosis, thrombosis and myocardial infarction in human autopsy material emphasizes the importance of mural coronary artery disease in the genesis of coronary occlusion and myocardial infarction, and it is at variance with statistical data and experimental results. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6 PMID:5924947

  16. [Blood serum lipoprotein spectrum in myocardial infarct].

    Science.gov (United States)

    Efremushkin, G G; Goriacheva, A V; Kolomenskaia, T I; Solomatina, L G; Ovcharenko, R P

    1979-11-01

    The lipoprotein spectrum was studied in polyacrylamide gel and by thin-layer chromatography on silica gel in 236 patients with myocardial infarction in different periods of the disease, in 45 patients with unstable angina pectoris, in 75 healthy persons and in 8 dogs with experimental myocardial infarction. Besides an increase in the concentration of cholesterol and triglycerides and a decrease in the level of diglycerides in blood serum, there is a disturbance in the ratio of phospholipid fractions, mainly in myocardial infarction. The level of pre-beta-lipoproteins was increased in the acute period of myocardial infarction, the level of beta-lipoproteins in the subacute period. Complications and concomitant inflammatory diseases were attended by a higher level of beta-lipoproteins. A connection was noted between the lipoprotein spectrum, predominantly of the pre-beta-fraction, and the ABO phenotype and the season.

  17. Diagnosing Myocardial Contusion after Blunt Chest Trauma

    Directory of Open Access Journals (Sweden)

    Zahra Alborzi

    2016-10-01

    Full Text Available A myocardial contusion refers to a bruise of the cardiac muscle, the severity of which can vary depending on the severity of the injury and when the injury occurs. It is a major cause of rapid death which happens after blunt chest trauma and should be suspected at triage in the emergency department. We demonstrated that suspected myocardial contusion patients who have normal electrocardiograms (ECGs and biomarker tests can be safely discharged. However, if the test results are abnormal, the next steps should be echocardiography and more advanced measures. Diagnosing myocardial contusion is very difficult because of its nonspecific symptoms. If a myocardial contusion happens, cardiogenic shock or arrhythmia must be anticipated, and the patient must be carefully monitored.

  18. The effect of levosimendan on myocardial ischemiareperfusion ...

    African Journals Online (AJOL)

    The effect of levosimendan on myocardial ischemiareperfusion injury in streptozotocin-induced diabetic rats. Hasan Ali Kiraz, Fatih Poyraz, Gulay Kip, Ozlem Erdem, Metin Alkan, Mustafa Arslan, Abdullah Ozer, Volkan Sivgin, Faruk Metin Comu ...

  19. [Stem cell perspectives in myocardial infarctions].

    Science.gov (United States)

    Aceves, José Luis; Archundia, Abel; Díaz, Guillermo; Páez, Araceli; Masso, Felipe; Alvarado, Martha; López, Manuel; Aceves, Rocío; Ixcamparij, Carlos; Puente, Adriana; Vilchis, Rafael; Montaño, Luis Felipe

    2005-01-01

    Myocardial infarction is the leading cause of congestive heart failure and death in industrializated countries. The cellular cardiomyoplasty has emerged as an alternative treatment in the regeneration of infarted myocardial tissue. In animals' models, different cellular lines such as cardiomyocites, skeletal myoblasts, embryonic stem cells and adult mesenchymal stem cells have been used, resulting in an improvement in ventricular function and decrease in amount of infarcted tissue. The first three cells lines have disvantages as they are allogenics and are difficult to obtain. The adult mesenchymal stem cells are autologous and can be obtained throught the aspiration of bone marrow or from peripherical circulation, after stimulating with cytokines (G-CSF). The implantation in humans with recent and old myocardial infarction have shown improvements similar to those shown in animal models. These findings encourage the continued investigation in the mechanism of cellular differentiation and implantation methods in infarcted myocardial tissue.

  20. Quantitative aspects of myocardial perfusion imaging

    International Nuclear Information System (INIS)

    Vogel, R.A.

    1980-01-01

    Myocardial perfusion measurements have traditionally been performed in a quantitative fashion using application of the Sapirstein, Fick, Kety-Schmidt, or compartmental analysis principles. Although global myocardial blood flow measurements have not proven clinically useful, regional determinations have substantially advanced our understanding of and ability to detect myocardial ischemia. With the introduction of thallium-201, such studies have become widely available, although these have generally undergone qualitative evaluation. Using computer-digitized data, several methods for the quantification of myocardial perfusion images have been introduced. These include orthogonal and polar coordinate systems and anatomically oriented region of interest segmentation. Statistical ranges of normal and time-activity analyses have been applied to these data, resulting in objective and reproducible means of data evaluation