Sample records for bradycardia

  1. Bradycardia (United States)

    ... people, particularly for healthy young adults and trained athletes. For these people, bradycardia isn't considered a ... as rheumatic fever or lupus The buildup of iron in organs (hemochromatosis) Medications, including some drugs for ...

  2. Peripartum Cardiomyopathy Presenting as Bradycardia (United States)

    Rose, Carl H.; Tweet, Marysia S.; Hayes, Sharonne N.; Best, Patricia J. M.; Blauwet, Lori A.


    Peripartum cardiomyopathy (PPCM) is a disease that typically affects young otherwise healthy women. As PPCM is associated with significant mortality, timely diagnosis is necessary to ensure appropriate care. To our knowledge, this represents the first reported case of PPCM presenting as symptomatic bradycardia. We describe the patient's clinical presentation and relevant findings and review the potential etiology and ramifications of bradycardia in patients with PPCM.

  3. Peripartum Cardiomyopathy Presenting as Bradycardia

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    Elisabeth Codsi


    Full Text Available Peripartum cardiomyopathy (PPCM is a disease that typically affects young otherwise healthy women. As PPCM is associated with significant mortality, timely diagnosis is necessary to ensure appropriate care. To our knowledge, this represents the first reported case of PPCM presenting as symptomatic bradycardia. We describe the patient’s clinical presentation and relevant findings and review the potential etiology and ramifications of bradycardia in patients with PPCM.

  4. Nodal bradycardia induced by tocainide.


    Mandal, S. K.; Datta, S.K.


    A case of tocainide-induced nodal bradycardia in standard recommended dose is reported. There was no recurrence when the drug was subsequently reintroduced in a reduced dosage. It is suggested that in the elderly, tocainide should be used in a lower dosage than normally recommended.

  5. [The bradycardia-tachycardia syndrome]. (United States)

    Salazar, E; Cerda, G; Pieniak, M


    Disorders of the heart rhythm which consist basically of sinus bradicardia or sinus arrest correspond to a syndrome which has been named the sick sinus syndrome. Within the framework of this syndrome, there is a subgroup of alternating atrial bradycardia with episodes of atrial tachyarrhythmia. Generally known as the bradycardia-tachycardia syndrome, this subgroup is both electrophysiologically interesting and therapeutically challenging. This report is concerned with the experience obtained at the emergency ward and coronary care unit of the Instituto Nacional de Cardiología de México on the diagnosis and management of 8 patients with this syndrome. Various underlying heart conditions were present with predominance of ischemic heart disease. The clinical picture was dependent upon the hypoperfusion of vital organs secondary to the cardial arrhythmia. The most common symptoms were derived from cerebral circulatory deficit and coronary insufficiency. Half of the patients had moderate cardiac failure. All patients had spontaneous and transient loss of sinus function which lasted more than 2,000 msec. in seven. The bradycardia had a rate below 50 beats per minute in all cases except one. The tachyarrhythmias observed were atrial flutter, atrial fibrillation and paroxysmal supraventricular tachycardia. Three of the patients had more than one of these these tachyarrhythmias during the period of study. A discussion is made on the diagnosis of this syndrome by means of atrial pacing and interventions which modify either vagal or sympathetic tone. Considerations are also made on the frequent associated abnormality of the A-V functional tissues. Emphasis is placed on the problems encountered in the management of these patients. It is concluded that, in most cases, a satisfactory result may be obtained by the implantation of a permanent demand pacemaker associated to the administration of antiarrhythmic drugs.

  6. Bradycardia During Targeted Temperature Management

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    Thomsen, Jakob Hartvig; Nielsen, Niklas; Hassager, Christian


    OBJECTIVES: Bradycardia is common during targeted temperature management, likely being a physiologic response to lower body temperature, and has recently been associated with favorable outcome following out-of-hospital cardiac arrest in smaller observational studies. The present study sought...... to confirm this finding in a large multicenter cohort of patients treated with targeted temperature management at 33°C and explore the response to targeted temperature management targeting 36°C. DESIGN: Post hoc analysis of a prospective randomized study. SETTING: Thirty-six ICUs in 10 countries. PATIENTS......: We studied 447 (targeted temperature management = 33°C) and 430 (targeted temperature management = 36°C) comatose out-of-hospital cardiac arrest patients with available heart rate data, randomly assigned in the targeted temperature management trial from 2010 to 2013. INTERVENTIONS: Targeted...

  7. Electrocution induced symptomatic bradycardia necessitating pacemaker implantation



    Electrical or electrocution injury is a common accidental occurrence and mostly workplace related. Fatal arrhythmias, skin injury and sudden death may ensue. However, it is rare for electrocution to result in permanent low rate sinus bradycardia, incompatible with an active lifestyle. The probable mechanisms for this pathological sinus bradycardia are sinus node dysfunction and autonomic dysfunction with vagal predominance. We describe a young patient who suffered a non fatal electrocution wi...

  8. Propranolol induced bradycardia in tetralogy of Fallot.



    When an 18 month old girl who had tetralogy of Fallot and episodes of severe cyanosis with loss of consciousness was treated with propranolol there was some improvement. But when the dose was increased she had further episodes of near syncope. Holter monitoring showed extreme intermittent bradycardia with pauses of up to 2.6 seconds. The episodes of near syncope and the bradycardia resolved after propranolol was stopped. Apparent failure of propranolol treatment may on rare occasions be relat...

  9. [Anorexia with sinus bradycardia: a case report]. (United States)

    Wang, Fang-fang; Xu, Ling; Chen, Bao-xia; Cui, Ming; Zhang, Yuan


    As anorexia patients always go to the psychiatric clinic, little is concerned about the occurrence of sinus bradycardia in these patients for cardiologists and psychiatrists. The aim of this paper is to discuss the relationship between anorexia and sinus bradycardia, and the feature analysis, differential diagnosis and therapeutic principles of this type of sinus bradycardia. We report a case of sinus bradycardia in an anorexia patient with the clinical manifestations, laboratory exams, auxiliary exams, therapeutic methods, and her prognosis, who was admitted to Peking University Third Hospital recently. The patient was a 19-year-old female, who had the manifestation of anorexia. She lost obvious weight in a short time (about 15 kg in 6 months), and her body mass index was 14.8 kg/m(2). The patient felt apparent palpitation, chest depression and short breath, without dizziness, amaurosis or unconsciousness. Vitals on presentation were notable for hypotension, and bradycardia. The initial exam was significant for emaciation, but without lethargy or lower extremity edema. The electrocardiogram showed sinus bradycardia with her heart rate being 32 beats per minute. The laboratory work -up revealed her normal blood routine, electrolytes and liver function. But in her thyroid function test, the free thyroid (FT) hormones 3 was 0.91 ng/L (2.3-4.2 ng/L),and FT4 was 8.2 ng/L (8.9-18.0 ng/L), which were all lower; yet the thyroid stimulating hormone (TSH) was normal 1.48 IU/mL (0.55-4.78 IU/mL). Ultrasound revealed her normal thyroid. Anorexia is an eating disorder characterized by extremely low body weight, fear of gaining weight or distorted perception of body image, and amenorrhea. Anorexia patients who lose weight apparently in short time enhance the excitability of the parasympathetic nerve, and inhibit the sympathetic nerve which lead to the appearance of sinus bradycardia, and functional abnormalities of multiple systems such as hypothyroidism. But this kind of sinus

  10. A metoprolol-terbinafine combination induced bradycardia. (United States)

    Bebawi, Emmanuel; Jouni, Suhail S; Tessier, Andrée-Anne; Frenette, Anne Julie; Brindamour, Dave; Doré, Maxime


    To report a sinus bradycardia induced by metoprolol and terbinafine drug-drug interaction and its management. A 63 year-old Caucasian man on metoprolol 200 mg/day for stable coronary artery disease was prescribed a 90-day course of oral terbinafine 250 mg/day for onychomycosis. On the 49th day of terbinafine therapy, he was brought to the emergency room for a decrease of his global health status, confusion and falls. The electrocardiogram revealed a 37 beats/min sinus bradycardia. A score of 7 on the Naranjo adverse drug reaction probability scale indicates a probable relationship between the patient's sinus bradycardia and the drug interaction between metoprolol and terbinafine. The heart rate ameliorated first with a decrease in the dose of metoprolol. It was subsequently changed to bisoprolol and the heart rate remained normal. By inhibiting the cytochrome P450 2D6, terbinafine had decreased metoprolol's clearance, leading in metoprolol accumulation which has resulted in clinically significant sinus bradycardia.

  11. Severe bradycardia and prolonged hypotension in ciguatera. (United States)

    Chan, Thomas Yan Keung


    Ciguatera results when ciguatoxin-contaminated coral reef fish from tropical or subtropical waters are consumed. The clinical features that present in affected persons are mainly gastrointestinal, neurological, general, and much less commonly, cardiovascular. We report the case of a 50-year-old man who developed the characteristic combination of acute gastrointestinal and neurological symptoms after the consumption of an unidentified coral reef fish head. In addition to those symptoms, he developed dizziness, severe bradycardia (46 bpm) and prolonged hypotension, which required the administration of intravenous atropine and over three days of intravenous fluid replacement with dopamine infusion. Patients with ciguatera can develop severe bradycardia and prolonged hypotension. Physicians should recognise the possible cardiovascular complications of ciguatera and promptly initiate treatment with intravenous atropine, intravenous fluid replacement and inotropic therapy if such complications are observed.

  12. Worsening Bradycardia Following Antithymocyte Globulin Treatment of Severe Aplastic Anemia



    Immunosuppressive regimens, which include antithymocyte globulin (ATG), are widely used for the treatment of severe aplastic anemia (SAA). However, bradycardia has been reported only as a rare side effect of ATG therapy in the manufacturer's product information and, in rare cases, in the adult literature. We present an adolescent with SAA and preexisting bradycardia who underwent immunosuppression therapy with ATG, methylprednisolone, and tacrolimus and developed profound sinus bradycardia wi...

  13. Association between Ophthalmic Timolol and Hospitalisation for Bradycardia



    Introduction. Ophthalmic timolol, a topical nonselective beta-blocker, has the potential to be absorbed systemically which may cause adverse cardiovascular effects. This study was conducted to determine whether initiation of ophthalmic timolol was associated with an increased risk of hospitalisation for bradycardia. Materials and Methods. A self-controlled case-series study was undertaken in patients who were hospitalised for bradycardia and were exposed to timolol. Person-time after timolol ...

  14. Association between Ophthalmic Timolol and Hospitalisation for Bradycardia

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    Nicole L. Pratt


    Full Text Available Introduction. Ophthalmic timolol, a topical nonselective beta-blocker, has the potential to be absorbed systemically which may cause adverse cardiovascular effects. This study was conducted to determine whether initiation of ophthalmic timolol was associated with an increased risk of hospitalisation for bradycardia. Materials and Methods. A self-controlled case-series study was undertaken in patients who were hospitalised for bradycardia and were exposed to timolol. Person-time after timolol initiation was partitioned into risk periods: 1–30 days, 31–180 days, and >180 days. A 30-day risk period prior to initiating timolol was also included. All remaining time was considered unexposed. Results. There were 6,373 patients with at least one hospitalisation for bradycardia during the study period; 267 were exposed to timolol. Risk of bradycardia was significantly increased in the 31–180 days after timolol initiation (incidence rate ratio (IRR = 1.93; 95% confidence interval (CI 1.00–1.87. No increased risk was observed in the first 30 days or beyond 180 days of continuous exposure (IRR = 1.40; 95% CI 0.87–2.26 and IRR = 1.21; 95% CI 0.64–2.31, resp.. Conclusion. Bradycardia is a potential adverse event following timolol initiation. Practitioners should consider patient history before choosing a glaucoma regime and closely monitor patients after treatment initiation with topical nonselective beta-blocker eye drops.

  15. Toxic Bradycardias in the Critically Ill Poisoned Patient

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    Melissa L. Givens


    Full Text Available Cardiovascular drugs are a common cause of poisoning, and toxic bradycardias can be refractory to standard ACLS protocols. It is important to consider appropriate antidotes and adjunctive therapies in the care of the poisoned patient in order to maximize outcomes. While rigorous studies are lacking in regards to treatment of toxic bradycardias, there are small studies and case reports to help guide clinicians’ choices in caring for the poisoned patient. Antidotes, pressor support, and extracorporeal therapy are some of the treatment options for the care of these patients. It is important to make informed therapeutic decisions with an understanding of the available evidence, and consultation with a toxicologist and/or regional Poison Control Center should be considered early in the course of treatment.

  16. Heart rate regulation and extreme bradycardia in diving emperor penguins. (United States)

    Meir, Jessica U; Stockard, Torre K; Williams, Cassondra L; Ponganis, Katherine V; Ponganis, Paul J


    To investigate the diving heart rate (f(H)) response of the emperor penguin (Aptenodytes forsteri), the consummate avian diver, birds diving at an isolated dive hole in McMurdo Sound, Antarctica were outfitted with digital electrocardiogram recorders, two-axis accelerometers and time depth recorders (TDRs). In contrast to any other freely diving bird, a true bradycardia (f(H) significantly emperor penguins. Maximum instantaneous surface interval f(H) in this study is the highest ever recorded for emperor penguins (256 beats min(-1)), equivalent to f(H) at V(O(2)) max., presumably facilitating oxygen loading and post-dive metabolism. The classic Scholander-Irving dive response in these emperor penguins contrasts with the absence of true bradycardia in diving ducks, cormorants, and other penguin species.

  17. Prolonged bradycardia, asystole and outcome of high spinal cord injury patients: Risk factors and management (United States)

    Shaikh, Nissar; Rhaman, M. A.; Raza, Ali; Shabana, Adel; Malstrom, Mahommad Faisal; Al-Sulaiti, Ghanem


    Background: High spinal cord injury (HSCI) is one of the devastating traumatic injuries. 80% of these patients are young male, and 93% will have major neurological disabilities. There is a paucity of literature about prolonged bradycardia in HSCI patients. The aim of this study was to know the prevalence, risk factors, precipitating factors for prolonged bradycardia in the HSCI patients. Materials and Methods: All patients who were admitted to the Intensive Care Unit (ICU) of a tertiary hospital, with spinal cord injury above level of dorsal (D4) were enrolled in this study prospectively. Patient's demographic data, mechanism, level and type of spinal injury, associated injuries, injury severity score (ISS), spinal shock, vasopressors used, time of occurrence of bradycardia, treatment for bradycardia, precipitating as well as risk factors and outcome were recorded. Results: During the study period, a total of 138 patients were admitted to the ICU with HSCI. Majority of patients were male. The most frequently associated injury in these patients was skeletal fractures (38.4%). Most common complication was pneumonia 56 (41%). Forty-five (33%) of the total patients had prolonged bradycardia; 87% of these patients had pneumonia when bradycardia occurred. 53.4% had cardiac asystole. 29 (21%) patients had bradycardia at the time of endotracheal suctioning, whereas 27 (20%) patients developed bradycardia at the time of positioning. Majority of the patients were managed conservatively. Those HSCI patients who developed prolonged bradycardia, their ISS score was statistically higher, ICU and hospital stay was significantly higher compared with those HSCI patient who did not have prolonged bradycardia. Multivariate analysis revealed that hypotension on admission; pneumonia, and tracheostomy were risk factors for the development of prolonged bradycardia in HSCI patients. Conclusion: Prolonged bradycardia was associated with significantly higher incidence of asystole

  18. Risk factors of bradycardia in 50 cases of gastric surgery under general anesthesia

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    Reza Shariat Moharari


    Conclusion: The history of gastric cancer and previous chemotherapy might be the only common factors that cause to bradycardia and irresponsible asystole during gastric surgery in these patients. It seems that only close monitoring and vigilant anesthesiologist require for treatment and prevention from adverse effect of such a sever bradycardia event.

  19. Severe symptomatic bradycardia after a dinner of spicy oleander soup

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    Andrea Tampieri


    Full Text Available Cardiac glycosides similar to digoxin are produced by different plants in nature. Nerium oleander, commonly grown as an ornamental shrub, can be found worldwide in temperate countries. Intentional or accidental ingestion of any part of the plant can lead to clinically relevant intoxication. A 63-year-old woman came to the emergency department with acute dyspeptic symptoms after eating vegetable soup flavored with unfamiliar flowers she have collected herself. However, the electrocardiography (ECG showed abnormalities that raised suspicions for an overdose of digoxin-like cardiac glycosides. The patient was not on treatment with digoxin and a careful anamnesis revealed that she had eaten oleander leaves. Digoxin specific Fab antibody fragments were administered for marked bradycardia that was not responding to atropine administration, after counseling with the reference toxicology center. The patient was also treated with activated charcoal and magnesium sulphate, intravenous fluids and pantoprazole. Four days later she was discharged as asymptomatic, with normal sinus rhythm. Emergency physicians should be aware of this type of poisoning, especially in cases with typical ECG alterations in patients not treated with digoxin and medical history of plants ingestion. Cardio-active glycosides are present in different plants, often used inappropriately, with potential toxic effects and harmful drug interactions.

  20. Dexmedetomidine Related Bradycardia Leading to Cardiac Arrest in a Dog

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    C. Y. Chen2, K-S. Chen1,2, K. M. Chang2, W. M. Lee1,2, S. C. Chang1,2 and H. C. Wang1,2


    Full Text Available A 2-year-old, mixed breed female dog (16 kg underwent an exploratory laparotomy following ultrasonographic diagnosis of foreign body and a segment of small intestine intussusceptions. The patient was classified as an ASA II. Ketamine (1mg/kg, IV, and dexmedetomidine (2.5 µg/kg, IV, and morphine (0.6 mg/kg, SC were given as anesthetic premedication. Propofol (0.1 mg/kg, IV titrated to a total amount of 4 ml (2.5 mg/ kg was given for intubation. Asystole was occurred. Cardiac resuscitation was then conducted immediately. Atipamezole (0.1 ml was injected, but showed no response on ECG. Atropine (0.02 mg/kg was then injected, and a second dosage was given. Two-three mins later, the heart rate at 84 beats/min. The NIBP showed 203/132 with MAP 153 mmHg, and the SpO2 showed 95% after the cardiac function was regained. Dexmedetomidine related bradycardia leading to cardiac arrest has been suggested in this case.

  1. Rare Case of Rapidly Worsening REM Sleep Induced Bradycardia

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    Ayyappa S. Duba


    Full Text Available Sinoatrial arrest also known as sinus pause occurs when sinoatrial node of the heart transiently ceases to generate the electrical impulse necessary for the myocardium to contract. It may last from 2.0 seconds to several minutes. Etiologies of sinoatrial arrest can be complex and heterogeneous. During rapid eye movement (REM sleep, sinus arrests unrelated to apnea or hypopnea are very rare and only a few cases have been reported. Here we report a case of 36-year-old male with no significant past medical history who presented to our hospital after a syncopal episode at night. Physical examination showed no cardiac or neurological abnormalities and initial EKG and neuroimaging were normal. Overnight telemonitor recorded several episodes of bradyarrhythmia with sinus arrest that progressively lengthened over time. Sleep study was done which confirmed that sinus arrests occurred more during REM sleep and are unrelated to apnea or hypopnea. Electrophysiology studies showed sinus nodal dysfunction with no junctional escape, subsequently a dual chamber pacemaker placed for rapidly worsening case of REM sleep induced bradycardia.

  2. Prolonged bradycardia, asystole and outcome of high spinal cord injury patients: Risk factors and management



    Background: High spinal cord injury (HSCI) is one of the devastating traumatic injuries. 80% of these patients are young male, and 93% will have major neurological disabilities. There is a paucity of literature about prolonged bradycardia in HSCI patients. The aim of this study was to know the prevalence, risk factors, precipitating factors for prolonged bradycardia in the HSCI patients. Materials and Methods: All patients who were admitted to the Intensive Care Unit (ICU) of a tertiary hospi...

  3. Ballooning-induced bradycardia during carotid stenting in primary stenosis and restenosis

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    Nano, Giovanni; Dalainas, Ilias; Bianchi, Paolo; Stegher, Silvia; Malacrida, Giovanni; Tealdi, Domenico G. [University of Milan, Istituto Policlinico San Donato, Milan (Italy); Bet, Luciano [University of Milan, Neurology Department, Istituto Policlinico San Donato, Milan (Italy)


    We compared the incidence of intraprocedural bradycardia and hypotension during carotid artery stenting in patients with primary carotid artery stenosis and those with prior ipsilateral carotid endarterectomy. A total of 213 carotid stenting procedures were performed in our institution in a 4-year period. The mean degree of stenosis was 78% (range 60-99%). Of these 213 procedures, 43 were performed for carotid restenosis, 9 after stenting and 34 after endarterectomy, and 170 for primary stenosis. Atropine was selectively administrated if patients suffered bradycardia (a decrease in heart rate to <50% or an absolute heart rate of <40 bpm) or hypotension (systolic blood pressure <90 mmHg). We compared the group of patients with primary stenosis (n=170) and the group of patients with restenosis after carotid endarterectomy (n=34) in relation to intraprocedural hypotension or bradycardia/need for atropine administration. Hypotension occurred in 49 patients with primary stenosis and 2 patients with restenosis. The difference was statistically significant. Atropine was administered for bradycardia to 58 patients with primary stenosis and 3 patients with restenosis. The difference was statistically significant. Intraprocedural bradycardia and hypotension occur more frequently in patients with primary carotid artery stenosis. (orig.)

  4. Enhanced bradycardia induced by beta-adrenoceptor antagonists in rats pretreated with isoniazid. (United States)

    Vidrio, H; Sánchez-Salvatori, M A; Medina, M


    High doses of isoniazid increase hypotension induced by vasodilators and change the accompanying reflex tachycardia to bradycardia, an interaction attributed to decreased synthesis of brain gamma-aminobutyric acid (GABA). In the present study, the possible enhancement by isoniazid of bradycardia induced by beta-adrenoceptor antagonists was determined in rats anaesthetised with chloralose-urethane. Isoniazid significantly increased bradycardia after propranolol, pindolol, labetalol and atenolol, as well as after clonidine, but not after hexamethonium or carbachol. Enhancement was not observed in rats pretreated with methylatropine or previously vagotomised. These results are compatible with interference by isoniazid with GABAergic inhibition of cardiac parasympathetic tone. Such interference could be exerted centrally, possibly at the nucleus ambiguus, or peripherally at the sinus node.

  5. [Electrocardiographic study of sinus bradycardia associated with enterohemorrhagic Escherichia coli O157: H7 infection]. (United States)

    Sanada, M; Okano, H; Yokota, S; Kanikawa, T; Itou, T; Oh-ishi, T; Ogawa, K


    A severe outbreak of hemorrhagic colitis occurred at a kindergarten in Saitama, Japan in October, 1990. Children who were affected by enterohemorrhagic E. coli O157: H7 infection showed apparent bradycardia as well as severe bloody diarrhea, generalized convulsion, or hemolytic uremic syndrome. Cardiac involvement such as bradycardia observed in the patients of this outbreak has not been described in previous reports about EHEC infection, while bradycardia has been well known in typhoid fever due to salmonella typhosa infection. Electrocardiographic examination was performed to evaluate bardicardia, utilizing electrocardiography at rest and Holter's twenty-four hour electrocardiography. In the report, we demonstrate that the bradicardia was due to reduced frequency of sinus node. Both average heart rate and average minimum heart rate of the patients at night (74.0 +/- 5.6 BPM and 57.0 +/- 5.1 BPM, respectively) decreased significantly, as compared with controls (84.6 +/- 9.3 BPM and 66.3 +/- 8.0 BPM respectively) (p < 0.01). CVRR of the patients (0.120 +/- 0.019, respectively) increased significantly as compared with controls (0.090 +/- 0.010, respectively). These results indicate that an activated parasympathetic nervous system, that is, activation of the vagal nerve, might have induced the sinus bradycardia observed in the patients with EHEC infection.

  6. Cardiac responses of vagus nerve stimulation: Intraoperative bradycardia and subsequent chronic stimulation

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    Ardesch, J.J.; Buschman, H.P.J.; Burgh, van der P.H.; Wagener-Schimmel, L.J.; Aa, van der H.E.; Hageman, G.


    OBJECTIVES: Few adverse events on heart rate have been reported with vagus nerve stimulation (VNS) for refractory epilepsy. We describe three cases with intraoperative bradycardia during device testing. PATIENTS AND METHODS: At our hospital 111 patients have received a VNS system. Intraoperative dev

  7. [Bradycardia and asystolia secondary to epileptic crisis. Report of a case]. (United States)

    Moreno, R; Bueno, H; Pérez de Prado, A; Barriga, F; Díaz, F; Soriano, J; Fernández de Bodadilla, J; Pérez-Villacastín, J; Arenal, A; Almendral, J; Delcán, J L


    We report the case of a 21 year old man with bradycardia and asystolia after a seizure. No cardiac disease could be demonstrated, but electroencephalography after sleep deprivation showed the presence of a temporal irritative focus. The importance of differential diagnosis between cardiogenic syncope and loss of consciousness due to epilepsy is discussed.

  8. Sinus bradycardia as a predictor of right coronary artery occlusion in patients with inferior myocardial infarction. (United States)

    Serrano, C V; Bortolotto, L A; César, L A; Solimene, M C; Mansur, A P; Nicolau, J C; Ramires, J A


    Differentiation of right coronary artery (RCA) from left circumflex artery (LCxA) occlusion may be difficult since both can present an electrocardiographic pattern of inferior myocardial infarction (IMI). We studied 133 patients with IMI, 92 patients with RCA occlusion and 41 patients with LCxA occlusion. Risk factors such as previous MI, arterial hypertension, diabetes, smoking, and dislipemia, were similar for RCA and LCxA occlusions. Patients with RCA occlusion had a higher incidence of isolated IMI than patients with LCxA occlusion, 50% vs. 17%, respectively (P<0.001). Arterial hypotension was more prevalent (P<0.05) among patients with RCA (18%) rather than those with LCxA occlusion (2%). RCA occlusion presented an association with sinus bradycardia, an association not observed with LCxA occlusion (15% vs. 0%, respectively; P<0.01). Total atrioventricular block was only present among patients with RCA (18%). Proximal occlusions of the RCA presented lower heart rates (sinus bradycardia) than medial and distal occlusions (13% vs. 1% and 1%, respectively; P<0.0001 and P<0.001). Therefore, regarding patients with IMI: (1) sinus bradycardia is more frequent when the infarct-related artery is the RCA; (2) proximal occlusions of the right coronary predispose low heart rates; and (3) occlusion of the LCxA rarely induces sinus bradycardia.

  9. Reflex bradycardia induced by hydralazine in sino-aortic deafferented conscious rats. (United States)

    Sánchez-Salvatori, M A; Vidrio, H


    1. It is generally recognized that the vasodilator hydralazine produces hypotension accompanied by baroreflex-mediated tachycardia. In some experimental conditions, however, the accompanying heart rate change is bradycardia, a paradoxical response which has not been satisfactorily explained. The present study examined the possibility of hydralazine-induced bradycardia being mediated by vagal or sympathetic afferents activated by changes in left ventricular pressure. 2. Systolic blood pressure and heart rate responses to hydralazine were recorded in conscious normotensive intact rats by a tail cuff method and compared with responses in animals subjected to previous sino-aortic deafferentation (SAD) to remove the influence of the arterial baroreflex. Responses were also obtained after blockade of myocardial afferent vagal C-fibres with urethane, of efferent vagal impulses to the heart with methylatropine, of positive inotropic effects of hydralazine with atenolol, and of prostanoid sensitization of myocardial nerve fibres with indomethacin. 3. Hydralazine produced hypotension and tachycardia in intact rats, and hypotension and bradycardia in SAD animals. In intact rats, this pattern was not affected by any of the pretreatments, while in SAD rats, all pretreatments reversed the bradycardia to hydralazine. 4. The present results indicate that suppression of the arterial baroreflex by SAD propitiates the appearance of a bradycardiac response to hydralazine. This reaction probably results from activation of a vagal cardiodepressant reflex originating in the heart, as suggested by its blockade by drugs acting at various sites along the reflex arch.

  10. Normal Sinus Rhythm-Sinus Bradycardia is Common in Young Children Post-extracardiac Fontan. (United States)

    Evans, William N; Acherman, Ruben J; Restrepo, Humberto


    We hypothesized that normal sinus rhythm-sinus bradycardia is common in young children following extracardiac Fontan. After excluding patients with sinus pauses, junctional rhythm, tachy-brady syndrome, frequent ectopics, or ectopic atrial rhythm, we found an ambulatory 24-h Holter monitor average heart rate of 78 ± 12 beats per minute (bpm) in 33 post-extracardiac Fontan children with a median age of 6 years (5-10). A 24-h average heart rate of 78 ± 12 bpm is statistically significantly lower than a 24-h average heart rate value of 90 ± 10 bpm derived from a similarly aged control population (p < 0.01). We conclude that after excluding those with significant arrhythmias, normal sinus rhythm-sinus bradycardia is common in children post-extracardiac Fontan.

  11. Noncardiogenic Pulmonary Edema after Amlodipine Overdose without Refractory Hypotension and Bradycardia



    Amlodipine overdose can be life-threatening when manifesting as noncardiogenic pulmonary edema. Treatment remains challenging. We describe a case of noncardiogenic pulmonary edema without refractory hypotension and bradycardia after ingestion of 500 milligram amlodipine with suicidal intent. Mechanical ventilation, dexamethasone, atrovent HFA (ipratropium), pulmicort inhalation, and antibiotic therapy were used for the management. Length of hospital stay was 11 days. The patient was discharge...

  12. Noncardiogenic Pulmonary Edema after Amlodipine Overdose without Refractory Hypotension and Bradycardia

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    M. Hedaiaty


    Full Text Available Amlodipine overdose can be life-threatening when manifesting as noncardiogenic pulmonary edema. Treatment remains challenging. We describe a case of noncardiogenic pulmonary edema without refractory hypotension and bradycardia after ingestion of 500 milligram amlodipine with suicidal intent. Mechanical ventilation, dexamethasone, atrovent HFA (ipratropium, pulmicort inhalation, and antibiotic therapy were used for the management. Length of hospital stay was 11 days. The patient was discharged with full recovery.

  13. Noncardiogenic Pulmonary Edema after Amlodipine Overdose without Refractory Hypotension and Bradycardia (United States)

    Hedaiaty, M.; Eizadi-Mood, N.; Sabzghabaee, A. M.


    Amlodipine overdose can be life-threatening when manifesting as noncardiogenic pulmonary edema. Treatment remains challenging. We describe a case of noncardiogenic pulmonary edema without refractory hypotension and bradycardia after ingestion of 500 milligram amlodipine with suicidal intent. Mechanical ventilation, dexamethasone, atrovent HFA (ipratropium), pulmicort inhalation, and antibiotic therapy were used for the management. Length of hospital stay was 11 days. The patient was discharged with full recovery. PMID:26075111

  14. Therapeutic class-specific signal detection of bradycardia associated with propranolol hydrochloride

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    Gavali Dhaval


    Full Text Available Background: Propranolol hydrochloride, one of the most widely used β-blocker in the treatment of hypertension since 1960s, shows a number of serious and non-serious adverse events. Objective: Major objectives of this study were to extract the Canadian Adverse Drug Reaction Monitoring Program (CADRMP database for possible toxic signal detection (SD of propranolol hydrochloride, evaluate the frequency of the bradycardia associated with it in different stratified groups for a putative signal, and generate awareness in healthcare professionals regarding usefulness of SD. Materials and Methods: Appropriate statistical methods were used for adverse drug reaction (ADR signal detection such as, proportional reporting ratio (PRR; reporting odds ratio (ROR; the Chi-square (λ2 statistic method; the 95% confidence interval (CI; the observed to expected ratio (O/E; and Du Mouchel method were used to calculate the possible signals. Significance of λ2 and other calculated statistics, e.g., PRR and ROR, was based on a composite criterion of regulatory guidelines and not on any particular statistical level of significance. Results: Calculated statistics by different methods were compared with the regulatory criteria of a statistic value ≥4.0 for λ2 , and ≥3.0 for the rest for SD to be declared significant. The PRR statistic was found to be 2.5054; by the ROR method it was 2.5820; the λ2 statistic was 3.2598, whereas the lower and upper limits of 95% CI of PRR were found to be 0.0778 and 1.9104, respectively, by the O/E ratio was found to be 2.3978, and PRR with the help of Du Mouchel was found to be 2.3979. Thus, the bradycardia-propranolol signals calculated in this study were not significant. Conclusions: The therapeutic class specific signal of bradycardia associated with propranolol hydrochloride was not found potent enough to cause bradycardia. However, since the calculated statistics were very high albeit not significant, the possibility of

  15. Profound bradycardia with lidocaine during anesthesia induction in a silent sick sinus syndrome patient. (United States)

    Kim, Kyoung Ok; Chung, Seunghyun; Lee, Kyoungjin; Cho, Hun


    Sick sinus syndrome is caused by sinus node dysfunction that renders it unable to function as a pacemaker. Patients with sick sinus syndrome are often asymptomatic or have symptoms that are mild and nonspecific. Lidocaine (0.5 mg/kg) injection is used for reduction of pain associated with intravenous injection of propofol. Episodes of marked bradycardia with sinus arrest after prophylactic lidocaine injection are reported in a 69-y-old man with no apparent preoperative cardiac disease or electrocardiographic abnormality. Surgery was postponed, and he was later diagnosed with sick sinus syndrome.

  16. Bradycardia without hypertension and bradypnea in acute traumatic subdural hematoma is a sensitive predictor of the Cushing triad: 3 case reports



    Acute traumatic subdural hematomas (SDHs) are very common. These hematomas are usually neurosurgical emergencies, although conservative therapy is indicated in certain cases. SDH can increase intracranial pressure (ICP) and compress or stretch the brainstem. Lately, it has been recognized that increased ICP can lead to hemodynamic instability and bradycardia. Bradycardia can be an early warning sign in many neurosurgical conditions. We observed bradycardia in serial cases of the patient witho...

  17. Uterine hypertonia and nuchal cord causing severe fetal bradycardia in a parturient receiving combined spinal-epidural analgesia during labor: Case report and review of literature

    Directory of Open Access Journals (Sweden)

    Uma Srivastava


    Full Text Available Fetal bradycardia is common following spinal opioids administered for pain relief during labor. This slowing is usually benign and short lived. Although it leads to some anxiety among obstetricians and anesthesiologists, it rarely results in urgent operative delivery. Here, we are reporting a case where urgent caesarean delivery was needed due to severe and persistent fetal bradycardia following low-dose intrathecal fentanyl. Fetal bradycardia possibly was due to hypertonic uterine contractions complicated by tightly wrapped cord round the neck.

  18. Ictal central apnea and bradycardia in temporal lobe epilepsy complicated by obstructive sleep apnea syndrome

    Directory of Open Access Journals (Sweden)

    Yoko Nishimura


    Full Text Available We describe the case of a 12-year-old boy who developed temporal lobe epilepsy (TLE with daily complex partial seizures (CPS and monthly generalized seizures. Moreover, he frequently snored while asleep since early childhood. Polysomnography (PSG revealed severe obstructive sleep apnea with apnea–hypopnea index (AHI of 37.8/h. Video-PSG with simultaneous electroencephalography (EEG recording captured two ictal apneic episodes during sleep, without any motor manifestations. The onset of rhythmic theta activity in the midtemporal area on EEG was preceded by the onset of apnea by several seconds and disappeared soon after cessation of central apnea. One episode was accompanied by ictal bradycardia of <48 beats/min which persisted for 50 s beyond the end of epileptic activity. After treatment with carbamazepine and tonsillectomy/adenoidectomy, the seizures were well controlled and AHI decreased to 2.5/h. Paroxysmal discharges also disappeared during this time. Uncontrolled TLE complicated by sleep apnea should be evaluated for the presence of ictal central apnea/bradycardia.

  19. The Effect of Atropine on Post-ECT Bradycardia in Patients with Major Depressive Disorder

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    Hassan Farashbandi


    Full Text Available Background: Electroconvulsive therapy (ECT is utilized for treatment of a range of psychiatric disorders including major depressive disorder (MDD. One of the major complications in using ECT is cardiovascular problems i.e., bradycardia. The present study was designed to investigate the effect of atropine on the pulse rate (PR of the patients under treatment with ECT. Materials and Methods: In this randomized clinical trial, 30 patients with diagnosis of MDD who received atropine before ECT treatment (control group were compared with 30 patients with the same diagnosis without receiving atropine (experimental group under ECT treatment. Both groups received ECT under the same term and condition. The PR of the patients were recorded 7 times (twice before anesthesia and ECT and 5 fixed one min intervals immediately after receiving ECT; for 10 sessions of treatment with ECT (3 times a week. The results were analyzed using repeated measure analysis of variance. The PR under 50 was the cut off point for differentiating the patients suffering from bradycardia and those without it. Results: Slight increment in PRs for experimental group (patient who did not receive atropine in contrast to control group were observed, but it did not reach a statistically significant level. The gender (male/female did not have different PR. The age of the patients and initial PR (regarded as co-variances did not show significant effect on PR for total sample. Conclusion: There seems to be not necessary to use atropine treatment for depressed patients receiving ECT.

  20. Hyperpotassemia and bradycardia in a bedridden elderly woman with selective hypoaldosteronism associated with low renin activity. (United States)

    Inada, Mitsuo; Iwasaki, Keiko; Imai, Chihiro; Hashimoto, Satoshi


    A bedridden 85-year-old woman had hyperpotassemia (7.7 mEq/L) and bradycardia (30/min). Endocrinologic findings revealed a decrease in the renin-aldosterone system and normal adrenoglucocorticoid function. The results were consistent with the abnormalities seen in selective hypoaldosteronism with low renin activity. In addition, 9 of 11 patients, selected randomly from 72 bedridden elderly patients with normal serum sodium and potassium levels in our hospital, had diminished plasma renin activity (PRA) and plasma aldosterone concentration (PAC). The present patient was prescribed nonsteroidal anti-inflammatory drug (NSAID). NSAID reduces renal potassium excretion through the inhibition of renal prostaglandin synthesis. Therefore, the use of NSAID in bedridden elderly patients might intensify the underlying asymptomatic hypoaldosteronism and cause life-threatening hyperpotassemia.

  1. Deep-diving sea lions exhibit extreme bradycardia in long-duration dives. (United States)

    McDonald, Birgitte I; Ponganis, Paul J


    Heart rate and peripheral blood flow distribution are the primary determinants of the rate and pattern of oxygen store utilisation and ultimately breath-hold duration in marine endotherms. Despite this, little is known about how otariids (sea lions and fur seals) regulate heart rate (fH) while diving. We investigated dive fH in five adult female California sea lions (Zalophus californianus) during foraging trips by instrumenting them with digital electrocardiogram (ECG) loggers and time depth recorders. In all dives, dive fH (number of beats/duration; 50±9 beats min(-1)) decreased compared with surface rates (113±5 beats min(-1)), with all dives exhibiting an instantaneous fH below resting (100 m) consisted of: (1) an initial rapid decline in fH resulting in the lowest instantaneous fH of the dive at the end of descent, often below 10 beats min(-1) in dives longer than 6 min in duration; (2) a slight increase in fH to ~10-40 beats min(-1) during the bottom portion of the dive; and (3) a gradual increase in fH during ascent with a rapid increase prior to surfacing. Thus, fH regulation in deep-diving sea lions is not simply a progressive bradycardia. Extreme bradycardia and the presumed associated reductions in pulmonary and peripheral blood flow during late descent of deep dives should (a) contribute to preservation of the lung oxygen store, (b) increase dependence of muscle on the myoglobin-bound oxygen store, (c) conserve the blood oxygen store and (d) help limit the absorption of nitrogen at depth. This fH profile during deep dives of sea lions may be characteristic of deep-diving marine endotherms that dive on inspiration as similar fH profiles have been recently documented in the emperor penguin, another deep diver that dives on inspiration.

  2. Disruption of bradycardia associated with discriminative conditioning in combat veterans with PTSD

    Directory of Open Access Journals (Sweden)

    Jay P Ginsberg


    Full Text Available Jay P Ginsberg1,2, Edwin Ayers3, Louisa Burriss1, Donald A Powell1,41Shirley L. Buchanan Neuroscience Laboratory, Dorn VA Medical Center, Columbia, SC, USA; 2Department of Pharmacology, Physiology, and Neuroscience, School of Medicine, 4Department of Psychology, University of South Carolina, Columbia, SC, USA; 3Department of Psychology, South Carolina State University, Orangeburg, SC, USAAbstract: The effects of combat-related posttraumatic stress disorder (PTSD on heart rate (HR responding associated with a discriminative delay eyeblink (EB conditioning paradigm are reported. Combat PTSD+, Combat PTSD−, and Noncombat PTSD− veterans were assessed with psychometric self-report measures, and baseline heart rate variability (HRV was measured before receiving a 72-trial session of discriminative EB classical conditioning. Two types (red or green light of conditioned stimuli (CS were used: one (CS+ predicted a tone, followed immediately by an aversive stimulus (corneal airpuff; the other (CS− predicted a tone alone, not followed by the airpuff. The light signal was presented for 5 seconds, during which HR was measured. On all psychometric measures, the PTSD+ subgroup was significantly different from the PTSD− subgroups (Combat + Noncombat, and the PTSD− subgroups did not significantly differ from each other. A linear deceleration in HR to CS+ and CS− signals was found in the combined PTSD− subgroup and on CS− trials in the PTSD+ subgroup, but was not present on CS+ trials in the PTSD+ subgroup. Results are interpreted with respect to a behavioral stages model of conditioned bradycardia and in terms of neural substrates which are both critical to HR conditioning and known to be abnormal in PTSD.Keywords: bradycardia, PTSD, combat veterans, classical conditioning

  3. The Calcium/Calmodulin/Kinase System and Arrhythmogenic Afterdepolarizations in Bradycardia-Related Acquired Long-QT Syndrome

    NARCIS (Netherlands)

    Qi, XiaoYan; Yeh, Yung-Hsin; Chartier, Denis; Xiao, Ling; Tsuji, Yukiomi; Brundel, Bianca J. J. M.; Kodama, Itsuo; Nattel, Stanley


    Background-Sustained bradycardia is associated with long-QT syndrome in human beings and causes spontaneous torsades de pointes in rabbits with chronic atrioventricular block (CAVB), at least partly by downregulating delayed-rectifier K(+)-current to cause action potential (AP) prolongation. We addr

  4. Intractable episodic bradycardia resulting from progressive lead traction in an epileptic child with a vagus nerve stimulator: a delayed complication. (United States)

    Clark, Aaron J; Kuperman, Rachel A; Auguste, Kurtis I; Sun, Peter P


    Vagus nerve stimulation (VNS) is used as palliation for adult and pediatric patients with intractable epilepsy who are not candidates for curative resection. Although the treatment is generally safe, complications can occur intraoperatively, perioperatively, and in a delayed time frame. In the literature, there are 2 reports of pediatric patients with implanted VNS units who had refractory bradycardia that resolved after the stimulation was turned off. The authors report the case of a 13-year-old boy with a history of vagus nerve stimulator placement at 2 years of age, who developed intractable episodic bradycardia that persisted despite the cessation of VNS and whose imaging results suggested vagus nerve tethering by the leads. He was subsequently taken to the operating room for exploration, where it was confirmed that the stimulator lead was exerting traction on the vagus nerve, which was displaced from the carotid sheath. After the vagus nerve was untethered and the leads were replaced, the bradycardia eventually resolved with continual effective VNS therapy. When placing a VNS unit in a very young child, accommodations must be made for years of expected growth. Delayed intractable bradycardia can result from a vagus nerve under traction by tethered stimulator leads.


    NARCIS (Netherlands)



    The purpose of this study was to determine the incidence of late potentials and their relation to QT prolongation in a family with a high incidence of sudden death during sleep at a young age and bradycardia-dependent QT prolongation (n = 9) and to compare the findings with those in consanguineous f

  6. Switching Kalman filter based methods for apnea bradycardia detection from ECG signals. (United States)

    Montazeri Ghahjaverestan, Nasim; Shamsollahi, Mohammad B; Ge, Di; Hernández, Alfredo I


    Apnea bradycardia (AB) is an outcome of apnea occurrence in preterm infants and is an observable phenomenon in cardiovascular signals. Early detection of apnea in infants under monitoring is a critical challenge for the early intervention of nurses. In this paper, we introduce two switching Kalman filter (SKF) based methods for AB detection using electrocardiogram (ECG) signal.The first SKF model uses McSharry's ECG dynamical model integrated in two Kalman filter (KF) models trained for normal and AB intervals. Whereas the second SKF model is established by using only the RR sequence extracted from ECG and two AR models to be fitted in normal and AB intervals. In both SKF approaches, a discrete state variable called a switch is considered that chooses one of the models (corresponding to normal and AB) during the inference phase. According to the probability of each model indicated by this switch, the model with larger probability determines the observation label at each time instant.It is shown that the method based on ECG dynamical model can be effectively used for AB detection. The detection performance is evaluated by comparing statistical metrics and the amount of time taken to detect AB compared with the annotated onset. The results demonstrate the superiority of this method, with sensitivity and specificity 94.74[Formula: see text] and 94.17[Formula: see text], respectively. The presented approaches may therefore serve as an effective algorithm for monitoring neonates suffering from AB.

  7. Arterial baroreceptors and brain histamine contribute to bradycardia to peripheral hyperosmolality. (United States)

    Kenney, M J; Bealer, S L


    The purpose of this study was to determine whether the bradycardic response to peripheral hyperosmolality in conscious rats is dependent on afferent baroreceptor mechanisms and whether central histamine H2 receptors play a role in baroreflex-mediated changes in heart rate (HR). Mean arterial pressure (MAP) and HR were recorded continuously during a 30-min infusion of 2.5 M NaCl (10 microliters.100 g-1.min-1) hypertonic saline (HTS). HTS infusion significantly increased MAP (21 +/- 4 mmHg) and reduced HR (-62 +/- 10 beats/min) in rats with intact arterial baroreceptors. In sinoaortic-denervated rats, HR remained unchanged from control despite a significant increase in MAP. After intracerebroventricular (lateral ventricle) administration of cimetidine or ranitidine (H2-receptor antagonists) in intact rats, HTS infusion significantly increased MAP (19 +/- 2 and 17 +/- 2 mmHg, respectively) but the bradycardia was abolished (-12 +/- 10 and -10 +/- 10 beats/min, respectively). In contrast, central H2-receptor blockade did not alter reflex HR responses to the intravenous administration of phenylephrine and nitroprusside or to the central administration of histamine or angiotensin II. These results indicate that the bradycardic response to HTS infusion is mediated through the arterial baroreceptor reflex and involves in part a selective histaminergic pathway.

  8. The anatomical basis of bradycardia-tachycardia syndrome in elderly dogs with chronic degenerative valvular disease. (United States)

    Nakao, S; Hirakawa, A; Fukushima, R; Kobayashi, M; Machida, N


    The hearts of seven elderly dogs in which bradycardia-tachycardia syndrome (BTS) had been diagnosed electrocardiographically were examined post mortem. The clinical basis of the underlying heart disease was invariably mitral or mitral and tricuspid regurgitation. Microscopical examination of the sinoatrial (SA) node and the SA junctional region consistently revealed depletion of SA nodal cells, with a corresponding increase in fibrous or fibro-fatty tissue that interrupted contiguity between the SA node and the surrounding atrial myocardium. The left and right atrial walls showed an increased amount of fibrous tissue in the myocardium and disruption of the muscle bundle architecture (interstitial myocardial fibrosis) to varying degrees. Qualitatively, these changes in the SA node and the SA node region resembled those associated with ageing in elderly people with or without BTS. Thus, it is possible that the pathological process affecting the SA node in these dogs was fundamentally related to ageing and may have caused BTS, in combination with atrial myocardial lesions caused by mitral and tricuspid regurgitation.

  9. Reflex bradycardia does not influence oxygen consumption during hypoxia in the European eel (Anguilla anguilla)

    DEFF Research Database (Denmark)

    Iversen, Nina Kerting; McKenzie, David; Malte, H.


    of the muscarinic antagonist atropine (5 mg kg-1). In the untreated eels, f H fell from 39.0 ± 4.3 min-1 in normoxia to 14.8 ± 5.2 min-1 at the deepest level of hypoxia (2 kPa), and this was associated with a decline in Q, from 7.5 ± 0.8 mL min-1 kg-1 to 3.3 ± 0.7 mL min-1 kg-1 in normoxia versus deepest hypoxia......, respectively. Atropine had no effect on SMR, which was 16.0 ± 1.8 μmol O2 kg-1 min-1 in control versus 16.8 ± 0.8 μmol O2 kg-1 min-1 following treatment with atropine. Atropine also had no significant effect on normoxic f H or Q in the eel, but completely abolished the bradycardia and associated decline in Q...

  10. Diving bradycardia of elderly Korean women divers, haenyeo, in cold seawater: a field report. (United States)

    Lee, Joo-Young; Lee, Hyo-Hyun; Kim, Siyeon; Jang, Young-Joon; Baek, Yoon-Jeong; Kang, Kwon-Yong


    The purpose of the present field study was to explore diving patterns and heart rate of elderly Korean women divers (haenyeo) while breath-hold diving in cold seawater. We hypothesized that the decreasing rate in heart rate of elderly haenyeos during breath-hold diving was greater and total diving time was shorter than those of young haenyeos from previous studies. Nine haenyeos participated in a field study [68 ± 10 yr in age, ranged from 56 to 83 yr] at a seawater temperature of 10 to 13 °C. Average total diving time including surface swimming time between dives was 253 ± 73 min (155-341 min). Total frequency of dives was 97 ± 28 times and they dived 23 ± 8 times per hour. All haenyeos showed diving bradycardia with a decreased rate of 20 ± 8% at the bottom time (101 ± 20 bpm) when compared to surface swimming time (125 ± 16 bpm) in the sea. Older haenyeos among the nine elderly haenyeos had shorter diving time, less diving frequencies, and lower heart rate at work (p<0.05). These reductions imply that haenyeos voluntarily adjust their workload along with advancing age and diminished cardiovascular functions.

  11. Exercise at depth alters bradycardia and incidence of cardiac anomalies in deep-diving marine mammals. (United States)

    Williams, Terrie M; Fuiman, Lee A; Kendall, Traci; Berry, Patrick; Richter, Beau; Noren, Shawn R; Thometz, Nicole; Shattock, Michael J; Farrell, Edward; Stamper, Andy M; Davis, Randall W


    Unlike their terrestrial ancestors, marine mammals routinely confront extreme physiological and physical challenges while breath-holding and pursuing prey at depth. To determine how cetaceans and pinnipeds accomplish deep-sea chases, we deployed animal-borne instruments that recorded high-resolution electrocardiograms, behaviour and flipper accelerations of bottlenose dolphins (Tursiops truncatus) and Weddell seals (Leptonychotes weddellii) diving from the surface to >200 m. Here we report that both exercise and depth alter the bradycardia associated with the dive response, with the greatest impacts at depths inducing lung collapse. Unexpectedly, cardiac arrhythmias occurred in >73% of deep, aerobic dives, which we attribute to the interplay between sympathetic and parasympathetic drivers for exercise and diving, respectively. Such marked cardiac variability alters the common view of a stereotypic 'dive reflex' in diving mammals. It also suggests the persistence of ancestral terrestrial traits in cardiac function that may help explain the unique sensitivity of some deep-diving marine mammals to anthropogenic disturbances.

  12. Aromatherapy with Rosa Damascenes in Apnea, Bradycardia and Spo2 of Preterm Infants; a Randomized Clinical Trial

    Directory of Open Access Journals (Sweden)

    Saeideh Aghagoli


    Full Text Available Background  Apnea is one of the most common problems in preterm neonates. This study aimed to evaluate the effectiveness of aromatherapy on the reduction of apnea, bradycardia, and Pulse Oximetry (SPO2 in premature infants. Materials and Methods In a clinical trial study, 60 preterm neonates randomly divided in two groups and exposed to aromatherapy with Rosa damascenes distillate or distilled water beside the routine treatment. In experimental group, two drops of 10% Rosa damascenes distillate was dropped on the pad eye in second day of birth at 6 Am. The intervention was repeated in 9 AM, 12 Am, 15 PM and 18 PM hours. A same condition applied for control group and distilled water was dropped on the pad eye. The number of apnea attacks, bradycardia and decrease in SpO2 compared between two groups using chi-square test, independent t-test and repeated measure test. Results The overall apnea attacks, bradycardia, and SPO2 in tree studied days were lower in intervention group than control group (0.47±0.13 vs. 2.6±0.41, 0.47±0.13 vs. 2.56±0.41 and 0.70±0.17 vs. 2.77±0.21, respectively. In addition, the repeated measurement test showed that the mean number of apnea attacks, decrease in heart pulse rate, and decrease in SpO2 was statistically lower in intervention group with aromatherapy than controls in first, second, third and sum of three days (P< 0.05. Conclusion Aromatherapy with Rosa damascenes distillate can reduce more and speedy the occurrence of apnea attacks, bradycardia and SPO2 in premature infants, along with other routine treatment.

  13. Cooling device for bradycardia based on Peltier element for accurate anastomosis of off-pump coronary artery bypass grafting. (United States)

    Kuniyoshi, Yukio; Koja, Kageharu; Miyagi, Kazufumi; Shimoji, Mituyoshi; Uezu, Tooru; Arakaki, Katuya; Yamashiro, Satoshi; Mabuni, Katuhito; Senaha, Shigenobu


    Upon introducing off-pump coronary artery bypass grafting (CABG), the indications for CABG were expanded to include patients who previously had no operative indications. For accurate anastomosis, various devices and methods have been developed. Bradycardia is easily induced by drug administration. However, this method of achieving bradycardia also has adverse effects on cardiac function. We have developed a new device to decrease the heart rate by regional cooling of the sino-atrial node. The new device is incorporated with Peltier's element, which uses an electric charge to create a temperature gradient on both of its surfaces. In terms of the cooling ability of this device, its cooling surface is chilled from 25 degrees C to 0 degrees C within 30 s. During in vivo animal experiments, this device has been shown to decrease the myocardial temperature around the sino-atrial node to 15 degrees C and suppress sino-atrial node activity, resulting in bradycardia to 60 beats/min level. In summary, the simple and easily applicable device for local cooling in combination with the application of diltiazem for effective heart rate reduction may be very helpful for the surgeon and may avoid disadvantages for critically ill patients.

  14. Neuromodulation of Limb Proprioceptive Afferents Decreases Apnea of Prematurity and Accompanying Intermittent Hypoxia and Bradycardia.

    Directory of Open Access Journals (Sweden)

    Kalpashri Kesavan

    Full Text Available Apnea of Prematurity (AOP is common, affecting the majority of infants born at <34 weeks gestational age. Apnea and periodic breathing are accompanied by intermittent hypoxia (IH. Animal and human studies demonstrate that IH exposure contributes to multiple pathologies, including retinopathy of prematurity (ROP, injury to sympathetic ganglia regulating cardiovascular action, impaired pancreatic islet cell and bone development, cerebellar injury, and neurodevelopmental disabilities. Current standard of care for AOP/IH includes prone positioning, positive pressure ventilation, and methylxanthine therapy; these interventions are inadequate, and not optimal for early development.The objective is to support breathing in premature infants by using a simple, non-invasive vibratory device placed over limb proprioceptor fibers, an intervention using the principle that limb movements trigger reflexive facilitation of breathing.Premature infants (23-34 wks gestational age, with clinical evidence of AOP/IH episodes were enrolled 1 week after birth. Caffeine treatment was not a reason for exclusion. Small vibration devices were placed on one hand and one foot and activated in 6 hour ON/OFF sequences for a total of 24 hours. Heart rate, respiratory rate, oxygen saturation (SpO2, and breathing pauses were continuously collected.Fewer respiratory pauses occurred during vibration periods, relative to baseline (p<0.005. Significantly fewer SpO2 declines occurred with vibration (p<0.05, relative to control periods. Significantly fewer bradycardic events occurred during vibration periods, relative to no vibration periods (p<0.05.In premature neonates, limb proprioceptive stimulation, simulating limb movement, reduces breathing pauses and IH episodes, and lowers the number of bradycardic events that accompany aberrant breathing episodes. This low-cost neuromodulatory procedure has the potential to provide a non-invasive intervention to reduce apnea, bradycardia and

  15. Chronic Sarpogrelate Treatment Reveals 5-HT7 Receptor in the Serotonergic Inhibition of the Rat Vagal Bradycardia. (United States)

    García-Pedraza, José Ángel; García, Mónica; Martín, María Luisa; Eleno, Nélida; Morán, Asunción


    5-Hydroxytryptamine (5-HT) modulates the cardiac parasympathetic neurotransmission, inhibiting the bradyarrhythmia by 5-HT2 receptor activation. We aimed to determine whether the chronic selective 5-HT2 blockade (sarpogrelate) could modify the serotonergic modulation on vagal cardiac outflow in pithed rat. Bradycardic responses in rats treated with sarpogrelate (30 mg·kg·d; orally) were obtained by electrical stimulation of the vagal fibers (3, 6, and 9 Hz) or intravenous (IV) injections of acetylcholine (1, 5, and 10 μg/kg). 5-HT7 receptor expression was quantified by Western blot in vagus nerve and right atrium. The IV administration of 5-HT (10-200 μg/kg) dose dependently decreased the vagally induced bradycardia, and agonists 5-CT (5-HT1/7), 8-OH-DPAT (5-HT1A), or AS-19 (5-HT7) (50 μg/kg each) mimicked the 5-HT-induced inhibitory effect. Neither agonists CGS-12066B (5-HT1B), L-694,247 (5-HT1D), nor 1-phenylbiguanide (5-HT3) modified the electrically-induced bradycardic responses. Moreover, SB-258719 (5-HT7 antagonist) abolished the 5-HT-, 5-CT-, 8-OH-DPAT-, and AS-19-induced bradycardia inhibition; 5-HT or AS-19 did not modify the bradycardia induced by IV acetylcholine; and 5-HT7 receptor was expressed in both the vagus nerve and the right atrium. Our outcomes suggest that blocking chronically 5-HT2 receptors modifies the serotonergic influence on cardiac vagal neurotransmission exhibiting 5-HT as an exclusively inhibitory agent via prejunctional 5-HT7 receptor.

  16. Dexmedetomidine is Associated with an Increased Incidence of Bradycardia in Patients with Trisomy 21 After Surgery for Congenital Heart Disease. (United States)

    Ueno, Kentaro; Ninomiya, Yumiko; Shiokawa, Naohiro; Hazeki, Daisuke; Eguchi, Taisuke; Kawano, Yoshifumi


    This study aimed to evaluate adverse cardiac events using dexmedetomidine in infants with trisomy 21 and those without (controls) and examined potential risk factors in infants after cardiovascular surgery. We conducted a single-center retrospective cohort study. The medical records of 124 consecutive infants who had undergone cardiovascular surgery between April 1, 2013, and October 31, 2015, were enrolled. Clinical characteristics, usage of dexmedetomidine, and perioperative medications were analyzed. Adverse cardiac events were assessed with the Naranjo score and World Health Organization-The Uppsala Monitoring Centre (WHO-UMC) criteria. In total, 124 consecutive infants (30 patients and 94 controls) met the inclusion criteria. Eight of 30 (26.7 %) patients with trisomy 21 and 12 of 94 (12.8 %) controls experienced adverse cardiac events (i.e., hypotension, transient hypertension, and bradycardia) during dexmedetomidine with median Naranjo score of 6, and causality categories of WHO-UMC criteria were "certain" or "probable." Of those, the incidence of bradycardia occurred at a higher rate in patients with trisomy 21 than in controls (P = 0.011). Multiple logistic regression analysis revealed that the presence of trisomy 21 was an independent risk factor for adverse cardiac events of dexmedetomidine after cardiovascular surgery (odds ratio 4.10, 95 % CI 1.17-11.19, P = 0.006). Dexmedetomidine is associated with an increased incidence of bradycardia in patients with trisomy 21 after surgery for congenital heart disease. Physicians using dexmedetomidine should know a great deal about the characteristics of patients with trisomy 21, and hemodynamic monitoring should be closely observed.

  17. Atropine sulfate for treatment of bradycardia in a patient with morbid obesity: what may happen when you least expect it. (United States)

    Carron, Michele; Veronese, Stefano


    A 74-year-old morbidly obese man was scheduled for surgical repair of an incisional ventral hernia. Anaesthesia was induced with propofol and fentanyl, and maintained with desflurane. A second dose of fentanyl 0.2 mg, given before starting surgery, resulted in sinus bradycardia and mild decrease of arterial blood pressure. Atropine sulfate 0.5 mg was administered. One minute later, the ECG rhythm on the monitor changed to third degree atrioventricular block with a ventricular response rate of 40 beats/min associated with marked hypotension. Isoproterenol 0.02 mg reverted the atrioventricular block to sinus rhythm. Cardiac enzymes and ECG ruled out acute myocardial ischaemia. The surgical procedure and the recovery from anaesthesia were uneventful. The patient was discharged from the hospital on the fifth postoperative day. For the treatment of bradycardia atropine sulfate should be adjusted at least to lean body weight in order to avoid paradoxical heart rate response in patients with obesity.

  18. Modulation of the vagal bradycardia evoked by stimulation of upper airway receptors by central 5-HT1 receptors in anaesthetized rabbits (United States)

    Dando, Simon B; Skinner, Matthew R; Jordan, David; Ramage, Andrew G


    The effects of central application of 5-HT1A and 5-HT1B/1D receptor ligands on the reflex bradycardia, apnoea, renal sympathoexcitation and pressor response evoked by stimulating upper airway receptors with smoke in atenolol-pretreated anaesthetized rabbits were studied.Intracisternal administration of the 5-HT1A receptor antagonists WAY-100635 (100 μg kg−1) and (−)pindolol (100 μg kg−1) significantly reduced the smoke-induced bradycardia, attenuated the pressor response and in the case of (−)pindolol, sympathetic nerve activity. The same dose of WAY-100635 i.v. was without effect.Buspirone (200 μg kg−1, i.c.) potentiated the reflex bradycardia. This action was prevented if the animals were pretreated with WAY-100635 (100 μg kg−1, i.v.)(+)8-OH-DPAT (25 μg kg−1, i.c.) attenuated the evoked bradycardia, pressor response, apnoea and renal sympathoexcitation. The attenuation of the apnoea and renal sympathoexcitation, but not the bradycardia or pressor response was prevented in animals pretreated with WAY-100635 (100 μg kg−1, i.v.). The attenuation of the reflex bradycardia and the reduction in the renal sympathoexcitation were reduced by pretreatment with the 5-HT1B/1D receptor antagonist GR127935 (100 μg kg−1, i.v.).In WAY-100635 (100 μg kg−1, i.v.) pretreated animals, sumatriptan (a 5-HT1B/1D receptor agonist) reduced the reflex bradycardia and the pressor response. The 5-HT1B/1D receptor antagonist GR127935 (20 μg kg−1, i.c. or 100 μg kg−1, i.v.) had no effect on the reflex responses.In conclusion, the present data are consistent with the hypothesis that activation of central 5-HT1A receptors potentiate whilst activation of 5-HT1B/1D receptors attenuate the reflex activation of cardiac preganglionic vagal motoneurones evoked by stimulation of upper airway receptors with smoke in rabbits. PMID:9786516

  19. Central 5-HT2A receptors modulate the vagal bradycardia in response to activation of the von Bezold-Jarisch reflex in anesthetized rats

    Directory of Open Access Journals (Sweden)

    H.A. Futuro Neto


    Full Text Available Activation of 5-hydroxytryptamine (5-HT 5-HT1A, 5-HT2C, 5-HT3, and 5-HT7 receptors modulates the excitability of cardiac vagal motoneurones, but the precise role of 5-HT2A/2B receptors in these phenomena is unclear. We report here the effects of intracisternal (ic administration of selective 5-HT2A/2B antagonists on the vagal bradycardia elicited by activation of the von Bezold-Jarisch reflex with phenylbiguanide. The experiments were performed on urethane-anesthetized male Wistar rats (250-270 g, N = 7-9 per group. The animals were placed in a stereotaxic frame and their atlanto-occipital membrane was exposed to allow ic injections. The rats received atenolol (1 mg/kg, iv to block the sympathetic component of the reflex bradycardia; 20-min later, the cardiopulmonary reflex was induced with phenylbiguanide (15 µg/kg, iv injected at 15-min intervals until 3 similar bradycardias were obtained. Ten minutes after the last pre-drug bradycardia, R-96544 (a 5-HT2A antagonist; 0.1 µmol/kg, SB-204741 (a 5-HT2B antagonist; 0.1 µmol/kg or vehicle was injected ic. The subsequent iv injections of phenylbiguanide were administered 5, 20, 35, and 50 min after the ic injection. The selective 5-HT2A receptor antagonism attenuated the vagal bradycardia and hypotension, with maximal effect at 35 min after the antagonist (pre-drug = -200 ± 11 bpm and -42 ± 3 mmHg; at 35 min = -84 ± 10 bpm and -33 ± 2 mmHg; P < 0.05. Neither the 5-HT2B receptor antagonists nor the vehicle changed the reflex. These data suggest that central 5-HT2A receptors modulate the central pathways of the parasympathetic component of the von Bezold-Jarisch reflex.

  20. 厌食症合并窦性心动过缓1例%Anorexia with sinus bradycardia:a case report

    Institute of Scientific and Technical Information of China (English)

    王方芳; 徐玲; 陈宝霞; 崔鸣; 张媛


    SUMMARY Asanorexiapatientsalwaysgotothepsychiatricclinic,littleisconcernedabouttheoccur-rence of sinus bradycardia in these patients for cardiologists and psychiatrists.The aim of this paper is to discuss the relationship between anorexia and sinus bradycardia,and the feature analysis,differential diagnosis and therapeutic principles of this type of sinus bradycardia.We report a case of sinus bradycar-dia in an anorexia patient with the clinical manifestations,laboratory exams,auxiliary exams,therapeutic methods,and her prognosis,who was admitted to Peking University Third Hospital recently.The patient was a 1 9-year-old female,who had the manifestation of anorexia.She lost obvious weight in a short time (about 1 5 kg in 6 months),and her body mass index was 1 4.8 kg/m2 .The patient felt apparent palpi-tation,chest depression and short breath,without dizziness,amaurosis or unconsciousness.Vitals on presentation were notable for hypotension,and bradycardia.The initial exam was significant for emacia-tion,but without lethargy or lower extremity edema.The electrocardiogram showed sinus bradycardia with her heart rate being 32 beats per minute.The laboratory work-up revealed her normal blood routine,elec-trolytes and liver function.But in her thyroid function test,the free thyroid (FT)hormones 3 was 0.91 ng/L (2.3-4.2 ng/L),and FT4 was 8.2 ng/L(8.9 -1 8.0 ng/L),which were all lower;yet the thy-roid stimulating hormone(TSH)was normal 1 .48 IU/mL(0.55 -4.78 IU/mL).Ultrasound revealed her normal thyroid.Anorexia is an eating disorder characterized by extremely low body weight,fear of gaining weight or distorted perception of body image,and amenorrhea.Anorexia patients who lose weight appa-rently in short time enhance the excitability of the parasympathetic nerve,and inhibit the sympathetic nerve which lead to the appearance of sinus bradycardia,and functional abnormalities of multiple systems such as hypothyroidism.But this kind of sinus bradycardia and hypothyroidism

  1. Hepatitis B Virus with Sinus Bradycardia%乙型病毒性肝炎致严重窦性心动过缓

    Institute of Scientific and Technical Information of China (English)



    目的:探讨乙型病毒性肝炎(乙肝)致窦性心动过缓的发病机制、临床特征及防治措施。方法对我院收治的乙肝致严重窦性心动过缓1例的临床资料进行回顾性分析。结果本例因食欲缺乏、肝区胀痛9 d 入院,后逐渐出现皮肤、巩膜黄染,伴恶心。入院第5天出现严重窦性心动过缓,行窦房结功能测试示基础状态下窦房结功能低下。鉴于有长期乙肝病史,考虑乙肝致窦性心动过缓。予护肝、降黄、抗病毒等治疗后乙肝得到有效控制,窦性心动过缓症状缓解,病情好转出院。结论乙肝致严重窦性心动过缓临床较少见,了解其发病机制及临床特征可减少误诊误治。%Objective To investigate the clinical features, pathogenesis and prevention of the sinus bradycardia caused by hepatitis B virus. Methods A case of hepatitis B virus with sinus bradycardia in our hospital was retrospectively analyzed. Results The patient was admitted for anorexia, liver area pain for 9 days. Then the jaundice and nausea gradually appeared. 5 days after admission, serious sinus bradycardia appeared. The sinus node function test showed that the patient's sinus node function was low in the basic situation. Because of chronic hepatitis B virus history, the patient was diagnosed as having the sinus bradycardia caused by hepatitis B virus. The hepatitis B virus was controlled after the patient was treated with liver protecting, jaundice reducing and antiviral drugs, and the symptom of sinus bradycardia was also relieved. In the end the patient recovered. Conclusion Hepatitis B virus with sinus bradycardia is uncommon clinically. A good understanding of pathogenesis and clinical features of the disease will help to reduce the rates of misdiagnosis and mistreatment.

  2. Episodes of apnea and bradycardia in the preterm newborn: impact on cerebral oxygenation measured by near-infrared spectrophotometry (United States)

    Van Huffel, Sabine; Craemers, Johan; Lenaerts, Bart; Daniels, Hans; Naulaers, Gunnar; Casaer, Paul


    The objective of this study is to evaluate the effect of episodes of apneas and/or mild bradycardia (heart rate decreases of 10 to 20% or more) on cerebral oxyhemoglobin (HbO2) and reduced hemoglobin (Hb) concentration as measured by Near Infrared Spectrophotometry (NIRS). Measurements were carried out on 7 preterm infants who experienced apneic and bradycardiac events. It is shown how to characterize these events using time-frequency analysis. In addition to NIRS (performed with a NIRO-500 from Hamamatsu, Japan), the heart rate, ECG, peripheral arterial oxygen saturation (measured at the foot) and respiration (abdominal and thoracic pressure, and nasal airflow) were continuously recorded. The impact of apneic events and periodic breathing on these measurements reveals the clinical relevance of NIRS. In particular, we investigate whether these changes in heart rate and respiration also influence HbO2 and reduced Hb concentration in neonatal brain. These changes are characterized, as well as their relationships with the other simultaneously recorded signals such as peripheral arterial oxygen saturation.

  3. Non-expert listeners show decreased heart rate and increased blood pressure (fear bradycardia in response to atonal music

    Directory of Open Access Journals (Sweden)

    Alice Mado eProverbio


    Full Text Available Previous studies suggested that listening to different types of music may modulate differently psychological mood and physiological responses associated with the induced emotions. In this study the effect of listening to instrumental classical vs. atonal contemporary music was examined in a group of 50 non-expert listeners. The subjects’ heart rate and diastolic and systolic blood pressure values were measured while they listened to music of different style and emotional typologies. Pieces were selected by asking a group of composers and conservatory professors to suggest a list of the most emotional music pieces (from Renaissance to present time. A total of 214 suggestions from 20 respondents was received. Then it was asked them to identify which pieces best induced in the listener feelings of agitation, joy or pathos and the number of suggested pieces per style was computed. Atonal pieces were more frequently indicated as agitating, and tonal pieces as joyful. The presence/absence of tonality in a musical piece did not affect the affective dimension of pathos (being touching. Among the most frequently cited six pieces were selected that were comparable for structure and style, to represent each emotion and style. They were equally evaluated as unfamiliar by an independent group of 10 students of the same cohort and were then used as stimuli for the experimental session in which autonomic parameters were recorded. Overall, listening to atonal music (independent of the pieces’ emotional characteristics was associated with a reduced heart rate (fear bradycardia and increased blood pressure (both diastolic and systolic, possibly reflecting an increase in alertness and attention, psychological tension, and anxiety. This evidence fits with the results of the aesthetical assessment showing how, overall, atonal music is perceived as more agitating and less joyful than tonal one.

  4. Non-expert listeners show decreased heart rate and increased blood pressure (fear bradycardia) in response to atonal music. (United States)

    Proverbio, Alice M; Manfrin, Luigi; Arcari, Laura A; De Benedetto, Francesco; Gazzola, Martina; Guardamagna, Matteo; Lozano Nasi, Valentina; Zani, Alberto


    Previous studies suggested that listening to different types of music may modulate differently psychological mood and physiological responses associated with the induced emotions. In this study the effect of listening to instrumental classical vs. atonal contemporary music was examined in a group of 50 non-expert listeners. The subjects' heart rate and diastolic and systolic blood pressure values were measured while they listened to music of different style and emotional typologies. Pieces were selected by asking a group of composers and conservatory professors to suggest a list of the most emotional music pieces (from Renaissance to present time). A total of 214 suggestions from 20 respondents were received. Then it was asked them to identify which pieces best induced in the listener feelings of agitation, joy or pathos and the number of suggested pieces per style was computed. Atonal pieces were more frequently indicated as agitating, and tonal pieces as joyful. The presence/absence of tonality in a musical piece did not affect the affective dimension of pathos (being touching). Among the most frequently cited six pieces were selected that were comparable for structure and style, to represent each emotion and style. They were equally evaluated as unfamiliar by an independent group of 10 students of the same cohort) and were then used as stimuli for the experimental session in which autonomic parameters were recorded. Overall, listening to atonal music (independent of the pieces' emotional characteristics) was associated with a reduced heart rate (fear bradycardia) and increased blood pressure (both diastolic and systolic), possibly reflecting an increase in alertness and attention, psychological tension, and anxiety. This evidence fits with the results of the esthetical assessment showing how, overall, atonal music is perceived as more agitating and less joyful than tonal one.

  5. Non-expert listeners show decreased heart rate and increased blood pressure (fear bradycardia) in response to atonal music (United States)

    Proverbio, Alice M.; Manfrin, Luigi; Arcari, Laura A.; De Benedetto, Francesco; Gazzola, Martina; Guardamagna, Matteo; Lozano Nasi, Valentina; Zani, Alberto


    Previous studies suggested that listening to different types of music may modulate differently psychological mood and physiological responses associated with the induced emotions. In this study the effect of listening to instrumental classical vs. atonal contemporary music was examined in a group of 50 non-expert listeners. The subjects’ heart rate and diastolic and systolic blood pressure values were measured while they listened to music of different style and emotional typologies. Pieces were selected by asking a group of composers and conservatory professors to suggest a list of the most emotional music pieces (from Renaissance to present time). A total of 214 suggestions from 20 respondents were received. Then it was asked them to identify which pieces best induced in the listener feelings of agitation, joy or pathos and the number of suggested pieces per style was computed. Atonal pieces were more frequently indicated as agitating, and tonal pieces as joyful. The presence/absence of tonality in a musical piece did not affect the affective dimension of pathos (being touching). Among the most frequently cited six pieces were selected that were comparable for structure and style, to represent each emotion and style. They were equally evaluated as unfamiliar by an independent group of 10 students of the same cohort) and were then used as stimuli for the experimental session in which autonomic parameters were recorded. Overall, listening to atonal music (independent of the pieces’ emotional characteristics) was associated with a reduced heart rate (fear bradycardia) and increased blood pressure (both diastolic and systolic), possibly reflecting an increase in alertness and attention, psychological tension, and anxiety. This evidence fits with the results of the esthetical assessment showing how, overall, atonal music is perceived as more agitating and less joyful than tonal one. PMID:26579029

  6. Central Anticholinergic Syndrome due to Hypoxia-Induced Bradycardia in a Child with Difficult Intubation Undergoing Complete Dental Restoration: A Case Report. (United States)

    Gharavifard, Mohamad; Razavi, Majid; Ghandehari Motlagh, Mehdi; Ziyaeifard, Mohsen


    Central anticholinergic syndrome (CAS) following general anesthesia (GA) is a well known syndrome in children and adults. Many cases of CAS have been previously reported in the literature. However, there are only two reports of post resuscitation CAS after administration of small doses of atropine. Hereby, we report a case of CAS in a child undergoing complete dental restoration under GA after receiving a small dose of atropine to reverse hypoxia induced bradycardia. Intraoperative events such as hypoxia or cardiac arrest may play a role as triggers for CAS. However, we cannot establish a causal relationship between the occurrence of CAS and such critical events.

  7. Central Anticholinergic Syndrome due to Hypoxia-Induced Bradycardia in a Child with Difficult Intubation Undergoing Complete Dental Restoration: A Case Report.

    Directory of Open Access Journals (Sweden)

    Mohamad Gharavifard


    Full Text Available Central anticholinergic syndrome (CAS following general anesthesia (GA is a well known syndrome in children and adults. Many cases of CAS have been previously reported in the literature. However, there are only two reports of post resuscitation CAS after administration of small doses of atropine. Hereby, we report a case of CAS in a child undergoing complete dental restoration under GA after receiving a small dose of atropine to reverse hypoxia induced bradycardia. Intraoperative events such as hypoxia or cardiac arrest may play a role as triggers for CAS. However, we cannot establish a causal relationship between the occurrence of CAS and such critical events.

  8. 甲状腺功能亢进症心动过缓9例分析%Hyperthyroidism presenting as bradycardia:a report of 9 cases

    Institute of Scientific and Technical Information of China (English)

    赫萍; 赵令君; 史蕴萍


    Objective To report hyperthyroidism also possessing bradycardia. Methods 9 patients with hyperthyroidism were performed thyroid function test,electrocardioagram,holter monitor ECG and the sinoatrial node function test.They are treated with the tapazole. Results All patients heart rate recovered to normol after treatment. Conclusion Hyperthyroidism presenting as bradycardia is related to the sinoatrial node function.%目的了解甲状腺功能亢进症也存在心动过缓的临床表现。方法 9例甲亢患者进行甲状腺功能测定,心电图描记,动态心电图监测,窦房结功能检测,应用抗甲状腺药物治疗。结果经抗甲状腺药物治疗后,心率正常。结论甲亢可影响窦房结功能使其心动过缓。

  9. Relationships between the extent of apnea-induced bradycardia and the vascular response in the arm and leg during dynamic two-legged knee extension exercise. (United States)

    Nishiyasu, Takeshi; Tsukamoto, Rina; Kawai, Katsuhito; Hayashi, Keiji; Koga, Shunsaku; Ichinose, Masashi


    Our aim was to test the hypothesis that apnea-induced hemodynamic responses during dynamic exercise in humans differ between those who show strong bradycardia and those who show only mild bradycardia. After apnea-induced changes in heart rate (HR) were evaluated during dynamic exercise, 23 healthy subjects were selected and divided into a large response group (L group; n = 11) and a small response group (S group; n = 12). While subjects performed a two-legged dynamic knee extension exercise at a work load that increased HR by 30 beats/min, apnea-induced changes in HR, cardiac output (CO), mean arterial pressure (MAP), arterial O(2) saturation (Sa(O(2))), forearm blood flow (FBF), and leg blood flow (LBF) were measured. During apnea, HR in the L group (54 ± 2 beats/min) was lower than in the S group (92 ± 3 beats/min, P leg vascular conductance (LVC), and total vascular conductance (TVC) were all reduced, and MAP was increased in both groups, although the changes in CO, TVC, LBF, LVC, and MAP were larger in the L group than in the S group (P muscle regions.

  10. Inhibitory modulation of chemoreflex bradycardia by stimulation of the nucleus raphe obscurus is mediated by 5-HT3 receptors in the NTS of awake rats. (United States)

    Weissheimer, Karin Viana; Machado, Benedito H


    Several studies demonstrated the involvement of 5-hydroxytryptamine (5-HT) and its different receptor subtypes in the modulation of neurotransmission of cardiovascular reflexes in the nucleus tractus solitarii (NTS). Moreover, anatomic evidence suggests that nucleus raphe obscurus (ROb) is a source of 5-HT-containing terminals within the NTS. In the present study we investigated the possible changes in the cardiovascular responses to peripheral chemoreceptor activation by potassium cyanide (KCN, i.v.) following ROb stimulation with L-glutamate (10 nmol/50 nL) and also whether 5-HT3 receptors in the caudal commissural NTS are involved in this neuromodulation. The results showed that stimulation of the ROb with L-glutamate in awake rats (n=15) produced a significant reduction in the bradycardic response 30 s after the microinjection (-182+/-19 vs -236+/-10 bpm; Wilcoxon test) but no changes in the pressor response to peripheral chemoreceptor activation (43+/-4 vs 51+/-3 mmHg; two-way ANOVA) in relation to the control. Microinjection of 5--HT3 receptors antagonist granisetron (500 pmol/50 nL), but not the vehicle, into the caudal commissural NTS bilaterally prevented the reduction of chemoreflex bradycardia in response to microinjection of L-glutamate into ROb. These data indicate that 5-HT-containing projections from ROb to the NTS play an inhibitory neuromodulatory role in the chemoreflex evoked bradycardia by releasing 5-HT and activating 5-HT3 receptors in the caudal NTS.

  11. 经导管消融治疗心房颤动伴心动过缓%Transcatheter radiofrequency ablation for treatment of atrial fibrillation and bradycardia

    Institute of Scientific and Technical Information of China (English)

    聂晶; 万征; 蔡衡; 张文娟; 于向东; 姚薇; 程晔; 朱可佳


    To evaluate the safety and technique of transcatheter ablation for patients with atrial fibrillation and bradycardia. Methods Twenty-four patients with paroxysmal, persistent or long-standing atrial fibrillation (AF) and bradycardia underwent atrial fibrillation ablation. The procedures included circumferential pulmonary vein isolation, linear atrial ablation and complex fractionated atrial electrogram ablation. The mean and maximum heart rate before and 1 month after ablation were assessed by 24-hour ambulatory monitoring. Left atrium size was evaluated by echocardiography 6 months after ablation. Results After AF ablation, the mean heart rate and maximum heart rate were higher than before (all P<0. 001) , and left atrium size decreased at 6 months (P<0. 001). During 19. 8±9. 9 months' follow-up, 15 patients (15/24, 62. 50%) had no recurrence of AF nor symptoms attributable to bradycardia, 6 patients had infrequent episodes of atrial tachycardia or premature atrial contraction, 1 patient required pacemaker implantation, and 2 patients had infrequent attacks of AF. Conclusion Prolonged sinus pauses and bradycardia after paroxysms of AF together with some tachycardia-bradycardia syndrome may be resulted from depression of sinus node function that can be eliminated by curative ablation of AF. For patients in this situation, transcatheter radiofrequency ablation may be used to safely and effectively improve sinus node function and reverse remodeling of the sinus node.%目的 探讨经导管消融治疗心房颤动合并心动过缓的方法和患者的安全性.方法 对24例心房颤动伴心动过缓患者行经导管消融治疗心房颤动,消融策略包括环肺静脉电隔离、左心房线性消融及复杂心房碎裂电位( CFAE)消融.观察消融前及术后1个月动态心电图,并记录24h平均心率、最高窦性心率,以超声心动图评价术后6个月左心房直径变化.结果 心房颤动消融术后患者平均心率、最高

  12. Hemodialysis-refractory metformin-associated lactate acidosis with hypoglycemia, hypothermia, and bradycardia in a diabetic patient with belated diagnosis and chronic kidney disease
. (United States)

    Zibar, Lada; Zibar, Karin


    Metformin is a first-line oral antidiabetic therapy for patients with type 2 diabetes mellitus. Metformin-associated lactate acidosis (MALA) is a well-known, life-threatening, but rare side effect of metformin therapy. Chronic kidney disease (CKD) patients have a much greater risk of MALA. We report the case of a severe refractory MALA despite hemodialysis (HD) treatment, associated with hypoglycemia, hypothermia, and bradycardia in a neglected and thus untimely-recognized CKD patient with type 2 diabetes mellitus. Despite the recent rehabilitation of metformin as a treatment of choice for type 2 diabetes mellitus, the drug should be prescribed with caution as it can be associated with life-threatening refractory acidosis, particularly in CKD patients. Moreover, HD treatment could occasionally be ineffective, resulting in a fatal outcome.

  13. Nociceptin/orphanin FQ (N/OFQ)-evoked bradycardia, hypotension, and diuresis are absent in N/OFQ peptide (NOP) receptor knockout mice. (United States)

    Burmeister, Melissa A; Ansonoff, Michael A; Pintar, John E; Kapusta, Daniel R


    Intracerebroventricular administration of the opioid-like peptide nociceptin/orphanin FQ (N/OFQ) produces bradycardia, hypotension, and diuresis in mice. We hypothesized that these responses are solely caused by selective activation of central N/OFQ peptide (NOP) receptors. To test this premise, we first examined whether i.c.v. N/OFQ produced dose-dependent diuretic and cardiovascular depressor responses in commercially available C57BL/6 mice. Next, using doses established in these studies, we examined the renal excretory and cardiovascular responses to i.c.v. N/OFQ in conscious transgenic NOP receptor knockout mice (NOP(-/-)). In metabolic studies, i.c.v. N/OFQ, but not saline vehicle, dose-dependently increased urine output (V) in NOP(+/+); this response was significant at 3 nmol (N/OFQ, V = 0.39 +/- 0.10 ml/2 h; saline, 0.08 +/- 0.05 ml/2 h). The N/OFQ-evoked diuresis was absent in littermate NOP(-/-) (N/OFQ, V = 0.06 +/- 0.06 ml/2 h; saline, 0.03 +/- 0.03 ml/2 h). There were no significant changes in urinary sodium or potassium excretion or free water clearance in either group. In telemetry studies, i.c.v. N/OFQ dose dependently lowered heart rate (HR) and mean arterial pressure (MAP). At 3 nmol N/OFQ, both HR and MAP were reduced in NOP(+/+) (peak DeltaHR = -217 +/- 31 bpm; peak DeltaMAP =-47 +/- 7 mm Hg) compared with saline (peak DeltaHR =-14 +/- 5 bpm; peak DeltaMAP = 2 +/- 3 mm Hg). These N/OFQ-evoked bradycardic and hypotensive responses were absent in NOP(-/-) (peak DeltaHR =-13 +/- 17 bpm; peak DeltaMAP =-2 +/- 4 mm Hg, respectively). Basal 24-h cardiovascular and renal excretory function were not different between NOP(-/-) and NOP(+/+) mice. These results establish that the bradycardia, hypotension and diuresis produced by centrally administered N/OFQ are mediated by selective activation of NOP receptors.

  14. Circadian rhythm of heart rate in the rabbit: prolongation of action potential duration by sustained beta adrenoceptor blockade is not due to associated bradycardia. (United States)

    Vaughan Williams, E M; Dennis, P D; Garnham, C


    Six litters of six young rabbits were injected intraperitoneally, two per litter, with saline, alinidine, or nadolol once or twice daily for two weeks. In four litters successful radiotransmissions of electrocardiograms were recorded once hourly for four days before and during treatment. Alinidine and nadolol produced an overall mean bradycardia in comparison with saline treated animals, the effect of alinidine exceeding that of nadolol. At 48-70 hours after the end of treatment the hearts were used for in vitro electrophysiological study. Nadolol, but not alinidine, induced a prolongation of action potential duration compared with that of saline treated littermates in both atrial and ventricular muscle. An incidental observation was that heart rate in the rabbit followed a circadian rhythm, heart rates being slower in the morning and faster in late afternoon and evening. The circadian rhythm was attenuated but not abolished by alinidine and nadolol. These results suggest that if prolongation of action potential duration by sustained beta blockade in patients after myocardial infarction contributes to protection against sudden death (by a class III antiarrhythmic action) then alinidine would not be expected to provide a comparable prophylaxis.

  15. Junctional Bradycardia as Early Sign of Digoxin Toxicity in a Premature Infant with Congestive Heart Failure due to a Left to Right Shunt. (United States)

    Dasgupta, Soham; Aly, Ashraf M; Jain, Sunil K


    Introduction Congestive heart failure due to left to right cardiac shunt is usually managed medically with diuretics, angiotensin converting enzyme inhibitors, and, in some cases, with the addition of digoxin. Case We report a 31-week gestation premature male infant who did not respond to such treatment and developed hyperaldosteronism and severe hypokalemia secondary to activation of the renin angiotensin aldosterone system. The hypokalemia was not responsive to intravenous KCL supplementation and induced digoxin toxicity despite a relatively normal digoxin level. The earliest signs of digoxin toxicity in the patient were junctional rhythm and bradycardia. The discontinuation of digoxin and the administration of digoxin specific immunoglobulin fragments (Fab) reversed those changes. The addition of spironolactone (an aldosterone antagonist) had a dramatic effect, resulting in clinical improvement of the patient coupled with normalization of Q4 serum and urine electrolytes. Conclusion Serum Digoxin level alone may fail as an independent guide in the diagnosis of digoxin toxicity when hypokalemia is present. In premature infants with congestive heart failure and hypokalemia, addition of an aldosterone antagonist should be considered.

  16. The effect of O2 and CO2 on the dive behavior and heart rate of lesser scaup ducks (Aythya affinis): quantification of the critical PaO2 that initiates a diving bradycardia. (United States)

    Borg, Kim A; Milsom, William K; Jones, David R


    Lesser scaup ducks were trained to dive for short and long durations following exposure to various gas concentrations to determine the influence of oxygen (O2) and carbon dioxide (CO2) on diving behavior and heart rate. Compared with normoxia, hyperoxia (50% O2) significantly increased the duration of long dives, whereas severe hypoxia (9% O2) significantly decreased the duration of both short and long dives. Hypercapnia (5% CO2) had no effect on dive duration. Surface intervals were not significantly altered by the oxygen treatments, but significantly increased following CO2 exposure. Heart rate during diving was unaffected by hyperoxia and hypercapnia, but gradually declined in long dives after severe hypoxia. Thus, our results suggest that during the majority of dives, O2 and CO2 levels in lesser scaup ducks are managed through changes in diving behavior without any major cardiovascular adjustments, but below a threshold PaO2, a bradycardia is evoked to conserve the remaining oxygen for hypoxia sensitive tissues. A model of oxygen store utilization during voluntary diving was developed to estimate the critical PaO2 below which bradycardia is initiated (approximately 26 mmHg) and predicted that this critical PaO2 would be reached 19s into a dive after exposure to severe hypoxia, which corresponded exactly with the time of initiation of bradycardia in the severe hypoxia trials.

  17. 用生物学方法重建心脏起搏点的研究进展%Biological approaches to generating cardiac biopacemaker for bradycardia

    Institute of Scientific and Technical Information of China (English)

    萧永福; DanielC.Sigg


    Normal rhythm in a healthy human heart originates from the natural biological pacemaker, the sinoatrial (SA) node which locates in the right atrium. SA node dysfunction or atrial-ventricular (AV) conduction block causes improper heart rate (bradycardia).Such dysfunction, if severe enough, is currently treated by implanting an electronic pacemaker which has been well established technically, but there are some limitations and inadequacies. Recently, progress in developing engineered cardiac biopacemakers with use of genes or cells has been made in experimental animal models. The hyperpolarization-activated cyclic-nucleotide-modulated(HCN) channel (pacemaker channel) modulates cardiac automaticity via the hyperpolarization-activated cation current (If). HCN genes have been delivered to animal myocardium via viral vectors or HCN-transferred cells for recreating biological pacemakers. Approaches with non-HCN genes or transplantation of beating cells are also novel and have been investigated for generating cardiac biopacers. This article summarizes the progresses in research on recreation of cardiac biopacemakers. Genetically engineered biological pacemaker holds great promise to potentially cure severe bradycardia if critical issues, such as their stability and longevity, are properly solved.%正常人的心脏节律源于右心房的天然起搏点(pacemaker)--窦房结.窦房结的功能异常或者房室传导阻滞会导致心率异常(如心律缓慢).治疗严重的心动过缓需要植入在技术上已经相当成熟的电子起搏器,但这种治疗存在一些缺陷和不足.近年来,在动物实验模型中应用基因或细胞来重建心脏的生物起搏点已经取得了进展.超极化活化环核苷酸门控(hyperpolarization-activated cyclic-nucleotide-modulated,HCN)通道(起搏通道)通过超极化活化的阳离子电流(hyperpolarization-activated cation current,If)调制心脏的自律性.利用病毒载体或转染HCN基因的细胞将HCN基

  18. Frequency of apnea, bradycardia, and desaturations following first diphtheria-tetanus-pertussis-inactivated polio-Haemophilus influenzae type B immunization in hospitalized preterm infants

    Directory of Open Access Journals (Sweden)

    Spady Donald W


    Full Text Available Abstract Background Adverse cardiorespiratory events including apnea, bradycardia, and desaturations have been described following administration of the first diphtheria-tetanus-pertussis-inactivated polio-Haemophilus influenzae type B (DTP-IPV-Hib immunization to preterm infants. The effect of the recent substitution of acellular pertussis vaccine for whole cell pertussis vaccine on the frequency of these events requires further study. Methods Infants with gestational age of ≤ 32 weeks who received their first DTP-IPV-Hib immunization prior to discharge from two Edmonton Neonatal Intensive Care Units January 1, 1996 to November 30, 2000 were eligible for the study. Each immunized infant was matched by gestational age to one control infant. The number of episodes of apnea, bradycardia, and/or desaturations (ABD and the treatment required for these episodes in the 72 hours prior to and 72 hours post-immunization (for the immunized cohort or at the same post-natal age (for controls was recorded. Results Thirty-four infants who received DTP-IPV-Hib with whole cell pertussis vaccine, 90 infants who received DTP-IPV-Hib with acellular pertussis vaccine, and 124 control infants were entered in the study. Fifty-six immunized infants (45.1% and 36 control infants (29.0% had a resurgence of or increased ABD in the 72 hours post-immunization in the immunized infants and at the same post-natal age in the controls with an adjusted odds ratio for immunized infants of 2.41 (95% CI 1.29,4.51 as compared to control infants. The incidence of an increase in adverse cardiorespiratory events post-immunization was the same in infants receiving whole cell or acellular pertussis vaccine (44.1% versus 45.6%. Eighteen immunized infants (14.5% and 51 control infants (41.1% had a reduction in ABD in the 72 hours post- immunization or at the equivalent postnatal age in controls for an odds ratio of 0.175 (95%CI 0.08, 0.39. The need for therapy of ABD in the immunized

  19. Bradicardia como manifestação epiléptica em epilepsia temporal: relato de caso Bradycardia during temporal lobe seizure: case report

    Directory of Open Access Journals (Sweden)



    Full Text Available Descrevemos um caso de arritmia cardíaca como manifestação epiléptica. A monitorização video-eletrencefalográfica de uma paciente com 34 anos de idade que apresentava episódios de perda de consciência permitiu a detecção de períodos de assistolia como principal manifestação clínica, exigindo a implantação de marca-passo. O registro eletrencefalográfico concomitante mostrou atividade rítmica a 6-7 Hz de projeção na região temporal esquerda. A ressonância magnética mostrou lesão expansiva no giro para-hipocampal esquerdo. Alterações do ritmo cardíaco como taquicardia sinusal são frequentes em crises epilépticas. A descrição de bradicardia e/ou assistolia é rara. As conexões das estruturas mesiais temporais com estruturas profundas como o hipotálamo devem ser responsáveis pelas manifestações vegetativas durante crises epilépticas temporais.We describe a patient who had cardiac arrhythmia as epileptic manifestation. In a 34-year-old woman who had many episodes of loss of consciousness, the simultaneous ECG and video-EEG monitoring recorded bradycardia with a short episode of asystolia (4 seconds and left temporal rhythmic teta activity on EEG. MRI showed a small mass lesion in the left parahippocampal gyrus. Alterations in cardiac rhythm have been reported in epileptic seizures and taquycardia is the most common finding associated with them; bradyarrhythmia during seizures was uncommon. Many interconnections among insular cortex, limbic system and hypothalamus, may be responsible for vegetative manifestations in temporal lobe epilepsy.

  20. The clinically-tested S1P receptor agonists, FTY720 and BAF312, demonstrate subtype-specific bradycardia (S1P₁ and hypertension (S1P₃ in rat.

    Directory of Open Access Journals (Sweden)

    Ryan M Fryer

    Full Text Available Sphingosine-1-phospate (S1P and S1P receptor agonists elicit mechanism-based effects on cardiovascular function in vivo. Indeed, FTY720 (non-selective S1P(X receptor agonist produces modest hypertension in patients (2-3 mmHg in 1-yr trial as well as acute bradycardia independent of changes in blood pressure. However, the precise receptor subtypes responsible is controversial, likely dependent upon the cardiovascular response in question (e.g. bradycardia, hypertension, and perhaps even species-dependent since functional differences in rodent, rabbit, and human have been suggested. Thus, we characterized the S1P receptor subtype specificity for each compound in vitro and, in vivo, the cardiovascular effects of FTY720 and the more selective S1P₁,₅ agonist, BAF312, were tested during acute i.v. infusion in anesthetized rats and after oral administration for 10 days in telemetry-instrumented conscious rats. Acute i.v. infusion of FTY720 (0.1, 0.3, 1.0 mg/kg/20 min or BAF312 (0.5, 1.5, 5.0 mg/kg/20 min elicited acute bradycardia in anesthetized rats demonstrating an S1P₁ mediated mechanism-of-action. However, while FTY720 (0.5, 1.5, 5.0 mg/kg/d elicited dose-dependent hypertension after multiple days of oral administration in rat at clinically relevant plasma concentrations (24-hr mean blood pressure = 8.4, 12.8, 16.2 mmHg above baseline vs. 3 mmHg in vehicle controls, BAF312 (0.3, 3.0, 30.0 mg/kg/d had no significant effect on blood pressure at any dose tested suggesting that hypertension produced by FTY720 is mediated S1P₃ receptors. In summary, in vitro selectivity results in combination with studies performed in anesthetized and conscious rats administered two clinically tested S1P agonists, FTY720 or BAF312, suggest that S1P₁ receptors mediate bradycardia while hypertension is mediated by S1P₃ receptor activation.

  1. Dynamic ECG analysis of tumor patients with heartbeat sinus bradycardia before operation%窦性心动过缓肿瘤患者术前动态心电图分析

    Institute of Scientific and Technical Information of China (English)

    冯保华; 程俊录; 高琳


    Objective:To investigate the presence of sick sinus syndrome(SSS) of tumor patients with heartbeat sinus bradycardia before operation,so as not to increase the risk of operation in patients with tumors.Methods:Tumor patients with heartbeat sinus bradycardia in routine electrocardiogram before operation were selected.They were given 24 hours dynamic electrocardiogram(DCG) detection.The DCG data of patients were divided into two groups,less than 60 years for the A group, greater than or equal to 60 years for the B group.We compared the dynamic ECG data.Results:Real property,borderline, ventricular premature beats,paroxysmal atrial tachycardia and beckoning long R-R interval of the two groups had significant difference(P<0.05),and in the two groups,the detection rate of paroxysmal supraventricular tachycardia,atrial fibrillation,sinus arrest,sinoatrial conduction block in the patients with heart rate from 50 to 59 times/minute were significantly lower than the patients with heart rate of less than 50 times/minute.Conclusion:With the increase of age,sinus bradycardia beckoning was increased;the conventional ECG showed sinus bradycardia with heart rate from 50 to 59 times/minute was physiologic;the detection rate of SSS in patients with sinus bradycardia with heart rate of less than 50 times/minute was increased.For sick sinus syndrome patients,before operation,protection of temporary pacemaker was installed best,to prevent accidents in the operation of heart.%目的:探讨肿瘤患者术前窦性心动过缓者是否存在病态窦房结综合征(SSS),以免增加肿瘤患者的手术风险。方法:选择术前常规心电图中窦性心动过缓的肿瘤患者进行24 h动态心电图(DCG)检测,并把患者的DCG资料分为两组,<60岁为A组,≥60岁为B组,对比两组患者的动态心电图资料。结果:两组患者的房性、交界性、室性期前收缩、短阵性房性心动过速及长R-R间期差异有统计学意义(P<0.05)

  2. 脊髓损伤康复期患者窦性心动过缓调查及治疗策略探讨%Survey and treatment strategy on sinus bradycardia of patients with spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    雒生杰; 李建军; 李寿霖


    目的:通过病例回顾性调查来了解脊髓损伤患者窦性心动过缓的发生率,探讨这一特殊人群可能的心律失常风险及治疗策略.方法:对中国康复研究中心2004年1月~2009年12月年因脊髓损伤入院进行康复治疗的1 831例患者(男1 470例,女361例)进行入院后静息心电图调查,并记录心率及心律失常类型.结果:颈脊髓损伤患者平均心率显著低于胸腰段脊髓损伤患者(男:67次/min vs 74次/min,女:67次/min vs 76次/min,P<0.01),窦性心动过缓发生率显著升高(男:34% vs 10%,女:29% vs 8%,P<0.01).结论:脊髓损伤康复期患者中,窦性心动过缓主要发生于颈脊髓损伤患者.目前长期药物治疗效果尚不清楚,对难治性、持续性严重心动过缓者起搏器治疗可能是有益的选择.需要进一步循证医学证据支持.%Objective: To investigate on sinus bradycardia of patients with spinal cord injury (SCI) and try to find the possible risk and therapeutic strategy for them.Methods: ECG characteristics of 1 831 chronic SCI patients (including 1 470 men and 361 women) for rehabilitation therapy in China Rehabilitaion Research Center (CRRC) from January 2004 to December 2009 were investigated, their heart rate and the type of arrhythmia were recorded.Results: The heart rates of patients with cervical spinal cord injury (CSCI) were lower than that of the patients with thoracic and lumbar SCI (T&LSCI) (men: 67 times per minutes vs 74 times per minutes, women: 67 times per minutes s 76 times per minutes, P<0.01), the rate of sinus bradycardia (men: 34% vs 10%, women: 29% vs 8%, P<0.01) were higher than those with thoracic and lumbar SCI (T&LSCI).Conclusion: Patients with CSCI showed significantly higher prevalence of sinus bradycardia than those with T&LSCI.Long term effects of medical treatment for the patients are unclear.Permanent cardiac pacemaker should be strongly considered in severe patients with refractory or recurrent

  3. 瓣膜置换术后窦性心动过缓VVI与DDD起搏的随访观察%The follow-up observation for VVI and DDD pacing in sinus bradycardia after valve replacement

    Institute of Scientific and Technical Information of China (English)

    陈敏; 李莉; 徐志云


    Objective To compare the clinical effects of VVI and DDD pacing in sinus bradycardia in patients after valve replacement. Methods All 29 patients with sinus bradycardia after valve replacement were divided into 2 groups by different pacing-mode:DDD group(n = 17) ,VVI group(n = 12). The changes of left ventricular ejection fraction, fractional shortening and the size of atrial ventricular, the occurrence of permanence atrial fibrillation(AF) , the hospitalization for heart failure, the stroke and the death were followed up. Results Mean follow-up was 28 months; All patients had no complications in pacemaker implantation. There was none of stroke and death during the follow-up period. The incidence rate of permanence AF in DDD group was significantly lower than that in VVI group; The hospitalization rate for heart failure in DDD group was significantly lower than that in VVI group . The left atrial volume and diameter in VVI group was significantly increased compared with baseline,but which were not significantly increased in DDD group; The ejection fraction in VVI group was lower than that in DDD group( 0.57 ± 0.08 vs 0.63 ± 0.10, P < 0.05 ). Conclusion Compare to VVI pacing,DDD pacing gets the lower ratio of permanent AF, the lower ratio of the hospitalization for heart failures and improves the cardiac remodelling and function in patients who have sinus bradycardia after valve replacement. [ Chinese Journal of Cardiac Pacing and Electrophyswlogy,2011,25(4) :313 -315]%目的 探讨VVI与DDD起搏对瓣膜置换术后窦性心动过缓患者疗效的差异.方法 瓣膜置换术后窦性心动过缓患者29例,按不同起搏方式分为:DDD组(n=17例),VVI组(n=12例),观察左室射血分数,短轴缩短率,心房心室变化,永久性心房颤动(简称房颤),卒中,心力衰竭(简称心衰)住院,死亡的发生.结果 两组患者均未发生起搏器安置术并发症,在平均随访28个月,未发生卒中、死亡.

  4. 心房颤动射频消融术后新近发生的显著心动过缓病因及处理%New onset of significant bradycardia after catheter ablation for atrial fibrillation——causes and strategy of management

    Institute of Scientific and Technical Information of China (English)

    张劲林; 唐成; 张勇华; 韩宏伟; 李振; 李继文; 蒋萍; 程光辉; 邓成刚


    目的 探讨心房颤动(房颤)导管射频消融术后新近发生的显著心动过缓的病因及处理对策.方法 连续1287例接受导管消融的房颤患者中共21例(阵发性房颤13例,持续性房颤8例)在术后新出现显著的心动过缓(窦性停搏时间>5 s或平均心率<50次/min).结果 13例阵发性房颤术后均频繁发作房性心律失常,并在终止时出现长窦性停搏现象,13例均接受了2次手术,平均随访(18.8±9.2)个月,12例无房性心律失常复发,也没有窦性停搏或心动过缓的表现和症状.1例仍有房性心律失常复发植入永久起搏器治疗.8例持续性房颤首次消融术后均出现严重窦性心动过缓(7/8)或房性心律失常终止时的窦性停搏(5/8),观察1~2周无改善后均植入永久起搏器治疗.结论 阵发性房颤消融术后出现长窦性停搏多数和房性心律失常复发相关,通过再次消融成功治愈的把握较大,而持续性房颤消融术后出现的严重心动过缓病因复杂,永久起搏器植入可能是首选.%Objective To investigate the causes and strategy of management of new onset of significant bradycardia after catheter ablation for atrial fibrillation (AF).Methods Twenty-one patients (13 paroxysmal and 8 persistent AF)out of 1287 consecutive AF patients who underwent catheter ablation(prevalence 1.6%)developed significant bradycardia (sinus pauses >5 seconds or average heart rate<50 beats/minute)after the procedure.Results Thirteen patients with paroxysmal AF developed prolonged sinus pauses on termination of recurrent atrial tachyarrhythmias (AT) after initial ablation,all of them accepted reablation procedure.During (18.8±9.2)months follow-up,12 patients had no recurrence of AF,with no symptoms attributable to bradycardia or sinus pauses,and one patients still had infrequent episodes of AT requiring pacemaker implantation.After the initial procedure,8 patients with persistent AF developed significant sinus

  5. 炙桂枝与肉桂对普萘洛尔致心动过缓大鼠Na+-K+-ATP酶活性研究%Effect of prepared cassia twigs and cassia on Na+-K+-ATPase activity in rats with bradycardia caused by propranolol

    Institute of Scientific and Technical Information of China (English)

    罗琳; 陈一江


    Objective:To study effect of prepared cassia twigs and cassia on Na +-K +-ATPase activity in rats with bradycardia caused by propranolol. Methods:70 rats were randomly divided into prepared cassia twig group,prepared cassia twig model group,cassia group,cassia model group,blank group,propranolol group and atropine group (n=10). Model rats were constructed by propranolol.7 d after treatment,heart rate and activity of Na+-K+-ATPase were observed. Results:Compared with propranolol group,the drop rate of 30 min heart rate was decreased in prepared cassia twig model group and cassia model group (P<0.01). The activity of Na+-K+-ATPase in prepared cassia twig model group and cassia model group was higher than that in propranolol group(P<0.05,P<0.01). Conclusion:Both prepared cassia twig and cassia can obviously increase the heart rate in bradycardia rats caused by propranolol through improving the activity of Na+-K+ATpase.%目的:比较炙桂枝与肉桂对普萘洛尔所致心动过缓大鼠心率及Na+-K+-ATP酶活性的影响,分析炙桂枝与肉桂在抗心动过缓中的作用机制及两者差异。方法:将70只大鼠随机分为炙桂枝组、炙桂枝模型组、肉桂组、肉桂模型组、空白组、普萘洛尔模型对照组,每组10只。连续给药7 d,以普萘洛尔造模,比较各组大鼠心率变化及Na+-K+-ATP酶活性。结果:炙桂枝组与肉桂组30 min心率减慢变化率较普萘洛尔模型对照组明显升高(P<0.01);炙桂枝模型组、肉桂模型组Na+-K+-ATP酶活性较普萘洛尔模型对照组高(P<0.01)。结论:炙桂枝与肉桂均能显著提高普萘洛尔致心动过缓的大鼠的Na+-K+-ATP酶活性,以增加心率。

  6. Elderly Sinus Bradycardia in Patients with Dynamic ECG and Transesophageal Atrial Pacing in the Determination of the Evaluation of Sinus node Function%老年窦性心动过缓患者应用动态心电图与经食管心房调搏测定窦房结功能的评价

    Institute of Scientific and Technical Information of China (English)



      目的:评价动态心电图与经食管心房调搏对老年窦性心动过缓患者进行窦房结功能测定的价值。方法:对84例常规心电图诊断为窦性心动过缓的老年患者,行动态心电图检查,根据患者动态心电图R-R最长间期是否>2s,分为R-R最长间期≥2s组和R-R最长间期 2s, divided into RR longest interval ≥ 2s group and RR longest interval <2s group, the above two groups of patients by transesophageal atrial pacing and related indicators of the two checks for statistical analysis. Results:ambulatory electrocardiogram RR longest of≥2s group and<2s-group comparison of sinus node recovery time (SNRT), corrected sinus node recovery time (CSNRT), sinoatrial conduction time (SACT) was significantly prolonged, the most fast heart rate and the slowest heart rate was significantly lower, transesophageal atrial pacing CSNRT and SACT ambulatory electrocardiogram longest RR interval, respectively, the fastest heart rate, the slowest heart rate, there is a significant positive correlation. Conclusion: Dynamic ECG and transesophageal atrial pacing checks can better reflect the sinus node function, transesophageal atrial pacing CSNRT SACT and dynamic ECG longest R-R interval, the fastest heart rate, the slowest heart rate between obvious;for elderly patients with sinus bradycardia, dynamic ECG longest R-R interval, the fastest heart rate, the slowest heart rate on sinus node function screening.

  7. Selective ablation of sinoatrial and atrioventricular nodal peripheral nerve to treat bradycardia:spectral analysis of heart rate fluctuation%选择性消融窦房与房室结周神经治疗缓慢性心律失常的心率波动频谱分析研究

    Institute of Scientific and Technical Information of China (English)

    郝蓬; 李果; 何东方; 卢春山; 郭成军; 刘兴鹏; 柳景华; 张英川; 方东平; 赵东辉; 刘冰; 王国忠


    目的 探讨动态心电图心率波动频谱分析对选择性消融窦房结与房室结周围神经治疗缓慢性心律失常患者的作用.方法 选择症状严重、拟行起搏器治疗的阵发性心动过缓患者35例,术前行动态心电图检查并进行心率波动频谱分析.对于症状及频谱分析支持心动过缓为迷走神经张力增高所致的患者,在X线与64排螺旋CT心脏解剖影像指导下,标测实性心律下的心房激动顺序,围绕并避开心房最早激动点和His束区域,记录心内电图神经组织电位,温控射频消融,观察消融反应,随访治疗效果.结果 成功的30例患者中,28例高频成分(HF)明显,低频成分(LF)存在;2例为LF缺失,HF明显.复发的5例患者中4例为LF缺失,HF明显;1例为HF明显,LF存在.术后动态心电图检查,成功的30例患者中17例HF明显降低,余无明显变化.复发的5例患者中1例HF明显降低,余无明显变化.电生理检查显示,消融后患者基础心率、SNRT、WP、AH间期都得到了明显改善(P<0.01).结论 对于心率波动频谱分析支持心动过缓系由迷走神经张力增高所致的患者,选择性消融窦房结或房室结周围神经有较好治疗效果.%Objective To analyze of the heart rate fluctuation in selective ablation of sinoatrial and atrioventricular nodal peripheral nerve in treating patients with bradyarrhythmias. Methods Holter preoperative examination and spectral analysis of heart rate fluctuations were performed in selective patients with severe symptoms, scheduled for the treatment of paroxysmal bradycardia using pacemaker. For patients in whom the vagal bradycardia was suggested by the symptoms and spectrum analysis,ablation of sinoatrial and atrioventricular nodal peripheral nerve was performed under of the mapping atrial activation sequence during sinus rhythm combined with X-ray and 64-slice spiral CT imaging cardiac anatomy. The target sites were around but away from the first

  8. Chest compressions for bradycardia or asystole in neonates. (United States)

    Kapadia, Vishal; Wyckoff, Myra H


    When effective ventilation fails to establish a heart rate of greater than 60 bpm, cardiac compressions should be initiated to improve perfusion. The 2-thumb method is the most effective and least fatiguing technique. A ratio of 3 compressions to 1 breath is recommended to provide adequate ventilation, the most common cause of newborn cardiovascular collapse. Interruptions in compressions should be limited to not diminishing the perfusion generated. Oxygen (100%) is recommended during compressions and can be reduced once adequate heart rate and oxygen saturation are achieved. Limited clinical data are available to form newborn cardiac compression recommendations.

  9. Glycopyrrolate prevents extreme bradycardia and cerebral deoxygenation during electroconvulsive therapy

    DEFF Research Database (Denmark)

    Rasmussen, Peter; Andersson, John-Erik; Koch, Palle


    .8) to 0.0 (-4.2 to 0.8) microM (P largely eliminated these effects during the stimulation phase of ECT, maintaining HR at 78 (40-94) beats min(-1), MCA V(mean) at 53 (37-77) cm s(-1), and O(2)Hb at 5.6 (10.6-38.5) microM (P

  10. Fear bradycardia and activation of the human periaqueductal grey

    NARCIS (Netherlands)

    Hermans, E.J.; Henckens, M.J.A.G.; Roelofs, K.; Fernandez, G.S.E.


    Animal models of predator defense distinguish qualitatively different behavioral modes that are activated at increasing levels of predation threat. A defense mode observed at intermediate threat levels is freezing: a cessation of locomotion that is characterized by a parasympathetically dominated au

  11. Effects of co-administration of aminophylline and atropine on bradycardia treatment in patients undergoing ;cardiac valve replacement%氨茶碱与阿托品联合应用对心脏瓣膜置换术患者心动过缓的治疗作用

    Institute of Scientific and Technical Information of China (English)

    高明涛; 周锦; 陈克研; 张铁铮; 王长英


    #目的探讨氨茶碱和阿托品联合应用在心脏瓣膜置换术中对患者心动过缓的治疗作用。方法选取在心脏瓣膜置换术中,体外循环停止、复跳5 min后发生心动过缓(心率<50次/min )患者90例,按美国麻醉师协会标准分级( ASA)Ⅱ~Ⅲ级,随机分为三组:A组30例,首次静注阿托品0.5 mg,无效则每5 min追加阿托品1 mg;B组30例,首次静注阿托品1 mg,无效则每5 min追加阿托品1 mg;C组30例,首次联合静注阿托品0.5 mg和氨茶碱0.125 g,无效则以相同剂量静注追加。观察并记录三组患者术中心律失常和术后恶心、呕吐等不良反应的发生情况,比较药物的平均作用剂量,分析三组的治疗有效率。结果三组患者ASA分级、体重、心功能等一般情况差异不显著( P>0.05)。 C组治疗有效率(90.00%)明显高于A组(46.67%)和B组(53.33%)(χ2=14.10,P<0.05)。 C组阿托品平均作用剂量为(0.86±0.17)mg,低于A组(1.83±0.12)mg和B组(1.79±0.45)mg(q=6.91、7.62,P均<0.05)。 C组不良反应发生情况明显低于A组和B组(χ2=4.05,P<0.05)。结论氨茶碱和阿托品联合应用对心脏瓣膜置换手术患者心动过缓具有很好的治疗作用,可有效地提高治愈率,降低毒副反应,提高麻醉安全性。%Objective To investigate bradycardia treatment effects of co-administration of aminophylline and atropine in patients undergoing cardiac valve replacement with cardiopulmonary bypass (CPB).Methods When five minute after stopping CPB , ninety patients with cardiac valve replacement were randomly divided into three groups:Group A:30 patients were infused intravenously 0.5 mg atropine in the first place .Atropine 1 mg would be added every five minute if ineffective .Group B:30 patients were infused intravenously 1 mg atropine in the first place . Atropine 1 mg would be added every five minute if

  12. 快慢综合征心房颤动患者射频消融术后心率及窦房结功能的变化%Changes of heart rate and sinus node function after radiofrequency ablation of paroxymal atrial fibrillation in patients with tachycardia-bradycardia syndrome

    Institute of Scientific and Technical Information of China (English)

    时向民; 王玉堂; 单兆亮; 赵立朝; 杨庭树


    目的 观察快慢综合征心房颤动患者射频消融治疗后心率的变化,探讨心房颤动对窦房结功能的影响,以及心房颤动治愈后窦房结功能的恢复情况.方法 16例动态心电图显示心房颤动终止后伴有窦性停搏[最长间歇(MRRI) >3 s]的阵发性心房颤动患者,在CARTO系统指导下进行电隔离消融,术后1周及3个月分别行24h动态心电图检查,观察MRRI>2 s的次数(NP>2 s)、最慢心率(MIHR)、最快心率(MAHR)、平均心率(MEHR)以及患者临床症状,并与术前进行比较.结果 16例患者中14例行左心房肺静脉前庭+左心房后壁+二尖瓣峡部消融后治愈,2例行左心房消融后仍可诱发阵发性心房颤动,在上腔静脉补充电隔离后治愈.与术前MRRI(5.6±1.6)s、NP>2 s( 152.5±67.3)次、MIHR( 36.4±8.6)次/min、MAHR(91.4±18.7)次/min和MEHR(57.2±10.4)次/min相比,术后1周及3个月的MRRI[ (2.4±1.3)s,(1.7±0.5)s]和NP>2s[(32.7±11.5)次,(2.2±1.3)次]明显降低(均为P <0.05),MIHR[( 45.3±11.3)次/min,(53.6±9.5)次/min]、MAHR[(103.2±14.5)次/min,( 122.5±15.8)次/min]和MEHR[(66.5±8.6)次/min,(75.3±12.7)次/min]明显增加(均为P<0.05),术后3个月与1周的各项指标比较差异有统计学意义(均为P<0.05).术前11例患者伴有头晕、黑矇等症状,术后所有患者均无这些症状.结论 快慢综合征心房颤动患者在心房颤动终止后而非发作前出现窦性停搏.心房颤动经射频消融治愈后,窦房结功能在术后3个月可完全恢复正常.%Objective To observe the heart rate alterations after radiofrequency ablation of paroxymal atrial fibrillation (AF) in patients with taehycardia-bradycardia syndrome and to investigate the impact of AF on sinus atrial node and functional restoration of sinus atrial node after elimination of AF. Methods From March 2007 to December 2010,16 paroxymal AF patients with documented longest pause equal to or more than 3 seconds after the termination

  13. 参仙升脉口服液联合阿托品治疗心动过缓性心律失常疗效观察%Effect observation of Senxianshengmai oral liquid oral liquid and atropine in treatment of bradycardia arrhythmias

    Institute of Scientific and Technical Information of China (English)



    Objective To observe the efficacy and value of Integrative treatment of arrhythmia.Methods Totally 58 patients were randomly divided into treatment groups of patients bradyarrhythmia and the control group, control group given western medicine treatment of 29 cases of oral atropine 0.3mg,3 times/day treatment.Besed on atropine the treatment group of 29 cases were added Senxianshengmai oral liquid 20mi orally,2 times/day.2 weeks.Results The treatment group obvious effective 7cases,effective in 17 cases,5 cases ineffective,the total effective rate was 92.6% ;Control group 3 cases were markedly,effective in 13 cases,ineffective in 13 cases,55% of the total effective rate.Difference between the two groups was significant ( P < 0.01 ); Surface ECG and 24 - hour ambulatory ECG,the treatment group and control group,the total effective rate was 90% and 41% ,the total number of 24 - hour heart rate were( 89420 ± 4800)time and (63250 ± 3700)times, the difference was significant ( P <0.01 ).Conclusions Integrative Medicine bradycardia effective than western medicine.Some patients can be free from pacemaker and is worthy of promotion.%目的 观察中西医结合疗法治疗缓慢性心律失常的疗效及应用价值.方法 随机将58例缓慢心律失常患者分为治疗组及对照组,对照绀29例给予西医治疗,口服阿托品0.3mg,3次/d治疗.治疗组29例在采用阿托品治疗基础上加用参仙升脉口服液,每次20ml口服,2次/d.疗程2周.结果 治疗组显效7例,有效17例,无效5例,总有效率92.6%;对照组显效3例.有效13例,无效13例,总有效55%.两组差别有统计学意义(P<0.01);体表心电图和24h动态心电图,治疗组和对照组总有效率分别为90%和41%,24h心率总数分别是(89 420±4 800)次和(63 250±3 700)次,两组差异有统计学意义(P<0.01).结论 中西医结合治疗缓慢性心律失常的疗效优于纯西药治疗.可使部分患者免于安装起搏器,值得临床推广.

  14. 24h Holter monitoring combined with atropine test in predicting the risk of sinus Bradycardia leading to sudden death%24h动态心电图结合阿托品试验预测窦性心动过缓患者猝死风险

    Institute of Scientific and Technical Information of China (English)



    目的 对窦性心动过缓(SN)患者作24 h动态心电图(Holter)检查,结尾时连接作阿托品激发窦房结试验,分析窦房结功能以进行猝死风险预测.方法 选择近4年来因各种原因未能安装心脏永久性起博器之SN患者43例,控制心功能在Ⅱ级以内,剔除房性、交界性和室性传导阻滞、Brugada综合征、J波综合征者.经24 h Holter检查延长1 h,静脉推注阿托品1.5~2.0 mg,记录1 h内最大心率变化,结合Holter最慢时间段心率判断SN患者猝死可能.结果 在43例SN患者中,Holter反应出最低时间的心率<45次/min有11例;40~60次/min有32例.在Holter结尾1 h阿托品激发试验中,最大心率<85次/min阳性,>85次/min为阴性,识别出猝死的高危、中危、低危人群.在此3组患者中总死亡人数为9例,占43例SN患者病死率20%,组间存在着不同的病死率.结论 窦性心动过缓患者最慢心率60次/min以下,Holter连接阿托品激发窦房结功能试验,1 h最大心率<85次/min为高危患者,4年内发生猝死可能性为83.3%,需安装永久性起搏器,以预防猝死发生.%Objective To analyze the function of sinus node (SN) and to predict sudden death by combined using of 24h dynamic electrocardiography (Holter) and atropine testing. Methods 43 patients with sinus bradycardia and without implantation of permanent pacemaker were selected for study. The cardiac function of all patients were ≤NYHA Ⅱ, excluding supraventricular and ventricular block, Brugada syndrome and J wave syndrome cases. The 24h Holter examination was taken with extension of one more hour. 1.5-2.0 mg of atropine were intravenously injected. The maximum heart rate within 1 hour was recorded. Combining with the slowest heart rate in Holter examination to forecast the sudden death possibility of SN patients. Results According to the results of Holter testing, there were 11 patientsˊ heart rate <45 bpm, 32 patientsˊ heart rate between 40 and 60 bpm

  15. Zebrafish M2 muscarinic acetylcholine receptor: cloning, pharmacological characterization, expression patterns and roles in embryonic bradycardia


    Hsieh, Dennis Jine-Yuan; Liao, Ching-Fong


    A zebrafish M2 muscarinic acetylcholine receptor (mAChR) gene was cloned. It encodes 495 amino acids in a single exon. The derived amino acid sequence is 73.5% identical to its human homologue.Competitive binding studies of the zebrafish M2 receptor and [3H]-NMS gave negative log dissociation constants (pKi) for each antagonist as follows: atropine (9.16)>himbacine (8.05)⩾4-DAMP (7.83)>AF-DX 116 (7.26)⩾pirenzepine (7.18)⩾tropicamide (6.97)⩾methoctramine (6.82)⩾p-F-HHSiD (6.67)>carbachol (5.20...

  16. [Sensitization of bradycardia during final hypotension induced by serotonin in rats: effect of lidocaine]. (United States)

    Valle, L B; Oliveira-Filho, R M; Armonia, P L; Nassif, M; Saraceni, G


    It was studied the sensibilizing effect of lidocaine (8.5 mg/kg, i.v.) on the ECG (heart rate, P-R interval, QRS complex and Q-T interval) of both intact and bilaterally vagotomised rats, in the nadir of the final hypotension determined by serotonine (60 mug/kg, i.v.). The results showed (1) a certain degree of selectivity of the vagi, and (2) the effects of serotonine either isolated or associated to lidocaine on P-R interval and heart rate were reinforced when intact animals were used. Although no significant alterations of Q-T were elicited by the drugs, lidocaine surprisingly enlarged the QRS complex in a more significant fashion for the intact than for the vagotomised animals.

  17. Pharmacological activation of rapid delayed rectifier potassium current suppresses bradycardia-induced triggered activity in the isolated guinea pig heart

    DEFF Research Database (Denmark)

    Hansen, Rie Schultz; Olesen, Søren-Peter; Grunnet, Morten


    arrhythmias. We present here data that support that NS3623 affects native I(Kr) and report the effects that activating this potassium current have in the intact guinea pig heart. In Langendorff-perfused hearts, the compound showed a concentration-dependent shortening of action potential duration, which...

  18. Non-expert listeners show decreased heart rate and increased blood pressure (fear bradycardia) in response to atonal music



    Previous studies suggested that listening to different types of music may modulate differently psychological mood and physiological responses associated with the induced emotions. In this study the effect of listening to instrumental classical vs. atonal contemporary music was examined in a group of 50 non-expert listeners. The subjects’ heart rate and diastolic and systolic blood pressure values were measured while they listened to music of different style and emotional typologies. Pieces we...

  19. Severe bradycardia caused by omeprazole: 4 case reports%奥美拉唑致严重心动过缓4例

    Institute of Scientific and Technical Information of China (English)

    钟建玲; 陈仕珠; 谢波


    Four male patients (aged 20,40,22, and 28 years) with chronic superficial gastritis or duodenal ulcer or gastric ulcer received omeprazole 20 mg twice daily. Three of them were given oral omeprazole alone. One of them received combined treatment with omeprazole, azithromycin, and colloidal bismmth pectin. Two days later, they developed dizziness, fatigue, chest distress, and short of breath. Their heart rate decreased to 44 beats/min, 46 beats /min, 46 beats /min, and 44 beats /min, respectively. After discontinuation of omeprazole and administration of IM atropine 0.5 mg 3 times a day, four patients' heart rate returned to baseline.%4例男性患者(年龄分别为20、40、22和28岁)分别因慢性浅表性胃炎、十二指肠球部溃疡或胃溃疡服用奥美拉唑20 mg,2次/d,其中3例单独口服奥美拉唑,1例合并应用奥美拉唑、阿奇霉素和胶体果胶铋.2d后均出现头晕、乏力、胸闷、气短等症状,心率分别下降为44、46、46和44 次/min.停用奥美拉唑并肌内注射阿托品0.5 mg,3次/d后,4例患者心率均恢复至用药前水平.

  20. Sinus Bradycardia and Multiple Episodes of Sinus Arrest With Lasting Period of More Than 14 Seconds Following Administration of Metoprolol: A Case Report

    Institute of Scientific and Technical Information of China (English)

    Gang Wang


    An aged male patient with coronary heart disease which had been treated with coronary artery bypass grafts (CABG) and administration of metoprolol,presented paroxysmal vertigo in the previous three weeks.The 24 hours synchronic 12-lead dynamic electrocardiography (DCG) revealed many episodes of sinus arrest which mostly were followed by A-V junctional or ventricular escape rhythm,the longest sinus pause lasting more than 14.5 seconds with no symptom.After withdrawal of metoprolol,the DCG revealed much less episodes of sinus arrest than on-admission,but still some A-V junctional and ventricular escape beats.Sick sinus syndromes was then diagnosed,and a synchronous dual-chamber pacemaker (DDDR) was implanted two weeks after admission.

  1. Inhibition of bradycardia pacing caused by far-field atrial sensing in a third-generation cardioverter defibrillator with an automatic gain feature. (United States)

    Curwin, J H; Roelke, M; Ruskin, J N


    The diagnostic accuracy of implantable cardioverter defibrillators may be improved by automatically adjusting gain algorithms, which in general reduce the likelihood of oversensing while maintaining the ability to detect the low amplitude signals associated with ventricular fibrillation. We present a patient with a third-generation device who developed prolonged ventricular asystole arising as a complication of the automatic gain feature. During asystole the device automatically increased sensitivity in order to prevent undersensing of ventricular fibrillation, which in this case resulted in far-field sensing of atrial activity and inhibition of ventricular pacing.

  2. The gain of the baroreflex bradycardia is reduced by microinjection of NMDA receptor antagonists into the nucleus tractus solitarii of awake rats. (United States)

    Frigero, M; Bonagamba, L G; Machado, B H


    The baroreflex activation with phenylephrine infusion produces a bradycardic response. In the present study, the role of NMDA receptors in the nucleus tractus solitarii (NTS) in the processing of the parasympathetic component of the baroreflex was evaluated using acid phosphonivaleric (AP-5), a selective NMDA receptor antagonist. Baroreflex activation was performed before and after bilateral microinjection of AP-5 into the intermediate commissural NTS (0.5 mm lateral to the midline). Microinjection of the vehicle (saline, 0.9%) or a dose of 2 nmol/50 nl of AP-5 into the NTS produced no effect on the gain of the baroreflex while a dose of 10 nmol/50 nl of AP-5 produced a significant reduction in the gain of the baroreflex 2 min after microinjection [-1.43+/-0.22 vs. -0. 43+/-0.03 bpm/mmHg, (n=6)], with a return to control levels 10 min after the microinjections. The dose of 10 nmol/50 nl was selective for NMDA receptors considering that the cardiovascular responses to microinjection of AMPA (0.05 pmol/50 nl), a non-NMDA receptor agonist, were not affected by this dose of AP-5 and the responses to microinjection of NMDA (2 nmol/50 nl) were blocked. The data show that the bradycardic response to baroreflex activation was blocked by AP-5 microinjected into the NTS, indicating that the neurotransmission of the parasympathetic component of the baroreflex is mediated by NMDA receptors in the NTS.

  3. Exercise Training and Grape Seed Extract Co-Administration Improves Lipid Profile, Weight Loss, Bradycardia, and Hypotension of STZ-Induced Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Mohammad Badavi


    Full Text Available Background:: Exercise Training (ET and Grape Seed Extract (GSE as an antioxidant have many positive effects on controlling diabetes mellitus and its complications. Objectives:: This study aimed to determine the effects of GSE alone or combined with ET on body weight, plasma lipid profile, blood pressure, and heart rate in STZ-induced diabetic rats. Methods:: In this study, male Wistar rats were randomly assigned to five groups: sedentary control, sedentary diabetic, trained diabetic, GSE treated sedentary diabetic, and GSE treated trained diabetic. ET was conducted on the treadmill daily for 8 weeks. One way ANOVA followed by LSD test was used for statistical analysis. Results:: Reduction of body weight, high density lipoproteins, heart rate, and systolic blood pressure and increment of total cholesterol, triglyceride, low density lipoprotein, and very low density lipoproteins were observed after STZ injection. Co-administration of GSE and ET had more positive effects on lipid profile compared to each method alone. In addition, GSE and ET modified heart rate partially, while their combination was more effective in improvement of heart rat in conscious rats. On the other hand, administration of ET or GSE alone did not affect systolic blood pressure and body weight, while their combination restored systolic blood pressure completely and improved body weight partially. Conclusions:: The study findings indicated that ET combined with GSE had more beneficial effects compared to each one alone on the complications of STZ induced diabetes. This may constitute a convenient and inexpensive therapeutic approach to diabetic complications.

  4. Abolition of reflex bradycardia by cardiac vagotomy has no effect on the regulation of oxygen uptake by Atlantic cod in progressive hypoxia

    DEFF Research Database (Denmark)

    McKenzie, David; Skov, Peter Vilhelm; Taylor, E.W.T.


    nerve X Cardiac denervation had no effect on oxygen uptake rate (M-O2), gill ventilation rate (f(G)) or opercular pressure amplitude (P-OP) under normoxic conditions, but caused a significant increase in heart rate (f(H)), to 50 +/- 1 beats min(-1) by comparison to 40 +/- 2 beats min(-1) in sham...

  5. Profound Autonomic Instability Complicated by Multiple Episodes of Cardiac Asystole and Refractory Bradycardia in a Patient with Anti-NMDA Encephalitis

    Directory of Open Access Journals (Sweden)

    Stephanie R. Mehr


    Full Text Available Anti-N-methyl-D-aspartate receptor encephalitis (anti-NMDARE is autoimmune encephalitis primarily affecting young adults and children. First described about a decade ago, it frequently manifests as a syndrome that includes progressive behavioral changes, psychosis, central hypoventilation, seizures, and autonomic instability. Although cardiac arrhythmias often accompany anti-NMDARE, the need for long-term electrophysiological support is rare. We describe the case of NMDARE whose ICU course was complicated by progressively worsening episodes of tachyarrhythmia-bradyarrhythmia and episodes of asystole from which she was successfully resuscitated. Her life-threatening episodes of autonomic instability were successfully controlled only after the placement of a permanent pacemaker during her ICU stay. She made a clinical recovery and was discharged to a skilled nursing facility after a protracted hospital course.

  6. The therapeutic effect of amiodarone on the elderly with sinus bradycardia and premature ventricular complexes%胺碘酮对老年心动过缓伴室性早搏临床疗效的观察

    Institute of Scientific and Technical Information of China (English)

    邵迴龙; 张红明; 高燕; 卫亚



  7. Peripheral 5-HT 1A and 5-HT 7 Serotonergic Receptors Modulate Parasympathetic Neurotransmission in Long-Term Diabetic Rats


    Beatriz Restrepo; María Luisa Martín; Luis San Román; Asunción Morán


    We analyzed the modulation of serotonin on the bradycardia induced in vivo by vagal electrical stimulation in alloxan-induced long-term diabetic rats. Bolus intravenous administration of serotonin had a dual effect on the bradycardia induced either by vagal stimulation or exogenous Ach, increasing it at low doses and decreasing it at high doses of 5-hydroxytryptamine (5-HT), effect reproduced by 5-carboxamidotryptamine maleate (5-CT), a 5-HT1/7 agonist. The enhancement of the bradycardia at l...

  8. Brain tumour as a rare cause of cardiac syncope.

    NARCIS (Netherlands)

    Sluijs, B.M. van der; Renier, W.O.; Kappelle, A.C.


    We report on a patient with a bradycardia followed by an asystole as expression of a complex partial seizure arising from a cerebral neoplasm in the medial part of the left temporal lobe. Previously published papers have shown that cardiac asystole and bradycardia as manifestation of epilepsy origin

  9. About Arrhythmia (United States)

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More About Arrhythmia Updated:Oct 26,2016 The term "arrhythmia" refers ... damaged. View an animation of arrhythmia . Types of Arrhythmias Atrial Fibrillation = upper heart chambers contract irregularly Bradycardia = ...

  10. Arrhythmia (United States)

    An arrhythmia is a problem with the rate or rhythm of your heartbeat. It means that your heart beats ... is called bradycardia. The most common type of arrhythmia is atrial fibrillation, which causes an irregular and ...

  11. Dexmedetomidine versus haloperidol for prevention of delir

    Directory of Open Access Journals (Sweden)

    Essam F. Abdelgalel


    Conclusion: Dexmedetomidine is more effective than haloperidol for prevention of delirium during NIV with lower incidence of endotracheal intubation and shorter ICU and hospital stay. Bradycardia is more frequent with dexmedetomidine use.

  12. Slow Heartbeat (United States)

    ... per minute. The heartbeat is controlled by an electrical system that signals the heart muscle to contract, or “squeeze,” pumping blood to the rest of the body. Bradycardia happens when the system slows or blocks ...

  13. Overlevelse efter massiv verapamiloverdosis hos en 48-årig kvinde

    DEFF Research Database (Denmark)

    Johansen, Karina K; Belhage, Bo


    , was hypotensive, and ECG showed bradycardia with nodal rhythm. The patient was treated with activated charcoal, colloids, crystalloids, norepinephrine, isoprenalin and epinephrine infusion, high dose glucose-insulin infusion and calcium. The patient was discharged for rehabilitation after two weeks...

  14. Transient Presyncope Secondary to Posterior Descending Artery Occlusion

    Directory of Open Access Journals (Sweden)

    Andrew D. Moffat


    Full Text Available We describe the case of a 64-year-old male initially presenting with presyncope and bradycardia, without any anginal symptoms or objective evidence of myocardial ischemia. A stress test induced no physical symptoms but revealed a left bundle branch block with multiple preventricular contractions on electrocardiogram. Subsequent catheterization revealed severe obstructive disease throughout the coronary arteries. He was treated percutaneously on two separate heart catheterizations. The presyncope and bradycardia resolved after reperfusion of the posterior descending artery.

  15. Bradycardiac angina: haemodynamic aspects and treatment. (United States)

    Fowler, P B; Ikram, H; Maini, R N; Makey, A R; Kirkham, J S


    A patient with a sinus bradycardia and angina is described who was unable to increase his heart rate on vigorous exercise by more than a few beats. His severe angina was attributed to the bradycardia. Atrial pacing of his heart abolished his angina and increased his exercise tolerance. Circulatory changes at rest, on exertion, and with atrial pacing are described. The cause of angina in this patient is discussed.

  16. Autonomic and electrocardiographic changes in cardioinhibitory syncope

    DEFF Research Database (Denmark)

    Mehlsen, Jesper; Kaijer, Michelle Nymann; Mehlsen, Anne-Birgitte


    Cardioinhibitory syncope (CS) is a neurally mediated response causing bradycardia or asystole. This study reports on changes in blood pressure, heart rate variability (HRV), and ECG patterns before and after syncope with asystole.......Cardioinhibitory syncope (CS) is a neurally mediated response causing bradycardia or asystole. This study reports on changes in blood pressure, heart rate variability (HRV), and ECG patterns before and after syncope with asystole....

  17. Role of ionotropic GABA, glutamate and glycine receptors in the tonic and reflex control of cardiac vagal outflow in the rat

    Directory of Open Access Journals (Sweden)

    Goodchild Ann K


    Full Text Available Abstract Background Cardiac vagal preganglionic neurons (CVPN are responsible for the tonic, reflex and respiratory modulation of heart rate (HR. Although CVPN receive GABAergic and glutamatergic inputs, likely involved in respiratory and reflex modulation of HR respectively, little else is known regarding the functions controlled by ionotropic inputs. Activation of g-protein coupled receptors (GPCR alters these inputs, but the functional consequence is largely unknown. The present study aimed to delineate how ionotropic GABAergic, glycinergic and glutamatergic inputs contribute to the tonic and reflex control of HR and in particular determine which receptor subtypes were involved. Furthermore, we wished to establish how activation of the 5-HT1A GPCR affects tonic and reflex control of HR and what ionotropic interactions this might involve. Results Microinjection of the GABAA antagonist picrotoxin into CVPN decreased HR but did not affect baroreflex bradycardia. The glycine antagonist strychnine did not alter HR or baroreflex bradycardia. Combined microinjection of the NMDA antagonist, MK801, and AMPA antagonist, CNQX, into CVPN evoked a small bradycardia and abolished baroreflex bradycardia. MK801 attenuated whereas CNQX abolished baroreceptor bradycardia. Control intravenous injections of the 5-HT1A agonist 8-OH-DPAT evoked a small bradycardia and potentiated baroreflex bradycardia. These effects were still observed following microinjection of picrotoxin but not strychnine into CVPN. Conclusions We conclude that activation of GABAA receptors set the level of HR whereas AMPA to a greater extent than NMDA receptors elicit baroreflex changes in HR. Furthermore, activation of 5-HT1A receptors evokes bradycardia and enhances baroreflex changes in HR due to interactions with glycinergic neurons involving strychnine receptors. This study provides reference for future studies investigating how diseases alter neurochemical inputs to CVPN.

  18. Cardiovascular effects of (-)-11-OH-delta 8-tetrahydrocannabinol-dimethylheptyl in rats. (United States)

    Vidrio, H; Sánchez-Salvatori, M A; Medina, M


    The effects of the stereochemically pure psychoactive cannabinoid (-)-11-OH-delta 8-tetrahydrocannabinol-dimethylheptyl (HU-210) on blood pressure (BP) and heart rate (HR) were determined in rats. In pentobarbital-anesthetized animals, the compound produced dose-related, long-lasting hypotension and bradycardia at doses between 10 and 1,000 micrograms/kg. BP began to decrease immediately after drug administration, and in no case was an initial pressor response observed. Previous vagotomy (VX) or pretreatment with 6-hydroxydopamine (6-OHDA) did not affect hypotension. Bradycardia was inhibited by VX, but only 60 min after administration of HU-210; it was enhanced by 6-OHDA. The cannabinoid blocked reflex bradycardia induced by phenylephrine (PE). HU-210 also decreased BP and HR in conscious rats. Hypotension lasted 2 h, whereas bradycardia was still present 8 h after drug administration. HU-210 thus shares with delta 9-tetrahydrocannabinol (THC) the ability to decrease BP and HR, but is 5-10 times more potent than the natural compound. Its lack of an initial pressor effect, such as that described for THC, could be related to its specificity for the type-1 cannabinoid (CB1) receptor. Hypotension and bradycardia after HU-210 administration are not due to sympathetic withdrawal. Enhanced parasympathetic tone is involved in bradycardia only at a late stage of the response.

  19. Evaluation of the diving reflex in response to nonterminal submersion of White Pekin ducks in water-based foam. (United States)

    Caputo, M P; Alphin, R L; Pritchett, E; Hougentogler, D P; Johnson, A L; Benson, E R; Patil, C


    The mass depopulation of production birds remains an effective means of controlling fast-moving, highly infectious diseases such as avian influenza and virulent Newcastle disease. Water-based fire-fighting foam is a conditionally approved method of depopulating floor-reared gallinaceous poultry such as chickens and turkeys; however, ducks have physiological mechanisms that may make them more resistant to this method of depopulation. The following experiment was designed to assess the physiological responses of White Pekin ducks to nonterminal submersion in water-based foam compared with water. The hypothesis of this experiment was that submersion of ducks in water or water-based foam would trigger the diving reflex and lead to bradycardia. All treatments led to pronounced bradycardia. Heart rate was not significantly different between treatments during the final 30 s of the 60-s treatment period. Heart rate dropped significantly faster for the water dip and foam dip treatments and rose significantly faster than the foam pour treatment after the termination of the 60-s treatment period. Duration of bradycardia approached significance for the foam pour treatment, leading to a longer duration of bradycardia compared with the water pour, water dip, and foam dip treatments. The results of this experiment demonstrated that apnea and bradycardia as a result of the diving reflex can occur as a result of submersion in foam, which may have an impact on the time it takes White Pekin ducks to reach unconsciousness and death during water-based foam depopulation.

  20. Endomorphins decrease heart rate and blood pressure possibly by activating vagal afferents in anesthetized rats. (United States)

    Kwok, E H; Dun, N J


    Endomorphin 1 (10, 30, 100 nmol/kg) administered intravenously (i.v. ) to urethane-anesthetized rats consistently and dose-dependently lowered heart rate (HR) and mean arterial pressure (MAP); the decrease in blood pressure recovered faster as compared to the HR. The effects of endomorphin 2 were qualitatively similar. Naloxone (2 mg/kg, i.v.) completely antagonized the bradycardia and hypotension caused by endomorphin 1. Pretreatment of the rats with atropine methylnitrate, atropine sulfate (2 mg/kg, i.v.) or bilateral vagotomy nearly abolished the bradycardia and attenuated the hypotensive effect of endomorphin 1. Our studies suggest that the bradycardia effect following systemic administration of the new opioid peptide may be explained by activation of vagal afferents and the hypotensive effect may be secondary to a reduction of cardiac output and/or a direct vasodilation.

  1. [Acute traumatic spinal cord injury and cardiovascular complications due to neurogenic shock: a possible threat for functional recovery]. (United States)

    van de Meent, H; Vos, P E; Schreuder, H W; van der Hoeven, J G


    Three men aged 18, 18 and 24 years, developed hypotension and bradycardia following an acute traumatic cervical or thoracic spinal cord injury. After treatment in intensive care and 1-12 months of rehabilitation they still suffered from considerable neurological disorders. Hypotension and bradycardia are common phenomena following acute traumatic cervical and thoracic spinal cord injury. Awareness of cardiovascular complications as a possible threat for functional recovery and adequate insight in the neurological cause of hypotension and bradycardia are important issues in the acute treatment of patients with spinal cord injury. It seems sensible to admit these patients to a medium-care or intensive-care department where they can be monitored and treated by a specialised team in accordance with an adequate protocol.

  2. Ruta Graveolens intoxication. (United States)

    Seak, Chen-June; Lin, Chih-Chuan


    We describe a case of unintentional poisoning from Ruta Graveolens, a medicinal herb that is used for heart protection in Taiwan. A 78-year-old woman developed bradycardia, acute renal failure with hyperkalemia, and coagulopathy after three days of consuming a decoction made from Ruta Graveolens for the treatment of palpitations and heart protection. She was treated with hemodialysis in the emergency department for hyperkalemia. Her bradycardia and hypotension improved gradually three days later. Ruta use might cause multi-organ toxicity. We believe this case report helps in the recognition of the systemic toxicity of Ruta Graveolens.

  3. A reminder about the trigeminocardiac reflex in surgeries at the posterior third of the falx cerebri

    Directory of Open Access Journals (Sweden)

    Koji Takano


    Full Text Available The trigeminocardiac reflex (TCR is defined as a reproducible hypotension and bradycardia coinciding with the manipulation around the trigeminal nerve. Here, we report a case of sudden bradycardia with falcine manipulation. As the falx cerebri is innervated by the nervus tentorii, which is a recurrent branch of the ophthalmic nerve, the observed asystole is highly possible to be caused by TCR. Anesthesiologists and neurosurgeons should be fully aware of the anatomical innervation of the falx cerebri and that the posterior third of the falx cerebri is one of the highest risk structures for TCR induction for safe operation around this region.

  4. Nicorandil-Induced Hyperkalemia in a Uremic Patient

    Directory of Open Access Journals (Sweden)

    Hung-Hao Lee


    Full Text Available Nicorandil is an antianginal agent with nitrate-like and ATP-sensitive potassium channel activator properties. After activation of potassium channels, potassium ions are expelled out of the cells, which lead to membrane hyperpolarization, closure of voltage-gated calcium channels, and finally vasodilation. We present a uremic case suffering from repeated junctional bradycardia, especially before hemodialysis. After detailed evaluation, nicorandil was suspected to be the cause of hyperkalemia which induced bradycardia. This case reminds us that physicians should be aware of this potential complication in patients receiving ATP-sensitive potassium channel activator.

  5. Perioperative Beta Blockade - A Case Report

    Directory of Open Access Journals (Sweden)

    Sunitha K. Zachariah


    Full Text Available Continuation of antihypertensives preoperatively and their influence on intraoperative hemodynamics is a big concern among anesthesiologists. The Peri Operative Ischaemia Study Evaluation (POISE trial showed a significant reduction of myocardial infarction, need for coronary revascularization and the incidence of atrial fibrillation with metoprolol started 2-4 hours prior to surgery but a significant increase in total mortality and clinically significant hypotension and bradycardia. This is a case report of intraoperative severe bradycardia in a young patient on recently started beta blocker.

  6. Hyperpyrexia associated with congenital Long QT Syndrome

    Directory of Open Access Journals (Sweden)

    Nuriye Tarakci


    Full Text Available Congenital long QT syndrome (CLQTS is a genetic disorder presented with prolonged QT interval. In these patients, risk of sudden cardiac death due to ventricular tachyarrhythmias is high. Bradycardia may exhibit as a result of intrauterine fetal atrioventricular block, sinus bradycardia, tachycardia in these patient. Prolonged QT interval and multisystem involvement such as sensorineural hearing loss, muscle paralysis, immune deficiency, syndactyly have been reported in these patient . We have detected hyperpyrexia without clinical immunodeficiency and infection in our patient. To our knowledge, our patient is the first case in the literature . [Cukurova Med J 2014; 39(4.000: 909-903

  7. Orthognathic surgery with or without induced hypotension. (United States)

    Carlos, E; Monnazzi, M S; Castiglia, Y M M; Gabrielli, M F R; Passeri, L A; Guimarães, N C


    This study involved a retrospective evaluation of patients subjected to surgery for dentofacial deformities treated without induced controlled hypotension (group I, n=50) and a prospective evaluation of patients who were subjected to surgery under hypotensive general anaesthesia (group II, n=50). No statistical differences were found between the study groups with regard to the duration of surgery. However, there were statistically significant differences in the need for blood transfusion and the occurrence of bradycardia during the maxillary down-fracture. Hypotensive anaesthesia decreased the need for a blood transfusion and the occurrence of bradycardia, and is therefore considered highly beneficial for patients undergoing orthognathic surgery.

  8. An Experimental Model of Vasovagal Syncope Induces Cerebral Hypoperfusion and Fainting-Like Behavior in Awake Rats (United States)

    McBride, Devin W.; Reis, Cesar; Frank, Ethan; Klebe, Damon W.; Zhang, John H.; Applegate, Richard


    Vasovagal syncope, a contributing factor to elderly falls, is the transient loss of consciousness caused by decreased cerebral perfusion. Vasovagal syncope is characterized by hypotension, bradycardia, and reduced cerebral blood flow, resulting in fatigue, altered coordination, and fainting. The purpose of this study is to develop an animal model which is similar to human vasovagal syncope and establish an awake animal model of vasovagal syncope. Male Sprague-Dawley rats were subjected to sinusoidal galvanic vestibular stimulation (sGVS). Blood pressure, heart rate, and cerebral blood flow were monitored before, during, and post-stimulation. sGVS resulted in hypotension, bradycardia, and decreased cerebral blood flow. One cohort of animals was subjected to sGVS while freely moving. sGVS in awake animals produced vasovagal syncope-like symptoms, including fatigue and uncoordinated movements; two animals experienced spontaneous falling. Another cohort of animals was preconditioned with isoflurane for several days before being subjected to sGVS. Isoflurane preconditioning before sGVS did not prevent sGVS-induced hypotension or bradycardia, yet isoflurane preconditioning attenuated sGVS-induced cerebral blood flow reduction. The sGVS rat model mimics elements of human vasovagal syncope pathophysiology (hypotension, bradycardia, and decreased cerebral perfusion), including behavioral symptoms such as fatigue and altered balance. This study indicates that the sGVS rat model is similar to human vasovagal syncope and that therapies directed at preventing cerebral hypoperfusion may decrease syncopal episodes and reduce injuries from syncopal falls. PMID:27658057

  9. Molecular Cloning and Pharmacology of Porcine 5-Hydroxytryptamine Receptors Relevant to the Study of Antimigraine Drugs

    NARCIS (Netherlands)

    P.L. Bhalla (Pankaj)


    textabstractAt the beginning of last century, Brodie (1900) described in an extensive study that injection of blood serum causes vasoconstriction and a vagally-mediated reflex resulting in a reversible bradycardia, hypotension and arrest of the respiration, while injection of blood plasma was devoid

  10. Brief Report: Electroconvulsive Therapy for Malignant Catatonia in an Autistic Adolescent (United States)

    Wachtel, Lee Elizabeth; Griffin, Margaret Merrie; Dhossche, Dirk Marcel; Reti, Irving Michael


    A 14-year-old male with autism and mild mental retardation developed malignant catatonia characterized by classic symptoms of catatonia, bradycardia and hypothermia. Bilateral electroconvulsive therapy and lorazepam were required for resolution. The case expands the occurrence of catatonia in autism into its malignant variant.

  11. Neostigmine for treatment of acute colonic pseudo-obstruction

    Directory of Open Access Journals (Sweden)

    Suri S


    Full Text Available Acute colonic pseudo-obstruction is managed with bolus neostigmine as shown in a recent prospective, double blind, placebo-controlled study. Parasympathetic stimulation with neostigmine leads to abdominal pain, salivation, and symptomatic bradycardia. We submit a more effective method may involve use of neostigmine infusion to reduce complications and improve efficacy.

  12. Low atrial septum pacing in pacemaker patients

    NARCIS (Netherlands)

    Voogt, Willem Gijsbert de


    In patients with an indication for anti bradycardia pacing, atrial fibrillation (AF) is a common arrhythmia (30-50%) even in the absence of atrial tachy arrhythmias before pacemaker implantation. Pace prevention and pace intervention for atrial tachy arrhythmias could be an interesting adjuvant trea

  13. Prophylactic administration of atropine attenuates the negative haemodynamic effects of propofol/remifentanil induction of anaesthesia.

    NARCIS (Netherlands)

    Poterman, Marieke; Scheeren, Thomas; van der Velde, M.I.; Struys, Michel; Kalmar, A.F.


    Background and Goal of Study:   Induction of anaesthesia with propofol and remifentanil often induces unwanted bradycardia and hypotension. This raises the concern for preserving haemodynamic stability and adequate tissue oxygenation. We previously demonstrated that atropine significantly improves h

  14. Mental imagery affects subsequent automatic defense responses

    Directory of Open Access Journals (Sweden)

    Muriel A Hagenaars


    Full Text Available Automatic defense responses promote survival and appropriate action under threat. They have also been associated with the development of threat-related psychiatric syndromes. Targeting such automatic responses during threat may be useful in populations with frequent threat exposure. Here, two experiments explored whether mental imagery as a pre-trauma manipulation could influence fear bradycardia (a core characteristic of freezing during subsequent analogue trauma (affective picture viewing. Image-based interventions have proven successful in the treatment of threat-related disorders, and are easily applicable. In Experiment 1 43 healthy participants were randomly assigned to an imagery script condition. Participants executed a passive viewing task with blocks of neutral, pleasant and unpleasant pictures after listening to an auditory script that was either related (with a positive or a negative outcome or unrelated to the unpleasant pictures from the passive viewing task. Heart rate was assessed during script listening and during passive viewing. Imagining negative related scripts resulted in greater bradycardia (neutral-unpleasant contrast than imagining positive scripts, especially unrelated. This effect was replicated in Experiment 2 (N = 51, again in the neutral-unpleasant contrast. An extra no-script condition showed that bradycardia was not induced by the negative related script, but rather that a positive script attenuated bradycardia. These preliminary results might indicate reduced vigilance after unrelated positive events. Future research should replicate these findings using a larger sample. Either way, the findings show that highly automatic defense behavior can be influenced by relatively simple mental imagery manipulations.

  15. Clonidine overdose. (United States)

    Marruecos, L; Roglan, A; Frati, M E; Artigas, A


    A case of acute intoxication in a 60-yr-old woman who ingested 20 mg of clonidine is presented. The patient showed CNS depression (bradycardia, hypotonia) with systemic hypertension and peripheral vasoconstriction. She was treated with atropine and sodium nitroprusside. There was no recurrence and the patient recovered in 8 days.

  16. Facing Freeze: Social Threat Induces Bodily Freeze in Humans

    NARCIS (Netherlands)

    Roelofs, K.; Hagenaars, M.A.; Stins, J.F.


    Freezing is a common defensive response in animals threatened by predators. It is characterized by reduced body motion and decreased heart rate (bradycardia). However, despite the relevance of animal defense models in human stress research, studies have not shown whether social threat cues elicit si

  17. Complete recovery after severe myxoedema coma complicated by status epilepticus

    DEFF Research Database (Denmark)

    Fjølner, Jesper; Opstrup, Ulla Kampmann; Søndergaard, Esben;


    We report a case of life-threatening myxoedema presenting with hypothermia, hypotension, bradycardia, pericardial effusion and deep coma. The condition was complicated by prolonged status epilepticus. The optimal treatment strategy has been debated over the years and the literature is briefly...

  18. Not Just a Drop in the Bucket-Inversion of Oxymetazoline Nasal Decongestant Container Increases Potential for Severe Pediatric Poisoning. (United States)

    Nordt, Sean Patrick; Vivero, Lisa E; Cantrell, F Lee


    Oxymetazoline is an over-the-counter nasal decongestant with potent alpha agonist properties. In overdoses as small as 1-2 mL, toxicity can be seen including bradycardia and respiratory depression. We demonstrated that inverting the container increased the volume delivered 20- to 30-fold compared with holding it upright in an in vitro model.

  19. Peripheral 5-HT 1A and 5-HT 7 Serotonergic Receptors Modulate Parasympathetic Neurotransmission in Long-Term Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Beatriz Restrepo


    Full Text Available We analyzed the modulation of serotonin on the bradycardia induced in vivo by vagal electrical stimulation in alloxan-induced long-term diabetic rats. Bolus intravenous administration of serotonin had a dual effect on the bradycardia induced either by vagal stimulation or exogenous Ach, increasing it at low doses and decreasing it at high doses of 5-hydroxytryptamine (5-HT, effect reproduced by 5-carboxamidotryptamine maleate (5-CT, a 5-HT1/7 agonist. The enhancement of the bradycardia at low doses of 5-CT was reproduced by 5-HT1A agonist 8-hydroxy-2-dipropylaminotetralin hydrobromide (8-OH-DPAT and abolished by WAY-100,635, 5-HT1A antagonist. Pretreatment with 5-HT1 antagonist methiothepin blocked the stimulatory and inhibitory effect of 5-CT, whereas pimozide, 5-HT7 antagonist, only abolished 5-CT inhibitory action. In conclusion, long-term diabetes elicits changes in the subtype of the 5-HT receptor involved in modulation of vagally induced bradycardia. Activation of the 5-HT1A receptors induces enhancement, whereas attenuation is due to 5-HT7 receptor activation. This 5-HT dual effect occurs at pre- and postjunctional levels.

  20. 78 FR 17123 - Amitraz; Pesticide Tolerances (United States)


    ... establishing tolerances for residues of the insecticide, amitraz, (N'- -N-[[(2,4- dimethylphenyl)imino]methyl... metabolism study, neurotoxic effects such as dry mouth, drowsiness, decreased temperature, and bradycardia.... The human metabolism study showed neurotoxic effects shortly after dosing, which disappeared within...

  1. Analgetic treatment in acute myocardial infarction. A controlled clinical comparison of morphine, nicomorphine and pethidine

    DEFF Research Database (Denmark)

    Nielsen, J R; Pedersen, K E; Dahlstrøm, C G


    reactions were few (allergy 3 cases, respiratory insufficiency 4, severe bradycardia 4), whereas nausea was recorded in 20-30%, vomiting in 5-15% and dizziness in 10-30% of the patients, with no difference between the three drugs. Significant blood pressure drop (greater than 30 mmHg) was seen in 3...

  2. Repeated administration of adenosine increases its cardiovascular effects in rats. (United States)

    Vidrio, H; García-Márquez, F; Magos, G A


    Hypotensive and negative chronotropic responses to adenosine in anesthetized rats increased after previous administration of the nucleoside. Bradycardia after adenosine in the isolated perfused rat heart was also potentiated after repeated administration at short intervals. This self-potentiation could be due to extracellular accumulation of adenosine and persistent stimulation of receptors caused by saturation or inhibition of cellular uptake of adenosine.

  3. Peripheral 5-HT1A and 5-HT7 Serotonergic Receptors Modulate Parasympathetic Neurotransmission in Long-Term Diabetic Rats (United States)

    Restrepo, Beatriz; Martín, María Luisa; San Román, Luis; Morán, Asunción


    We analyzed the modulation of serotonin on the bradycardia induced in vivo by vagal electrical stimulation in alloxan-induced long-term diabetic rats. Bolus intravenous administration of serotonin had a dual effect on the bradycardia induced either by vagal stimulation or exogenous Ach, increasing it at low doses and decreasing it at high doses of 5-hydroxytryptamine (5-HT), effect reproduced by 5-carboxamidotryptamine maleate (5-CT), a 5-HT1/7 agonist. The enhancement of the bradycardia at low doses of 5-CT was reproduced by 5-HT1A agonist 8-hydroxy-2-dipropylaminotetralin hydrobromide (8-OH-DPAT) and abolished by WAY-100,635, 5-HT1A antagonist. Pretreatment with 5-HT1 antagonist methiothepin blocked the stimulatory and inhibitory effect of 5-CT, whereas pimozide, 5-HT7 antagonist, only abolished 5-CT inhibitory action. In conclusion, long-term diabetes elicits changes in the subtype of the 5-HT receptor involved in modulation of vagally induced bradycardia. Activation of the 5-HT1A receptors induces enhancement, whereas attenuation is due to 5-HT7 receptor activation. This 5-HT dual effect occurs at pre- and postjunctional levels. PMID:21403818

  4. Response to suxamethonium during propofol-fentanyl-N2O/O2 anaesthesia in a patient with active myasthenia gravis receiving long-term anticholinesterase therapy. (United States)

    Vanlinthout, L E; Robertson, E N; Booij, L H


    We describe the effect of repeated suxamethonium doses during propofol-fentanyl-N2O/O2 anaesthesia in a 29-year-old woman with active myasthenia gravis receiving chronic pyridostigmine therapy. Despite adequate pre-operative pseudocholinesterase activity, suxamethonium resistance occurred. Neither bradycardia nor residual neuromuscular block were seen after repeated doses of suxamethonium.

  5. Severe hypotension related to high negative pressure suction drainage on a thoracic epidural drain during multilevel spinal fixation. (United States)

    Brahmbhatt, Anjalee; Hall, Nicholas D P; Bradley, William Pierre Litherland


    Hypotension or bradycardia or both related to intracranial hypotension after craniotomy has been reported in the literature. However, such reports are uncommon with thoracic epidural drains. We describe a case in which application of high negative pressure suction to a thoracic epidural drain caused a sudden decrease in arterial blood pressure.

  6. Pharmacological management of hemodynamic complications following spinal cord injury. (United States)

    McMahon, Deanna; Tutt, Matthew; Cook, Aaron M


    Damage from spinal cord injury (SCI) may be complicated by concomitant hemodynamic alterations within hours to months of the initial insult. Neurogenic shock, symptomatic bradycardia, autonomic dysreflexia, and orthostatic hypotension are specific conditions occurring commonly with SCI. Early recognition and appropriate management of each disorder may minimize secondary injury to the cord, avert systemic complications, and help alleviate patient discomfort.

  7. [Acute traumatic spinal cord injury and cardiovascular complications due to neurogenic shock: a possible threat for functional recovery

    NARCIS (Netherlands)

    Meent, H. van de; Vos, P.E.; Schreuder, H.W.B.; Hoeven, J.G. van der


    Three men aged 18, 18 and 24 years, developed hypotension and bradycardia following an acute traumatic cervical or thoracic spinal cord injury. After treatment in intensive care and 1-12 months of rehabilitation they still suffered from considerable neurological disorders. Hypotension and bradycardi

  8. Propranolol in the treatment of assaultive patients with organic brain disease. (United States)

    Greendyke, R M; Schuster, D B; Wooton, J A


    Propranolol in doses up to 520 mg/day was administered to eight patients with organic brain disease characterized by violent and assaultive behavior refractory to conventional treatment. Improvement was demonstrated in the seven patients able to tolerate adequate drug dosages. Hypotension, bradycardia, and interactions with other medications constituted complications.

  9. A comparison of single-lead atrial pacing with dual-chamber pacing in sick sinus syndrome

    DEFF Research Database (Denmark)

    Nielsen, Jens Cosedis; Thomsen, Poul Erik B; Højberg, Søren


    In patients with sick sinus syndrome, bradycardia can be treated with a single-lead pacemaker or a dual-chamber pacemaker. Previous trials have revealed that pacing modes preserving atrio-ventricular synchrony are superior to single-lead ventricular pacing, but it remains unclear if there is any ...

  10. Signal transduction in cultered cardiomyocytes : alpha1-adrenergic and endothelin receptor mediated responses

    NARCIS (Netherlands)

    H.W. de Jonge (Jet)


    textabstractAlready in ancient times the Greek were aware of the heart in the human body and they gave it the name kardia, which is still in use in words as cardiac, myocardial, tachycardia and bradycardia. In those times the importance of the heart was appraised by Aristotle (384-322 B.C.), who tho

  11. Serotonin receptors as cardiovascular targets

    NARCIS (Netherlands)

    C.M. Villalón (Carlos); P.A.M. de Vries (Peter); P.R. Saxena (Pramod Ranjan)


    textabstractSerotonin exerts complex effects in the cardiovascular system, including hypotension or hypertension, vasodilatation or vasoconstriction, and/or bradycardia or tachycardia; the eventual response depends primarily on the nature of the 5-HT receptors involved. In the light of current 5-HT

  12. Varierende sygdomsbilleder hos mindre børn med Influenzavirus type A infektioner

    DEFF Research Database (Denmark)

    Olsen, P M; Hornsleth, A; Krasilnikoff, P A


    . Eight patients had febrile convulsions, a girl aged nine years had double vision and vertigo and a female infant aged two months had periodic apnoea and bradycardia. The reasons for hospitalization were febrile convulsions, abdominal pain, lower respiratory tract symptoms and high pyrexia....

  13. Sinus node dysfunction in non-medicational treatment of atrial fibrillation

    Directory of Open Access Journals (Sweden)

    Bockeria L. А.


    Full Text Available Sinus node dysfunction or sick sinus syndrome (SSS includes clinical conditions such as symptomatic sinus bradycardia, sinus pauses or arrest, sinus node exit block, atrial tachycardias and chronotropic incompetence. Even though SSS incidence increases in an exponential-like manner with age, it can occur at all ages, including in the newborn. The mean age of patients with the syndrome is 68 years, with both genders being affected in approximately equal proportion. This condition occurs in 1 of every 600 cardiac patients over 65. Degenerative fibrosis of the tissues of the node has been suggested to be a common cause of SSS. Although it is still disputed. SSS is frequently associated with atrial fibrillation and flutter, tachy-bradycardia syndrome. Tachy-bradycardia syndrome is defined as sinus bradycardia coupled with atrial flutter/fibrillation or reciprocal atrial tachycardia. This syndrome is common in young patients following a surgical treatment of a congenital heart disease. Patients with chronic or persistent atrial flutter/fibrillation show high rates of cardiovascular disorders and mortality while sinus bradycardia is thought as an independent risk factor of atrial flutter/fibrillation. There are certain restrictions to medical treatment: long-term administration of the same medication (sotalol, amiodarone for atrial flutter/fibrillation can cause symptomatic bradycardia while administration of other medication (a class 1 drug increases the likelihood of ventricular arrythmias or evident bradycardia that enhances the risk of sudden cardiac death. Following atrial fibrillation ablation patients saw a significant improvement in the sinus node function, or saw a better sinus node function disrupted due to remodelling that takes place during atrial fibrillation. The surgical methods applications proved most efficient in non-medicational treatment of atrial fibrillation. In the late 1980s American surgeon J. L. Cox developed a so-called Maze

  14. Closed versus partially ventilated endotracheal suction in extremely preterm neonates: physiologic consequences. (United States)

    Tan, A M; Gomez, J M; Mathews, J; Williams, M; Paratz, J; Rajadurai, V S


    This randomized cross over study aimed to compare the severity and incidences of desaturation and bradycardia between the partially ventilated endotracheal suction method (PVETS) and closed tracheal suction system (CTSS) in extremely preterm neonates. Fifteen intubated and ventilated extremely low birth weight preterm infants (mean birth weight 689g) randomly underwent both suction techniques within a 12-h period to obtain a paired reading group. The process was repeated 24-48h apart until three pairs of reading groups were collected. Changes in oxygen saturation measured with pulse oximetry and heart rate changes measured with electrocardiogram were recorded using Hewlett-Packard m240A monitor trending software. The mean of each parameter's variation from baseline was obtained using SPSS descriptive statistics and analyzed using SPSS repeated measures ANOVA. Fisher Exact Test was used to analyze the incidence of desaturation and bradycardia. The closed tracheal suction system reported a significantly smaller degree of oxygen saturation fall (Ppreterm population.

  15. Anaplastic lymphoma kinase-positive lung adenocarcinoma patient with development of sick sinus syndrome while on targeted treatment with crizotinib. (United States)

    Jiang, Hao; Li, Mei-Mei; Jin, Shu-Xian


    The anaplastic lymphoma kinase (ALK) positive non-small cell lung cancer (NSCLC) patients are younger and have never smoked, while pathologically are predominately adenocarcinomas. Crizotinib as an ALK inhibitor has been used in treating ALK positive NSCLC patients for several years and some adverse effects should be paid attention to. We now describe a case of ALK positive NSCLC patient with development of sick sinus syndrome (SSS) while on targeted treatment with crizotinib. A 46-year-old non-smoking woman with right hilar mass and underwent transesophageal endoscopic ultrasonography lymph node biopsy showed low differentiation adenocarcinoma, immunohistochemistry (IHC) of tumor samples revealed the ALK overexpression. The severe sinus bradycardia and RR interval prolongation were detected 3 months after crizotinib treatment, she underwent pacemaker implantation. Although the severe sinus bradycardia and RR interval prolongation were unusual adverse effects, physicians should be aware of these side effects when using crizotinib.

  16. Trigemino-cardiac reflex during orbital floor reconstruction: a case report and review. (United States)

    Vasudev, Sunil; Reddy, K Sudhakara


    Trigemino-cardiac reflex is occurrence of hypotension and bradycardia upon surgical manipulation of areas supplied by the trigeminal nerve, and has been reported during craniofacial maxillofacial and ocular surgeries. Communication between the anaesthetic and surgical team is essential, and cessation of the precipitating stimulus is the first and most important therapeutic step. We report a case of immediate, reproducible, and reflexive response of Bradycardia and dysrhythmia upon manipulation of orbital fracture during orbital floor reconstruction in a 65-year-old man. Upon recognition of the reproducible relationship between falcine stimulation and increased vagal tone, the patient was given atropine in an effort to block cholinergic hyperactivity. After atropine administration, no further dysrhythmias occurred and surgery was carried uneventfully.

  17. Inaccurate reporting of simulated critical anaesthetic incidents. (United States)

    Byrne, A J; Jones, J G


    Eleven anaesthetists completed a simulated anaesthetic which was deliberately complicated by a slow progressive bradycardia followed by an episode of severe bronchospasm. After the simulation, each anaesthetist was asked to complete an anaesthetic chart and a critical incident report. Considerable discrepancies were found between the anaesthetists' written accounts, a videotape of their performance and actual data from the simulator. During the simulations, all of the anaesthetists reacted appropriately and treated their "patient" successfully but their written accounts showed a tendency to record "typical" rather than actual events and to ignore events not consistent with their final diagnosis. Only four anaesthetists mentioned bradycardia in their written description and none accurately described the changes in arterial pressure during the episode of bronchospasm. The findings are in keeping with other studies which suggest that people record events as "schemata" rather than as collections of discrete facts. These results have significant implications for those involved in the teaching of anaesthesia and in the analysis of critical incidents.

  18. Cardiac arrhythmias associated with spinal cord injury

    DEFF Research Database (Denmark)

    Hector, Sven Magnus; Biering-Sørensen, Tor; Krassioukov, Andrei;


    CONTEXT/OBJECTIVES: To review the current literature to reveal the incidence of cardiac arrhythmias and its relation to spinal cord injury (SCI). METHODS: Data source: MEDLINE database, 304 hits, and 32 articles were found to be relevant. The relevant articles all met the inclusion criteria: (1......) contained original data (2) on cardiac arrhythmias (3) in humans with (4) traumatic SCI. RESULTS: In the acute phase of SCI (1-14 days after injury) more cranial as well as more severe injuries seemed to increase the incidence of bradycardia. Articles not covering the first 14 days after injury, thus...... as during procedures such as penile vibro-stimulation and tracheal suction. These episodes of bradycardia were seen more often in individuals with cervical injuries. Longitudinal studies with continuous electrocardiogram recordings are needed to uncover the true relation between cardiac arrhythmias and SCI....

  19. Cardiac arrhythmias the first month after acute traumatic spinal cord injury

    DEFF Research Database (Denmark)

    Bartholdy, Kim; Biering-Sørensen, Tor; Malmqvist, Lasse


    of this prospective observational study was to investigate the occurrence of cardiac arrhythmias and cardiac arrests in patients with acute traumatic SCI. METHODS: As early as possible after SCI 24-hour Holter monitoring was performed. Additional Holter recordings were performed 1, 2, 3, and 4 weeks after SCI....... Furthermore, 12-lead electrocardiograms (ECGs) were obtained shortly after SCI and at 4 weeks. RESULTS: Thirty patients were included. Bradycardia (heart rate (HR) ... both on 12-lead ECGs obtained shortly after SCI (P = 0.030) and at 4 weeks (P = 0.041). CONCLUSION: Many patients with cervical SCI experience arrhythmias such as bradycardia, sinus node arrest, supraventricular tachycardia, and more rarely cardiac arrest the first month after SCI. Apart from sinus...

  20. Characterization of T cell clones from chagasic patients: predominance of CD8 surface phenotype in clones from patients with pathology

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    Washington R. Cuna


    Full Text Available Human Chagas' disease, caused by the protozoan Trypanosoma cruzi, is associated with pathological processes whose mechanisms are not known. To address this question, T cell lines were developed from chronic chagasic patients peripheral blood mononuclear cells (PBMC and cloned. These T cell clones (TCC were analyzed phenotypically with monoclonal antibodies by the use of a fluorescence microscope. The surface phenotype of the TCC from the asymptomatic patient were predominantly CD4 positive (86%. On the contrary, the surface phenotype CD8 was predominant in the TCC from the patients suffering from cardiomegaly with right bundle branch block (83%, bradycardia with megacolon (75 % and bradycardia (75%. Future studies will be developed in order to identify the antigens eliciting these T cell subpopulations.

  1. Iatrogenic tension pneumothorax in children: two case reports

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    Mayordomo-Colunga Juan


    Full Text Available Abstract Introduction Two cases of iatrogenic tension pneumothorax in children are reported. Case presentations Case 1: A 2-year-old boy with suspected brain death after suffering multiple trauma suddenly developed intense cyanosis, extreme bradycardia and generalized subcutaneous emphysema during apnea testing. He received advanced cardiopulmonary resuscitation and urgent bilateral needle thoracostomy. Case 2: A diagnostic-therapeutic flexible bronchoscopy was conducted on a 17-month-old girl, under sedation-analgesia with midazolam and ketamine. She very suddenly developed bradycardia, generalized cyanosis and cervical, thoracic and abdominal subcutaneous emphysema. Urgent needle decompression of both hemithoraces was performed. Conclusion In techniques where gas is introduced into a child's airway, it is vital to ensure its way out to avoid iatrogenic tension pneumothorax. Moreover, the equipment to perform an urgent needle thoracostomy should be readily available.

  2. Auditory Stimulation Dishabituates Olfactory Responses via Noradrenergic Cortical Modulation

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    Jonathan J. Smith


    Full Text Available Dishabituation is a return of a habituated response if context or contingency changes. In the mammalian olfactory system, metabotropic glutamate receptor mediated synaptic depression of cortical afferents underlies short-term habituation to odors. It was hypothesized that a known antagonistic interaction between these receptors and norepinephrine ß-receptors provides a mechanism for dishabituation. The results demonstrate that a 108 dB siren induces a two-fold increase in norepinephrine content in the piriform cortex. The same auditory stimulus induces dishabituation of odor-evoked heart rate orienting bradycardia responses in awake rats. Finally, blockade of piriform cortical norepinephrine ß-receptors with bilateral intracortical infusions of propranolol (100 μM disrupts auditory-induced dishabituation of odor-evoked bradycardia responses. These results provide a cortical mechanism for a return of habituated sensory responses following a cross-modal alerting stimulus.

  3. Heart rate monitoring on the stroke unit. What does heart beat tell about prognosis? An observational study

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    Stypmann Jörg


    Full Text Available Abstract Background Guidelines recommend maintaining the heart rate (HR of acute stroke patients within physiological limits; data on the frequency and predictors of significant deviations from these limits are scarce. Methods Demographical data, stroke risk factors, NIH stroke scale score, lesion size and location, and ECG parameters were prospectively assessed in 256 patients with ischemic stroke. Patients were continuously monitored for at least 24 hours on a certified stroke unit. Tachycardia (HR ≥120 bpm and bradycardia (HR Results HR ≥120 bpm occurred in 39 patients (15%. Stroke severity (larger lesion size/higher NIHSS-score on admission, atrial fibrillation and HR on admission predicted its occurrence. HR Conclusions Significant tachycardia and bradycardia are frequent phenomena in acute stroke; however they do not independently predict clinical course or outcome. Continuous monitoring allows detecting rhythm disturbances in stroke patients and allows deciding whether urgent medical treatment is necessary.

  4. Postinduction Paced Pulseless Electrical Activity in a Patient With a History of Oropharyngeal Instrumentation–Induced Reflex Circulatory Collapse (United States)

    Kline, Ryan J.; Pham, Ky; Labrie-Brown, Carmen L.; Mancuso, Ken; LeLorier, Paul; Riopelle, James; Kaye, Alan David


    Background: Reflex hypotension and bradycardia have been reported to occur following administration of several drugs associated with administration of anesthesia and also following a variety of procedural stimuli. Case Report: A 54-year-old postmenopausal female with a history of asystole associated with sedated upper gastrointestinal endoscopy and post–anesthetic-induction tracheal intubation received advanced cardiac resuscitation after insertion of a temporary transvenous pacemaker failed to prevent pulseless electrical activity. The patient's condition stabilized, and she underwent successful cataract extraction, intraocular lens implantation, and pars plana vitrectomy. Conclusion: Cardiac pacemaker insertion prior to performance of a procedure historically associated with reflex circulatory collapse can be expected to protect a patient from bradycardia but not necessarily hypotension. PMID:27660584

  5. Transient ST-segment elevation after transseptal puncture for atrial fibrillation ablation in two cases

    Institute of Scientific and Technical Information of China (English)

    CHENG Yan-li; DONG Jian-zeng; LIU Xing-peng; LONG De-yong; FANG Dong-ping; YU Rong-hui; TANG Ri-bo; MA Chang-sheng


    The present report demonstrates two cases of transient inferior ST-segment elevation accompanied by profound hypotension and bradycardia immediately after transseptal puncture for catheter ablation of atrial fibrillation.This rare complication of transseptal puncture was resolved quickly within several minutes.The most likely mechanism of this phenomenon is coronary vasospasm,although coronary embolism can not be ruled out completely.This complication is characterized as follows:(1) The right coronary artery might be the most likely involved vessel and therefore myocardial ischemia usually occurs in the inferior wall of left ventricular; (2) Reflex hypotension and bradycardia by the Bezold-Jarisch reflex secondary to inferior ischemia often occur at the same time.Though it appears to be a transient and completely reversible phenomenon,there are still potential life-threatening risks because of myocardial ischemia and profound haemodynamic instability.Clinical cardiologists should be aware of this rare complication and properly deal with it.

  6. Amodiaquine-associated adverse effects after inadvertent overdose and after a standard therapeutic dose

    DEFF Research Database (Denmark)

    Adjei, G O; Goka, B Q; Rodrigues, O P;


    , the occurrence of bradycardia after a standard dose of amodiaquine, which coincided with the time of expected peak concentrations of the active metabolite of amodiaquine, suggests a direct drug effect. These less reported adverse effects are likely to increase in parallel with the increased use of amodiaquine......, is reported. Both subjects were homozygous for the wild type allele of cytochrome P450 2C8, the main enzyme responsible for amodiaquine metabolism. In both subjects, plasma concentrations of N-desethylamodiaquine and N-bis-desethylamodiaquine, the main metabolites of amodiaquine, were normal. No other drugs......A case of an acute dystonic reaction in a child presumptively treated for malaria with amodiaquine, and a case of persistent asymptomatic bradycardia in another child with mild pulmonary stenosis treated with a standard dose of amodiaquine for parasitologically confirmed uncomplicated malaria...

  7. Amitraz: a mimicker of organophosphate poisoning. (United States)

    Dhooria, Sahajal; Behera, Digambar; Agarwal, Ritesh


    Amitraz is used as an ectoparasiticide for dogs and cattle. Human poisoning due to amitraz may be misdiagnosed as organophosphate/carbamate (OPC) toxicity, since amitraz poisoning shares several clinical features (miosis, bradycardia and hypotension) encountered with OPC poisoning. A 19-year-old man with an alleged history of suicidal ingestion of a pesticide presented with drowsiness and was found to have constricted pupils, hypotension and bradycardia. He was diagnosed as a case of OPC poisoning and was treated with atropine and pralidoxime prior to presentation to our centre. Absence of a hypersecretory state, and the presence of hyperglycaemia and hypothermia along with a normal serum cholinesterase level suggested an alternate possibility. Retrieval of the poison container confirmed the diagnosis of amitraz poisoning. The patient made a rapid recovery with supportive management. Clinician awareness is key to successful management of this poisoning, which carries a good prognosis.

  8. Cardiac Arrest after Connecting Negative Pressure to the Subgaleal Drain during Craniotomy Closure

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    Monu Yadav


    Full Text Available A one-year-old child operated on for arachnoid cyst in right frontoparietotemporal region had sudden bradycardia followed by cardiac arrest leading to death after connecting negative pressure to the subgaleal drain during craniotomy closure. The surgical procedure was uneventful. It is a common practice to place epidural or subgaleal drains connected to a vacuum system towards the end of craniotomy to prevent accumulation of intracranial and extracranial blood. The phenomenon of bradycardia with hypotension is known to occur following negative pressure application to the epidural, epicranial, or subgaleal space after craniotomy closure. However cardiac arrest as a complication of negative pressure suction drain in neurosurgical patients is not described in the literature.

  9. Experimental Therapeutics Against the Toxic and Lethal Effects Resulting from Acute Exposure to Nerve Agents Without Carbamate Pretreatment in Guinea Pigs (United States)


    induced airway blockage and acute autonomic effects such as mucoid-salivary hypersecretion, reduced airway patency, bradycardia, atrioventricular (AV...acute agent exposure. These included oro- facial movements (indicative of immoderate secretion), mild degree of dystonia/ataxia, and a short period of...intoxicated animals. At 24 hr post-CWA exposure, both the respiratory rate and breathing patterns across Groups 6-10 were comparable to those of

  10. Electrocardiographic study in Ghanaian children with uncomplicated malaria, treated with artesunate-amodiaquine or artemether-lumefantrine

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    Adjei George O


    Full Text Available Abstract Background Several anti-malarial drugs are associated with adverse cardiovascular effects. These effects may be exacerbated when different anti-malarials are used in combination. There has been no report yet on the potential cardiac effects of the combination artesunate-amodiaquine. Methods Electrocardiographic (ECG intervals in Ghanaian children with uncomplicated malaria treated with artesunate-amodiaquine (n=47, were compared with that of children treated with artemether-lumefantrine (n=30. The ECG measurements were repeated one, two, three, seven and 28 days after treatment. The ECG intervals of artesunate-amodiaquine treated subjects were correlated with plasma concentrations of desethylamodiaquine (DEAQ, the main metabolite of amodiaquine. Results The mean ECG intervals were similar in both groups before treatment. After treatment (day 3, ECG intervals changed significantly from baseline in all subjects, but there were no differences between the two treatment groups. A significantly higher proportion of children treated with artesunate-amodiaquine developed sinus bradycardia compared with artemether-lumefantrine treated subjects (7/47 vs 0/30; χ2 p=0.03. Subjects who developed bradycardia were significantly older, and had higher DEAQ concentrations than those who did not develop bradycardia. The proportion of subjects with QTc interval prolongations did not differ significantly between the groups, and no relationship between prolonged QTc intervals and DEAQ levels were observed. No clinically significant rhythm disturbances were observed in any of the subjects. Conclusion Artesunate-amodiaquine treatment resulted in a higher incidence of sinus bradycardia than artemether-lumefantrine treatment in children with uncomplicated malaria, but no clinically significant rhythm disturbances were induced by combining artesunate with amodiaquine. These findings, although reassuring, may imply that non-amodiaquine based artemisinin

  11. Time-course effects of aerobic exercise training on cardiovascular and renal parameters in 2K1C renovascular hypertensive rats

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    R.C.A. Maia


    Full Text Available Exercise training (Ex has been recommended for its beneficial effects in hypertensive states. The present study evaluated the time-course effects of Ex without workload on mean arterial pressure (MAP, reflex bradycardia, cardiac and renal histology, and oxidative stress in two-kidney, one-clip (2K1C hypertensive rats. Male Fischer rats (10 weeks old; 150–180 g underwent surgery (2K1C or SHAM and were subsequently divided into a sedentary (SED group and Ex group (swimming 1 h/day, 5 days/week for 2, 4, 6, 8, or 10 weeks. Until week 4, Ex decreased MAP, increased reflex bradycardia, prevented concentric hypertrophy, reduced collagen deposition in the myocardium and kidneys, decreased the level of thiobarbituric acid-reactive substances (TBARS in the left ventricle, and increased the catalase (CAT activity in the left ventricle and both kidneys. From week 6 to week 10, however, MAP and reflex bradycardia in 2K1C Ex rats became similar to those in 2K1C SED rats. Ex effectively reduced heart rate and prevented collagen deposition in the heart and both kidneys up to week 10, and restored the level of TBARS in the left ventricle and clipped kidney and the CAT activity in both kidneys until week 8. Ex without workload for 10 weeks in 2K1C rats provided distinct beneficial effects. The early effects of Ex on cardiovascular function included reversing MAP and reflex bradycardia. The later effects of Ex included preventing structural alterations in the heart and kidney by decreasing oxidative stress and reducing injuries in these organs during hypertension.

  12. Acute Atrial Fibrillation Derived by Single-Doze Fentanyl Transdermal Usage

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    Mesut Gitmez


    Full Text Available Fentanyl is a selective and synthetic opiate agonist. Especially in cancer-derived pain treatment fentanyl transdermal usage is preferred. Clinic impacts occur related to several systems derived by fentanyl usage. However, respiratory failure, hypothermia and bradycardia are observed the most. In this article, we aimed at presenting a case which developed atrial fibrillation derived by single-dose fentanyl transdermal usage.

  13. Cardiac Autonomic Nerve Stimulation in the Treatment of Heart Failure


    Kobayashi, Mariko; Massiello, Alex; Karimov, Jamshid H.; Van Wagoner, David R.; Fukamachi, Kiyotaka


    Research on the therapeutic modulation of cardiac autonomic tone by electrical stimulation has yielded encouraging early clinical results. Vagus nerve stimulation has reduced the rates of morbidity and sudden death from heart failure, but therapeutic vagus nerve stimulation is limited by side effects of hypotension and bradycardia. Sympathetic nerve stimulation that has been implemented in the experiment may exacerbate the sympathetic-dominated autonomic imbalance. In contrast, concurrent sti...

  14. Development of a patch type embedded cardiac function monitoring system using dual microprocessor for arrhythmia detection in heart disease patient. (United States)

    Jang, Yongwon; Noh, Hyung Wook; Lee, I B; Jung, Ji-Wook; Song, Yoonseon; Lee, Sooyeul; Kim, Seunghwan


    A patch type embedded cardiac function monitoring system was developed to detect arrhythmias such as PVC (Premature Ventricular Contraction), pause, ventricular fibrillation, and tachy/bradycardia. The overall system is composed of a main module including a dual processor and a Bluetooth telecommunication module. The dual microprocessor strategy minimizes power consumption and size, and guarantees the resources of embedded software programs. The developed software was verified with standard DB, and showed good performance.

  15. “Fixing a heart”: the game of electrolytes in anorexia nervosa


    Abed, Jean; Judeh, Hani; Abed, Elie; Kim, Matthew; Arabelo, Haword; Gurunathan, Rajan


    Case A 25-year-old woman with chronic anorexia nervosa and depression presented with sudden weakness and fatigue. Psychosocial history was notable for binge-starve cycles over the past year and a decline in overall well-being. Vitals on presentation were notable for hypothermia, hypotension, and bradycardia. Initial exam was significant for emaciation, lethargy, and lower extremity edema. Laboratory work-up revealed markedly elevated LFTs, hypoglycemia, thrombocytopenia and elevated INR and l...

  16. An unusual presentation of mad honey poisoning: acute myocardial infarction. (United States)

    Akinci, Sinan; Arslan, Uğur; Karakurt, Kamber; Cengel, Atiye


    An unusual type of food poisoning is commonly seen in the Black Sea coast of Turkey due to grayanotoxin containing toxic honey so called "mad honey" ingestion. In cases of toxication bradycardia and rhythm disturbances are commonly observed. Herein, we present a case of a patient who was admitted to the hospital because of acute myocardial infarction with normal coronary arteries after "mad honey" ingestion.

  17. Zatosetron, a potent, selective, and long-acting 5HT3 receptor antagonist: synthesis and structure-activity relationships. (United States)

    Robertson, D W; Lacefield, W B; Bloomquist, W; Pfeifer, W; Simon, R L; Cohen, M L


    Antagonists of 5HT3 receptors are clinically effective in treating nausea and emesis associated with certain oncolytic drugs, including cisplatin. Moreover, these agents may be useful in pharmacological management of several central nervous system disorders, including anxiety, schizophrenia, dementia, and substance abuse. Our studies on aroyltropanamides led to the discovery that dihydrobenzofuranyl esters and amides are potent 5HT3 receptor antagonists. Simple benzoyl derivatives of tropine and 3 alpha-aminotropane possessed weak 5HT3 receptor antagonist activity, as judged by blockade of bradycardia produced by iv injection of serotonin (5HT) to anesthetized rats. Within this series, use of benzofuran-7-carboxamide as the aroyl moiety led to a substantial increase of 5HT3 receptor affinity. The optimal 5HT3 receptor antagonist identified via extensive SAR studies was endo-5-chloro-2,3-dihydro-2,2-dimethyl-N-(8-methyl-8-azabicyclo[3.2.1]oc t- 3-yl)-7-benzofurancarboxamide (Z)-2-butenedioate (zatosetron maleate). The 7-carbamyl regiochemistry, dimethyl substitution, chloro substituent, and endo stereochemistry were all crucial elements of the SAR. Zatosetron maleate was a potent antagonist of 5HT-induced bradycardia in rats (ED50 = 0.86 micrograms/kg i.v.). Low oral doses of zatosetron (30 micrograms/kg) produced long-lasting antagonism of 5HT3 receptors, as evidenced by blockade of 5HT-induced bradycardia for longer than 6 h in rats. Moreover, this compound did not produce hemodynamic effects after i.v. administration to rats, nor did it block carbamylcholine-induced bradycardia in doses that markedly blocked 5HT3 receptors. Thus, zatosetron is a potent, selective, orally effective 5HT3 receptor antagonist with a long duration of action in rats.

  18. Development of a Computerized Adverse Drug Event (ADE) Monitor in the Outpatient Setting (United States)


    attack) related to beta - blockers . The monitor was programmed to ignore symptom terms appearing within six words after a negation term (“not,” “ angiotensin converting enzyme inhibitors, beta - blockers , and hypoglycemic medications (both oral and injected insulin). It was determined that...bupropion) AND anorexia Benzodiazepines AND confusion Beta Blockers AND bradycardia Calcium channel blockers AND peripheral edema Diuretics AND

  19. Heart rate changes during partial seizures: A study amongst Singaporean patients

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    Lim Shih-Hui


    Full Text Available Abstract Introduction Studies in Europe and America showed that tachycardia, less often bradycardia, frequently accompanied partial seizures in Caucasian patients. We determine frequency, magnitude and type of ictal heart rate changes during partial seizures in non-Caucasian patients in Singapore. Methods Partial seizures recorded during routine EEGs performed in a tertiary hospital between 1995 and 1999 were retrospectively reviewed. All routine EEGs had simultaneous ECG recording. Heart rate before and during seizures was determined and correlated with epileptogenic focus. Differences in heart rate before and during seizures were grouped into 4 types: (1 >10% decrease; (2 -10 to +20% change; (3 20–50% increase; (3 >50% increase. Results Of the total of 37 partial seizures, 18 were left hemisphere (LH, 13 were right hemisphere (RH and 6 were bilateral (BL in onset. 51% of all seizures showed no significant change in heart rate (type 2, 22% had moderate sinus tachycardia (type 3, 11% showed severe sinus tachycardia (type 4, while 16% had sinus bradycardia (type 1. Asystole was recorded in one seizure. Apart from having more tachycardia in bilateral onset seizures, there was no correlation between side of ictal discharge and heart rate response. Compared to Caucasian patients, sinus tachycardia was considerably less frequent. Frequency of bradycardia was similar to those recorded in the literature. Conclusions Significant heart rate changes during partial seizures were seen in half of Singaporean patients. Although sinus tachycardia was the most common heart rate change, the frequency was considerably lower compared to Caucasian patients. This might be due to methodological and ethnic differences. Rates of bradycardia are similar to those recorded in the literature.

  20. G Protection by an Extreme Crouch Position. (United States)


    either side of the subject. INSTRUMENTATION The instrumentation consisted of two ECG channels, heart rate , G-profile, a low-light level TV camera (figure...physiological response was noted in these experiments. A very significant bradycardia was noted in both subjects during the G plateau: Forty heart beats per...representation of the increase and decrease of the vertical distance between heart and eyeball in different body positions. Key: d = vertical distance

  1. Endogenous RGS proteins modulate SA and AV nodal functions in isolated heart: implications for sick sinus syndrome and AV block. (United States)

    Fu, Ying; Huang, Xinyan; Piao, Lin; Lopatin, Anatoli N; Neubig, Richard R


    G protein-coupled receptors play a pivotal role in regulating cardiac automaticity. Their function is controlled by regulator of G protein signaling (RGS) proteins acting as GTPase-activating proteins for Galpha subunits to suppress Galpha(i) and Galpha(q) signaling. Using knock-in mice in which Galpha(i2)-RGS binding and negative regulation are disrupted by a genomic Galpha(i2)G184S (GS) point mutation, we recently (Fu Y, Huang X, Zhong H, Mortensen RM, D'Alecy LG, Neubig RR. Circ Res 98: 659-666, 2006) showed that endogenous RGS proteins suppress muscarinic receptor-mediated bradycardia. To determine whether this was due to direct regulation of cardiac pacemakers or to alterations in the central nervous system or vascular responses, we examined isolated, perfused hearts. Isoproterenol-stimulated beating rates of heterozygote (+/GS) and homozygote (GS/GS) hearts were significantly more sensitive to inhibition by carbachol than were those of wild type (+/+). Even greater effects were seen in the absence of isoproterenol; the potency of muscarinic-mediated bradycardia was enhanced fivefold in GS/GS and twofold in +/GS hearts compared with +/+. A(1)-adenosine receptor-mediated bradycardia was unaffected. In addition to effects on the sinoatrial node, +/GS and GS/GS hearts show significantly increased carbachol-induced third-degree atrioventricular (AV) block. Atrial pacing studies demonstrated an increased PR interval and AV effective refractory period in GS/GS hearts compared with +/+. Thus loss of the inhibitory action of endogenous RGS proteins on Galpha(i2) potentiates muscarinic inhibition of cardiac automaticity and conduction. The severe carbachol-induced sinus bradycardia in Galpha(i2)G184S mice suggests a possible role for alterations of Galpha(i2) or RGS proteins in sick sinus syndrome and pathological AV block.

  2. Isoflurane anaesthesia in an African wild dog, Lycaon pictus : short communication

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    G.F. Stegmann


    Full Text Available Anaesthesia was required in a captive female African wild dog (Lycaon pictus for surgical wound treatment. After it was immobilised with a medetomidine-ketamine combination, bradycardia, hypothermia, systolic hypertension and metabolic acidosis were observed. Surgical anaesthesia was maintained with a 1 %end-tidal isoflurane concentration. A decrease in the arterial blood pressure, rectal temperature and pHoccurred during maintenance of anaesthesia.

  3. Sleep Resilience, Comorbid Anxiety, and Treatment in a Muring Model of PTSD (United States)


    initially validated our model by showing that mice exhibit a marked bradycardia and changes in EMG activity with exposure to hypercapnia prior to modulating FC and FE and the potential of pharmacologic and behavioral interventions to impede or accelerate FE (Aims 3 & 4). The stated specific... EMG electrodes and femoral artery catheters. Protocol A: Physiological responses to the novel CS (mild transient hypercapnia, mtHC; 3.0% CO2; n

  4. Acute cardiac arrhythmias following surgery for congenital heart disease: mechanisms, diagnostic tools, and management. (United States)

    Payne, Linda; Zeigler, Vicki L; Gillette, Paul C


    This article focuses on the management of those cardiac arrhythmias most commonly seen in the immediate postoperative period. They include ventricular tachycardia, ventricular fibrillation, atrial flutter, junctional ectopic tachycardia, bradycardia, and atrioventricular block. The mechanisms of cardiac arrhythmias are reviewed followed by a brief overview of the predominant acute arrhythmias, tools used for the diagnostic evaluation of these arrhythmias, management strategies, and, finally, nursing considerations.

  5. Control of the heart rate of rat embryos during the organogenic period

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    Ritchie HE


    Full Text Available Helen E Ritchie,1 Carolina Ragnerstam,2 Elin Gustafsson,2 Johanna M Jonsson,2 William S Webster2 1Discipline of Biomedical Science, Sydney Medical School, University of Sydney, Lidcombe, 2Department of Anatomy and Histology, Sydney Medical School, University of Sydney, Sydney, NSW, Australia Abstract: The aim of this study was to gain insight into whether the first trimester embryo could control its own heart rate (HR in response to hypoxia. The gestational day 13 rat embryo is a good model for the human embryo at 5–6 weeks gestation, as the heart is comparable in development and, like the human embryo, has no functional autonomic nerve supply at this stage. Utilizing a whole-embryo culture technique, we examined the effects of different pharmacological agents on HR under normoxic (95% oxygen and hypoxic (20% oxygen conditions. Oxygen concentrations ≤60% caused a concentration-dependent decrease in HR from normal levels of ~210 bpm. An adenosine agonist, AMP-activated protein kinase (AMPK activator and KATP channel opener all caused bradycardia in normoxic conditions; however, putative antagonists for these systems failed to prevent or ameliorate hypoxia-induced bradycardia. This suggests that the activation of one or more of these systems is not the primary cause of the observed hypoxia-induced bradycardia. Inhibition of oxidative phosphorylation also decreased HR in normoxic conditions, highlighting the importance of ATP levels. The β-blocker metoprolol caused a concentration-dependent reduction in HR supporting reports that β1-adrenergic receptors are present in the early rat embryonic heart. The cAMP inducer colforsin induced a positive chronotropic effect in both normoxic and hypoxic conditions. Overall, the embryonic HR at this stage of development is responsive to the level of oxygenation, probably as a consequence of its influence on ATP production. Keywords: embryonic heart rate, embryo, bradycardia, in vitro, ATP, hypoxia

  6. Nasocardiac reflex during aspiration and injection through a nasogastric tube: An infrequent occurrence. (United States)

    Haldar, Rudrashish; Kaur, Jasleen; Bajwa, Sukhminder Jit Singh


    Nasocardiac reflex is a relatively less discussed variant of trigeminovagal reflex where the afferent arc of the reflex is represented by any of the branches of the trigeminal nerves, and the efferent arc is via the vagus nerve. Elicitation of this reflex is commonly seen during surgical manipulation and is manifested as bradycardia or even asystole. We report a case where nasocardiac reflex was unusually observed in a patient when aspiration and injection were done through a nasogastric tube.

  7. Antihypertensive responses elicited by central moxonidine in rats: Possible role of nitric oxide


    Moreira, Thiago Santos [UNIFESP; Takakura, Ana Carolina Thomaz [UNIFESP; Sato, Monica Akemi; Menani, Jose Vanderlei; Colombari, Eduardo


    In the present study, we investigated the effects of pretreatment with N-G-nitro-L-arginine methyl ester (L-NAME) (nitric oxide synthase inhibitor) injected intravenously (IV) on the hypotension, bradycardia, and vasodilation produced by moxonidine (alpha(2)-adrenergic/imidazoline receptor agonist) injected into the fourth brain ventricle (4th V) in rats submitted to acute hypertension that results from baroreflex blockade by bilateral injections of kynurenic acid (kyn, glutamatergic receptor...

  8. Central blockade of nitric oxide synthesis reduces moxonidine-induced hypotension


    Moreira, Thiago Santos [UNIFESP; Takakura, Ana Carolina Thomaz [UNIFESP; Menani, José V.; Sato, Monica Akemi; Colombari, Eduardo


    1 Nitric oxide (NO) and alpha(2)-adrenoceptor and imidazoline agonists such as moxonidine may act centrally to inhibit sympathetic activity and decrease arterial pressure.2 In the present study, we investigated the effects of pretreatment with L-NAME ( NO synthesis inhibitor), injected into the 4th ventricle (4th V) or intravenously (i.v.), on the hypotension, bradycardia and vasodilatation induced by moxonidine injected into the 4th V in normotensive rats.3 Male Wistar rats with a stainless ...

  9. Neurogenic Shock Immediately following Posterior Lumbar Interbody Fusion: Report of Two Cases


    Matsumoto, Tomiya; Okuda, Shinya; Haku, Takamitsu; Maeda, Kazuya; Maeno, Takafumi; Yamashita, Tomoya; Yamasaki, Ryoji; Kuratsu, Shigeyuki; Iwasaki, Motoki


    Study Design Case report. Objective To present two cases of neurogenic shock that occurred immediately following posterior lumbar interbody fusion (PLIF) and that appeared to have been caused by the vasovagal reflex after dural injury and incarceration of the cauda equina. Case Report We present two cases of neurogenic shock that occurred immediately following PLIF. One patient had bradycardia, and the other developed cardiac arrest just after closing the surgical incision and opening the dra...

  10. Cardiovascular complications in ciguatera fish poisoning: A wake-up call

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    Subramanian Senthilkumaran


    Full Text Available Ciguatera fish poisoning occurs with ingestion of fish containing ciguatoxin. It causes a clinical syndrome that comprises classic gastrointestinal, neurological and cardiovascular symptoms. Ciguatoxin is a sodium channel agonist with cholinergic and adrenergic activity. Although cardiovascular symptoms are rare with ciguatoxin, we report two cases with bradycardia and hypotension. Fatality and long-term sequelae are not uncommon with ciguatoxin poisoning and educating the general population is essential.

  11. Biological Parameters of Impact (United States)


    zone between no effect and gross injury or death . For example, the pilot who survives an aircraft crash, but who is injured or unconscious so that he...Biological effects were limited to one incidence of bradycardia (116 t36 t and three instances of premature ventricular contractions. However. subjeCtiY" I...R.F.Chandler INTRODUCTION -Investigation of the biological effects of abrupt acceleration (impact) was stimulated by the advent of technical advances

  12. Inactivation of the central nucleus of the amygdala blocks classical conditioning but not conditioning-specific reflex modification of rabbit heart rate. (United States)

    Burhans, Lauren B; Schreurs, Bernard G


    Heart rate (HR) conditioning in rabbits is a widely used model of classical conditioning of autonomic responding that is noted for being similar to the development of conditioned heart rate slowing (bradycardia) in humans. We have shown previously that in addition to HR changes to a tone conditioned stimulus (CS), the HR reflex itself can undergo associative change called conditioning-specific reflex modification (CRM) that manifests when tested in the absence of the CS. Because CRM resembles the conditioned bradycardic response to the CS, we sought to determine if HR conditioning and CRM share a common neural substrate. The central nucleus of the amygdala (CeA) is a critical part of the pathway through which conditioned bradycardia is established. To test whether the CeA is also involved in the acquisition and/or expression of CRM, we inactivated the CeA with muscimol during HR conditioning or CRM testing. CeA inactivation blocked HR conditioning without completely preventing CRM acquisition or expression. These results suggest that the CeA may therefore only play a modulatory role in CRM. Theories on the biological significance of conditioned bradycardia suggest that it may represent a state of hypervigilance that facilitates the detection of new and changing contingencies in the environment. We relate these ideas to our results and discuss how they may be relevant to the hypersensitivity observed in fear conditioning disorders like post-traumatic stress.


    Crăcană, Irina; Vasilcu, T F; Mardare, Alexandra; Alexa, Ioana Dana; Marcu, D T M


    Sinus node dysfunction is one of the most common arrhythmias in elderly patients; it is usually associated with intermittent and variable symptoms, thus making it difficult to diagnose. We present the case of an elderly female patient with a personal history of atrial fibrillation treated for the last three years with amiodarone; she was admitted to the Geriatric Clinic for non-specific symptoms with onset two months previously for which she had already sought care in different medical services. Clinical examination showed severe bradycardia; ECG and Holter ECG on admission confirmed severe bradycardia, with a heart rate between 29 and 50 beats/min (bpm). Given her long-term treatment with amiodarone we looked for and found hyperthyroidism; the endocrine examination led to the diagnosis of mixed type Amiodarone-induced thyrotoxicosis and initiation of corticosteroid and antithyroid treatment. The evolution of cardiac arrhythmia was monitored with the help of several Holter ECGs performed after amiodarone washout and return to the euthyroid state, which revealed a tachycardia-bradycardia syndrome initially masked by the side effects of the unsupervised therapy with amiodarone, and properly treated by the implantation of a pacemaker.

  14. Effects of local anesthesia of the cerebellum on classical fear conditioning in goldfish

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    Hirano Ruriko


    Full Text Available Abstract Background Besides the amygdala, of which emotion roles have been intensively studied, the cerebellum has also been demonstrated to play a critical role in simple classical fear conditioning in both mammals and fishes. In the present study, we examined the effect of local administration of the anesthetic agent lidocaine into the cerebellum on fear-related, classical heart-rate conditioning in goldfish. Methods The effects of microinjection of the anesthetic agent lidocaine into the cerebellum on fear conditioning were investigated in goldfish. The fear conditioning paradigm was delayed classical conditioning with light as a conditioned stimulus and electric shock as an unconditioned stimulus; cardiac deceleration (bradycardia was the conditioned response. Results Injecting lidocaine into the cerebellum had no effect on the base heart rate, an arousal/orienting response to the novel stimulus (i.e., the first presentation of light, or an unconditioned response to electric shock. However, lidocaine injection greatly impaired acquisition of conditioned bradycardia. Lidocaine injection 60 min before the start of the conditioning procedure showed no effect on acquisition of conditioned bradycardia, indicating that the effect of lidocaine was reversible. Conclusions The present results further confirm the idea that the cerebellum in teleost fish, as in mammals, is critically involved in classical fear conditioning.

  15. Trigemino-cardiac reflex during skull-base neurosurgeries: a case report

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    Mohammad Reza Khajavi


    Full Text Available Background: The Trigemino-cardiac reflex (TCR has been studied as a phenomenon including; bradycardia, arterial hypotension, apnea and gastric hypermotility during manipulation of the peripheral or central parts of the trigeminal nerve.Case presentation: We report a case of a 26-year-old man undergoing surgery for a skull base extra axial tumor in right petrous bone suspected to metastasis of a previous renal cell carcinoma which had been treated four years ago. The patient presented with continuous and unilateral headache and difficulty in swallowing, sensory neural hearing loss, nasal speech and tongue deviation to left side. He underwent general anesthesia with standard monitoring and total intravenous anesthetic technique. The first episode of sudden onset bradycardia and hypotension related to surgical manipulation was detected intraoperatively in which the heart rate spontaneously returned to normal level once the surgical manipulation stopped. However, it repeated several times by beginning of tumor resection and manipulation in the region of trigeminal nerve. The intensity of bradycardia in subsequent episodes of TCR was relatively crescendo and had no fatigability. Finally, it was treated by administration of a single dose of atropine (0.5mg/IV and did not happen again.Conclusion: The risk of TCR should be considered in any neurosurgical intervention involving trigeminal nerve and its branches, especially at the skull base surgeries. The vigilance of the medical team and continuous intraoperative hemodynamic monitoring alerts the surgeons to interrupt surgical maneuvers upon the TCR occurrence, immediately.

  16. BRADICARDIA SINTOMÁTICA Y USO DE MARCAPASOS EN EL SERVICIO DE URGENCIAS Symptomatic bradicardia and pacemaker use in the emergency room

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    Full Text Available Los marcapasos son aparatos universalmente aceptados para el manejo temporal o definitivo de diferentes tipos de bradicardia sintomática. A los servicios de urgencias consultan con frecuencia pacientes con síntomas que pueden o no estar asociados con bradicardia. En muchos casos la frecuencia cardíaca es demasiado baja y se acompaña de signos de bajo gasto, como son estado mental alterado, dolor torácico, hipotensión, mala perfusión tisular, falla cardíaca, convulsiones, síncope o choque, que pueden comprometer la vida del paciente. Saber reconocer las situaciones de emergencia relacionadas con las bradiarritmias y manejarlas de manera oportuna, es uno de los retos del médico de urgencias.Pacemakers are universally accepted devices used for the management of symptomatic bradycardia. Their use can be temporal or indefinite. Many patients assist to the emergency room service with symptoms that can or can not be associated with bradycardia. Sometimes the heart rate is too slow, and patients have signs and symptoms ase: acute alteration mental status, chest pain, hypotension, congestive heart failure, seizures, syncope or shock. These situations can compromise patients' life. Identify those emergency cases related with bradycardia and to take the correct decisions are a total challenge for emergency.

  17. Early heart failure in the SMNDelta7 model of spinal muscular atrophy and correction by postnatal scAAV9-SMN delivery. (United States)

    Bevan, Adam K; Hutchinson, Kirk R; Foust, Kevin D; Braun, Lyndsey; McGovern, Vicki L; Schmelzer, Leah; Ward, Jennifer G; Petruska, Jeffrey C; Lucchesi, Pamela A; Burghes, Arthur H M; Kaspar, Brian K


    Proximal spinal muscular atrophy (SMA) is a debilitating neurological disease marked by isolated lower motor neuron death and subsequent atrophy of skeletal muscle. Historically, SMA pathology was thought to be limited to lower motor neurons and the skeletal muscles they control, yet there are several reports describing the coincidence of cardiovascular abnormalities in SMA patients. As new therapies for SMA emerge, it is necessary to determine whether these non-neuromuscular systems need to be targeted. Therefore, we have characterized left ventricular (LV) function of SMA mice (SMN2+/+; SMNΔ7+/+; Smn-/-) and compared it with that of their unaffected littermates at 7 and 14 days of age. Anatomical and physiological measurements made by electrocardiogram and echocardiography show that affected mouse pups have a dramatic decrease in cardiac function. At 14 days of age, SMA mice have bradycardia and develop a marked dilated cardiomyopathy with a concomitant decrease in contractility. Signs of decreased cardiac function are also apparent as early as 7 days of age in SMA animals. Delivery of a survival motor neuron-1 transgene using a self-complementary adeno-associated virus serotype 9 abolished the symptom of bradycardia and significantly decreased the severity of the heart defect. We conclude that severe SMA animals have compromised cardiac function resulting at least partially from early bradycardia, which is likely attributable to aberrant autonomic signaling. Further cardiographic studies of human SMA patients are needed to clarify the clinical relevance of these findings from this SMA mouse.

  18. Patterns of heart rate responses to hydralazine in normotensive and hypertensive rats. (United States)

    Vidrio, H


    Hydralazine (H) induces hypotension accompanied by cardiac stimulation due to activation of the arterial baroreflex. Both clinical and experimental observations suggest, however, that in certain conditions H hypotension can be accompanied by unchanged or even depressed cardiac performance. The present study determined whether varying patterns of heart rate responses could be detected in large populations of conscious normotensive (n = 61) and renal hypertensive (n = 59) rats receiving a single dose of H. These patterns were compared with those of normotensive pentobarbital-anesthetized rats (n = 43). In the three groups, hypotension was accompanied by either tachycardia, unchanged heart rate or bradycardia. Tachycardia was found in 52% of normotensive conscious rats, in 51% of hypertensives and in only 14% of anesthetized animals. Heart rate did not change in 26, 35 and 23%, while bradycardia was detected in 22, 14 and 63%, respectively. These results were explained by postulating the initiation by H of two reflexes with opposite effects on heart rate: the arterial baroreflex producing tachycardia and a cardiac mechanoreceptor reflex producing bradycardia. These reactions would compete with each other, with results depending on their relative sensitivity in a given animal.

  19. Central blockade of nitric oxide synthesis reduces moxonidine-induced hypotension. (United States)

    Moreira, Thiago Santos; Takakura, Ana Carolina Thomaz; Menani, José V; Sato, Monica Akemi; Colombari, Eduardo


    1. Nitric oxide (NO) and alpha(2)-adrenoceptor and imidazoline agonists such as moxonidine may act centrally to inhibit sympathetic activity and decrease arterial pressure. 2. In the present study, we investigated the effects of pretreatment with l-NAME (NO synthesis inhibitor), injected into the 4th ventricle (4th V) or intravenously (i.v.), on the hypotension, bradycardia and vasodilatation induced by moxonidine injected into the 4th V in normotensive rats. 3. Male Wistar rats with a stainless steel cannula implanted into the 4th V and anaesthetized with urethane were used. Blood flows were recorded by use of miniature pulsed Doppler flow probes implanted around the renal, superior mesenteric and low abdominal aorta. 4. Moxonidine (20 nmol), injected into the 4th V, reduced the mean arterial pressure (-42+/-3 mmHg), heart rate (-22+/-7 bpm) and renal (-62+/-15%), mesenteric (-41+/-8%) and hindquarter (-50+/-8%) vascular resistances. 5. Pretreatment with l-NAME (10 nmol into the 4th V) almost abolished central moxonidine-induced hypotension (-10+/-3 mmHg) and renal (-10+/-4%), mesenteric (-11+/-4%) and hindquarter (-13+/-6%) vascular resistance reduction, but did not affect the bradycardia (-18+/-8 bpm). 6. The results indicate that central NO mechanisms are involved in the vasodilatation and hypotension, but not in the bradycardia, induced by central moxonidine in normotensive rats.

  20. Blocked Atrial Bi/Trigeminy In Utero Evolving in Supraventricular Tachycardia after Birth

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    V. Martucci


    Full Text Available Transient episodes of fetal bradycardia (heart rate less than 110 bpm are usually benign and typically result from increased vagal stimulation in the fetus. Causes of sustained fetal bradycardia include sinus bradycardia, blocked atrial bigeminy/trigeminy, high-degree atrioventricular block, and long QT syndrome. We present the case of a 34-year-old Caucasian patient referred to our department for “blocked atrial bigeminy with pseudobradycardia” detected elsewhere at 33 weeks of gestation. A fetal echocardiography showed during all the examination a blocked atrial trigeminy with a mean fetal heart rate of 100 bpm. After birth three subsequent ECGs until day 3 showed no evidence of atrial extrasystoles, confirming the well-known frequent regression of this kind of fetal benign arrhythmia, but on day 11 recurrence of supraventricular trigeminy and development of episodes of paroxystic supraventricular tachycardia were observed. On the basis of this observation, we recommend that fetuses with complex atrial ectopic beats should be closely monitored before and after birth for evidence of new arrhythmias.

  1. Randomized Trial of a Novel ACLS Teaching Tool: Does it Improve Student Performance?

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    Nicholas Nacca


    Full Text Available Introduction: Mounting evidence suggests that high-fidelity mannequin-based (HFMBS and computer-based simulation are useful adjunctive educational tools for advanced cardiac life support (ACLS instruction. We sought to determine whether access to a supplemental, online computer-based ACLS simulator would improve students’ performance on a standardized Mega Code using high-fidelity mannequin based simulation (HFMBS. Methods: Sixty-five third-year medical students were randomized. Intervention group subjects (n = 29 each received a two-week access code to the online ACLS simulator, whereas the control group subjects (n = 36 did not. Primary outcome measures included students’ time to initiate chest compressions, defibrillate ventricular fibrillation, and pace symptomatic bradycardia. Secondary outcome measures included students’ subjective self-assessment of ACLS knowledge and confidence. Results: Students with access to the online simulator on average defibrillated ventricular fibrillation in 112 seconds, whereas those without defibrillated in 149.9 seconds, an average of 38 seconds faster [p<.05]. Similarly, those with access to the simulator paced symptomatic bradycardia on average in 95.14 seconds whereas those without access paced on average 154.9 seconds a difference of 59.81 seconds [p<.05]. On a subjective 5-point scale, there was no difference in self-assessment of ACLS knowledge between the control (mean 3.3 versus intervention (mean 3.1 [p-value =.21]. Despite having outperformed the control group subjects in the standardized Mega Code test scenario, the intervention group felt less confident on a 5-point scale (mean 2.5 than the control group. (mean 3.2 [p<.05] Conclusion: The reduction in time to defibrillate ventricular fibrillation and to pace symptomatic bradycardia among the intervention group subjects suggests that the online computer-based ACLS simulator is an effective adjunctive ACLS instructional tool. [West J Emerg Med

  2. Experts Consensus Recommendations for the Management of Calcium Channel Blocker Poisoning in Adults (United States)

    Anseeuw, Kurt; Cantrell, Frank Lee; Gilchrist, Ian C.; Hantson, Philippe; Bailey, Benoit; Lavergne, Valéry; Gosselin, Sophie; Kerns, William; Laliberté, Martin; Lavonas, Eric J.; Juurlink, David N.; Muscedere, John; Yang, Chen-Chang; Sinuff, Tasnim; Rieder, Michael; Mégarbane, Bruno


    Objective: To provide a management approach for adults with calcium channel blocker poisoning. Data Sources, Study Selection, and Data Extraction: Following the Appraisal of Guidelines for Research & Evaluation II instrument, initial voting statements were constructed based on summaries outlining the evidence, risks, and benefits. Data Synthesis: We recommend 1) for asymptomatic patients, observation and consideration of decontamination following a potentially toxic calcium channel blocker ingestion (1D); 2) as first-line therapies (prioritized based on desired effect), IV calcium (1D), high-dose insulin therapy (1D–2D), and norepinephrine and/or epinephrine (1D). We also suggest dobutamine or epinephrine in the presence of cardiogenic shock (2D) and atropine in the presence of symptomatic bradycardia or conduction disturbance (2D); 3) in patients refractory to the first-line treatments, we suggest incremental doses of high-dose insulin therapy if myocardial dysfunction is present (2D), IV lipid-emulsion therapy (2D), and using a pacemaker in the presence of unstable bradycardia or high-grade arteriovenous block without significant alteration in cardiac inotropism (2D); 4) in patients with refractory shock or who are periarrest, we recommend incremental doses of high-dose insulin (1D) and IV lipid-emulsion therapy (1D) if not already tried. We suggest venoarterial extracorporeal membrane oxygenation, if available, when refractory shock has a significant cardiogenic component (2D), and using pacemaker in the presence of unstable bradycardia or high-grade arteriovenous block in the absence of myocardial dysfunction (2D) if not already tried; 5) in patients with cardiac arrest, we recommend IV calcium in addition to the standard advanced cardiac life-support (1D), lipid-emulsion therapy (1D), and we suggest venoarterial extracorporeal membrane oxygenation if available (2D). Conclusion: We offer recommendations for the stepwise management of calcium channel blocker

  3. Exercise training changes autonomic cardiovascular balance in mice. (United States)

    De Angelis, K; Wichi, R B; Jesus, W R A; Moreira, E D; Morris, M; Krieger, E M; Irigoyen, M C


    Experiments were performed to investigate the influence of exercise training on cardiovascular function in mice. Heart rate, arterial pressure, baroreflex sensitivity, and autonomic control of heart rate were measured in conscious, unrestrained male C57/6J sedentary (n = 8) and trained mice (n = 8). The exercise training protocol used a treadmill (1 h/day; 5 days/wk for 4 wk). Baroreflex sensitivity was evaluated by the tachycardic and bradycardic responses induced by sodium nitroprusside and phenylephrine, respectively. Autonomic control of heart rate and intrinsic heart rate were determined by use of methylatropine and propranolol. Resting bradycardia was observed in trained mice compared with sedentary animals [485 +/- 9 vs. 612 +/- 5 beats/min (bpm)], whereas mean arterial pressure was not different between the groups (106 +/- 2 vs. 108 +/- 3 mmHg). Baroreflex-mediated tachycardia was significantly enhanced in the trained group (6.97 +/- 0.97 vs. 1.6 +/- 0.21 bpm/mmHg, trained vs. sedentary), whereas baroreflex-mediated bradycardia was not altered by training. The tachycardia induced by methylatropine was significantly increased in trained animals (139 +/- 12 vs. 40 +/- 9 bpm, trained vs. sedentary), whereas the propranolol effect was significantly reduced in the trained group (49 +/- 11 vs. 97 +/- 11 bpm, trained vs. sedentary). Intrinsic heart rate was similar between groups. In conclusion, dynamic exercise training in mice induced a resting bradycardia and an improvement in baroreflex-mediated tachycardia. These changes are likely related to an increased vagal and decreased sympathetic tone, similar to the exercise response observed in humans.

  4. Enhanced negative chronotropy by inhibitory receptors in transgenic heart overexpressing beta(2)-adrenoceptors. (United States)

    Du, X J; Vincan, E; Percy, E; Woodcock, E A


    Transgenic (TG) mice overexpressing beta(2)-adrenoceptors (AR) in the heart have enhanced beta-adrenergic activity. Since the degree of beta-adrenergic activation influences the negative chronotropic control of heart rate (HR), we studied the inhibitory effect of cholinergic and purinergic stimulation on HR in TG and wild-type (WT) control mice. Bradycardia in response to vagal nerve stimulation and administration of acetylcholine or adenosine was studied in anesthetised animals and perfused hearts. Basal HR was significantly higher in TG than WT mice (P<0.01). Electrical stimulation of vagal nerves (1-32 Hz) induced a Hz-dependent reduction in HR and the response was more pronounced in TG than WT groups (P<0.01). In perfused hearts, HR reduction by acetylcholine (ACh) was more pronounced with EC(50) 110-fold lower in TG than WT hearts. Adenosine-induced bradycardia, which was abolished by a P(1) antagonist, was more pronounced in TG hearts. After pre-treatment with pertussis toxin (PT, 100 microg/kg), bradycardia by vagal nerve stimulation or ACh remained unchanged in WT, but markedly inhibited in TG hearts (both P<0.01). Conversely, inhibiting guanylyl cyclase with LY83583 (30 microM) or nitric oxide synthase with L-NMMA (100 microM) attenuated HR reduction by vagal nerve stimulation in WT but not in TG hearts. Immunobloting assay showed similar G(ialpha2) abundance in TG and WT hearts. Thus, cardiac overexpression of beta(2)AR with high beta-adrenergic activity leads to hypersensitivity of inhibitory receptors controlling HR due to increase in activity of PT-sensitive G-proteins.

  5. Central-peripheral neural network interactions evoked by vagus nerve stimulation: functional consequences on control of cardiac function. (United States)

    Ardell, Jeffrey L; Rajendran, Pradeep S; Nier, Heath A; KenKnight, Bruce H; Armour, J Andrew


    Using vagus nerve stimulation (VNS), we sought to determine the contribution of vagal afferents to efferent control of cardiac function. In anesthetized dogs, the right and left cervical vagosympathetic trunks were stimulated in the intact state, following ipsilateral or contralateral vagus nerve transection (VNTx), and then following bilateral VNTx. Stimulations were performed at currents from 0.25 to 4.0 mA, frequencies from 2 to 30 Hz, and a 500-μs pulse width. Right or left VNS evoked significantly greater current- and frequency-dependent suppression of chronotropic, inotropic, and lusitropic function subsequent to sequential VNTx. Bradycardia threshold was defined as the current first required for a 5% decrease in heart rate. The threshold for the right vs. left vagus-induced bradycardia in the intact state (2.91 ± 0.18 and 3.47 ± 0.20 mA, respectively) decreased significantly with right VNTx (1.69 ± 0.17 mA for right and 3.04 ± 0.27 mA for left) and decreased further following bilateral VNTx (1.29 ± 0.16 mA for right and 1.74 ± 0.19 mA for left). Similar effects were observed following left VNTx. The thresholds for afferent-mediated effects on cardiac parameters were 0.62 ± 0.04 and 0.65 ± 0.06 mA with right and left VNS, respectively, and were reflected primarily as augmentation. Afferent-mediated tachycardias were maintained following β-blockade but were eliminated by VNTx. The increased effectiveness and decrease in bradycardia threshold with sequential VNTx suggest that 1) vagal afferents inhibit centrally mediated parasympathetic efferent outflow and 2) the ipsilateral and contralateral vagi exert a substantial buffering capacity. The intact threshold reflects the interaction between multiple levels of the cardiac neural hierarchy.

  6. The bradycardic and hypotensive responses to serotonin are reduced by activation of GABA A receptors in the nucleus tractus solitarius of awake rats

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    J.C. Callera


    Full Text Available We investigated the effects of bilateral injections of the GABA receptor agonists muscimol (GABA A and baclofen (GABA B into the nucleus tractus solitarius (NTS on the bradycardia and hypotension induced by iv serotonin injections (5-HT, 2 µg/rat in awake male Holtzman rats. 5-HT was injected in rats with stainless steel cannulas implanted bilaterally in the NTS, before and 5, 15, and 60 min after bilateral injections of muscimol or baclofen into the NTS. The responses to 5-HT were tested before and after the injection of atropine methyl bromide. Muscimol (50 pmol/50 nl, N = 8 into the NTS increased basal mean arterial pressure (MAP from 115 ± 4 to 144 ± 6 mmHg, did not change basal heart rate (HR and reduced the bradycardia (-40 ± 14 and -73 ± 26 bpm at 5 and 15 min, respectively, vs -180 ± 20 bpm for the control and hypotension (-11 ± 4 and -14 ± 4 mmHg, vs -40 ± 9 mmHg for the control elicited by 5-HT. Baclofen (12.5 pmol/50 nl, N = 7 into the NTS also increased basal MAP, but did not change basal HR, bradycardia or hypotension in response to 5-HT injections. Atropine methyl bromide (1 mg/kg body weight injected iv reduced the bradycardic and hypotensive responses to 5-HT injections. The stimulation of GABA A receptors in the NTS of awake rats elicits a significant increase in basal MAP and decreases the cardiac Bezold-Jarisch reflex responses to iv 5-HT injections.

  7. Resuscitator’s perceptions and time for corrective ventilation steps during neonatal resuscitation☆ (United States)

    Sharma, Vinay; Lakshminrusimha, Satyan; Carrion, Vivien; Mathew, Bobby


    Background The 2010 neonatal resuscitation program (NRP) guidelines incorporate ventilation corrective steps (using the mnemonic – MRSOPA) into the resuscitation algorithm. The perception of neonatal providers, time taken to perform these maneuvers or the effectiveness of these additional steps has not been evaluated. Methods Using two simulated clinical scenarios of varying degrees of cardiovascular compromise –perinatal asphyxia with (i) bradycardia (heart rate – 40 min−1) and (ii) cardiac arrest, 35 NRP certified providers were evaluated for preference to performing these corrective measures, the time taken for performing these steps and time to onset of chest compressions. Results The average time taken to perform ventilation corrective steps (MRSOPA) was 48.9 ± 21.4 s. Providers were less likely to perform corrective steps and proceed directly to endotracheal intubation in the scenario of cardiac arrest as compared to a state of bradycardia. Cardiac compressions were initiated significantly sooner in the scenario of cardiac arrest 89 ± 24 s as compared to severe bradycardia 122 ± 23 s, p < 0.0001. There were no differences in the time taken to initiation of chest compressions between physicians or mid-level care providers or with the level of experience of the provider. Conclusions Effective ventilation of the lungs with corrective steps using a mask is important in most cases of neonatal resuscitation. Neonatal resuscitators prefer early endotracheal intubation and initiation of chest compressions in the presence of asystolic cardiac arrest. Corrective ventilation steps can potentially postpone initiation of chest compressions and may delay return of spontaneous circulation in the presence of severe cardiovascular compromise. PMID:25796996

  8. Comparative effects of sodium channel blockers in short term rat whole embryo culture

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    Nilsson, Mats F, E-mail: [Department of Pharmaceutical Biosciences, Uppsala University (Sweden); Sköld, Anna-Carin; Ericson, Ann-Christin; Annas, Anita; Villar, Rodrigo Palma [AstraZeneca R and D Södertälje (Sweden); Cebers, Gvido [AstraZeneca R and D, iMed, 141 Portland Street, Cambridge, MA 02139 (United States); Hellmold, Heike; Gustafson, Anne-Lee [AstraZeneca R and D Södertälje (Sweden); Webster, William S [Department of Anatomy and Histology, University of Sydney (Australia)


    This study was undertaken to examine the effect on the rat embryonic heart of two experimental drugs (AZA and AZB) which are known to block the sodium channel Nav1.5, the hERG potassium channel and the L-type calcium channel. The sodium channel blockers bupivacaine, lidocaine, and the L-type calcium channel blocker nifedipine were used as reference substances. The experimental model was the gestational day (GD) 13 rat embryo cultured in vitro. In this model the embryonic heart activity can be directly observed, recorded and analyzed using computer assisted image analysis as it responds to the addition of test drugs. The effect on the heart was studied for a range of concentrations and for a duration up to 3 h. The results showed that AZA and AZB caused a concentration-dependent bradycardia of the embryonic heart and at high concentrations heart block. These effects were reversible on washout. In terms of potency to cause bradycardia the compounds were ranked AZB > bupivacaine > AZA > lidocaine > nifedipine. Comparison with results from previous studies with more specific ion channel blockers suggests that the primary effect of AZA and AZB was sodium channel blockage. The study shows that the short-term rat whole embryo culture (WEC) is a suitable system to detect substances hazardous to the embryonic heart. - Highlights: • Study of the effect of sodium channel blocking drugs on embryonic heart function • We used a modified method rat whole embryo culture with image analysis. • The drugs tested caused a concentration dependent bradycardia and heart block. • The effect of drugs acting on multiple ion channels is difficult to predict. • This method may be used to detect cardiotoxicity in prenatal development.

  9. A novel approach to assessing percutaneous VX poisoning in the conscious guinea-pig. (United States)

    Mumford, Helen; Price, Matthew E; Wetherell, Janet R


    Nerve agents like VX (S-2-diisopropylaminoethyl-O-ethyl-methylphosphonothiolate) are potent irreversible acetylcholinesterase (AChE) inhibitors. Following percutaneous nerve agent exposure there is a slower rate of absorption, later onset and longer duration of signs of poisoning. Relatively little is known about the physiological effects of percutaneously applied nerve agent in unanaesthetised laboratory animals. Heart rate (ECG), brain electrical activity (EEG), body temperature, locomotor activity and clinical signs were monitored following percutaneous application of VX to conscious guinea-pigs.A fall in heart rate (bradycardia) preceded incapacitation following the highest VX dose, and occurred in the absence of incapacitation at the lower doses. Following the highest dose of VX (0.592 mg kg(-1)) three out of four animals died within 24 h. The lower two doses of VX (0.296 and 0.148 mg kg(-1)), produced extended periods of bradycardia in the absence of observable signs of poisoning. Bradycardia preceded, or occurred in the absence of, a temperature decrease; seizure-like EEG changes were not observed at any of the VX doses tested. Acetylcholinesterase activity was significantly inhibited in the blood and most brain areas at 48 h. There were significant dose-related decreases in body weight at 24 and 48 h following VX. This preliminary study suggests that decreased heart rate may be an early sign of the toxic effects of VX, whereas temperature and observable clinical signs are not good early indicators of percutaneous VX poisoning in this animal model. Future studies will use this model to assess the benefit of administering medical countermeasures in response to a defined decrease in heart rate.

  10. Mechanisms contributing to the regional haemodynamic effects of neurotensin in conscious, unrestrained Long Evans rats. (United States)

    Bachelard, H; Gardiner, S M; Kemp, P A; Bennett, T


    1. The regional haemodynamic effects of i.v. bolus doses of neurotensin (10-1000 ng) were assessed in conscious, unrestrained Long Evans rats chronically instrumented with miniaturized, pulsed Doppler probes. 2. Neurotensin caused increases in blood pressure, together with dose-related tachycardias and constrictions in the renal, superior mesenteric and hindquarters vascular beds. The tachycardia elicited by the 1000 ng dose of neurotensin was preceded by a transient bradycardia. 3. In the presence of phentolamine, the pressor effect of neurotensin (1000 ng) was converted into a hypotensive effect, accompanied by reduced tachycardic and constrictor responses in the renal, superior mesenteric and hindquarters vascular beds. The tachycardia was not preceded by a bradycardia. 4. In the presence of phentolamine and propranolol, the pressor and bradycardic responses to neurotensin were unaffected, whereas the tachycardia was abolished. The renal vasconstrictor effect was smaller, while the constrictions in the superior mesenteric and hindquarters vascular beds were not different from those in untreated rats. 5. In rats neonatally treated with capsaicin (50 mg kg-1, s.c.), the pressor effects elicited by neurotensin (300 and 1000 ng) were reduced as were the constrictor responses in the renal (at the dose of 300 ng), superior mesenteric (at the dose of 300 ng) and hindquarters (at both doses) vascular beds. The bradycardia elicited by neurotensin (1000 ng) was absent, whereas the tachycardia was potentiated. 6. The results indicate that in conscious, intact rats neurotensin appears to exert cardiovascular influences through activation of sympathoadrenal mechanisms and also through non-adrenergic effects on the heart, renal, superior mesenteric and hindquarters vascular beds. The latter effects appear to involve capsaicin-sensitive nerves.

  11. Lung ultrasound-guided emergency pneumothorax needle aspiration in a very preterm infant. (United States)

    Migliaro, Fiorella; Sodano, Angela; Capasso, Letizia; Raimondi, Francesco


    Pneumothorax is a frequent critical situation in the neonatal intensive care unit. Diagnosis relies on clinical judgement, transillumination and chest radiogram. We report the case of a very preterm infant suddenly developing significant and persistent desaturation and bradycardia. Re-intubation and cardiopulmonary resuscitation were performed. Clinical and cold light examination were not suggestive of pneumothorax according to two experienced neonatologists. A lung ultrasound scan showed evidence of right pneumothorax that was promptly aspirated. Approximately 20 min later, a chest radiogram confirmed the ultrasound diagnosis. Point-of-care lung ultrasound is a useful tool for detecting symptomatic pneumothorax and accelerating its treatment.

  12. [Thalidomide-associated hypothyroidism in a patient with multiple myeloma]. (United States)

    Okamura, Ikue; Ikeda, Takashi; Sato, Ken; Kimura, Fumihiko


    Thalidomide is highly effective against multiple myeloma, but some patients must discontinue this medication due to adverse effects. We present herein an instructive case report on thalidomide-associated hypothyroidism in a patient with multiple myeloma. Thyroid hormone replacement therapy allowed us to restart administration of thalidomide, a potentially life-saving therapy. Known adverse effects of thalidomide, such as lethargy, constipation, and bradycardia, are potential symptoms of hypothyroidism, but we tend to overlook drug-associated hypothyroidism. Our case highlights the importance of routinely testing thyroid function in patients receiving thalidomide therapy.

  13. A rare case of life-threatening penetrating oropharyngeal trauma caused by toothbrush in a child

    Directory of Open Access Journals (Sweden)

    Sagar S


    Full Text Available We present a case of 10year-old boy with oropharyngeal injury caused by a toothbrush which penetrated the parapharyngeal space. Initial examination revealed broken end of the toothbrush in oral cavity with the head of the toothbrush having bristles, beyond the soft palate. Tongue and palate were lacerated and there were blood and oral secretions in the oral cavity. Patient was having bradycardia. Computed tomography (CT scan showed the toothbrush head near the carotid artery, the carotid being laterally displaced. The foreign body was surgically removed without any intraoperative or postoperative complications.

  14. Asystole Following Profound Vagal Stimulation During Hepatectomy

    Directory of Open Access Journals (Sweden)

    Preeta John


    Full Text Available Asystole in a non laparoscopic upper abdominal surgery following intense vagal stimulation is a rare event. This case report highlights the need for awareness of such a complication when a thoracic epidural anaesthetic has been given in addition to a general anaesthetic for an upper abdominal procedure. A combined thoracic epidural and general anaesthetic was given. The anterior abdominal wall was retracted forty minutes after administration of the epidural bolus. This maneuver resulted in a profound vagal response with bradycardia and asystole. The patient was resuscitated successfully with a cardiac massage, atropine and adrenaline and the surgery was resumed. Surgery lasted eleven hours and was uneventful.

  15. Inadvertent intrathecal injection of large dose magnesium sulfate

    Directory of Open Access Journals (Sweden)

    Atabak Najafi


    Full Text Available The case is a 35-year-old man who underwent spinal anesthesia for emergency strangulated inguinal hernia repair. About five minutes after 3 ml intrathecal drug injection, the patient suffered respiratory distress, bradycardia, hypotension and loss of consciousness. The patient was rapidly intubated and crystalloid infusion and epinephrine drip were established. Thereafter, he was admitted in intensive care unit. Search for the cause revealed us that 3 ml of magnesium sulfate (50% was injected mistakenly for spinal anesthesia. Two days later, he was extubated and on the fifth day, he was discharged from the hospital without an obvious evidence of complication.

  16. The Ace of Spades: Reverse Takotsubo Cardiomyopathy in the Context of Angiographic Embolization of Recurrent Metastatic Serotonin-Positive Neuroendocrine Tumour of the Pancreas

    Directory of Open Access Journals (Sweden)

    Ian A. Mazzetti


    Full Text Available A 62-year-old woman undergoing embolization of recurrent neuroendocrine tumor, positive for serotonin, developed chest pain and bradycardia with lateral ST-segment depression. Cardiac biomarkers were elevated, and echocardiography revealed akinesis of all basal segments with a normally contracting apex. The absence of flow-limiting coronary disease on angiography confirmed the presence of reverse Takotsubo cardiomyopathy. After optimal medical therapy for six weeks, left ventricular function returned to normal. Takotsubo cardiomyopathy has been described across a wide variety of hyperadrenergic states; the description of the reverse-type Takotsubo cardiomyopathy in the setting of embolization of recurrent neuroendocrine with serotonergic positivity tumour is novel.

  17. Automatic zebrafish heartbeat detection and analysis for zebrafish embryos. (United States)

    Pylatiuk, Christian; Sanchez, Daniela; Mikut, Ralf; Alshut, Rüdiger; Reischl, Markus; Hirth, Sofia; Rottbauer, Wolfgang; Just, Steffen


    A fully automatic detection and analysis method of heartbeats in videos of nonfixed and nonanesthetized zebrafish embryos is presented. This method reduces the manual workload and time needed for preparation and imaging of the zebrafish embryos, as well as for evaluating heartbeat parameters such as frequency, beat-to-beat intervals, and arrhythmicity. The method is validated by a comparison of the results from automatic and manual detection of the heart rates of wild-type zebrafish embryos 36-120 h postfertilization and of embryonic hearts with bradycardia and pauses in the cardiac contraction.


    Directory of Open Access Journals (Sweden)



    Full Text Available BACKGROUND A study of 50 cases of Traumatic Intracerebral Haematomas was carried out to study the factors affecting management and prognosis. Incidence of Intracerebral Haematomas was more than other Intracranial Haematomas. Young male adults were affected most. Vehicular accident was the commonest mode of injury. Computed tomography was the definitive investigation. Hypertension, bradycardia and associated convulsions carried bad prognosis. Glasgow Coma Scoring was a good indicator of outcome. Commonest site was the Temporal Lobe, Multiple Haematomas and Haematomas involving Brainstem and Basal-Ganglia carried poor prognosis. Mortality was 61.53% and 33.3% in operated and non-operated groups respectively. Most small Haematomas (25 mm surgically

  19. Propafenone hepatotoxicity: Report of a new case and review of the literature

    Directory of Open Access Journals (Sweden)

    Lara B Younan


    Full Text Available Propafenone is a class Ic antiarrhythmic drug. It is a beta-adrenergic blocker that causes bradycardia and bronchospasm. It is metabolized primarily in the liver. Its bioavailability and plasma concentration differ among patients under long-term therapy. They are genetically determined by the hepatic cytochrome P-450 2D6. Hepatic toxicity is highly uncommon. To date, only eight patients were reported in the reviewed world literature. In this article, one new case will be reported emphasizing the importance of medication history taking in patients presenting with new-onset liver enzymes abnormalities.

  20. Effects of Shensong Yangxin capsule on pacemaker channels encoded by human HCN4 gene

    Institute of Scientific and Technical Information of China (English)

    SUN Li-ping; LI Ning; WU Yi-ling; PU Jie-lin


    @@ Shensong Yangxin (SSYX) is one of the compound recipes of Chinese materia medica including 12ingredients such as Panax ginseng, dwarf lilyturf tuber,nardostachys root, etc. Small-scale randomized multi-centre clinical trials suggested that SSYX reduced the number of ventricular extrasystoles in patients with or without structural heart disease.1 Besides excellent antiarrhythmic efficacy,2 SSYX also improved bradycardia in some patients, which was evidenced by animal studies3 as well. However, the antiarrhythmic mechanisms of SSYX have not been fully understood.Our previous studies have explored effect of SSYX on many channels except hyperpolarization-activated cation channel encoded by human hHCN4 gene.4

  1. Adult human metapneumonovirus (hMPV) pneumonia mimicking Legionnaire's disease. (United States)

    Cunha, Burke A; Irshad, Nadia; Connolly, James J


    In adults hospitalized with viral pneumonias the main differential diagnostic consideration is influenza pneumonia. The respiratory viruses causing viral influenza like illnesses (ILIs), e.g., RSV may closely resemble influenza. Rarely, extrapulmonary findings of some ILIs may resemble Legionnaire's disease (LD), e.g., adenovirus, human parainfluenza virus (HPIV-3). We present a most unusual case of human metapneumonovirus pneumonia (hMPV) with some characteristic extrapulmonary findings characteristic of LD, e.g., relative bradycardia, as well as mildly elevated serum transaminases and hyphosphatemia. We believe this is the first reported case of hMPV pneumonia in a hospitalized adult that had some features of LD.

  2. Ultrasound findings in fetal congenital heart block associated with maternal anti-Ro/SSA and Anti-La/SSB antibodies. (United States)

    Lai, Jasmine; Clark, Toshi J; Tan, Justin H; Delaney, Shani; Jolley, Jennifer A


    We present the sonographic features of a second-trimester fetus diagnosed with a bradyarrhythmia at 19 weeks' gestation. The mother carried a diagnosis of Sjögren syndrome, including the presence of SSA and SSB antibodies. Ultrasound M-mode and fetal echocardiogram revealed the etiology of the bradycardia to be a complete fetal congenital heart block, likely due to transplacental passage of autoimmune anti-Ro/SSA and anti-La/SSB antibodies. Consequential to the congenital heart block, the fetus developed hydrops fetalis at 21 weeks' gestational age. We discuss the 2 major etiologies of congenital heart block and the implications in subsequent pregnancies.

  3. Prolonged sinoatrial block in an infant with respiratory syncytial viral bronchiolitis. (United States)

    Haddad, Wajed; Agoudemous, Melissa; Basnet, Sangita


    Complete heart block in children admitted to the pediatric intensive care unit with respiratory syncytial viral (RSV) infections has been described. This report describes a prolonged sinoatrial block exceeding 4 s in an infant with RSV, which, to the authors' knowledge, is the longest such event described in the published literature. This block was followed by shorter episodes within the next 24 h. An extensive workup showed no other known cause of bradycardia or sinoatrial block. The infant was discharged home with 48 h Holter monitoring, which was normal. At this writing, the infant has remained asymptomatic since discharge. Respiratory syncytial viral infections may cause prolonged sinoatrial block in an otherwise healthy child.

  4. Shaping our future: animal health in a global trading environment

    Directory of Open Access Journals (Sweden)

    More Simon J


    Full Text Available Abstract In this study, the clinical findings and results of haematological and biochemical analyses of 26 cattle with botulism were evaluated. The most important clinical signs in the affected cattle included: decreased appetite, ataxia, difficulty to rise, loss of tongue tone, salivation and bradycardia. A definitive diagnosis of botulism was based on demonstration of the preformed toxin in ruminal and intestinal contents and feed materials including poultry litter, by mouse inoculation test. This study is the first confirmation, by direct toxin isolation, of Clostridium botulinum type C and Clostridium botulinum type D in cattle, in Turkey.

  5. Immunochromatographic purification of a nematocyst toxin from the cnidarian Chironex fleckeri (sea wasp). (United States)

    Olson, C E; Pockl, E E; Calton, G J; Burnett, J W


    A cardiotoxin from "milked venom" of the sea wasp (Chironex fleckeri) was purified by immunochromatography on an immobilized mouse monoclonal anti-Portuguese man-o'war (Physalia physalis) venom antibody column. The 20,000 molecular weight toxin caused bradycardia followed by cell lysis when applied to cultured chick embryonic cardiocytes at concentrations higher than 1.7 micrograms protein per ml and was lethal to mice at 0.04 micrograms protein per g. The toxin affected ion permeability in lipid bilayer membranes by forming monovalent cation channels.

  6. Plain film and CT observations in prostaglandin-induced bone changes

    Energy Technology Data Exchange (ETDEWEB)

    Matzinger, M.A.; Briggs, V.A.; Dunlap, H.J.; Udjus, K.; Martin, D.J.; McDonald, P. (Children' s Hospital of Eastern Ontario, Ottawa, ON (Canada). Dept. of Radiology)


    Prostaglandin E[sub 1] intravenous infusion is used in infants with ductal-dependent cogenital heart disease to maintain ductal patency and prolong life until palliative or corrective surgery is feasible. Complications of prostaglandin administration include fever, diarrhoea, hypotension, apnoea, bradycardia, pseudowidening of the cranial sutures, underossification of the calvarial bones, periostitis, and skin edema. This paper presents dramatic plain radiographic features of prostaglandin-induced bone disease, inlcuding periosteal proliferation and the unusual bone-within-bone apperance, and provides the previously unpublished CT correlation. (orig.).

  7. Cardiac arrest after anesthetic management in a patient with hereditary sensory autonomic neuropathy type IV

    Directory of Open Access Journals (Sweden)

    Ergül Yakup


    Full Text Available Hereditary sensory autonomic neuropathy type IV is a rare disorder with an autosomal recessive transmission and characterized by self-mutilation due to a lack in pain and heat sensation. Recurrent hyperpyrexia and anhydrosis are seen in patients as a result of a lack of sweat gland innervation. Self-mutilation and insensitivity to pain result in orthopedic complications and patients undergone recurrent surgical interventions with anesthesia. However, these patients are prone to perioperative complications such as hyperthermia, hypothermia, and cardiac complications like bradycardia and hypotension. We report a 5-year-old boy with hereditary sensory autonomic neuropathy type IV, developing hyperpyrexia and cardiac arrest after anesthesia.

  8. Relief of compromised translocated right coronary artery blood flow by clockwise rotation of the heart in a Jatene procedure. (United States)

    Kan, Chung-Dann; Roan, Jun-Neng; Wu, Jing-Ming; Yang, Yu-Jen


    A 1.9-kg premature boy with transposition of the great arteries, ventricular septal defect, and patent ductus arteriosus received a Jatene procedure at 16 days of age. His coronary artery pattern was type A. His arteries were harvested and translocated to appropriate holes in the sinus portion of his neoaorta. Partial obstruction due to torsion of the translocated right coronary artery was suspected, because the right ventricle turned pink in color to blue and bradycardia developed when cardiopulmonary bypass support was weaned. This was relieved by clockwise rotation of the heart, and the patient recovered well. Follow-up echocardiography 6 months later revealed good biventricular function.

  9. Efficacy of atropine combined with paroxetine in vagus nerve excitatory panic disorder

    Directory of Open Access Journals (Sweden)

    Du N


    Full Text Available Na Du, Xue-Li Sun Department of Psychiatry, West China Hospital, Sichuan University, Chengdu, People’s Republic of China Abstract: Panic disorder is often associated with the autonomic nervous system pattern – sympathetic activation and parasympathetic (vagal withdrawal. However, we present one special case here to show a totally reversed pathogenesis – vagal activation occupying the leading role, which requires atropine to cure the patient’s symptoms. Through this report, it is reasonably proven that panic disorder may be a heterogeneous condition, whose mechanism might be the imbalance between the sympathetic and parasympathetic tone. Keywords: panic disorder, vagal activation, bradycardia, atropine

  10. Central and Peripheral GABA(A) Receptor Regulation of the Heart Rate Depends on the Conscious State of the Animal

    DEFF Research Database (Denmark)

    Bentzen, Bo Hjorth; Grunnet, Morten


    Intuitively one might expect that activation of GABAergic inhibitory neurons results in bradycardia. In conscious animals the opposite effect is however observed. GABAergic neurons in nucleus ambiguus hold the ability to control the activity of the parasympathetic vagus nerve that innervates...... the heart. Upon GABA activation the vagus nerve will be inhibited leaving less parasympathetic impact on the heart. The picture is however blurred in the presence of anaesthesia where both the concentration and type of anaesthetics can result in different effects on the cardiovascular system. This paper...

  11. Symptomatic sick sinus syndrome requiring permanent pacemaker implantation in a patient uwith mirror image dextrocardia with situs inversus and infertility. (United States)

    Kahali, Dhiman; Mandal, Saroj; Mandal, Debasmita; Ghose, Arijit; Kanjilal, Souvik


    Situs inversus with dextrocardia is a congenital condition in which the heart is a mirror image of the anatomically normal heart on the right side. A patient presented with the sick sinus syndrome accompanying mirror image dextrocardia which was associated with double superior vena cava and a left sided inferior vena cava A permanent transvenous demand pacemaker was inserted because of repeated episodes of dizziness and a single episode of syncope with ECG showing bradycardia with junctional escape rhythm. Precise knowledge of the venous system and the location of the apex of the right ventricle were necessary prior to permanent pacemaker implantation. Without such knowledge pacing may be technically challenging.

  12. Detection of the mutation may guide treatment of heart and muscle in Duchenne muscular dystrophy

    Directory of Open Access Journals (Sweden)

    Finsterer J


    Full Text Available Josef Finsterer,1 Sinda Zarrouk-Mahjoub21Krankenanstalt Rudolfstiftung, Vienna, Austria; 2Genomics Platform, Pasteur Institute of Tunis, Tunis, Tunisia We read with great interest the article, by Kono et al, about a 32-year-old male with Duchenne muscular dystrophy (DMD, who was admitted for dilated cardiomyopathy manifesting as heart failure, left bundle branch block, Mobitz-II block, bradycardia, and arterial hypotension. He profited from implantation of a cardiac resynchronization therapy-D system with a defibrillator and beta-blocker treatment. View original article by Kono et al.  

  13. [Pacemaker implantation in dogs: results of the last 30 years]. (United States)

    François, L; Chetboul, V; Nicolle, A; Carlos, C; Borenstein, N; Pouchelon, J L


    Pacemaker implantation in veterinary practice is still not well known and remains uncommon. However, this technique is the only possible way to cure animals suffering from symptomatic bradycardia whose state does not improve with a medical treatment. In most cases, the use of pacemakers in veterinary medicine leads to the disappearance of the clinical and electrocardiographic signs. This retrospective study concerning the last 30 years draws up an evaluation of the improvements, advantages and drawbacks of this method. Moreover, this study allows the understanding of the evolution of pacemakers' use in veterinary cardiology.


    Directory of Open Access Journals (Sweden)

    R. I. Striuk


    Full Text Available Highly selective β-adrenoblockers (β-AB are used in pregnant women with cardiovascular diseases (arterial hypertension, arrhythmia, Marfan syndrome, hypertrophic cardiomyopathy. β-AB fall into the category C according to safety classification of Food and Drug Administration (US FDA. Their prescription in different clinical situations meets the principle of "risk–benefit". Fetus and newborn status should be monitored because β-AB can cause bradycardia, hypoglycemia, apnea and metabolic disorders. The risk of these side effects is extremely low, while β-AB clinical efficacy is high.

  15. [Neurogenic shock]. (United States)

    Meister, Rafael; Pasquier, Mathieu; Clerc, David; Carron, Pierre-Nicolas


    The neurogenic shock is a common complication of spinal cord injury, especially when localized at the cervical level. Characterized by a vasoplegia (hypotension) and bradycardia, the neurogenic shock is secondary to the damage of the sympathetic nervous system. The clinical presentation often includes tetraplegia, with or without respiratory failure. Early treatment aims to minimize the occurrence of secondary spinal cord lesions resulting from systemic ischemic injuries. Medical management consists in a standardized ABCDE approach, in order to stabilize vital functions and immobilize the spine. The hospital care includes performing imaging, further measures of neuro-resuscitation, and coordinated surgical assessment and treatment of any other injury.

  16. Medical image of the week: cervical fracture and dislocation

    Directory of Open Access Journals (Sweden)

    Evan Schmitz


    Full Text Available A 25 year old woman was a restrained driver in a rollover motor vehicle accident (MVA and suffered a C5-C6 fracture-dislocation with spinal cord injury (Figure 1. She developed neurogenic stunned myocardium, symptomatic bradycardia and neurogenic shock. Her cardiac ultrasound has been previously presented and can be viewed by clicking here. After developing the adult respiratory distress syndrome and multi-system organ failure she had multiple cardiac arrests and died after 5 days in the intensive care unit.

  17. [Traumatic neurogenic shock]. (United States)

    Maurin, O; de Régloix, S; Caballé, D; Arvis, A-M; Perrochon, J-C; Tourtier, J-P


    Traumatic neurogenic shock is a rare but serious complication of spinal cord injury. It associates bradycardia and hypotension caused by a medullary trauma. It is life-threatening for the patient and it aggravates the neurological deficit. Strict immobilization and a quick assessment of the gravity of cord injury are necessary as soon as prehospital care has begun. Initial treatment requires vasopressors associated with fluid resuscitation. Steroids are not recommended. Early decompression is recommended for incomplete deficit seen in the first 6 hours. We relate the case of secondary spinal shock to a luxation C6/C7 treated in prehospital care.

  18. Endovascular Aneurysm Repair (EVAR) for Infra-renal Abdominal Aortic Aneurysm (AAA) under Local Anaesthesia - Initial Experience in Hospital Kuala Lumpur. (United States)

    Syed, A; Zainal, A A; Hanif, H; Naresh, G


    This is our initial report on the first 4 cases of infra-renal abdominal aortic aneurysm undergoing Endovascular Aneurysm Repair (EVAR) with local anaesthesia, controlled sedation and monitoring by an anaesthetist. All four patients were males with a mean age of 66.7 years. Only one required ICU stay of two days for cardiac monitoring due to bradycardia and transient hypotension post procedure. No mortality or major post operative morbidity was recorded and the mean hospital stay post procedure was 3.5 days (range 2-5 days).

  19. Levosimendan as Treatment Option in Severe Verapamil Intoxication: A Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Mirjam Osthoff


    Levosimendan, an inotropic agent, that enhances myofilament response to calcium, increases myocardial contraction and could therefore be beneficial in verapamil intoxication. Here, we report the case of a 60-year-old patient with clinically severe verapamil poisoning who presented with shock, bradycardia, and sopor. Standard therapy including high-dose inotropes failed to ameliorate the signs of intoxication. But additional therapy with levosimendan led to rapid improvement. Based on this observation, the literature is reviewed focusing on utilization of levosimendan in the treatment of calcium channel blocker overdose. We suggest to consider levosimendan as additional treatment option in patients with cardiovascular shock due to verapamil intoxication that are refractory to standard management.

  20. Cardiac output and vasodilation in the vasovagal response

    DEFF Research Database (Denmark)

    Wieling, Wouter; Jardine, David L; de Lange, Frederik J


    with vagal-induced bradycardia in simple faint. Studies performed by Barcroft and Sharpey-Schafer between 1940 and 1950 used volume-based plethysmography to demonstrate major forearm vasodilation during extreme hypotension and concluded that the main mechanism for hypotension was vasodilation...... of CO using the Fick principle. They demonstrated that CO significantly fell before syncope, and little vasodilation occurred until very late in the vasovagal reaction Thus, since the 1970s, decreasing cardiac output rather than vasodilation has been regarded as the principal mechanism...

  1. Overdose effect of aconite containing Ayurvedic Medicine ('Mahashankha Vati'). (United States)

    Panda, Ashok Kumar; Debnath, Saroj Kumar


    There are chances that the use of larger than recommended dose of Ayurvedic medicines containing aconite can produce drug reactions. Vatsanabha (Aconitum ferox Wall.) is a very well-known ingredient of Ayurvedic formulations and is prescribed as an antipyretic, analgesic, anti-rheumatic, appetizer and digestive. The recommended dose of purified Vatsanabha (A. ferox Wall.) root is 15 mg. We present a case of hypotension and bradycardia due to aconite poisoning caused by overdosing of an Ayurvedic medicine (Mahashankha Vati), which was primarily managed by Ayurvedic treatment.

  2. [Antihypertensive action of Parkia biglobosa+ (Jacq) Benth seeds in the rat]. (United States)

    Assane, M; Baba Moussa, R; Bassene, E; Sere, A


    Hundred white Wistar rats have been used to evaluate the antihypertensive effects of entire seeds and decorticated, fermented seeds of a soudanian plant, Parkia biglobosa. The arterial blood pressure was measured by using bloody method in anesthizied animals. The Pham Huu Chanh method was used to determine type plant's antihypertensive activity. According to the results obtained, in both preparations, adequate doses decrease arterial blood pressure, diastolic more than systolic, but the effect of fermented seeds was more important than the entire seeds. In the two cases, the decrease in blood pressure is greated in hypertensive than in normotensive subjects, and the hypotension induced was well correlated with a bradycardia.

  3. [Heart disease in schizophrenia]. (United States)

    Wobrock, T; Sittinger, H; Kindermann, M; Behrendt, B


    A 63-year-old male patient diagnosed with chronic schizophrenia and characterized by formal disorders of thought with neologism and paranoid ideation, especially grandiose delusions and feelings of being influenced by radiation, is presented. At admission to psychiatric hospital, the patient reported attacks of weakness and dizziness, which he attributed to his feelings of alien influence. The diagnosis of cardiac disease with severe bradycardia could already be established by basic physical examination. Further diagnostic procedures (e.g., ECG) revealed symptomatic atrioventricular conduction defects (atrioventricular block III). After implantation of a cardiac pacemaker, the somatic symptoms vanished and the patient recovered completely in terms of physical condition.

  4. Cardiovascular inhibition of salusin α within the nucleus tractus solitarii originated from suppressing the activities of presympathetic neurons in the rostral ventrolateral medulla%salusin α在孤束核内的心血管效应可能通过抑制头端延髓腹外侧区前交感神经元活动介导

    Institute of Scientific and Technical Information of China (English)

    李宏宝; 郭雅琼; 鲁彦; 伏晓琳; 刘颖璐; 郑天珍


    Aim Salusin a and salusin β are newly I-dentified bioactive peptides of 28 and 20 amino acid, respectively, which are reported to widely distribute in hematopoietic system, endocrine system and the central nervous system ( CNS ). They are responsible for causing hypotension, bradycardia and mitogenic activities. The cardiovascular functions of salusin a in the nucleus tractus solitarii ( NTS ) are not fully defined. The present study is to comparatively determine the cardiovascular functions of salusin a into the NTS in anesthetized rats. Methods Ninety-four anesthetic male SD rats were employed in present study. The dose-dependant responses of blood pressure and heart rate of salusin a ( 0. 04 ~ 4 pmol ) in the NTS were determined by bilateral or unilateral microinjection salusin a or artificial cerebrospinal fluid ( aCSF ) into the NTS in 50 rats. In 33 rats, aCSF, KYN, bilateral vagotomy or aCSF/ muscimol in RVLM were prior applied before salusin a ( 4 pmol ) was microinjected. The arterial baroreflex( ABR ) functions of rats of pre-post injection of salusin a into the NTS were defined in 11 rats. Results Bilateral or unilateral microinjection of salusin a into the NTS produced dose-dependent hypotension and bradycardia. Bilateral microinjection of salusin a did not alter baroreflex sensitivity functions. Prior application of KYN( 1 nmol ) or bilateral vagotomy into the NTS did not alter the hypotension and bradycardia induced by intra-NTS salusin a( P >0. 05 ). But pretreatment with muscimol ( 5 pmol )within the RVLM almost completely abolished the hypotension and bradycardia evoked by intra-NTS salusin a( P 0.05).RVLM预先注射muscimol (5 pmol)能有效阻断salusin α(4 pmol)在孤束核产生的降低血压、减缓心率的效应(P<0.05).结论 NTS注射salusin α产生的降低血压、减缓心率的效应可能通过激动RVLM内GABA受体,抑制前交感神经元兴奋性发挥作用.

  5. Naloxone induces multiple effects on aversive Pavlovian conditioning in rabbits. (United States)

    Hernández, L L; Powell, D A


    A series of experiments examined the effects of intravenous naloxone treatment on aversive Pavlovian conditioning of eye-blink and heart rate responses, and related unconditioned behaviors, in rabbits. Naloxone treatment before testing attenuated bradycardiac orienting responses to tones used as conditioning stimuli. Naloxone also attenuated conditioned bradycardia when administered either before or after training sessions, but it potentiated conditioned bradycardia during extinction of discriminative conditioning. Naloxone did not influence acquisition or extinction of discriminative eye-blink conditioning or somatic or cardiac responses to shocks used as unconditioned stimuli, but it did decrease locomotor activity. Naloxone treatment immediately after training sessions facilitated acquisition of eye-blink responses. It was concluded that naloxone influences aversive Pavlovian conditioning in more than one way: (a) During training, it appears to alter reception and processing of signals but does not affect subsequent development of somatic responses to the Pavlovian conditioning contingency. (b) After training sessions, naloxone apparently affects consolidation of both somatic and autonomic conditioning. (c) Naloxone also appears to delay extinction of Pavlovian conditioning; this effect may similarly involve changes in a stimulus-processing mechanism or in memory functions, but it apparently does not involve changes in somatomotor responsitivity.

  6. Blood pressure control with selective vagal nerve stimulation and minimal side effects (United States)

    Plachta, Dennis T. T.; Gierthmuehlen, Mortimer; Cota, Oscar; Espinosa, Nayeli; Boeser, Fabian; Herrera, Taliana C.; Stieglitz, Thomas; Zentner, Joseph


    Objective. Hypertension is the largest threat to patient health and a burden to health care systems. Despite various options, 30% of patients do not respond sufficiently to medical treatment. Mechanoreceptors in the aortic arch relay blood pressure (BP) levels through vagal nerve (VN) fibers to the brainstem and trigger the baroreflex, lowering the BP. Selective electrical stimulation of these nerve fibers reduced BP in rats. However, there is no technique described to localize and stimulate these fibers inside the VN without inadvertent stimulation of non-baroreceptive fibers causing side effects like bradycardia and bradypnea. Approach. We present a novel method for selective VN stimulation to reduce BP without the aforementioned side effects. Baroreceptor compound activity of rat VN (n = 5) was localized using a multichannel cuff electrode, true tripolar recording and a coherent averaging algorithm triggered by BP or electrocardiogram. Main results. Tripolar stimulation over electrodes near the barofibers reduced the BP without triggering significant bradycardia and bradypnea. The BP drop was adjusted to 60% of the initial value by varying the stimulation pulse width and duration, and lasted up to five times longer than the stimulation. Significance. The presented method is robust to impedance changes, independent of the electrode's relative position, does not compromise the nerve and can run on implantable, ultra-low power signal processors.

  7. Sudden Infant Death Syndrome – Role of Trigeminocardiac Reflex: A Review (United States)

    Singh, Gyaninder Pal; Chowdhury, Tumul; Bindu, Barkha; Schaller, Bernhard


    Sudden infant death syndrome (SIDS) is an unexplained death in infants, which usually occurs during sleep. The cause of SIDS remains unknown and multifactorial. In this regard, the diving reflex (DR), a peripheral subtype of trigeminocardiac reflex (TCR), is also hypothesized as one of the possible mechanisms for this condition. The TCR is a well-established neurogenic reflex that manifests as bradycardia, hypotension, apnea, and gastric hypermotility. The TCR shares many similarities with the DR, which is a significant physiological adaptation to withstand hypoxia during apnea in many animal species including humans in clinical manifestation and mechanism of action. The DR is characterized by breath holding (apnea), bradycardia, and vasoconstriction, leading to increase in blood pressure. Several studies have described congenital anomalies of autonomic nervous system in the pathogenesis of SIDS such as hypoplasia, delayed neuronal maturation, or decreased neuronal density of arcuate nucleus, hypoplasia, and neuronal immaturity of the hypoglossal nucleus. The abnormalities of autonomic nervous system in SIDS may explain the role of TCR in this syndrome involving sympathetic and parasympathetic nervous system. We reviewed the available literature to identify the role of TCR in the etiopathogenesis of SIDS and the pathways and cellular mechanism involved in it. This synthesis will help to update our knowledge and improve our understanding about this mysterious, yet common condition and will open the door for further research in this field. PMID:27994573

  8. Dual chamber pacemaker in the treatment of paroxysmal atrial fibrillation

    Directory of Open Access Journals (Sweden)

    Rađen Goran


    Full Text Available Background. Atrial fibrillation is the most frequent cardiac dysrhythmia. The aim of this study was to show the role and the efficacy of a dual chamber pacemaker with the algorithm of atrial dynamic overdrive, in the suppression of paroxysmal atrial fibrillation. Case report. A woman with a classical bradycardia-tachycardia syndrome, and frequent attacks of atrial fibrillation, underwent the implantation of a single chamber permanent pacemaker (VVI. Pacemaker successfully treated the episodes of symptomatic bradycardia, but the patient had frequent attacks of atrial fibrillation, despite the use of different antiarrhythmic drugs, which she did not tolerate well. The decision was made to reimplant a permanent dual chamber pacemaker with the algorithm of atrial dynamic overdrive. The pacemaker was programmed to the basic rate of 75/min, while rate at rest was 55/min. In addition, sotalol was administered. After three months, the patient became asymptomatic with only 4 short − term episodes of atrial fibrillation, and a high level of atrial pacing (99%. Conclusion. In selected patients with bradycardia−tachycardia syndrome, atrial-based pacing seemed to be very effective in reducing the incidence of paroxysmal atrial fibrillation.

  9. [Influence of beta block and autonomic nerve block on the recovery time of the sinus node in sick sinus syndrome and carotid sinus syndrome]. (United States)

    Brignole, M; Sartore, B; Barra, M; Menozzi, C; Monducci, I; Bertulla, A


    In order to evaluate the relative role of the automatic nervus system and of the intrinsic electrophysiologic properties on the sinus node function, we measured the corrected sinus node recovery time before and after autonomic nervous system blockade in 24 patients. Fourteen had a sick sinus syndrome, five had a carotid sinus syncope, two had syncope of unknown origin associated with bradycardia. Beta blockade was obtained by infusing metoprolol intravenously at a dosage of 0.2 mg/kg; complete automatic blockade was achieved by further i.v. administration of atropine at a dosage of 0.04 mg/kg. After beta blockade, the corrected sinus node recovery time increased in patients with sick sinus syndrome and intrinsic slow heart rate, whereas it decreased in patients with carotid sinus syncope or with syncope and bradycardia. In patients with sick sinus syndrome and normal intrinsic heart rate the response was variable. A positive direct correlation was found between the changes of the corrected sinus node recovery time induced by beta blockade and those induced by autonomic blockade; that is, both either prolonged or shortened the corrected sinus node recovery time. The changes of the corrected sinus node recovery time after beta blockade alone were inversely correlated with the intrinsic heart rate. We conclude that patients with intrinsic depression of the sinus node have an increased sympathetic tone.

  10. Cardiovascular Effects of the Essential Oil of Croton argyrophylloides in Normotensive Rats: Role of the Autonomic Nervous System (United States)

    Alves-Santos, Thayane Rebeca; de Siqueira, Rodrigo José Bezerra; Duarte, Gloria Pinto


    Cardiovascular effects of the essential oil of Croton argyrophylloides Muell. Arg. (EOCA) were investigated in normotensive rats. In saline-pretreated anesthetized or conscious rats, intravenous (i.v.) injection of the EOCA induced dose-dependent hypotension. Dose-dependent tachycardia was observed only in conscious rats. In anesthetized rats, cervical bivagotomy failed to enhance EOCA-induced hypotension but unmasked significant bradycardia. In conscious rats, i.v. pretreatment with methylatropine, but not with atenolol or L-NAME, reduced both hypotensive and tachycardiac responses to EOCA. However, hexamethonium pretreatment reverted the EOCA-induced tachycardia into significant bradycardia without affecting the hypotension. In aortic ring preparations precontracted with phenylephrine, EOCA induced a concentration-dependent relaxation that was significantly reduced by vascular endothelium removal and pretreatment with atropine, indomethacin, or glibenclamide but remained unaffected by pretreatment with L-NAME or TEA. It is concluded that i.v. treatment with EOAC decreased blood pressure probably through an active vascular relaxation rather than withdrawal of sympathetic tone. Muscarinic receptor stimulation, liberation of the endothelium-derived prostacyclin, and opening KATP channels are partially involved in the aortic relaxation induced by EOCA and in turn in the mediation of EOCA-induced hypotension. EOCA-induced tachycardia in conscious rats appears to be mediated reflexly through inhibition of vagal drive to the heart. PMID:27956919

  11. Assessment of cardiotoxicity and effects of malathion on the early development of zebrafish (Danio rerio) using computer vision for heart rate quantification. (United States)

    Simoneschi, Daniele; Simoneschi, Francesco; Todd, Nancy E


    Malathion, a common organophosphate insecticide, is a proven acetylcholinesterase inhibitor and is the most applied organophosphate insecticide in the United States. The use of zebrafish as a model to study the effects of pesticides on development is an innovative approach yielding relevant implications for determining the potential toxic effects of these pesticides on humans. In this study, a simple noninvasive technique was developed to investigate the cardiotoxicity of malathion on Danio rerio embryos, and to detect and quantify its effect on heart rate. Videos were recorded under a stereomicroscope and examined with our custom-made software (FishBeat) to determine the heart rate of the embryos. The pixel average intensity frequency (PI) of the videos was computed at its maximum probability to indicate the average number of heartbeats per second. Experimental observations successfully demonstrated that this method was able to detect the heart rate of zebrafish embryos as compared with manual stopwatch counting, with no significant difference. Embryos were treated acutely with increasing malathion concentrations (33.3 and 50 μg/mL malathion) at 52, 76, and 96 hpf. Embryos treated with 33.3 μg/mL malathion had significant bradycardia at 52 and 76 hpf, whereas embryos treated with 50 μg/mL malathion presented bradycardia at all hpf. These novel observations confirmed that malathion, acting as an acetylcholinesterase inhibitor, induced heartbeat irregularity in zebrafish embryos.

  12. [Perioperative management of a child with central diabetes insipidus who underwent two surgeries before and after desmopressin administration]. (United States)

    Kiriyama, Keiji; Tachibana, Kazuya; Nishimura, Nobuyuki; Takeuchi, Muneyuki; Kinouchi, Keiko


    A 14-year-old girl weighing 32 kg was diagnosed with suprasellar tumor causing hydrocephalus, hypothyroidism, adrenal dysfunction and central diabetes insipidus. She was treated with levothyroxine and hydrocortisone and urged to take fluid to replace urine. She was scheduled to undergo ventricular drainage to relieve hydrocephalus prior to tumor resection. For the first surgery, desmopressin was not started and urine output reached 4,000 to 6,000 ml x day(-1), urine osmolality 64 mOsm x l(-1) and urine specific gravity 1.002. Anesthesia was induced with sevoflurane and maintained with propofol and remifentanil. Maintenance fluid was with acetated Ringer's solution and urine loss was replaced with 5% dextrose. Bradycardia and hypotension occurred after intubation, which was treated with volume load. Infusion volume was 750 ml and urine output was 1100 ml during 133 min of anesthesia. Postoperative day 1 nasal desmopressin was started. Ten days later, partial tumor resection was performed. Anesthesia was induced with propofol and fentanyl and maintained with sevoflurane and remifentanil. Infusion volume was 610 ml, urine output 380 ml, and blood loss 151 ml during 344 min of anesthesia. Hemodynamic parameters were stable throughout the procedure. Pathology of the tumor was revealed to be germinoma. Bradycardia and hypotension experienced during the first surgery was suspected to be caused by preoperative hypovolemia brought by polyuria. Desmopressin was proved to be effective to treat excessive urine output and to maintain good perioperative water balance.

  13. [Effect of tranquilizers (diazepam and chlordiazepoxide) on the blood supply and activity of the heart]. (United States)

    Chichikanov, G G


    The effect of diazepam (0.15 and 0.5 mg/kg) and chlordiazepoxide (1.0 and 2.0 mg/kg) on the blood supply and cardiac action were investigated in experiments on cats anesthetized with urethan and chlorasol. Both these compounds were found to lower the vascular resistance to the blood flow, to bring down the coronary circulation rate and the oxygen intake of the heart. The preparations exert a marked influence on the work of the heart and the state of hemodynamics. Diazepam causes the development of an appreciable hypertension, bradycardia and reduces the cardiac ejection. Chlordiazepoxide produces a less pronounced fall of the arterial pressure, bradycardia and reduced the cardiac ejection. Unlike chlordiazepoxide diapezam reduces the contractibility of the myocardium, this being manifested in lessening the maximum acceleration of the blood flow in the aorta and in an increase of the systolic contraction time. Inhibition of the myocardium contractility occurring under the influence of diazepam may, to a certain degree, explain more pronounced hypotension observable on administration of this preparation.

  14. Dynamic resistance training decreases sympathetic tone in hypertensive ovariectomized rats

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    Shimojo, G.L.; Palma, R.K.; Brito, J.O.; Sanches, I.C. [Laboratório de Fisiologia Translacional, Programa de Ciências da Reabilitação, Universidade Nove de Julho, São Paulo, SP (Brazil); Irigoyen, M.C. [Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); De Angelis, K. [Laboratório de Fisiologia Translacional, Programa de Ciências da Reabilitação, Universidade Nove de Julho, São Paulo, SP (Brazil)


    The aim of this study was to investigate the effects of resistance exercise training on hemodynamics and cardiac autonomic control in ovariectomized spontaneously hypertensive rats. Female rats were divided into 4 groups: sedentary control (SC), sedentary hypertensive (SH), sedentary hypertensive ovariectomized (SHO), and resistance-trained hypertensive ovariectomized (RTHO). Resistance exercise training was performed on a vertical ladder (5 days/week, 8 weeks) at 40-60% maximal load. Direct arterial pressure was recorded. Vagal and sympathetic tones were measured by heart rate (HR) responses to methylatropine (3 mg/kg, iv) and propranolol (4 mg/kg, iv). Ovariectomy resulted in additional increases in blood pressure in hypertensive rats and was associated with decreased vagal tone. Resistance exercise trained rats had lower mean arterial pressure than untrained rats (RTHO: 159±2.2 vs SHO: 177±3.4 mmHg), as well as resting bradycardia (RTHO: 332±9.0 vs SHO: 356±5 bpm). Sympathetic tone was also lower in the trained group. Moreover, sympathetic tone was positively correlated with resting HR (r=0.7, P<0.05). The additional arterial pressure increase in hypertensive rats caused by ovarian hormone deprivation was attenuated by moderate-intensity dynamic resistance training. This benefit may be associated with resting bradycardia and reduced cardiac sympathetic tone after training, which suggests potential benefits of resistance exercise for the management of hypertension after ovarian hormone deprivation.

  15. Characterization of Cardiorespiratory Events following Gastroesophageal Reflux (GER) in Preterm Infants (United States)

    Di Fiore, Juliann; Arko, Marina; Herynk, Brad; Martin, Richard; Hibbs, Anna Maria


    Objective To characterize cardiorespiratory events in preterm infants following both acid and non-acid GER as detected by pH and multiple intraluminal impedance (MII). Study Design Twelve hour overnight studies were performed in 71 preterm infants (gestational age 29.4±3.0 wks, birth weight 1319±496 gm). Apnea ≥10 seconds in duration, bradycardia ≤80 bpm and oxygen desaturation ≤85% that occurred within 30 seconds after the initiation of GER were classified as associated with GER. Result 12,957 cardiorespiratory events and 4164 GER episodes were documented. Less than 3% of all cardiorespiratory events were preceded by GER constituting 3.4% of apnea, 2.8% of oxygen desaturation and 2.9% of bradycardia events. GER did not prolong cardiorespiratory event duration or increase severity. In contrast, GER was associated with a shorter duration of oxygen desaturation events (7.8±4.6 vs 6.3±5.6 sec, p<.05). Conclusion GER is rarely associated with cardiorespiratory events, and has no detrimental effect on cardiorespiratory event duration or severity. PMID:20220760

  16. The anti-malarial drug Mefloquine disrupts central autonomic and respiratory control in the working heart brainstem preparation of the rat

    Directory of Open Access Journals (Sweden)

    Lall Varinder K


    Full Text Available Abstract Background Mefloquine is an anti-malarial drug that can have neurological side effects. This study examines how mefloquine (MF influences central nervous control of autonomic and respiratory systems using the arterially perfused working heart brainstem preparation (WHBP of the rat. Recordings of nerve activity were made from the thoracic sympathetic chain and phrenic nerve, while heart rate (HR and perfusion pressure were also monitored in the arterially perfused, decerebrate, rat WHBP. MF was added to the perfusate at 1 μM to examine its effects on baseline parameters as well as baroreceptor and chemoreceptor reflexes. Results MF caused a significant, atropine resistant, bradycardia and increased phrenic nerve discharge frequency. Chemoreceptor mediated sympathoexcitation (elicited by addition of 0.1 ml of 0.03% sodium cyanide to the aortic cannula was significantly attenuated by the application of MF to the perfusate. Furthermore MF significantly decreased rate of return to resting HR following chemoreceptor induced bradycardia. An increase in respiratory frequency and attenuated respiratory-related sympathetic nerve discharge during chemoreceptor stimulation was also elicited with MF compared to control. However, MF did not significantly alter baroreceptor reflex sensitivity. Conclusions These studies indicate that in the WHBP, MF causes profound alterations in autonomic and respiratory control. The possibility that these effects may be mediated through actions on connexin 36 containing gap junctions in central neurones controlling sympathetic nervous outflow is discussed.

  17. Large Outbreaks of Ciguatera after Consumption of Brown Marbled Grouper

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    Thomas Y. K. Chan


    Full Text Available Brown marbled grouper (Epinephelus fuscoguttatus is an apex predator from coral reefs of the Indo-Pacific region. All five published case series of ciguatera after consumption of brown marbled grouper were reviewed to characterize the types, severity and chronicity of ciguatera symptoms associated with its consumption. Three of these case series were from large outbreaks affecting over 100–200 subjects who had eaten this reef fish served at banquets. Affected subjects generally developed a combination of gastrointestinal, neurological and, less commonly, cardiovascular symptoms. Gastrointestinal symptoms occurred early and generally subsided in 1–2 days. Some neurological symptoms (e.g., paresthesia of four limbs could last for weeks or months. Sinus bradycardia and hypotension occurred early, but could be severe and prolonged, necessitating the timely use of intravenous fluids, atropine and dopamine. Other cardiovascular and neurological features included atrial ectopics, ventricular ectopics, dyspnea, chest tightness, PR interval >0.2 s, ST segment changes, polymyositis and coma. Concomitant alcohol consumption was associated with a much higher risk of developing bradycardia, hypotension and altered skin sensation. The public should realize that consumption of the high-risk fish (especially the ciguatoxin-rich parts and together with alcohol use and repeated ciguatoxin exposures will result in more severe and chronic illness.

  18. Fingolimod for multiple sclerosis and emerging indications: appropriate patient selection, safety precautions, and special considerations

    Directory of Open Access Journals (Sweden)

    Ayzenberg I


    Full Text Available Ilya Ayzenberg, Robert Hoepner, Ingo Kleiter Department of Neurology, St Josef Hospital, Ruhr University Bochum, Bochum, Germany Abstract: Fingolimod (FTY720, an immunotherapeutic drug targeting the sphingosine-1-phosphate receptor, is a widely used medication for relapsing-remitting multiple sclerosis (MS. Apart from the pivotal Phase III trials demonstrating efficacy against placebo and interferon-β-1a once weekly, sufficient clinical data are now available to assess its real-world efficacy and safety profile. Approved indications of fingolimod differ between countries. This discrepancy, to some extent, reflects the intermediate position of fingolimod in the expanding lineup of MS medications. With individualization of therapy, appropriate patient selection gets more important. We discuss various scenarios for fingolimod use in relapsing-remitting MS and their pitfalls: as first-line therapy, as escalation therapy after failure of previous immunotherapies, and as de-escalation therapy following highly potent immunotherapies. Potential side effects such as bradycardia, infections, macular edema, teratogenicity, and progressive multifocal leukoencephalopathy as well as appropriate safety precautions are outlined. Disease reactivation has been described upon fingolimod cessation; therefore, patients should be closely monitored for MS activity for several months after stopping fingolimod. Finally, we discuss preclinical and clinical data indicating neuroprotective effects of fingolimod, which might open the way to future indications such as stroke, Alzheimer’s disease, and other neurodegenerative disorders. Keywords: immunotherapy, bradycardia, progressive multifocal leukoencephalopathy, neuroprotection, stroke, Alzheimer’s disease 

  19. The Popeye domain containing genes: essential elements in heart rate control. (United States)

    Schindler, Roland F; Poon, Kar Lai; Simrick, Subreena; Brand, Thomas


    The Popeye domain containing (Popdc) gene family displays preferential expression in skeletal muscle and heart. Only recently a significant gain in the understanding of the function of Popdc genes in the heart has been obtained. The Popdc genes encode membrane proteins harboring an evolutionary conserved Popeye domain, which functions as a binding domain for cyclic adenosine monophosphate (cAMP). Popdc proteins interact with the two-pore channel TREK-1 and enhance its current. This protein interaction is modulated by cAMP. Null mutations of members of the Popdc gene family in zebrafish and mouse are associated with severe cardiac arrhythmia phenotypes. While in zebrafish an atrioventricular block was prevalent, in mouse a stress-induced sinus bradycardia was observed, which was due to the presence of sinus pauses. Moreover, the phenotype develops in an age-dependent manner, being absent in the young animal and becoming increasingly severe, as the animals grow older. This phenotype is reminiscent of the sick sinus syndrome (SSS), which affects mostly the elderly and is characterized by the poor ability of the cardiac pacemaker to adapt the heart rate to the physiological demand. While being a prevalent disease, which is responsible for a large fraction of pacemaker implantations in Western countries, SSS is poorly understood at the molecular level. It is therefore expected that the study of the molecular basis of the stress-induced bradycardia in Popdc mice will shed new light on the etiology of pacemaker disease.

  20. Sudden infant death syndrome (SIDS - The role of trigemino-cardiac reflex: A review

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    Gyaninder Pal Singh


    Full Text Available Sudden infant death syndrome (SIDS is an unexplained death in infants that usually occurs during sleep. The cause of SIDS remains unknown and multifactorial. In this regard, the diving reflex (DR, a peripheral subtype of trigeminocardiac reflex (TCR is also hypothesized as one of the possible mechanisms for this condition. The TCR is a well-established neurogenic reflex which manifests as bradycardia, hypotension, apnea, and gastric hyper motility. The TCR shares many similarities with the DR which is a significant physiological adaptation to withstand hypoxia during apnea in many animal species including humans in clinical manifestation and mechanism of action. The DR is characterized by breath-holding (apnea, bradycardia and vasoconstriction leading to rising in blood pressure. Several studies have described congenital anomalies of autonomic nervous system in the pathogenesis of SIDS such as hypoplasia, delayed neuronal maturation or decreased neuronal density of arcuate nucleus, hypoplasia and neuronal immaturity of the hypoglossal nucleus. The abnormalities of autonomic nervous system in SIDS may explain the role of TCR in this syndrome involving sympathetic and parasympathetic nervous system. We reviewed the available literature to identify the role of TCR in the etiopathogenesis of SIDS and the pathways and cellular mechanism involved in it. This synthesis will help to update our knowledge and improve our understanding about this mysterious, yet common condition and will open the door for further research in this field.

  1. Prevalence of electrocardiographic changes in patients with acute aneurysmal subarachnoid hemorrhage and their relationship with outcome

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    Saktheeswaran Mahesh Kumar


    Full Text Available Background: Electrocardiographic (ECG alterations occurring after subarachnoid hemorrhage (SAH have been described frequently, but the prognostic significance of these changes has not been well characterized. Aim and Objectives: To report the prevalence and patterns of ECG alterations in patients with acute aneurysmal SAH and to study the relationship between ECG alterations and the neurological outcome, if any. Materials and Methods: Records of consecutive patients admitted to the neurosurgical intensive care unit of the SCTIMST, Trivandrum between January 1999 and January 2011 with acute aneurysmal SAH were retrospectively analyzed. Results: Of the 321 patients with SAH, 190 (59.2% had abnormal ECGs. Repolarization abnormalities were the most common, with T wave inversion in the anterolateral leads occurring in 155 (48.3% patients. By univariate analysis, female sex, Glasgow Coma Score (GCS at admission of I, ST segment depression or T inversion in anterolateral leads, prolonged corrected QT interval, and sinus bradycardia were associated with increased risk of death. By multivariate analysis, only GCS and WFNS grade independently predicted mortality and none of the ECG changes predicted the same. Presence of tall T waves in anterior leads, T inversion in anterolateral leads, sinus bradycardia, and WFNS grade >1 were independently associated with GCS <15 and poor outcome at discharge. Conclusions: In patients with acute aneurysmal SAH, repolarization abnormalities are the commonest ECG alterations. ECG alterations do not independently predict death, but independently predict poor discharge neurological status.

  2. Safety Profile and Effects of Pulsed Methylprednisolone on Vital Signs in Thyroid Eye Disease

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    Kai-Ling Yong


    Full Text Available Objective. To analyze changes in vital signs (heart rate (HR, systolic (SBP, and diastolic blood pressure (DBP during and after intravenous methylprednisolone (IVMP and any other adverse effects. Methods. Retrospective review of charts of patients who received IVMP as treatment regime for thyroid eye disease. All subjects had vital signs charted during and after infusions. Results. This study included 38 subjects and a total of 242 infusions administered. IVMP resulted in a small but significant percentage drop in mean SBP at 30 min (p<0.001 and 60 min (p=0.03 but no difference at 90 min. There was also small but significant percentage drop in mean DBP and HR (DBP: p<0.001 for 30 min, p=0.001 for 60 min, and p=0.02 for 90 min and HR: p<0.001 for 30 min, 60 min, and 90 min. There were no cumulative effects on change of blood pressure or HR. There were 6 episodes of bradycardia (2.5% and 12 episodes of moderate to severe hypertension (5%. No significant cardiovascular or hepatic toxicity was found. Conclusion. IVMP is relatively safe and efficacious. IVMP demonstrated mild and noncumulative effects on vital signs. Severe hypertension may occur in susceptible individuals such as those with underlying hypertension and uncontrolled thyroid dysfunction, whereas bradycardia may be more likely in those on beta-blockers.

  3. Intrapartum FHR monitoring and neonatal CT brain scan

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    Takahashi, Yoshiki; Ukita, Masahiko; Nakada, Eizo (Kurashiki Central Hospital, Okayama (Japan))


    The effect of fetal distress on the neonatal brain was investigated by neonatal CT brain scan, FHR monitoring and mode of delivery. This study involved 11 cases of full term vertex delivery in which FHR was recorded by fetal direct ECG during the second stage labor. All infants weighed 2,500 g or more. FHR monitoring was evaluated by Hon's classification. Neonatal brain edema was evaluated by cranial CT histgraphic analysis (Nakada's method). 1) Subdural hemorrhage was noted in 6 of 7 infants delivered by vacuum extraction or fundal pressure (Kristeller's method). 2) Intracranial hemorrhage was demonstrated in all of 3 infants with 5-min. Apgar score 7 or less. 3) Two cases with prolonged bradycardia and no variability had intraventricular or intracerebral hemorrhage which resulted in severe central nervous system damage. 4) The degree of neonatal brain edema correlated with 5-min. Apgar score. 5) One case with prolonged bradycardia and no variability resulted in severe neonatal brain edema. Four cases with variable deceleration and increased variability resulted in mild neonatal brain edema. Two cases with late deceleration and decreased variability resulted in no neonatal brain edema.

  4. Cardiac arrhythmias during or after epileptic seizures (United States)

    van der Lende, Marije; Surges, Rainer; Sander, Josemir W; Thijs, Roland D


    Seizure-related cardiac arrhythmias are frequently reported and have been implicated as potential pathomechanisms of Sudden Unexpected Death in Epilepsy (SUDEP). We attempted to identify clinical profiles associated with various (post)ictal cardiac arrhythmias. We conducted a systematic search from the first date available to July 2013 on the combination of two terms: ‘cardiac arrhythmias’ and ‘epilepsy’. The databases searched were PubMed, Embase (OVID version), Web of Science and COCHRANE Library. We attempted to identify all case reports and case series. We identified seven distinct patterns of (post)ictal cardiac arrhythmias: ictal asystole (103 cases), postictal asystole (13 cases), ictal bradycardia (25 cases), ictal atrioventricular (AV)-conduction block (11 cases), postictal AV-conduction block (2 cases), (post)ictal atrial flutter/atrial fibrillation (14 cases) and postictal ventricular fibrillation (3 cases). Ictal asystole had a mean prevalence of 0.318% (95% CI 0.316% to 0.320%) in people with refractory epilepsy who underwent video-EEG monitoring. Ictal asystole, bradycardia and AV-conduction block were self-limiting in all but one of the cases and seen during focal dyscognitive seizures. Seizure onset was mostly temporal (91%) without consistent lateralisation. Postictal arrhythmias were mostly found following convulsive seizures and often associated with (near) SUDEP. The contrasting clinical profiles of ictal and postictal arrhythmias suggest different pathomechanisms. Postictal rather than ictal arrhythmias seem of greater importance to the pathophysiology of SUDEP. PMID:26038597

  5. Suppression of torsades de pointes by atropine. (United States)

    Tan, H L; Wilde, A A; Peters, R J


    A 67 year old woman with a history of chronic atrial fibrillation presented with asthma cardiale. She took no medication and there was no family history of long QT syndrome. She was treated with furosemide, nitroprusside, acenocoumarol, and digoxin. Two days later excessively prolonged RR intervals, which were terminated by escape beats with a right bundle branch block morphology, suggested impending total AV block. There was also severe QT (0.48 s) and QTc (0.56) interval prolongation with bizarre inverted TU waves and multifocal premature ventricular complexes within the U waves. The patient experienced angina pectoris followed by episodes of torsades de pointes, which were interpreted as the result of bradycardia, and the bradycardia as the result of high grade AV block induced by increased vagal tone caused by ischaemia in the presence of digoxin intoxication (serum digoxin was 2.5 micrograms/l). Subsequent atropine infusion sped up the ventricular rate and shortened the QT (0.39) and QTc (0.51) intervals. Digoxin was replaced by metoprolol to control ventricular rate and angina pectoris. Within days, QT and QTc intervals became normal and the U waves disappeared. Neither torsades de pointes nor angina pectoris recurred. Based on a review of the literature, it is suggested that the electrophysiological mechanism of this effect is not only an increase of the heart rate, but also a direct action of muscarinic receptor antagonism on Purkinje cells and ventricular refractoriness.

  6. Rates of oxygen consumption and tolerance of hypoxia and desiccation in Chinese black sleeper (Bostrichthys sinensis) and mudskipper (Boleophthalmus pectinirostris) embryos

    Institute of Scientific and Technical Information of China (English)

    CHEN Shixi; HONG Wanshu; ZHANG Qiyong; WU Renxie; WANG Qiong


    The rates of oxygen consumption, tolerance of hypoxia and desiccation of the Chinese black sleeper (Bostrichthys sinensis) and mudskipper (Boleophthalmus pectinirostris) embryos were investigated. The pattern of oxygen consumption of the Chinese black sleeper embryos was similar to that of the mudskipper ones. The lowest rates of oxygen consumption[(1.65±0.66)nmol/(ind.·h)] of the Chinese black sleeper embryos 16 h after fertilization and the lowest rates of oxygen consumption [(0.79±0.08)nmol/(ind.·h)] of the mudskipper embryos 6 h after fertilization were recorded, respectively. Then the rates of oxygen consumption of these two species embryos increased gradually until hatching [(8.26±1.70)nmol/(ind.·h)in the Chinese black sleeper, (2.69±0.23)nmol/(ind.·h) in mudskipper]. After exposure to hypoxia water (0.16 mg/dm3), bradycardia of the embryos occurred in both the Chinese black sleeper and the mudskipper. However, the Chinese black sleeper embryos survived approximately 45 min longer than the mudskipper ones. After exposure to desiccation at a relative humidity of 58%, bradycardia of the embryos was observed in both the Chinese black sleeper and the mudskipper, and the Chinese black sleeper embryos lived approximately 9 min longer than the mudskipper ones.

  7. G protein-gated IKACh channels as therapeutic targets for treatment of sick sinus syndrome and heart block. (United States)

    Mesirca, Pietro; Bidaud, Isabelle; Briec, François; Evain, Stéphane; Torrente, Angelo G; Le Quang, Khai; Leoni, Anne-Laure; Baudot, Matthias; Marger, Laurine; Chung You Chong, Antony; Nargeot, Joël; Striessnig, Joerg; Wickman, Kevin; Charpentier, Flavien; Mangoni, Matteo E


    Dysfunction of pacemaker activity in the sinoatrial node (SAN) underlies "sick sinus" syndrome (SSS), a common clinical condition characterized by abnormally low heart rate (bradycardia). If untreated, SSS carries potentially life-threatening symptoms, such as syncope and end-stage organ hypoperfusion. The only currently available therapy for SSS consists of electronic pacemaker implantation. Mice lacking L-type Cav1.3 Ca(2+) channels (Cav1.3(-/-)) recapitulate several symptoms of SSS in humans, including bradycardia and atrioventricular (AV) dysfunction (heart block). Here, we tested whether genetic ablation or pharmacological inhibition of the muscarinic-gated K(+) channel (IKACh) could rescue SSS and heart block in Cav1.3(-/-) mice. We found that genetic inactivation of IKACh abolished SSS symptoms in Cav1.3(-/-) mice without reducing the relative degree of heart rate regulation. Rescuing of SAN and AV dysfunction could be obtained also by pharmacological inhibition of IKACh either in Cav1.3(-/-) mice or following selective inhibition of Cav1.3-mediated L-type Ca(2+) (ICa,L) current in vivo. Ablation of IKACh prevented dysfunction of SAN pacemaker activity by allowing net inward current to flow during the diastolic depolarization phase under cholinergic activation. Our data suggest that patients affected by SSS and heart block may benefit from IKACh suppression achieved by gene therapy or selective pharmacological inhibition.

  8. Disturbances in atrial rhythm and conduction following the surgical creation of an atrial septal defect by the Blalock-Hanlon technique. (United States)

    Hamilton, S D; Bartley, T D; Miller, R H; Schiebler, G L; Marriott, H J


    Disturbances in atrial conduction or rhythm, or both, were found in 16 of 27 patients undergoing the surgical creation of an atrial septal defect by the Blalock-Hanlon technique. These included P-wave aberrations of intra-atrial block and ectopic atrial rhythm, A-V rhythm, A-V dissociation, sinus bradycardia, atrial flutter, escape-capture bigeminy, and atrial premature beats. Some of these were transient and occurred within 2 weeks after surgery. It seems likely that tissue trauma engendered by the clamp and resection of the atrial septum with possible injury to the internodal conducting pathways may be the genesis of these early postoperative disturbances. Of the eight cases with transient disturbances, six occurred in this period. Later changes, such as intra-atrial block, sinus bradycardia, and atrial flutter, may be attributed to changes in atrial size secondary to the postoperative pathophysiology. Digitalis intoxication and congestive heart failure cannot be excluded as contributory factors in either the early or the late disturbances. It was not possible to correlate the incidence and nature of these disturbances with morbidity and mortality. In such severely ill, cyanotic infants, irregularities, however slight, may have altered cardiac function significantly and contributed to their deaths.

  9. Direct and reflex cardiac bradydysrhythmias from small vagal nerve stiumaltions. (United States)

    Hageman, G R; Randall, W C; Armour, J A


    Alterations in cardiac pacemaker location, its rate of discharge, and A-V conduction patterns were induced in anesthetized adult dogs by electrical stimulation of the thoracic vagi and their small cardiac branches before and after cervical vagotomy. Electrical activity from small, contiguous bipolar silver electrodes was amplified and recorded by an optical oscillograph. The electrodes were located over the SA node, the three internodal pathways, the left atrium, and ventricular epicardium. A hoffman-type plaque electrode was placed over the A-V node to record a His bundle electrogram simultaneously with a Lead II electrocardiogram. Electrical stimulation of the intact left recurrent laryngeal nerve and its cardiac branches before and after vagotomy induced both direct and reflex effects on SA nodal cycle length. Efferent dromotropic effects on the A-V node varied from first- to third-degree heart block during stimulation of individual left recurrent cardiac branches. Stimulation of the right recurrent cardiac nerve induced atrial bradycardia with heart block above the His bundle. Stimulation of individual right vagal branches near the heart induced bradycardia, cardiac asystole, shifts in atrial pacemaker location, or activation of His pacemakers. Establishment of the His rhythm probably indicates selective inhibition of supraventricular but not of the His bundle. Asystole and His rhythms induced during stimulation of the more caudal branches of the right cardiac vagal nerves were generally reflexly mediated and were abolished by cervical vagotomy.

  10. [Late arrhythmias in the operated interatrial communication. Analysis of sinus node function and the conduction pathways by His bundle electrocardiography]. (United States)

    Ramírez, A; Gil, M; Martínez Ríos, M A; Cárdenas, M; Pliego, J; Zamora, C; Mata, L A


    Four hundred patients with atrial septal defect treated surgically were reviewed. Thirty five (8.7%) developed arrhytmias post-surgery which persisted for over a year. Sinus bradycardia was found in 10 patients, nodal rhythm in 21, and atrial fibrilation and flutter in 4 patients. Thirty five per cent of the patients with late arrhythmias developed related symptomatology. In 14 patients the function of the sinus node was studied with electrical stimulation of the atrium and with His registry. The interatrial conduction time, AV node and His Purkinje were analized employing various stimulation frequencies. All the cases studied had normal intra-atrial conduction; the response of the atrio-ventricular node to increasing frequencies was normal, an the intraventricular conduction remained constant. In 8 patients (52%), alterations of the sinus node were found; these consisted of prolonged post-stimulation pauses, Wenckebach's type sinoatrial block and suppression of sinus automatism employing vagal procedures or through electrical stimulation. A patient with severe bradycardia detected by dynamic electrocardiography had to be treated with a permanent pacemaker. We confirm that these arrhytmias are not produced by lesions of the internodal tracts, and that an alteration of the sinus node is frequent without a concomitant lesion of the intraventricular pathway. The lesion to the nutrient artery could be due to trauma and/or surgically induced. The response to anticholinergic drugs was good. Prolonged observation of these patients could increase the morbility of these arrythmias and raise doubts of the surgical indications in cases with moderate hemodynamic repercussion.

  11. Electrocardiographic changes in dog after injection of different doses of the venom of the scorpion Odonthobuthus

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    Sardar Jafari Shoorijeh


    Full Text Available There is scant information about biological effects of the venoms of scorpions on different organs. Sixteen healthy native dogs aged about 2 years with average body weight of 18.5 kg of both sexes were selected for this study. Dogs were divided randomly into four equal groups (4 dogs in each group. Clinical signs are recorded and electrocardiogram was obtained for each dog prior to injection of venom. In the control group 1 ml of saline solution was injected and the amount of equal to 0.1, 0.05 and 0.01 mg of venom powder per kg bwt were dissolved in 1 ml saline solution and injected intradermal in the abdominal region or hind limb of each dog in the second, third, and four groups, respectively. Clinical signs and electorcardiogram of each dog were recorded at different time intervals (5, 15, 30, 60, 90, 120, 180, 360 and 24 hours after injection of venom. The results of ECGs, in group 1 and 2 indicated advanced sinus arrhythmia, sinus arrest, sinoatrial standstill, sever bradycardia and tachycardia, first and second degree heart block, premature ventricular contraction, sinus bradycardia and ventricular fibrillation. In group 3, partial sinus arrhythmia, sinus tachycardia, sinus arrest, advanced sinus arrhythmia and tachycardia were observed. In conclusion, the venom of the scorpion Odonthobuthus produces very changes in electrocardiogram by its effects on autonomic system and adrenal gland.

  12. Hypovolemic shock: critical involvement of a projection from the ventrolateral periaqueductal gray to the caudal midline medulla. (United States)

    Vagg, D J; Bandler, R; Keay, K A


    Previous research has suggested that the ventrolateral column of the periaqueductal gray (vlPAG) plays a crucial role in triggering a decompensatory response (sympathoinhibition, hypotension, bradycardia) to severe blood loss. vlPAG excitation triggers also quiescence, decreased vigilance and decreased reactivity, the behavioral response which usually accompanies hypovolemic shock. The aim of this study was to identify, in unanesthetized rats, the main descending pathway(s) via which vlPAG neurons trigger sympathoinhibition and bradycardia in response to severe blood loss. Firstly, immediate early gene (c-Fos) expression was used to identify vlPAG neurons selectively activated by severe blood loss. Subsequently, the specific medullary projections of these vlPAG neurons were defined by combined c-Fos, retrograde tracing (double-label) experiments. It was found that vlPAG neurons selectively activated by severe hemorrhage project overwhelmingly to the vasodepressor portion of the caudal midline medulla (CMM). Previous studies indicate that this CMM region mediates behaviorally-coupled cardiovascular adjustments and the findings described here fit with the idea that CMM neurons are uniquely recruited by salient challenges, the adaptive responses to which require more than reflexive homeostatic cardiovascular adjustments.

  13. Modulation of heart rate by temporally patterned vagus nerve stimulation in the anesthetized dog. (United States)

    Yoo, Paul B; Liu, Haoran; Hincapie, Juan G; Ruble, Stephen B; Hamann, Jason J; Grill, Warren M


    Despite current knowledge of the myriad physiological effects of vagus nerve stimulation (VNS) in various mammalian species (including humans), the impact of varying stimulation parameters on nerve recruitment and physiological responses is not well understood. We investigated nerve recruitment, cardiovascular responses, and skeletal muscle responses to different temporal patterns of VNS across 39 combinations of stimulation amplitude, frequency, and number of pulses per burst. Anesthetized dogs were implanted with stimulating and recording cuff electrodes around the cervical vagus nerve, whereas laryngeal electromyogram (EMG) and heart rate were recorded. In seven of eight dogs, VNS-evoked bradycardia (defined as ≥10% decrease in heart rate) was achieved by applying stimuli at amplitudes equal to or greater than the threshold for activating slow B-fibers. Temporally patterned VNS (minimum 5 pulses per burst) was sufficient to elicit bradycardia while reducing the concomitant activation of laryngeal muscles by more than 50%. Temporal patterns of VNS can be used to modulate heart rate while minimizing laryngeal motor fiber activation, and this is a novel approach to reduce the side effects produced by VNS.

  14. Risk of cardiac arrhythmias during hypoglycemia in patients with type 2 diabetes and cardiovascular risk. (United States)

    Chow, Elaine; Bernjak, Alan; Williams, Scott; Fawdry, Robert A; Hibbert, Steve; Freeman, Jenny; Sheridan, Paul J; Heller, Simon R


    Recent trials of intensive glycemic control suggest a possible link between hypoglycemia and excess cardiovascular mortality in patients with type 2 diabetes. Hypoglycemia might cause arrhythmias through effects on cardiac repolarization and changes in cardiac autonomic activity. Our aim was to study the risk of arrhythmias during spontaneous hypoglycemia in type 2 diabetic patients with cardiovascular risk. Twenty-five insulin-treated patients with type 2 diabetes and a history of cardiovascular disease or two or more risk factors underwent simultaneous continuous interstitial glucose and ambulatory electrocardiogram monitoring. Frequency of arrhythmias, heart rate variability, and markers of cardiac repolarization were compared between hypoglycemia and euglycemia and between hyperglycemia and euglycemia matched for time of day. There were 134 h of recording at hypoglycemia, 65 h at hyperglycemia, and 1,258 h at euglycemia. Bradycardia and atrial and ventricular ectopic counts were significantly higher during nocturnal hypoglycemia compared with euglycemia. Arrhythmias were more frequent during nocturnal versus daytime hypoglycemia. Excessive compensatory vagal activation after the counterregulatory phase may account for bradycardia and associated arrhythmias. QT intervals, corrected for heart rate, >500 ms and abnormal T-wave morphology were observed during hypoglycemia in some participants. Hypoglycemia, frequently asymptomatic and prolonged, may increase the risk of arrhythmias in patients with type 2 diabetes and high cardiovascular risk. This is a plausible mechanism that could contribute to increased cardiovascular mortality during intensive glycemic therapy.

  15. Cardiac arrhythmias during or after epileptic seizures. (United States)

    van der Lende, Marije; Surges, Rainer; Sander, Josemir W; Thijs, Roland D


    Seizure-related cardiac arrhythmias are frequently reported and have been implicated as potential pathomechanisms of Sudden Unexpected Death in Epilepsy (SUDEP). We attempted to identify clinical profiles associated with various (post)ictal cardiac arrhythmias. We conducted a systematic search from the first date available to July 2013 on the combination of two terms: 'cardiac arrhythmias' and 'epilepsy'. The databases searched were PubMed, Embase (OVID version), Web of Science and COCHRANE Library. We attempted to identify all case reports and case series. We identified seven distinct patterns of (post)ictal cardiac arrhythmias: ictal asystole (103 cases), postictal asystole (13 cases), ictal bradycardia (25 cases), ictal atrioventricular (AV)-conduction block (11 cases), postictal AV-conduction block (2 cases), (post)ictal atrial flutter/atrial fibrillation (14 cases) and postictal ventricular fibrillation (3 cases). Ictal asystole had a mean prevalence of 0.318% (95% CI 0.316% to 0.320%) in people with refractory epilepsy who underwent video-EEG monitoring. Ictal asystole, bradycardia and AV-conduction block were self-limiting in all but one of the cases and seen during focal dyscognitive seizures. Seizure onset was mostly temporal (91%) without consistent lateralisation. Postictal arrhythmias were mostly found following convulsive seizures and often associated with (near) SUDEP. The contrasting clinical profiles of ictal and postictal arrhythmias suggest different pathomechanisms. Postictal rather than ictal arrhythmias seem of greater importance to the pathophysiology of SUDEP.


    Institute of Scientific and Technical Information of China (English)

    Chen Wang; James G.Whitwam


    Objective To investigate the roles of sympathetic and vagus nerves in hypotension and bradycardia induced by fentanyl.Methods Fourteen rabbits were divided into 2 groups: normal and vagotomized rabbits. Rabbits were anesthetized,paralyzed, and artificial ventilated. Right renal sympathetic nerve was exposed and prepared for recording electrical activity.Fentanyl was injected intravenously in incremental doses of 1, 4, 15, 30, and 50 μg/kg at 10 minutes intervals.Results Fentanyl significantly reduced the spontaneous activity of renal sympathetic nerve, mean arterial pressure, and heart rate above a total dose of 20 μg/kg in both normal and vagotomized rabbits. However, normal rabbits spontaneous sympathetic nerve activity and mean arterial pressure were more depressed than vagotomized rabbits at total doses of 50 and 100 μg/kg. There were no significant difference in the reduction of heart rate between normal and vagotomized rabbits.Conclusion Fentanyl induction of bradycardia and hypotension in rabbits is mainly due to depression of sympathetic nerve activity.

  17. A case of delayed cardiac perforation of active ventricular lead

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    Hangyuan Guo


    Full Text Available A 65-year-old man was admitted as for one month of repetitive dizziness and one episode of syncope. Electrocardiogram showed sinus bradycardia and his Holter monitoring also showed sinus bradycardia with sinus arrest, sino-atrial block and a longest pause of 4.3 s. Then sick sinus syndrome and Adam-Stokes syndrome were diagnosed. Then a dual chamber pacemaker (Medtronic SDR303 was implanted and the parameters were normal by detection. The patient was discharged 1 week later with suture removed. Then 1.5 month late the patient was presented to hospital once again for sudden onset of chest pain with exacerbation after taking deep breath. Pacemaker programming showed both pacing and sensing abnormality with threshold of?5.0V and resistance of 1200?. Lead perforation was revealed by chest X-ray and confirmed by echocardiogram. Considering the fact that there was high risk to remove ventricular lead, spiral tip of previous ventricular lead was withdrew followed by implantation of a new ventricular active lead to the septum. Previous ventricular lead was maintained. As we know that the complications of lead perforation in the clinic was rare. Here we discuss the clinical management and the possible reasons for cardiac perforation of active ventricular lead.

  18. Pharmacology of Casimiroa edulis; II. Cardiovascular effects in the anesthesized dog. (United States)

    Vidrio, H; Magos, G A


    The cardiovascular effects of an aqueous extract of seeds of Casimiroa edulis were assessed in pentobarbital-anesthetized dogs. The extract produced marked hypotension which lasted more than two hours; it was accompanied by moderate and less persistent bradycardia. The histaminergic nature of these effects was investigated in animals pretreated with the specific antagonists diphenhydramine, cimetidine, or a combination of both agents. These experiments showed that both H1- and H2-receptors were involved in the hypotensive response, while the bradycardia was mediated solely through an H1-mechanism. In open-chest dogs instrumented for recording cardiac output (ascending aortic flow), left ventricular contractility (dp/dt), central venous pressure (superior vena cava), systemic blood pressure, heart rate, total peripheral resistance and stroke volume, the extract decreased blood pressure and peripheral resistance and increased cardiac output and stroke volume, without modifying the other parameters. It was concluded that the cardiovascular pattern of Casimiroa edulis in the dog is that of a peripheral arterial vasodilator and that it increases cardiac output by reducing left ventricular afterload.

  19. Tachyphylaxis and sensitization to nicotine-induced tachycardiac and pressor effects after nicotine infusions. (United States)

    Cruz, S L; Vidrio, H


    This work examined the effects of nicotine on mean arterial pressure and heart rate in non-anesthetized spinal rats. Nicotine (200 mg/kg) was administered as a single bolus, as infusions lasting 7.5, 15 or 30 min, and as a post-infusion bolus. A nicotine bolus increased pressure and rate. These effects were less marked as the rate of infusion decreased. The infusions affected differentially the effects of a subsequent bolus. Thus, while tachycardia was decreased, the blood pressure rise was increased. An initial transient bradycardia was observed after bolus administration, but not during infusions; this effect was unchanged after post-infusion boluses. Pharmacological analysis indicated that tachycardia and bradycardia were predominantly due to ganglionic stimulation, while adrenal and sympathetic nerve catecholamine release played a major role in the pressor response. These results indicate that slow nicotine infusions do not induce tachyphylaxis for all of the cardiovascular effects of a subsequent bolus, and that development of acute tolerance appears to depend on the mechanism of action of the response.

  20. Reversal by hypothermia of vasodilator-induced tachycardia in anesthetized rats. (United States)

    Vidrio, H; García-Márquez, F


    The normal cardiovascular response to hydralazine in urethane-anesthetized rats, i.e. hypotension and tachycardia, was changed to hypotension and bradycardia if the body temperature of the animals was not maintained constant by external heating, but was allowed to decrease spontaneously throughout the experiment. A similar phenomenon was observed with diazoxide. In rats maintained at a rectal temperature of 31 degrees C, hydralazine bradycardia was partially blocked by a low dose of atropine and was reversed to tachycardia by a high dose of this agent; mecamylamine failed to influence heart rate lowering in this condition. Heart rate responses in unheated animals to acetylcholine and isopropylarterenol were respectively potentiated and depressed when compared to responses in heated rats. These findings suggest that cold-induced reciprocal changes in reactivity of cardiac muscarinic and beta-adrenoceptors may be responsible for reversal of hydralazine or diazoxide tachycardia in urethane-anesthetized hypothermic rats. As a result, cardiac stimulation by the sympatho-adrenal discharge induced by hypotension is inhibited, while cardiac depression which is apparently also induced by hypotension, is facilitated. It is speculated that vasopressin, released as a consequence of the blood pressure fall, could be this negative chronotropic factor.

  1. Exploring novel infusion regimens of phenylephrine during spinal anesthesia for caesarean delivery: The effects on hemodynamic control and fetal acid-base status

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    Syed N Muzaffar


    Materials and Methods: Ninety parturients undergoing SA for elective caesarean delivery received an IV infusion of phenylephrine in one of three different concentration ratios. The groups contained a potency equivalent of 100 μg/min, 80μg/min, and 60 μg/min infusion doses. The infusions were adjusted to maintain systolic blood pressure (SBP near the baseline until uterine incision. Hemodynamic changes in mother and umbilical cord blood gases were compared. Results: As concentration of phenylephrine increased, following significant trends were noticed: in group A, 10/29 (34.5% patients had hypotension as compared to 2/28 (7.4% patients in group B and 4/28 (14.3% patients in group C. On the other hand, we found that the incidence of hypertension and bradycardia was higher in groups B (22/28; 4/28 and C (26/28; 10/28 as compared to those in group A (3/29; 2/29, respectively. Neonatal acid-base status in all three groups was favorable. Conclusions: As the concentration of phenylephrine increased, the tendency for SBP to be above the baseline increased, along with an incidence of bradycardia. Therefore, we conclude that low dose infusion regimens of phenylephrine, i.e. between 60 μg/min and 80 μg/min, will be more effective in prevention of hypotension during SA for caesarean delivery.

  2. Cardiac output and vasodilation in the vasovagal response: An analysis of the classic papers. (United States)

    Wieling, Wouter; Jardine, David L; de Lange, Frederik J; Brignole, Michele; Nielsen, Henning B; Stewart, Julian; Sutton, Richard


    The simple faint is secondary to hypotension and bradycardia resulting in transient loss of consciousness. According to Ohm's law applied to the circulation, BP = SVR × CO, hypotension can result from a decrease in systemic vascular resistance (SVR), cardiac output (CO), or both. It is important to understand that when blood pressure (BP) is falling, SVR and CO do not change reciprocally as they do in the steady state. In 1932, Lewis, assuming that decreased SVR alone accounted for hypotension, defined "the vasovagal response" along pathophysiologic lines to denote the association of vasodilation with vagal-induced bradycardia in simple faint. Studies performed by Barcroft and Sharpey-Schafer between 1940 and 1950 used volume-based plethysmography to demonstrate major forearm vasodilation during extreme hypotension and concluded that the main mechanism for hypotension was vasodilation. Plethysmographic measurements were intermittent and not frequent enough to capture rapid changes in blood flow during progressive hypotension. However, later investigations by Weissler, Murray, and Stevens performed between 1950 and 1970 used invasive beat-to-beat BP measurements and more frequent measurements of CO using the Fick principle. They demonstrated that CO significantly fell before syncope, and little vasodilation occurred until very late in the vasovagal reaction Thus, since the 1970s, decreasing cardiac output rather than vasodilation has been regarded as the principal mechanism for the hypotension of vasovagal syncope.

  3. Induction of neonatal lupus in pups of mice immunized with synthetic peptides derived from amino acid sequences of the serotoninergic 5-HT4 receptor. (United States)

    Eftekhari, P; Roegel, J C; Lezoualc'h, F; Fischmeister, R; Imbs, J L; Hoebeke, J


    We have previously suggested that the recognition of a cross-reactive epitope on the 5-HT4 receptor and the 52-kDa SSA/Ro protein by serotonin-antagonizing autoantibodies could explain the electrophysiological symptoms of congenital heart block in neonatal lupus. To confirm this hypothesis, we immunized female mice with four synthetic peptides corresponding to the recognized epitopes. All mice developed anti-peptide antibodies, which cross-reacted with the Ro52 and 5-HT4 receptor peptides and recognized both cognate proteins. Peptide-immune mice were mated. The pups from mice immunized with the Ro52 peptides had no symptoms of neonatal lupus apart from bradycardia. However, pups from mice immunized with the 5-HT4 receptor peptides and bradycardia, atrioventricular block of type I or II, longer QT intervals, skin rashes and neuromotor problems. The 5-HT4 receptor was detectable in the different fetal tissues affected (heart, skin and brain) by immunohistochemistry. Hearts from diseased pups were less developed and showed disorganized myocardial hyperplasia, compared to the normal littermates. These results demonstrate that the serotoninergic 5-HT4 receptor is the antigenic target of physiopathological autoantibodies in neonatal lupus.

  4. Cardiac electrical defects in progeroid mice and Hutchinson–Gilford progeria syndrome patients with nuclear lamina alterations (United States)

    Rivera-Torres, José; Calvo, Conrado J.; Llach, Anna; Guzmán-Martínez, Gabriela; Caballero, Ricardo; González-Gómez, Cristina; Jiménez-Borreguero, Luis J.; Guadix, Juan A.; Osorio, Fernando G.; López-Otín, Carlos; Herraiz-Martínez, Adela; Cabello, Nuria; Vallmitjana, Alex; Benítez, Raul; Gordon, Leslie B.; Pérez-Pomares, José M.; Tamargo, Juan; Delpón, Eva; Hove-Madsen, Leif; Filgueiras-Rama, David; Andrés, Vicente


    Hutchinson–Gilford progeria syndrome (HGPS) is a rare genetic disease caused by defective prelamin A processing, leading to nuclear lamina alterations, severe cardiovascular pathology, and premature death. Prelamin A alterations also occur in physiological aging. It remains unknown how defective prelamin A processing affects the cardiac rhythm. We show age-dependent cardiac repolarization abnormalities in HGPS patients that are also present in the Zmpste24−/− mouse model of HGPS. Challenge of Zmpste24−/− mice with the β-adrenergic agonist isoproterenol did not trigger ventricular arrhythmia but caused bradycardia-related premature ventricular complexes and slow-rate polymorphic ventricular rhythms during recovery. Patch-clamping in Zmpste24−/− cardiomyocytes revealed prolonged calcium-transient duration and reduced sarcoplasmic reticulum calcium loading and release, consistent with the absence of isoproterenol-induced ventricular arrhythmia. Zmpste24−/− progeroid mice also developed severe fibrosis-unrelated bradycardia and PQ interval and QRS complex prolongation. These conduction defects were accompanied by overt mislocalization of the gap junction protein connexin43 (Cx43). Remarkably, Cx43 mislocalization was also evident in autopsied left ventricle tissue from HGPS patients, suggesting intercellular connectivity alterations at late stages of the disease. The similarities between HGPS patients and progeroid mice reported here strongly suggest that defective cardiac repolarization and cardiomyocyte connectivity are important abnormalities in the HGPS pathogenesis that increase the risk of arrhythmia and premature death. PMID:27799555

  5. Neuronal counting and parasympathetic dysfunction in the hearts of chronically Trypanosoma cruzi - infected rats Contagem neuronal e disfunção cardíaca parassimpática em ratos cronicamente infectados pelo Trypanosoma cruzi

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    E. Chapadeiro


    Full Text Available Ten male Wistar rats, chronically infected with Colombian, São Felipe (12SF and Y strains of Trypanosoma cruzi and ten non-infected control animals were submitted to the bradycardia responsiveness test, an assessment of heart parasympathetic function, after phenylephrine injection. Six chagasic animals showed heart parasympathetic dysfuntion characterized by reduction in the index of bradycardia baroreflex responsiveness, as compared with the control group. Microscopic examination of the atrial heart ganglia of chagasic rats showed ganglionitis, but no statiscally significant reduction in the number of neurons.Dez ratos machos Wistar cronicamente infectados pelas cepas Colombiana, São Felipe (12SF, e Y do Trypanosoma cruzi, foram submetidos, após 8 meses de infecção, juntamente com dez animais controles, ao teste da resposta bradicárdica barorreflexa pela injeção endovenosa de fenilefrina. Seis ratos chagásicos exibiram disfunção cardíaca parassimpática, caracterizada pela depressão do índice da resposta bradicárdica barorreflexa. Embora o estudo histológico dos corações chagásicos mostrasse lesões dos gânglios atriais, a contagem dos neurônios em cortes seriados, não apresentou redução numérica significativa dos mesmos.

  6. Postoperative use of analgesics in dogs and cats by Canadian veterinarians. (United States)

    Dohoo, S E; Dohoo, I R


    Four hundred and seventeen Canadian veterinarians were surveyed to determine their postoperative use of analgesics in dogs and cats following 6 surgical procedures, and to determine their opinions toward pain perception and perceived complications associated with the postoperative use of potent opioid analgesics. Three hundred and seventeen (76%) returned the questionnaire. The percentage of animals receiving analgesics postoperatively ranged from 84% of dogs and 70% of cats following orthopedic surgery to 10% of dogs and 9% of cats following castration. In general, with the exception of orthopedic surgery, roughly equal percentages of dogs and cats received postoperative analgesics. Opioids were used almost exclusively to provide postoperative analgesia, with butorphanol the most commonly administered drug to both dogs and cats. Analgesics were usually administered either once or twice postoperatively. With regard to the administration of potent opioid agonists, the 3 major concerns included respiratory depression, bradycardia, and sedation in dogs, and excitement, respiratory depression, and bradycardia in cats. Seventy-seven percent of veterinarians considered their knowledge of issues related to the recognition and control of postoperative pain to be inadequate. Experience in practice is currently the major source of knowledge, with undergraduate veterinary school and research articles in journals ranked as the least important sources. Lectures or seminars delivered at the regional level were the preferred format for continuing education.

  7. Cutaneous absorption of Oleander: Fact or fiction

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    Senthilkumaran S


    Full Text Available Cardiac conduction disorders following oral ingestion of Oleander plant materials were documented earlier. Transcutaneous absorption of yellow oleander (Thevetia peruviana leaf extract applied over non intact skin (raw wound resulting in reversible cardiac conduction disorder observed in four healthy males who were free from any other systemic or electrolyte or metabolic disorders or exposure to pesticide or toxins is reported for the first time. Their hematological, biochemical, clinical, and echocardiogram status were within normal limits and free of any abnormalities. One among the four, presented for weakness and breathlessness (class II. He had bradycardia with Mobitz II block and hypotension without any other demonstrable localizing signs. The other three were identified in the community and without any symptoms. However, their ECG revealed bradycardia with Mobitz I block in two and complete heart block in the other. All of the four recovered well without any untoward events. Hence, it is suggested that physicians and practitioners have to elicit history and route of administration of unconventional therapy, whenever they are confronted with clinical challenges and during medical emergencies before embarking final decision.

  8. Large outbreaks of ciguatera after consumption of brown marbled grouper. (United States)

    Chan, Thomas Y K


    Brown marbled grouper (Epinephelus fuscoguttatus) is an apex predator from coral reefs of the Indo-Pacific region. All five published case series of ciguatera after consumption of brown marbled grouper were reviewed to characterize the types, severity and chronicity of ciguatera symptoms associated with its consumption. Three of these case series were from large outbreaks affecting over 100-200 subjects who had eaten this reef fish served at banquets. Affected subjects generally developed a combination of gastrointestinal, neurological and, less commonly, cardiovascular symptoms. Gastrointestinal symptoms occurred early and generally subsided in 1-2 days. Some neurological symptoms (e.g., paresthesia of four limbs) could last for weeks or months. Sinus bradycardia and hypotension occurred early, but could be severe and prolonged, necessitating the timely use of intravenous fluids, atropine and dopamine. Other cardiovascular and neurological features included atrial ectopics, ventricular ectopics, dyspnea, chest tightness, PR interval >0.2 s, ST segment changes, polymyositis and coma. Concomitant alcohol consumption was associated with a much higher risk of developing bradycardia, hypotension and altered skin sensation. The public should realize that consumption of the high-risk fish (especially the ciguatoxin-rich parts and together with alcohol use) and repeated ciguatoxin exposures will result in more severe and chronic illness.

  9. Studies on the desensitization of the central cardiovascular responses of histamine. (United States)

    Poulakos, J J; Gertner, S B


    Intraventricular administration of histamine (HA) in conscious freely moving rats produces a dose-dependent pressor response and bradycardia. These responses are diminished profoundly when a second injection of HA is given within a short time after the first injection. In this study, the specific HA H1 agonist, pyridylethylamine, and the specific H2 agonist, impromidine, were used to examine the nature of this tachyphylaxis. Blood pressure and heart rate were measured directly from indwelling carotid catheters, and drugs were administered in three consecutive intraventricular injections to conscious freely moving rats at 30-min intervals. HA, the H2 agonist, impromidine and the combined injection of pyridylethylamine and impromidine induced tachyphylaxis of the pressor response. The H1 agonist, pyridylethylamine and the HA-N-methyltransferase inhibitor, SKF-91488 (homodimaprit) did not show tachyphylaxis. Heart rate responses were more complex and only HA demonstrated tachyphylaxis of the bradycardia. It is concluded that the tachyphylaxis of the pressor response caused by repeated injections of HA results from the desensitization of central HA H2 receptors.

  10. Anti-Arrhythmic Potential of Coriandrum sativum Seeds in Salt Induced Arrhythmic Rats

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    Nida Rehman1, Nazish Jahan1*, Khalil-ul-Rahman2, Khalid Mahmood Khan2 and Fatiqa Zafar1


    Full Text Available In the present research, the anti-arrhythmic potential of Coriandrum sativum (seeds was evaluated in BaCl2 induced tachycardia and KCl induced bradycardia in rats. Heart rate and electrocardiogram (ECG was recorded during the experimental period. The BaCl2 increased the heart rate from 111/min to 157/min while KCL decreased the heart rate from 112/min to 60/min in the rats of positive control groups. ECG patterns also confirmed the tachy- and brady-arrhythmia in the rats of both positive control groups. The changes in biochemical cardiac biomarkers (CK-MB, LDH, AST, and ALT were also the studied parameters. The level of cardiac biomarkers was significantly elevated in the serum of positive control rats as compared to their respective absolute controls. In case of both curative and preventive mode of treatment the elevated levels of enzymes, cardiac biomarkers were significantly reduced. Electrocardiogram (ECG pattern revealed that the studied plant possesses a very good anti-arrhythmic potential in case of curative mode of treatment. The antiarrhythmic potential through preventive mode of treatment was also encouraging, but comparatively less than the curative mode of treatment. Anti-tachycardial potential of C. sativum was comparable with standard drug while, recovery in bradycardia was relatively slow than standard drug. Gross pathology and ECG pattern of base line group confirmed the innoxious nature of C. sativum seeds. Treatment of rats with Coriandrum sativum (100 mgkg-1 BW normalized the heart rate and attenuated the cardiac arrhythmia.

  11. Hemodynamic and respiratory responses to microinjection of ATP into the intermediate and caudal NTS of awake rats. (United States)

    Antunes, Vagner R; Bonagamba, Leni G H; Machado, Benedito H


    The nucleus tractus solitarii (NTS) is the site of integration of the peripheral chemoreceptor afferents in the brainstem. Previous studies from our laboratory have shown that microinjection of ATP into the intermediate NTS produced increases in arterial pressure and bradycardia. In the present study, we evaluated the hemodynamic and respiratory responses to microinjection of ATP into the intermediate and caudal commissural NTS. In the same group of rats the responses were compared with cardiorespiratory responses to chemoreflex activation (KCN, i.v.). The data show that microinjection of ATP into the intermediate NTS produced pressor and bradycardic responses similar to those observed in response to chemoreflex activation but apnoea instead of tachypnoea. Microinjection of ATP into caudal commissural NTS produced increase in arterial pressure and tachypnoea similar to the chemoreflex but a minor bradycardia. The data show that microinjection of ATP into different sub-regions of the NTS produces a diverse pattern of hemodynamic and respiratory responses and suggest the involvement of this purine in the neurotransmission of the cardiovascular reflex in the NTS.

  12. Nitric oxide modulates the cardiovascular effects elicited by acetylcholine in the NTS of awake rats. (United States)

    da Silva, Liana Gouveia; Dias, Ana Carolina Rodrigues; Furlan, Elaina; Colombari, Eduardo


    Microinjection of acetylcholine chloride (ACh) in the nucleus of the solitary tract (NTS) of awake rats caused a transient and dose-dependent hypotension and bradycardia. Because it is known that cardiovascular reflexes are affected by nitric oxide (NO) produced in the NTS, we investigated whether these ACh-induced responses depend on NO in the NTS. Responses to ACh (500 pmol in 100 nl) were strongly reduced by ipsilateral microinjection of the NOS inhibitor NG-nitro-L-arginine methyl ester (L-NAME; 10 nmol in 100 nl) in the NTS: mean arterial pressure (MAP) fell by 50 +/- 5 mmHg before L-NAME to 9 +/- 4 mmHg, 10 min after L-NAME, and HR fell by 100 +/- 26 bpm before L-NAME to 20 +/- 10 bpm, 10 min after L-NAME (both P NTS also reduced responses to ACh: MAP fell from 42 +/- 3 mmHg before TRIM to 27 +/- 6 mmHg, 10 min after TRIM (P NTS of conscious rats induces hypotension and bradycardia, and these effects may be mediated at least partly by NO produced in NTS neurons.

  13. Directory of Open Access Journals (Sweden)


    Full Text Available It is well known that pharmacological therapy of bradycardia caused by sinus node dysfunction is not effective. The optimal therapy to be used is the implantation of the pacemaker. According to different assessments, the sick sinus syndrome is the most common cause for the implantation of the pacemaker. The expected positive outcome of the implantation of the permanent pacemaker is largely dependent on the indications for the implantation and programmed parameters. Bradycardia in the sick sinus syndrome patients can be treated using the AAIR single chamber pacing or DDDR dual-chamber atrioventricular pacing. The intactness of the atrioventricular conduction needs to be ensured in the course of the AAIR pacing. In case there is an atrioventricular block, single-chamber atrial pacing cannot protect the patient from bradycardia and the consequences it may lead to. In contrast, DDDR pacing is helpful in an AV block but may pose a threat to the right ventricle, which may cause a change in the way the ventricles are activated and contracted. These phenomenon may result in the remodelling of the ventricles and dilatation of the left atrium which are associated with higher risks of atrial fibrillation and heart failure. According to the latest data,there are no significant differences in all-cause mortality of patients with AAIR and DDDR pacing with prolonged AV delay. It was shown the AAIR pacing was associated with more frequent paroxymal atrial fibrillation and twice as many pacing system replacement reoperations. It is noteworthy, though, that the data obtained following the randomized studies need to be interpreted with caution since the patient selection criteria were central to the reviewed research. It is also to be mentioned that the AAIR pacing is fairly simple, efficient and safe in meticulously selected patients, while an inappropriate choice of the DDDR pacing parameters may aggravate the regional myocardial contractility and ejection

  14. Control of cardiorespiratory function in response to hypoxia in an air-breathing fish, the African sharptooth catfish, Clarias gariepinus. (United States)

    Belão, T C; Zeraik, V M; Florindo, L H; Kalinin, A L; Leite, C A C; Rantin, F T


    We evaluated the role of the first pair of gill arches in the control of cardiorespiratory responses to normoxia and hypoxia in the air-breathing catfish, Clarias gariepinus. An intact group (IG) and an experimental group (EG, bilateral excision of first gill arch) were submitted to graded hypoxia, with and without access to air. The first pair of gill arches ablations reduced respiratory surface area and removed innervation by cranial nerve IX. In graded hypoxia without access to air, both groups displayed bradycardia and increased ventilatory stroke volume (VT), and the IG showed a significant increase in breathing frequency (fR). The EG exhibited very high fR in normoxia that did not increase further in hypoxia, this was linked to reduced O2 extraction from the ventilatory current (EO2) and a significantly higher critical O2 tension (PcO2) than the IG. In hypoxia with access to air, only the IG showed increased air-breathing, indicating that the first pair of gill arches excision severely attenuated air-breathing responses. Both groups exhibited bradycardia before and tachycardia after air-breaths. The fH and gill ventilation amplitude (VAMP) in the EG were overall higher than the IG. External and internal NaCN injections revealed that O2 chemoreceptors mediating ventilatory hypoxic responses (fR and VT) are internally oriented. The NaCN injections indicated that fR responses were mediated by receptors predominantly in the first pair of gill arches but VT responses by receptors on all gill arches. Receptors eliciting cardiac responses were both internally and externally oriented and distributed on all gill arches or extra-branchially. Air-breathing responses were predominantly mediated by receptors in the first pair of gill arches. In conclusion, the role of the first pair of gill arches is related to: (a) an elevated EO2 providing an adequate O2 uptake to maintain the aerobic metabolism during normoxia; (b) a significant bradycardia and increased fAB elicited

  15. The clinical value of dexmedetomidine during mechanical ventilation in ICU patients of different ages

    Directory of Open Access Journals (Sweden)

    Yan ZHU


    Full Text Available Objectives To provide basis for the safe use of indigenous dexmedetomidine hydrochloride by observing its sedative effect and safety when it was given to mechanically ventilated patients of different ages. Methods Three hundred and fourteen mechanically ventilated patients were admitted to our ICU. According to the age, patients were divided into two subgroups: group A (25-50 years old and group B (51-80 years old, with 157 patients in each group. Dexmedetomidine was given to achieve the target sedation level (Ramsay score 3. The changes in noninvasive blood pressure (SBP, DBP, MAP, heart rate, SpO2, respiratory rate and FiO2 were continuously monitored and recorded before treatment (T1, and 10min (T2, 30min (T3 and 120min (T4 after drug administration, on the instant moment of extubation (T5, and 30min after extubation (T6. The adverse reactions such as hypertension, hypotension, bradycardia, tachycardia, delirium were also observed and recorded after treatment. Results Patients of both A and B groups showed a lowering of SBP, DBP, MAP and HR after treatment with dexmedetomidine, especially in group B(P80mmHg, HR>60 times/min. Respiratory rate was reduced (P0.05. SpO2 was not reduced, and it even rose 30min after administration of dexmedetomidine (P0.05, and the heart rate was slightly slower in group B (P<0.05. The probability of occurrence of adverse reactions, such as hypertension, hypotension, tachycardia, bradycardia and delirium was significantly higher in group B than in group A. Conclusions Dexmedetomidine does not depress respiration, and a stable hemodynamics was maintained after extubation in ICU patients undergoing mechanical ventilation, thus it is an ideal sedative drug. But when it is used in elderly patients, proper monitoring should be maintained, especially when a loading dose is used, in order to prevent adverse reactions such as hypotension and bradycardia, and should be corrected in time. DOI: 10.11855/j.issn.0577-7402.2015.09.15

  16. Unusual Presentation of Dengue Fever; A child with acute myocarditis

    Directory of Open Access Journals (Sweden)

    Moaz Aslam


    Full Text Available Dengue fever (DF is an acute febrile illness that follows a self-limiting course. However, some patients suffer from complications, including myocarditis, due to the involvement of other organs. A child presented at the Aga Khan University Hospital in Karachi, Pakistan, in June 2013 with a high-grade fever, malaise and epigastric pain radiating to the chest. Positive DF antigen and immunoglobulin M assays confirmed the diagnosis of DF. Persistent bradycardia with low blood pressure led to further cardiac investigations which showed a decreased ejection fraction and raised serum cardiac enzymes, indicating myocardial damage. With supportive care and use of inotropes, the spontaneous normalisation of cardiac enzyme levels and ejection fraction was observed. The child was discharged five days after admission. This case highlights the importance of identifying myocarditis in DF patients suffering from cardiac symptoms that are not explained by other potential aetiologies. Awareness, early suspicion and supportive care are essential to ensure favourable outcomes.

  17. [Development of oral feeding skills in the preterm infant]. (United States)

    Lau, C


    Preterm infants cannot readily transition from tube to oral feeding. Such difficulty often delays their discharge from the hospital and mother-infant reunion. Therefore, understanding the development of the necessary skills preterm infants need to acquire for safe and successful oral feeding is essential. It is now recognized that a mature sucking pattern consisting of the rhythmic alternation of suction and expression is not sufficient for an infant to feed by mouth safely. Rather, an adequate coordination of sucking, swallowing, and respiration appear to be crucial if the infant is to feed with no episodes of desaturation, apnea, bradycardia, and/or aspiration. Studies have shown the benefits of some interventions in facilitating oral feeding in the preterm infant. However, it remains to be determined whether these effects can be generalized.

  18. Sleep Disorders: Is the Trigemino-Cardiac Reflex a Missing Link? (United States)

    Chowdhury, Tumul; Bindu, Barkha; Singh, Gyaninder Pal; Schaller, Bernhard


    Trigeminal innervated areas in face, nasolacrimal, and nasal mucosa can produce a wide array of cardiorespiratory manifestations that include apnea, bradypnea, bradycardia, hypotension, and arrhythmias. This reflex is a well-known entity called “trigemino-cardiac reflex” (TCR). The role of TCR is investigated in various pathophysiological conditions especially in neurosurgical, but also skull base surgery procedures. Additionally, its significance in various sleep-related disorders has also been highlighted recently. Though, the role of diving reflex, a subtype of TCR, has been extensively investigated in sudden infant death syndrome. The data related to other sleep disorders including obstructive sleep apnea, bruxism is very limited and thus, this mini review aims to investigate the possible role and correlation of TCR in causing such sleep abnormalities.

  19. Cardiotoxicity associated with the synthetic cannabinoid, K9, with laboratory confirmation. (United States)

    Young, Amy C; Schwarz, Evan; Medina, Genevieve; Obafemi, Adebisi; Feng, Sing-Yi; Kane, Colin; Kleinschmidt, Kurt


    Synthetic cannabinoids have been popular recreational drugs of abuse for their psychoactive properties. Five of the many synthetic cannabinoids have been recently banned in the United States because of their unknown and potentially harmful adverse effects. Little is known about these substances. They are thought to have natural cannabinoid-like effects but have different chemical structures. Adverse effects related to synthetic cannabinoids are not well known. We provide clinical effects and patient outcome following K9 use. In addition, we briefly review synthetic cannabinoids. We present a 17-year-old adolescent boy with chest pain, tachycardia, and then bradycardia associated with smoking K9. Two synthetic cannabinoids, JWH-018 and JWH-073, were confirmed on laboratory analysis. In addition to the limited current data, we demonstrate harmful adverse effects related to toxicity of 2 synthetic cannabinoids. Further studies are needed.

  20. Sepsis and siderosis, Yersinia enterocolitica and hereditary haemochromatosis. (United States)

    Thwaites, Phoebe A; Woods, Marion L


    A 60-year-old woman was admitted with sepsis, relative bradycardia, CT evidence of numerous small liver abscesses and 'skin bronzing' consistent with hereditary haemochromatosis (HH). Yersinia enterocolitica O:9 infection was confirmed by serology specimens taken 10 days apart. Iron overload was detected, and homozygous C282Y gene mutation confirmed HH. Liver biopsy revealed grade IV siderosis with micronodular cirrhosis. Haemochromatosis is a common, inherited disorder leading to iron overload that can produce end-organ damage from excess iron deposition. Haemochromatosis diagnosis allowed aggressive medical management with phlebotomy achieving normalisation of iron stores. Screening for complications of cirrhosis was started that included hepatoma surveillance. Iron overload states are known to increase patient susceptibility to infections caused by lower virulence bacteria lacking sophisticated iron metabolism pathways, for example, Yersinia enterocolitica Although these serious disseminated infections are rare, they may serve as markers for occult iron overload and should prompt haemochromatosis screening.

  1. The Influence for Heart and Blood Vessel of Resperdone%利培酮对心血管的影响

    Institute of Scientific and Technical Information of China (English)

    丁智平; 戴兴海; 廖慧珍


    Objective To research the influence of the Risperidone for heart and blood vessel and to contral for Clozapine. Method Schizophrenic patients who were in hospital and conform to diagnostic criteria of CCMD- 2- R were been divided Risperidone group and Clozapine group. Two group patients were been examined EKG before and after treatment one、two、three months. Results The influence for heart and blood vessel of Risperidone group were mainly Sinus bradycardia and T wave change but lower for Clozapine group. The influence was associated with the time of taking the drugs Conclusion There was influence on heart and blood vessel of Risperidone but the extend of influencc was lower for Clozapine and must give rise to pay attention.

  2. Effects of early and late-onset treatment with carvedilol in an experimental model of aortic regurgitation

    DEFF Research Database (Denmark)

    Eskesen, Kristian; Olsen, Niels Thue; Dimaano, Veronica L;


    in several studies. METHOD: Thirty-nine Sprague-Dawley rats with AR were randomized to ten weeks of medical treatment with carvedilol or no treatment. Treatment was initiated either early or late after AR induction. The effect of carvedilol was assessed by serial echocardiography and invasive hemodynamic...... measurements. RESULTS: AR resulted in eccentric hypertrophy and left ventricular (LV) dysfunction. LV remodeling and function as measured by echocardiography was unaffected by treatment. LV dimensions were similar between treated and untreated groups and measures of LV performance (including strain and strain....... CONCLUSION: Carvedilol did not improve left ventricular remodeling or function in rats with surgically induced AR. Despite relative bradycardia, we did not find carvedilol to negatively impact the heart, either when treatment was initiated early or late in the course of disease....

  3. When Threat Is Near, Get Out of Here: Dynamics of Defensive Behavior During Freezing and Active Avoidance. (United States)

    Löw, Andreas; Weymar, Mathias; Hamm, Alfons O


    When detecting a threat, humans and other animals engage in defensive behaviors and supporting physiological adjustments that vary with threat imminence and potential response options. In the present study, we shed light on the dynamics of defensive behaviors and associated physiological adjustments in humans using multiple psychophysiological and brain measures. When participants were exposed to a dynamically approaching, uncontrollable threat, attentive freezing was augmented, as indicated by an increase in skin conductance, fear bradycardia, and potentiation of the startle reflex. In contrast, when participants had the opportunity to actively avoid the approaching threat, attention switched to response preparation, as indicated by an inhibition of the startle magnitude and by a sharp drop of the probe-elicited P3 component of the evoked brain potentials. These new findings on the dynamics of defensive behaviors form an important intersection between animal and human research and have important implications for understanding fear and anxiety-related disorders.

  4. The real-life experience with cardiovascular complications in the first dose of fingolimod for multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Yara Dadalti Fragoso


    Full Text Available Fingolimod is a new and efficient treatment for multiple sclerosis (MS. The drug administration requires special attention to the first dose, since cardiovascular adverse events can be observed during the initial six hours of fingolimod ingestion. The present study consisted of a review of cardiovascular data on 180 patients with MS receiving the first dose of fingolimod. The rate of bradycardia in these patients was higher than that observed in clinical trials with very strict inclusion criteria for patients. There were less than 10% of cases requiring special attention, but no fatal cases. All but one patient continued the treatment after this initial dose. This is the first report on real-life administration of fingolimod to Brazilian patients with MS, and one of the few studies with these characteristics in the world.

  5. An update on risk factors for drug-induced arrhythmias. (United States)

    Vlachos, Konstantinos; Georgopoulos, Stamatis; Efremidis, Michael; Sideris, Antonios; Letsas, Konstantinos P


    A variety of drugs, either anti-arrhythmics or non-antiarrhythmics, have been associated with drug-induced arrhythmias. Drug-induced arrhythmias are usually observed in the presence of long QT interval or Brugada electrocardiographic pattern. Clinical risk factors, such as female gender, structural heart disease, metabolic and electrolyte abnormalities, bradycardia and conduction disease, increased drug bioavailability, and silent channelopathies act as ''effect amplifiers'' which can make an otherwise relatively safe drug dangerous with regard to risk for polymorphic ventricular tachycardia in the setting of QT interval prolongation. A drug-induced type 1 electrocardiographic pattern of Brugada syndrome is considered highly proarrhythmic. Specific electrocardiographic markers including the corrected QT interval, QRS duration, Tpeak-Tend/QT ratio, and others may predict the risk of arrhythmias in both situations. The present review highlights on the current clinical and electrocardiographic risk factors for prediction of drug-induced arrhythmias.

  6. Hypotensive activity of terpenes found in essential oils. (United States)

    Menezes, Igor A C; Barreto, Carmélia M N; Antoniolli, Angelo R; Santos, Márcio R V; de Sousa, Damião P


    The cardiovascular activity of essential oils has been reported. Some studies showed that the main chemical components of these oils contribute to their pharmacological activity. Therefore, the cardiovascular activity of four monoterpenes and one sesquiterpene was evaluated in the present work. In non-anaesthetized normotensive rats, (+)-alpha-pinene, (-)-beta-pinene, (+/-)-citronellol and (+/-)-linalool (1, 5, 10, and 20 mg/kg, i.v.) induced hypotension [maximal effect: (-35 +/- 3)%, (-46 +/- 4)%, (-48 +/- 2)% and (-40 +/- 2)%, respectively; n=6] and tachycardia [maximal effect: (13 +/- 4)%, (16 +/- 7)%, (21 +/- 1)% and (19 +/- 3)%, respectively; n=6] while (-)-a-bisabolol (1, 5, 10, and 20 mg/kg, i.v.) induced hypotension [maximal effect: (-47 +/- 8)%, n=6] and bradycardia [maximal effect: (-57 +/- 3)%]. In conclusion, these results demonstrated that all terpenes tested had hypotensive activity in rats and that the pharmacological effect of the terpene alcohols was more effective than that of the terpene hydrocarbons.

  7. Oculocardiac reflex during strabismus surgery

    Directory of Open Access Journals (Sweden)

    Mehryar Taghavi Gilani


    Full Text Available The activation of oculucardiac reflex (OCR is common during the strabismus surgeries. OCR is known as a trigemino-vagal reflex, which leads to the various side effects including bradycardia, tachycardia, arrhythmia, or in some cases cardiac arrest. This reflex could be activated during intraorbital injections, hematomas, and mechanical stimulation of eyeball and extraocular muscles surgeries. The incidence of OCR varies in a wide range, from 14% to 90%, that depends on anesthetic strategy and drug used for the surgery. The efficacy of various anticholinergic and anesthetic agents on declining the OCR reflex has been evaluated in different studies, especially in children. Although the detection of OCR goes back to 1908, its exact effect is not well recognized during strabismus surgery. In this review, we aimed to summarize the studies investigated the efficacy and potential of various anesthetic medications on inhibiting the OCR in children undergoing strabismus surgery.

  8. MTO1-deficient mouse model mirrors the human phenotype showing complex I defect and cardiomyopathy.

    Directory of Open Access Journals (Sweden)

    Lore Becker

    Full Text Available Recently, mutations in the mitochondrial translation optimization factor 1 gene (MTO1 were identified as causative in children with hypertrophic cardiomyopathy, lactic acidosis and respiratory chain defect. Here, we describe an MTO1-deficient mouse model generated by gene trap mutagenesis that mirrors the human phenotype remarkably well. As in patients, the most prominent signs and symptoms were cardiovascular and included bradycardia and cardiomyopathy. In addition, the mutant mice showed a marked worsening of arrhythmias during induction and reversal of anaesthesia. The detailed morphological and biochemical workup of murine hearts indicated that the myocardial damage was due to complex I deficiency and mitochondrial dysfunction. In contrast, neurological examination was largely normal in Mto1-deficient mice. A translational consequence of this mouse model may be to caution against anaesthesia-related cardiac arrhythmias which may be fatal in patients.

  9. A video-polygraphic analysis of the cataplectic attack

    DEFF Research Database (Denmark)

    Rubboli, G; d'Orsi, G; Zaniboni, A


    with bradycardia, that was maximal during the atonic phase. CONCLUSIONS: Analysis of the muscular phenomena that characterize cataplectic attacks in a standing patient suggests that the cataplectic fall occurs with a pattern that might result from the interaction between neuronal networks mediating muscular atonia......OBJECTIVES AND METHODS: To perform a video-polygraphic analysis of 11 cataplectic attacks in a 39-year-old narcoleptic patient, correlating clinical manifestations with polygraphic findings. Polygraphic recordings monitored EEG, EMG activity from several cranial, trunk, upper and lower limbs...... muscles, eye movements, EKG, thoracic respiration. RESULTS: Eleven attacks were recorded, all of them lasting less than 1 min and ending with the fall of the patient to the ground. We identified, based on the video-polygraphic analysis of the episodes, 3 phases: initial phase, characterized essentially...

  10. Analysis of sertraline-only overdoses. (United States)

    Klein-Schwartz, W; Anderson, B


    Sertraline is an antidepressant for which preliminary data suggest a low inherent toxicity. Previously reported case series have included coingestants or had small numbers of patients. This study was undertaken to determine the toxicity of overdoses of sertraline alone. A 2-year retrospective and 6-month prospective study was conducted at a regional poison center. There were 52 patients with a mean age of 19.3 +/- 13.8 years and a mean dose of 727 +/- 686 mg. There were no symptoms in 34 cases. Symptomatic patients experienced mild central nervous system, cardiovascular, and gastrointestinal effects. Two patients developed bradycardia which resolved without therapy. While all but 3 of 38 adolescents and adults were treated in a health care facility, 10 of 14 children were managed at home. Gastrointestinal decontamination was performed in 37 cases. No other specific therapy was required. Serious toxicity would not be expected following sertraline-only overdoses.

  11. The case of malignancy mimicking legionella pneumonia

    Directory of Open Access Journals (Sweden)

    Ali Karakuş


    Full Text Available Legionella pneumophila is a bacterium, which can grow inwater pipe networks and climate systems. Contaminationoccurs by aspiration of infected water or aerosol inhalation.It is usually presented with fever, bradycardia, andchange in mental status, hyponatremia, elevation of liverenzymes and deterioration of renal function. The definitediagnosis is established by detection of the antigens andcultivating in the culture medium. Also, malign lung tumorscan encounter with the same clinical findings, so lungcancer should be remembered in differential diagnosis.The patient hospitalized for the Legionella pneumophiladue to the physical examination and laboratory findingsduring the first evaluation in the emergency department.However, further examinations pointed to the cancer. Weaimed to emphasize the probability of malignant tumorsin terms of hyponatremia, increase in the liver enzymes,and failure in the renal functions, which were usually experiencedin emergency unit. J Clin Exp Invest 2013; 4(3: 390-392Key words: Legionella pneumophila, pneumonia, lung malignancy

  12. Neonatal molecular pathologies induced by maternal anti-Ro and anti-La antibodies

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    Herrera-Esparza R


    Full Text Available Maternal antinuclear antibodies with anti-Ro or anti-La specificity might be pathogenic to the fetus and could induce molecular neonatal pathologies, such as neonatal lupus (NL with or without congenital heart block (CHB. The cutaneous manifestations of neonatal lupus appear at birth or a few weeks later, and skin lesions may persist for weeks. While CHB is characterized by intrauterine bradycardia or low heart rates at birth and may persist for months, depending on the degree of blockage. Clinical and experimental data demonstrated that anti-Ro and anti-La autoantibodies functionally inhibit L-type calcium channels and induce abnormalities in electrical conduction of the cardiac myocytes. It has been 38 years since the first clinical description of CHB. Presently, the pathophysiology of CHB has been clarified through clinical and basic research studies.

  13. Dexmedetomidine overdosage: An unusual presentation

    Directory of Open Access Journals (Sweden)

    Soumya S Nath


    Full Text Available We present a case of dexmedetomidine toxicity in a 3-year-old child. The case report describes the features and outlines the treatment strategy adopted. The child presented with bradypnoea, bradycardia, hypotension, deep hypnosis and miosis. He was successfully managed with oxygen, saline boluses and adrenaline infusion. He became haemodynamically stable with adrenaline infusion. He started responding to painful stimuli in 3 h and became oriented in 7 h. Dexmedetomidine, a selective α2 adrenoceptor agonist, is claimed to have a wide safety margin. This case report highlights the fact that dexmedetomidine administered in a toxic dose may be life-threatening may present with miosis and adrenaline infusion may be a useful supportive treatment.

  14. Antiarrhythmic properties of a rapid delayed-rectifier current activator in rabbit models of acquired long QT syndrome

    DEFF Research Database (Denmark)

    Diness, Thomas G; Yeh, Yung-Hsin; Qi, Xiao Yan;


    effect of a novel compound (NS1643) that activates the rapid delayed-rectifier K+ current, I(Kr), in two rabbit models of acquired LQTS. METHODS AND RESULTS: We used two clinically relevant in vivo rabbit models of TdP in which we infused NS1643 or vehicle: (i) three-week atrioventricular block...... with ventricular bradypacing; (ii) dofetilide-induced I(Kr) inhibition in methoxamine-sensitized rabbits. In addition, we studied effects on ionic currents in cardiomyocytes with I(Kr) suppressed by bradycardia remodelling or dofetilide exposure. Bradypaced rabbits developed QT interval prolongation, spontaneous...... ventricular ectopy, and TdP. Infusion of NS1643 completely suppressed arrhythmic activity and shortened the QT interval; vehicle had no effect. NS1643 also suppressed ventricular tachyarrhythmias caused by infusion of dofetilide to methoxamine-sensitized rabbits, and reversed dofetilide-induced QT...

  15. Persistent pulmonary consolidation treated with intrapulmonary percussive ventilation: a preliminary report. (United States)

    Birnkrant, D J; Pope, J F; Lewarski, J; Stegmaier, J; Besunder, J B


    Intrapulmonary percussive ventilation (IPV) is a novel form of chest physiotherapy delivered by a percussive pneumatic device (IPV, Percussionaire, Sand Point, ID). There are few published reports about the use of IPV for diseases other than cystic fibrosis. We report our experience with three pediatric patients and one adult patient with persistent pulmonary consolidation refractory to conventional therapies. Three of the four patients had neuromuscular disease; one patient had segmental atelectasis due to aspiration. Three of the four patients showed clinical and radiographic improvement within 48 hours of starting IPV. The fourth patient experienced brief episodes of third-degree atrioventricular block, hypoxemia, and bradycardia during two IPV treatments. IPV was safely restarted and he slowly improved. We conclude that while IPV requires further clinical evaluation, it appears to be a safe and effective therapy for selected patients. However, close observation is essential during and after IPV treatments, especially in patients who have difficulty mobilizing or expectorating sputum.

  16. Posterior Uterine Rupture Causing Fetal Expulsion into the Abdominal Cavity: A Rare Case of Neonatal Survival

    Directory of Open Access Journals (Sweden)

    K. Navaratnam


    Full Text Available Introduction. Uterine rupture is a potentially catastrophic complication of vaginal birth after caesarean section. We describe the sixth case of posterior uterine rupture, with intact lower segment scar, and the first neonatal survival after expulsion into the abdominal cavity with posterior rupture. Case Presentation. A multiparous woman underwent prostaglandin induction of labour for postmaturity, after one previous caesarean section. Emergency caesarean section for bradycardia revealed a complete posterior uterine rupture, with fetal and placental expulsion. Upon delivery, the baby required inflation breaths only. The patient required a subtotal hysterectomy but returned home on day 5 postnatally with her healthy baby. Discussion. Vaginal birth after caesarean section constitutes a trial of labour, and the obstetrician must be reactive to labour events. Posterior uterine rupture is extremely rare and may occur without conventional signs. Good maternal and fetal outcome is possible with a prompt, coordinated team response.

  17. Cardiorespiratory responses and reduced apneic time to cold-water face immersion after high intensity exercise. (United States)

    Konstantinidou, Sylvia; Soultanakis, Helen


    Apnea after exercise may evoke a neurally mediated conflict that may affect apneic time and create a cardiovascular strain. The physiological responses, induced by apnea with face immersion in cold water (10 °C), after a 3-min exercise bout, at 85% of VO2max,were examined in 10 swimmers. A pre-selected 40-s apnea, completed after rest (AAR), could not be met after exercise (AAE), and was terminated with an agonal gasp reflex, and a reduction of apneic time, by 75%. Bradycardia was evident with immersion after both, 40-s of AAR and after AAE (Pexercise without apnea was not equally elevated. The activation of neurally opposing functions as those elicited by the diving reflex after high intensity exercise may create an autonomic conflict possibly related to oxygen-conserving reflexes stimulated by the trigeminal nerve, and those elicited by exercise.

  18. Effects of nuclei ambiguus and dorsal motor nuclei of vagus on gastric H+ and HCO3- secretion in rats

    Institute of Scientific and Technical Information of China (English)

    Xue-Ying Zhang; Hong-Bin Ai; Xi-Yun Cui


    AIM: To determine the effects of electrical stimulation of nucleus ambiguus (NA) and dorsal motor nuclei of vagus (DMV) on gastric acid and bicarbonate secretion in rats.METHODS: NA and DMV in rats were electrically stimulated. Pylorus ligation or esophagus perfusion was used to collect the gastric secretion. The titratable H+ quantum, H+ concentration, HCO3- secretion quantum were measured.RESULTS: Electrical stimulation of NA had no effects on the volume of gastric juice, titratable acidity and acid concentration, but elicited a pronounced increase in the total bicarbonate. However, electrical stimulation of DMV significantly increased the titratable acidity, the volume of gastric juice and the acid concentration. Similarly,electrical stimulation of either NA or DMV decreased the respiratory frequency and sinus bradycardia.CONCLUSION: NA in rats can not control the secretion of gastric acid but the secretion of bicarbonate in gastric juice, while DMV controls the secretion of gastric acid.

  19. EEG Suppression Associated with Apneic Episodes in a Neonate

    Directory of Open Access Journals (Sweden)

    Evonne Low


    Full Text Available We describe the EEG findings from an ex-preterm neonate at term equivalent age who presented with intermittent but prolonged apneic episodes which were presumed to be seizures. A total of 8 apneic episodes were captured (duration 23–376 seconds during EEG monitoring. The baseline EEG activity was appropriate for corrected gestational age and no electrographic seizure activity was recorded. The average baseline heart rate was 168 beats per minute (bpm and the baseline oxygen saturation level was in the mid-nineties. Periods of complete EEG suppression lasting 68 and 179 seconds, respectively, were recorded during 2 of these 8 apneic episodes. Both episodes were accompanied by bradycardia less than 70 bpm and oxygen saturation levels of less than 20%. Short but severe episodes of apnea can cause complete EEG suppression in the neonate.

  20. Neurally mediated syncope presenting with paroxysmal positional vertigo and tinnitus. (United States)

    Goto, Fumiyuki; Tsutsumi, Tomoko; Nakamura, Iwao; Ogawa, Kaoru


    A 72-year-old man with positional vertigo and tinnitus was referred to us. He did not want to perform provoking test except once due to his fear. No positional nystagmus was provoked. He found that his attacks usually occurred when he lay on his right ear. From his clinical history, benign paroxysmal positional vertigo was suspected. Conventional pharmacotherapy as well as non-specific physical therapy did not have significant effect. His feeling of positional vertigo with pyrosis was actually presyncope. We suspected cardiovascular disorders, and referred him to a cardiologist. Portable cardiogram monitoring revealed paroxysmal bradycardia. He was diagnosed with neurally mediated syncope, and a pacemaker was implanted. His paroxysmal dizziness soon disappeared. It is important to study the clinical history of the patients in detail, as they are not always able to accurately explain their symptoms. We should carefully rule out cardiovascular disorders, especially when we see the patients with suspected BPPV without the characteristic positional nystagmus.

  1. A 'one in a million' case of pulsating thoracoabdominal mass.

    LENUS (Irish Health Repository)

    Tan, Lay Ong


    Ectopia cordis is a rare congenital malformation in which the heart is located partially or totally outside the thoracic cavity. It comprises 0.1% of congenital heart diseases. The authors present a case of a male baby born at term by emergency caesarean section due to prolonged fetal bradycardia, who was noted to have a large pulsating mass in the thoracoabdominal area. In view of lower thoracolumbar abdominal defect, ectopic placement of the umbilicus, deficiency of the diaphragmatic pericardium, deficiency of anterior diaphragm and intracardiac abnormalities, a diagnosis of ectopia cordis-Pentalogy of Cantrell was made. He was transferred to a tertiary centre and required oxygen supplement initially. He was sent home after 1 week, on propanolol, with weekly oxygen saturation checks. He is awaiting further surgical intervention pending the required weight gain.

  2. Ogilvie′s syndrome in a case of myxedema coma

    Directory of Open Access Journals (Sweden)

    Uday Yanamandra


    Full Text Available Ogilvie′s syndrome [acute colonic pseudo-obstruction (ACPO] presents as massive colonic dilatation without a mechanical cause, usually in critically ill patients due to imbalanced sympathetic and parasympathetic activity. The initial therapy remains conservative with supportive measures (correction of metabolic, infectious or pharmacologic factors followed by neostigmine and decompressive colonoscopy. Surgery is reserved for patients with clinical deterioration or with evidence of colonic ischemia or perforation. A 60-year-old lady presented with fever, altered sensorium, obstipation, bradycardia and abdominal distension. Investigation revealed hyponatremia and acute colonic pseudo-obstruction. Supportive measures and decompressive colonoscopy were not of great benefit. Thyroid profile was suggestive of primary hypothyroidism. Colonic motility was restored only on starting thyroxin. The case is illustrative of the need to consider hypothyroidism, a common endocrine disorder, in the differential diagnosis of Ogilvie′s.

  3. Positive predictive value of cardiovascular diagnoses in the Danish National Patient Registry

    DEFF Research Database (Denmark)

    Sundbøll, Jens; Adelborg, Kasper; Munch, Troels;


    medical record review as the reference standard, we examined the PPV for cardiovascular diagnoses in the DNPR, coded according to the International Classification of Diseases, 10th Revision. RESULTS: A total of 2153 medical records (97% of the total sample) were available for review. The PPVs ranged from......OBJECTIVE: The majority of cardiovascular diagnoses in the Danish National Patient Registry (DNPR) remain to be validated despite extensive use in epidemiological research. We therefore examined the positive predictive value (PPV) of cardiovascular diagnoses in the DNPR. DESIGN: Population...... pectoris, pulmonary hypertension, bradycardia, ventricular tachycardia/fibrillation, endocarditis, cardiac tumours, first-time venous thromboembolism and between 70% and 80% for first-time and recurrent admission due to heart failure, first-time dilated cardiomyopathy, restrictive cardiomyopathy...

  4. Congenital echovirus 21 infection causing fulminant hepatitis in a neonate. (United States)

    Pedrosa, Cristina; Lage, Maria João; Virella, Daniel


    Enteroviral infection in pregnancy is common and there is growing evidence relating it to congenital anomalies and neonatal mortality. Neonatal disease may range from unapparent infection to overwhelming systemic illness. Passively acquired maternal serotype specific antibodies determine the severity of the disease in the newborn. A fatal case of congenital echovirus 21 infection, confirmed by PCR in the patient's blood and positive culture of the mother's stools, is reported. A sibling had symptoms of respiratory tract infection and their mother had fever, which prompted iatrogenic delivery that same day. The newborn presented with bradycardia and hypotonia in the first minutes of life and later developed respiratory distress, disseminated intravascular coagulopathy, fulminant hepatitis, acute renal failure and necrotising enterocolitis. Death occurred on the 8 day of life. This case highlights the potential severity of Enteroviral infection in the newborn. Since only supportive treatment is available, prevention is paramount.

  5. A prospective randomized double blind study to compare dexmedetomidine and midazolam in ear nose and throat surgery for monitored anesthesia care

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    Manmath A. Delmade


    Results: The drop in HR and MBP from pre-operative value was observed at various intervals during the surgery and also in the recovery in both the groups but it was significant in group D (P<0.005. Patient satisfaction was significantly better with dexmedetomidine compared to midazolam (p=0.0001. There were no side effects in both of the groups except for bradycardia in group D which was reversed easily with injection atropine. Conclusions: Dexmedetomidine promises to be a suitable alternative to midazolam with added advantage of better patient satisfaction and faster recovery, but with close monitoring of hemodynamics. [Int J Res Med Sci 2016; 4(8.000: 3159-3163

  6. Acute Pulmonary Thromboembolism Presenting As Complete Heart Block - A Rare Presentation

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    Vikash Goyal


    Full Text Available Acute pulmonary thromboembolism (PTE is a life threatening condition which requires early diagnosis and management. Electrocardiogram (ECG is helpful for suspecting the disease. The various ECG changes are sinus tachycardia, P pulmonale, Right bundle branch block (RBBB -incomplete or complete, axis shift, S1Q3T3, T wave inversion, and ST-segment depression in leads V1-4, aVF, and Lead III, supra ventricular tachycardia, low voltage QRS complex in limb leads. In addition, sinus bradycardia and complete heart block (CHB can be seen. CHB has been reported as an exceptionally rare manifestation of acute PTE. Here, we are reporting a case of 66 year old male presented with CHB with acute pulmonary thromboembolism, who reverted to sinus rhythm after thrombolysis.

  7. Vasovagal reflex emergency caused by Riedel's thyroiditis: A case report and review of the literature. (United States)

    Cai, Wei; Kang, Hua; Hai, Tao


    Riedel's thyroiditis is a rare type of chronic thyroiditis, associated with fibroinflammatory process and invasion into surrounding tissues, leading to compressive symptoms. A 45-year-old man had a left thyroid mass, presenting with hypotension and bradycardia many times. He was diagnosed with vasovagal reflex caused by cervical vessel compression due to a thyroid lesion. We performed the emergency operation, and most of the left thyroid was removed to relieve the compression on cervical vessels. The result of pathology proved to be Riedel's thyroiditis. The vasovagal reflex did not occur any more during the 28-month follow up, except on the 3(rd) day after the surgery. Six months after the thyroidectomy, the patient was found to have retroperitoneal fibrosis, diagnosed by biopsy during a laparotomy for biliary disease. Riedel's thyroiditis can lead to a vasovagal episode and might not be a primary thyroid disease but rather a manifestation of the systemic disorder, multifocal fibrosclerosis.

  8. Life-threatening hyperkalemia: a potentially lethal drug combination. (United States)

    Juvet, Tristan; Gourineni, Venkata C; Ravi, Sandeep; Zarich, Stuart W


    Hyperkalemia is commonly seen in the elderly and is occasionally fatal. Inadvertently combining potassium sparing medications can result in profound hyperkalemia which may result in cardiac dysrhythmias, especially in the setting of chronic kidney disease. An 85 year-old woman on a drug regimen of sotalol, valsartan, spironolactone, and trimethoprim-sulfamethoxazole presented to the emergency department with hypotension and bradycardia. Presumptive treatment for hyperkalemia was started based on her initial electrocardiogram. This diagnosis was later confirmed with a serum potassium value of 10.1 mmol/L. Following pharmacologic treatment, emergency hemodialysis was performed and the patient subsequently recovered. It is known that several drug classes can cause hyperkalemia, with elderly patients at a higher risk of developing this side effect. It is believed that this was a major contributor to the degree of hyperkalemia seen in this patient.

  9. [Extra-adrenal pheochromocytoma discovered peroperatively]. (United States)

    Rabii, R; Idali, B; Joual, A; Sarf, I; Naciri, K; Hafiani, M; Bennani, S; Harti, A; El Mrini, M; Barrou, L; Benjelloun, S


    In this study, an uncommon case has been reported of an ectopic pheochromocytoma without the presence of any clinical symptoms. The radiological investigations showed a right retroperitoneal tumor without any kidney involvement. The diagnosis was established by biopsy and subsequent histological findings. In the course of surgery as the large tumor mass was being removed, tachycardia was observed which caused the resection to be performed as rapidly as possible. Once the tumor had been removed, bradycardia occurred, followed by cardiac arrest: although the latter was stabilized after cardiac massage, the patient died one hour after the operative field had been closed. In addition to this case report, the diagnosis, therapeutic strategy and prognosis regarding an ectopically located pheochromocytoma have been discussed.

  10. Apnea of prematurity

    Directory of Open Access Journals (Sweden)

    Piermichele Paolillo


    Full Text Available Apnea of prematurity (AOP is one of the most frequent pathologies in the Neonatal Intensive Care Unit, with an incidence inversely related to gestational age. Its etiology is often multi factorial and diagnosis of idiopathic forms requires exclusion of other underlying diseases. Despite being a self-limiting condition which regresses with the maturation of the newborn, possible long-term effects of recurring apneas and the degree of desaturation and bradycardia who may lead to abnormal neurological outcome are not yet clarified. Therefore AOP needs careful evaluation of its etiology and adequate therapy that can be both pharmacological and non-pharmacological. Proceedings of the 9th International Workshop on Neonatology · Cagliari (Italy · October 23rd-26th, 2013 · Learned lessons, changing practice and cutting-edge research

  11. Autonomic and electrocardiographic changes in cardioinhibitory syncope

    DEFF Research Database (Denmark)

    Mehlsen, Jesper; Kaijer, Michelle Nymann; Mehlsen, Anne-Birgitte


    Aims Cardioinhibitory syncope (CS) is a neurally mediated response causing bradycardia or asystole. This study reports on changes in blood pressure, heart rate variability (HRV), and ECG patterns before and after syncope with asystole. Methods and results Thirty-five patients with CS and a matched...... in four. Asystole was followed by sinus rhythm in four, junctional rhythm in 24, atrioventricular block in four, and atria[ fibrillation in three. The two groups did not differ with respect to supine heart rate, HRV or blood pressure. Prior to syncope, patients showed significant increases in total...... and tow-frequency HRV with reductions in high-frequency HRV and a progressive shortening of the PR-interval. Conclusion Syncope was preceded by marked accentuation of sympathetic tone with a sudden shift in heart rate control to vagal dominance. Asystole was accompanied by vagally induced, benign...

  12. Sedation with dexmedetomidine in the intensive care setting

    Directory of Open Access Journals (Sweden)

    Gerlach AT


    Full Text Available Anthony T Gerlach, Claire V Murphy The Ohio State University Medical Center, Ohio State University, Columbus, OH, USA Abstract: Dexmedetomidine is an α-2 agonist that produces sedation and analgesia without compromising the respiratory drive. Use of dexmedetomidine as a sedative in the critically ill is associated with fewer opioid requirements compared with propofol and a similar time at goal sedation compared with benzodiazepines. Dexmedetomidine may produce negative hemodynamic effects including lower mean heart rates and potentially more bradycardia than other sedatives used in the critically ill. Recent studies have demonstrated that dexmedetomidine is safe at higher dosages, but more studies are needed to determine whether the efficacy of dexmedetomidine is dose dependent. In addition, further research is required to define dexmedetomidine's role in the care of delirious critically ill patients, as many, but not all, studies have indicated favorable outcomes. Keywords: dexmedetomidine, sedation, critical care

  13. A ‘One in a million’ case of pulsating thoracoabdominal mass (United States)

    Tan, Lay Ong; Lim, Soo Yen; Sharif, Farhana


    Ectopia cordis is a rare congenital malformation in which the heart is located partially or totally outside the thoracic cavity. It comprises 0.1% of congenital heart diseases. The authors present a case of a male baby born at term by emergency caesarean section due to prolonged fetal bradycardia, who was noted to have a large pulsating mass in the thoracoabdominal area. In view of lower thoracolumbar abdominal defect, ectopic placement of the umbilicus, deficiency of the diaphragmatic pericardium, deficiency of anterior diaphragm and intracardiac abnormalities, a diagnosis of ectopia cordis—Pentalogy of Cantrell was made. He was transferred to a tertiary centre and required oxygen supplement initially. He was sent home after 1 week, on propanolol, with weekly oxygen saturation checks. He is awaiting further surgical intervention pending the required weight gain. PMID:23148397

  14. [Arrhythmia and sport]. (United States)

    Saoudi, N; Yaici, K; Zarkane, N; Darmon, J P; Rinaldi, J P; Brunner, P; Ricard, P; Mourou, M Y


    Sports arrhythmia has gained wide attention with the mediatization of the death of famous sports stars. Sport strongly modifies the structure of the heart with the development of left ventricular hypertrophy which may be difficult to differentiate from that due to doping. Intense training modifies also the resting electrocardiogram with appearance of signs of left ventricular hypertrophy whereas resting sinus bradycardia and atrioventricular conduction disturbances usually reverts upon exertion. Accordingly, arrhythmia may develop ranging from extrasystoles to atrial fibrillation and even sudden death. Recent data suggest that if benign arrhythmia may be the result of the sole intense training and are reversible, malignant ventricular arrhythmia and sudden death mostly occur in unknown structural heart disease. Hypertrophic cardiomyopathy is amongst the most frequent post mortem diagnosis in this situation. Doping is now present in many sports and further threatens the athlete in the safe practice of sport.

  15. [Congenital sick sinus syndrome in a healthy heart: case report]. (United States)

    Ben Ameur, Youssef; Hmam, Mohamed; Battikh, Kaïes; Mlika, Azmi; Terras, Mouna; Longo, Salma; Kraïem, Sondes; Slimane, Mohamed L


    Isolated congenital sick sinusal syndrome on non harmed heart is a rare affection. Its association with an atrio-ventricular block is exceptional. The authors report a case of a 19 year-old patient, with an early history of bradycardia, hospitalised for effort intolerance. His electrocardiogram reveals a high degree sino-atrial block replaced by a junctional rhythm at 30/mn. During Treadmill test, the sinusal acceleration is satisfactory and an effort atrio-ventricular block was present. He later had a definitive stimulation under DDDR. This report shows that the sinusal node, in the same way as the atrio-ventricular node may be injured by congenital dysimmunitary process. The coexistence of these two conductive troubles worsen the prognosis and should lead more often to the practice of definitive stimulation by the only mode DDDR.

  16. Tolazoline reversal of xylazine in bison (Bison bison): Mitigation of adverse effects (United States)

    Roffe, Thomas J.; Sweeney, Steven J.; Williams, Beth; Quist, Charlotte


    Tolazoline is a mixed alpha-1 and -2 adrenergic antagonist used to reverse the sedative, analgesic and muscle-relaxing effects of xylazine, a potent alpha adrenergic agonist. Tolazoline has been used in cattle and is superior to yohimbine, another alpha adrenergic antagonist, in this species. In white-tailed deer, tolazoline shortened recovery times and reversed xylazine-induced bradycardia, respiratory depression, and bloat following xylazine-ketamine anesthesia (Kreeger et al. 1986). We have used it for a number of years in moose without any detected adverse reactions. Caulkett et al. (2000) used tolazoline in wood bison to reverse the xylazine-induced effects of xylazine-tiletamine/zolazepam anesthesia and did not report any ill effects. However, the reported side effects of tolazoline in horses (species for which the drug was developed and is labeled) include abdominal discomfort, gastrointestinal hypermotility, diarrhea, tachycardia, ventricular dysrhythmia, hypertension and apprehensiveness.

  17. Risk assessment in poisoning with special reference to odollam and organophosphorous compounds

    Directory of Open Access Journals (Sweden)

    Meenu M. Tergestina


    Results: The most commonly ingested poisons were odollam (26% and organophosphorous compounds (22%. The overall mortality was 22%. Mortality was highest in organophosphorus compounds (38% and odollam (33% compared to other causes. Hyperkalemia, low systolic blood pressure, consumption of poison in powder or paste form, delayed presentation, bradycardia and extensive chest signs correlated with mortality in odollam and organophosphorous compound poisoning. Conclusions: Poisoning with odollam or organophosphorous compounds is an increasingly common life threatening condition. Markers of mortality identified in this study were incorporated into a simple scale for assessment of risk, namely the PoPPER scale: potassium level >5.5 mE/L, systolic blood pressure <90 mmHg, paste/powder form of poison ingestion, extremely late presentation, rate of QRS <40/min or impending respiratory paralysis. [Int J Res Med Sci 2016; 4(8.000: 3172-3175

  18. [A case report of right-sided cardiac and pulmonary thromboembolism treated by emergent operation]. (United States)

    Asaoka, M; Sasaki, M; Masumoto, H; Kajiyama, M; Seki, A


    A forty-four-year-old man with a clinical diagnosis of diabetes melitus and severe obesity (height 170 cm, weight 108 kg) was admitted to the hospital on 12th January 1995 because of acute myocardial infarction, and on 21st January, he was referred to our hospital with sudden onset of shock, bradycardia, loss of consciousness in spite of having recovered well from myocardial infarction. The echocardiography and pulmonary arteriography revealed a pulmonary embolism and a tumor in the right atrium. Administration of tissue plasminogen activator (TPA) was not sufficiently effective. An emergency operation (pulmonary arteriotomy, right atriotomy, milking of bilateral lungs) with cardiopulmonary bypass revealed a massive consecutive thrombus, which occupied the right atrium, right ventricle and bilateral pulmonary artery. The postoperative course was uneventful.

  19. Combined Case of Blood-Injury-Injection Phobia and Social Phobia: Behavior Therapy Management and Effectiveness through Tilt Test

    Directory of Open Access Journals (Sweden)

    Fotini Ferenidou


    Full Text Available The efficacy of behavior therapy based mainly on real-life exposure situations as well as applied tension was examined for a combined case of blood-injury-injection (BII phobia and social anxiety disorder. Treatment involved 28 behavior therapy sessions, while applied tension technique was also described and practiced. The specific contribution of social skills techniques, fantasy, and real-life situations exposure was examined in a single case design. The subject was a 39-year-old male with anxiety symptoms when confronting an audience, as well as symptoms of the autonomic nervous system (bradycardia and syncope, which were better explained by BII. All self-report measures regarding fear, social phobia, and anxiety were reduced after behavior therapy and remained maintained at followup, while BII decreased further after applied tension techniques. The contribution of behavior therapy to the overall outcome of the case is considered significant for many reasons that are discussed in the pape.

  20. Amitraz, an underrecognized poison: A systematic review

    Directory of Open Access Journals (Sweden)

    Sahajal Dhooria


    Results: The original search yielded 239 articles, of which 52 articles described human cases. After following the inclusion and exclusion criteria, 32 studies describing 310 cases (151 females, 175 children of human poisoning with amitraz were included in this systematic review. The most commonly reported clinical features of amitraz poisoning were altered sensorium, miosis, hyperglycaemia, bradycardia, vomiting, respiratory failure, hypotension and hypothermia. Amitraz poisoning carried a good prognosis with only six reported deaths (case fatality rate, 1.9%. Nearly 20 and 11.9 per cent of the patients required mechanical ventilation and inotropic support, respectively. The role of decontamination methods, namely, gastric lavage and activated charcoal was unclear. Interpretation & conclusions: Our review shows that amitraz is an important agent for accidental or suicidal poisoning in both adults and children. It has a good prognosis with supportive management.

  1. Clinical Implication of Cough CPR in Cardiac Cath Lab

    Directory of Open Access Journals (Sweden)

    Monish S Rau


    Full Text Available A 60 year-old-male with inferoposterior ST-elevation myocardial infarction (STEMI was shifted to cardiac cath lab for primary percutaneous coronary intervention (PCI. Coronary angiography revealed right coronary artery (RCA dominance with complete occlusion of the RCA in mid vessel. During angioplasty, the patient developed reperfusion induced Bezold Jarisch Reflex (BJR with profound bradycardia along with decrease in systolic pressure. The patient was asked to cough. The use of cough-CPR maintained the consciousness as the patient was getting syncopal. This report focuses on BJR and cough-CPR specific to interventional cardiology practice within the catheterization laboratory. Awareness of the fact that BJR may develop due to successful restoration of flow which can be managed with cough CPR, atropine and fluids can avoid the administration of vasoconstrictors.

  2. Levosimendan as treatment option in severe verapamil intoxication: a case report and review of the literature. (United States)

    Osthoff, Mirjam; Bernsmeier, Christine; Marsch, Stephan C; Hunziker, Patrick R


    Cardiovascular shock due to verapamil intoxication is often refractory to standard resuscitation methods. Recommended therapy includes prevention of further absorption of the drug, inotropic therapy, calcium gluconate, and hyperinsulinemia/euglycemia therapy. Often further measures are needed such as ventricular pacing or mechanical circulatory support. Still, mortality remains high. Levosimendan, an inotropic agent, that enhances myofilament response to calcium, increases myocardial contraction and could therefore be beneficial in verapamil intoxication. Here, we report the case of a 60-year-old patient with clinically severe verapamil poisoning who presented with shock, bradycardia, and sopor. Standard therapy including high-dose inotropes failed to ameliorate the signs of intoxication. But additional therapy with levosimendan led to rapid improvement. Based on this observation, the literature is reviewed focusing on utilization of levosimendan in the treatment of calcium channel blocker overdose. We suggest to consider levosimendan as additional treatment option in patients with cardiovascular shock due to verapamil intoxication that are refractory to standard management.

  3. Vagal reflex stimulation complicating retrieval of an unusual foreign body from the laryngotracheal lumen: Case report

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    H.K. Omokanye


    Full Text Available Foreign body impaction in the aero digestive tract is a life-threatening emergency, particularly in the paediatric age group. Removal under general anaesthesia poses both surgical and anaesthetic challenges and this may rarely result in mortality. We report a case of a 4 year old boy with an unusual foreign body (FB impacted in the laryngotracheal causing difficult intubation and precluding tracheostomy with attendant vasovagal reflex stimulation and cardiac arrest. Clinical presentation and radiological evaluation of the patient were highlighted with a review of pertinent literature. We conclude that dis-impacting a foreign body in the trachea could potentiate bradycardia and cardiac arrest; co-existing hypercarbia and/or sepsis increase the risk and worsen the prognosis.

  4. An autopsy case of vagus nerve stimulation following acupuncture. (United States)

    Watanabe, Mayumi; Unuma, Kana; Fujii, Yusuke; Noritake, Kanako; Uemura, Koichi


    Acupuncture is one of the most popular oriental medical techniques in China, Korea and Japan. This technique is also popular as alternative therapy in the Western World. Serious adverse events are rare following acupuncture, and fatal cases have been rarely reported. A male in his late forties died right after acupuncture treatment. A medico-legal autopsy disclosed severe haemorrhaging around the right vagus nerve in the neck. Other organs and laboratory data showed no significant findings. Thus, it was determined that the man could have died from severe vagal bradycardia and/or arrhythmia resulting from vagus nerve stimulation following acupuncture. To the best of our knowledge, this is the first report of a death due to vagus nerve injury after acupuncture.

  5. Central and Peripheral GABAA Receptor Regulation of the Heart Rate Depends on the Conscious State of the Animal

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    Bo Hjorth Bentzen


    Full Text Available Intuitively one might expect that activation of GABAergic inhibitory neurons results in bradycardia. In conscious animals the opposite effect is however observed. GABAergic neurons in nucleus ambiguus hold the ability to control the activity of the parasympathetic vagus nerve that innervates the heart. Upon GABA activation the vagus nerve will be inhibited leaving less parasympathetic impact on the heart. The picture is however blurred in the presence of anaesthesia where both the concentration and type of anaesthetics can result in different effects on the cardiovascular system. This paper reviews cardiovascular outcomes of GABA activation and includes own experiments on anaesthetized animals and isolated hearts. In conclusion, the impact of changes in GABAergic input is very difficult to predict in these settings, emphasizing the need for experiments performed in conscious animals when aiming at determining the cardiovascular effects of compounds acting on GABAergic neurons.

  6. Quantitative EEG and Current Source Density Analysis of Combined Antiepileptic Drugs and Dopaminergic Agents in Genetic Epilepsy: Two Case Studies. (United States)

    Emory, Hamlin; Wells, Christopher; Mizrahi, Neptune


    Two adolescent females with absence epilepsy were classified, one as attention deficit and the other as bipolar disorder. Physical and cognitive exams identified hypotension, bradycardia, and cognitive dysfunction. Their initial electroencephalograms (EEGs) were considered slightly slow, but within normal limits. Quantitative EEG (QEEG) data included relative theta excess and low alpha mean frequencies. A combined treatment of antiepileptic drugs with a catecholamine agonist/reuptake inhibitor was sequentially used. Both patients' physical and cognitive functions improved and they have remained seizure free. The clinical outcomes were correlated with statistically significant changes in QEEG measures toward normal Z-scores in both anterior and posterior regions. In addition, low resolution electromagnetic tomography (LORETA) Z-scored source correlation analyses of the initial and treated QEEG data showed normalized patterns, supporting a neuroanatomic resolution. This study presents preliminary evidence for a neurophysiologic approach to patients with absence epilepsy and comorbid disorders and may provide a method for further research.

  7. Requirement of Emergency Hemodialysis in a Peritoneal Dialysis Patient; Laxative Induced Hypermagnesemia: A Case Report

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    Mustafa YAPRAK


    Full Text Available Hypermagnesemia is rarely seen in peritoneal dialysis (PD patients because PD can lower the plasma magnesium (Mg concentration effectively. In this report, a continuous ambulatory peritoneal dialysis (CAPD patient with life-threatening hypermagnesemia treated by hemodialysis (HD is presented. A 52-year-old male patient on PD treatment was admitted to our clinic with complaints of fatigue and muscle weakness. Decrease in deep tendon reflexes (DTR, decrease in muscle strength at bilateral upper and lower extremities, and increased level of magnesium (7.7 mg/dl were detected. Bradycardia, prolongation of the P-R interval, and an increase in Q-T interval were found on the electrocardiography. HD was performed two times. After HD, all the signs and symptoms of the patient improved. HD is a dialysis modality that should be preferred in the treatment of symptomatic patients with hypermagnesemia, because of providing more rapid clearance of Mg.

  8. Modulators of the Sphingosine 1-phosphate receptor 1. (United States)

    Urbano, Mariangela; Guerrero, Miguel; Rosen, Hugh; Roberts, Edward


    The Sphingosine 1-phosphate receptor (S1P-R) signaling system has proven to be of biological and medical importance in autoimmune settings. S1P1-R is a validated drug target for multiple sclerosis (MS) for which FTY720 (Fingolimod), a S1P1,3-5-R pan-agonist, was recently approved as the first orally active drug for the treatment of relapsing-remitting MS. Transient bradycardia and long half-life are the FTY720 critical pitfalls. This review provides the latest advances on next-generation S1P1-R modulators from 2012 up to date, with an overview of the chemical structures, structure-activity relationships, and relevant biological and clinical properties.


    Directory of Open Access Journals (Sweden)

    Bhise Dhondiba


    Full Text Available Patients with obstructive sleep apnea (OSA have various Comorbidities like cardiovascular, cerebrovascular diseases and metabolic disorders. There is an association between pulmonary hypertension and obstructive sleep apnea. Obstructive sleep apnea is associated with nocturnal arterial oxygen desaturation. During apnea the increa sed vagal tone induces hypoxia and by mechanical effects of obstructive sleep apnea associated with intrathoracic pressure swings leads to bradycardia and acute increase in pulmonary artery pressure. Patients with coronary artery disease may develop myocar dial ischemia during apneas. Post - tuberculosis patients can lead to pulmonary sequelae that are characterized by impairments in the bronchial and parenchymal structure. The structural changes include bronchovascular distortions, bronchiectasis, emphysema a nd fibrosis. This leads to greater ventilation perfusion (V/Q mismatch and hypoxia.

  10. A Case of Torsion of Gravid Uterus Caused by Leiomyoma

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    Gururaj Deshpande


    Full Text Available Uterine torsion during pregnancy is only sporadically reported in the literature. Here we present a case of leiomyoma causing uterine torsion in pregnancy and review the literature on etiology, diagnosis, and management. A 25-years-old primigravida with leiomyoma complicating pregnancy was admitted in our hospital with abdominal pain and uterine tenderness. She underwent emergency LSCS (lower segment cesarean section for fetal bradycardia. Intraoperatively, the uterus was rotated 180 degrees left to right. Inadvertent incision on the posterior wall was avoided by proper delineation of anatomy. Torsion was corrected by exteriorization of leiomyoma and uterus, and lower segment cesarean was carried out safely. Prompt recognition and management of this condition is necessary for better maternal and fetal outcome.

  11. Dermatological allergic reaction caused by dexmedetomidine in a patient administered intravenous regional anesthesia with dexmedetomidine–lignocaine combination

    Directory of Open Access Journals (Sweden)

    Ketaki Marodkar


    Full Text Available Dexmedetomidine a highly selective α2 agonist has become a frequently used drug in anesthesiologists’s armamentarium due to its sedative, anxiolytic, analgesic, neuroprotective and anesthetic sparing effects and a favorable side effect profile. Dexmedetomidine–lignocaine combination has been used recently to provide Bier’s block and was shown to improve quality of anesthesia, to reduce tourniquet pain and to reduce postoperative anesthetic requirement in patients undergoing forearm or hand surgeries. Hypotension and bradycardia are the commonly seen side effects. Only one case of dexmedetomidine skin allergy has been reported till date in literature. We present a case of dermatological allergy to dexmedetomidine, in a patient administered Bier’s block with dexmedetomidine–lignocaine combination for implant removal surgery of forearm.

  12. Prolonged QT interval in a man with anorexia nervosa (United States)

    Macías-Robles, María Dolores; Perez-Clemente, Ana María; Maciá-Bobes, Carmen; Alvarez-Rueda, María Asunción; Pozo-Nuevo, Sergio


    Anorexia nervosa is an eating disorder characterized by the avoidance of food intake, which usually leads to a weight loss. Cardiac co-morbility is common and we can find sometimes a mass loss from the left ventricle, which can be seen by echocardiography. But the commonest complications are rhythm variations, typically bradycardia with a prolonged QT interval in up to a 40% of the cases, which altogether elevates ventricular tachycardia and sudden death risk. We present the case of a male who was diagnosed with anorexia nervosa and developed asthenia, a long QT interval and also a severe both hypokalaemia and hypomagnesaemia. We intend to discuss the pathogenic paths as well as prophylactic and therapeutic measures to this potentially-lethal pathology. PMID:19646241

  13. Haemostasis with fibrin glue injection into the pericardial space for right ventricular perforation caused by an iatrogenic procedural complication. (United States)

    Arai, Hirofumi; Miyamoto, Takamichi; Hara, Nobuhiro; Obayashi, Tohru


    An 89-year-old woman with severe aortic valve stenosis and bradycardia presented with circulatory shock due to cardiac tamponade. We performed pericardiocentesis, and then diagnosed right ventricular perforation by echocardiography with microcavitation contrast medium just before inserting a drainage tube. We then inserted the drainage tube in the appropriate position and withdrew blood-filled fluid. The patient was haemodynamically stabilised, but haemorrhage from the perforation site continued for a few days. We injected fibrin glue into the pericardial space through the drainage tube and achieved haemostasis. Thus, we avoided surgery to close the perforation in this high-risk patient. There was no recurrence of haemorrhage. She subsequently had elective aortic valve replacement at another hospital. No adhesions in the pericardial space were seen during surgery.

  14. Torsades de pointes with methadone. (United States)


    (1) Methadone is an opiate used for replacement therapy of opiate addiction that causes dose-dependent QT prolongation. (2) Severe ventricular arrhythmias such as torsades de pointes have been reported, usually in patients on high doses (100 mg to 400 mg/day). (3) Methadone has a long plasma elimination half-life, and this poses a risk of accumulation. Accumulation is especially problematic when the dose is increased too rapidly. Combining methadone with a CYP 3A4 inhibitor increases the risk of torsades de pointes, as methadone is metabolised by this enzyme system. (4) Factors potentially predisposing patients to torsades de pointes must be analysed in each case; these include preexisting bradycardia, congenital QT prolongation, hypokalemia, and concomitant use of other drugs inducing QT prolongation. (5) This adverse effect has also been reported with levacetylmethadol (another opiate) and with heroin. It does not seem to occur with buprenorphine.

  15. Haemodynamic collapse in a patient with acute inferior myocardial infarction and concomitant traumatic acute spinal cord injury. (United States)

    Kumagai, Naoto; Dohi, Kaoru; Tanigawa, Takashi; Ito, Masaaki


    A 71-year-old man suddenly collapsed and went into cardiopulmonary arrest. The cardiopulmonary resuscitation attempt succeeded in restoration of spontaneous circulation. The initial 12-lead electrocardiogram showed inferior acute myocardial infarction (AMI). The patient was initially diagnosed as having cardiogenic shock associated with inferior AMI. In spite of early coronary revascularisation, bradycardia and hypotension were sustained. After termination of sedation and extubation, he was found to have a quadriplegia and diagnosed with a cervical spinal cord injury (SCI). Therefore, the patient was finally diagnosed with neurogenic shock caused by acute cervical SCI due to the traumatic injury preceded by loss of consciousness complicating inferior AMI. We should recognise that SCI has unique haemodynamic features that mimic those associated with inferior AMI, but requires very different treatment.

  16. Pacemaker patients’ perspective and experiences in a pacemaker outpatient clinic in relation to test intervals of the pacemaker

    DEFF Research Database (Denmark)

    Lauberg, Astrid; Hansen, Tina; Pedersen, Trine Pernille Dahl

    the pacemaker and psychological reactions. Patients with pacemakers older than 3 months lacked communication with fellowmen. Conclusion The patients express receiving competent and professional treatment when visiting the outpatient clinic, there seems to be a discrepancy between the long test intervals......In and out in 15 minutes! Shorttime nursing in an outpatient clinic Pacemaker patients’ perspective and experiences in a pacemaker outpatient clinic in relation to test intervals of the pacemaker. Background Pacemaker implantation is a highly documented treatment for patients with bradycardia...... an evident decline in quality of life regarding psychological and social aspects 6 month after the implantation in terms of cognitive function, work ability, and sexual activity. Mlynarski et al (2009) have found correlations between pacemaker implantation and anxiety and depression. Aim The aim...

  17. Prevalence of family history in patients with reflex syncope

    DEFF Research Database (Denmark)

    Holmegard, Haya N; Benn, Marianne; Kaijer, Michelle Nymann;


    Reflex syncope is defined by a rapid transient loss of consciousness caused by global cerebral hypoperfusion resulting from vasodilatation and/or bradycardia attributable to inappropriate cardiovascular reflexes. A hereditary component has been suggested, but prevalence of family history may differ...... among subtypes of reflex syncope, as these have different autonomic responses and pathogeneses may be diverse. The present study aimed to assess the prevalence of a positive family history of syncope and cardiovascular characteristics in patients with cardioinhibitory and vasodepressor reflex syncope....... Patients (n=74) were classified into subtypes of reflex syncope - cardioinhibition/asystole (Vasovagal Syncope International Study subtypes II-B [VASIS II-B], n=38) or vasodepressor (VASIS III, n=36) - using the head-up tilt test. Family history was obtained by questionnaires supplemented by interview...

  18. Respiration and heart rate in exercising land crabs. (United States)

    Herreid, C F; Lee, L W; Shah, G M


    Land Crabs, Cardisoma guanhumi, were fitted with respiratory masks and E.C.G. electrodes and run for 10 or 20 min on a treadmill at speeds of 150 and 300 cm/min. Aerobic metabolism increased linearly with the speed of locomotion. The recovery period was characterized by a large oxygen debt. The primary respiratory adjustment to exercise was an increased ventilation volume; only a minor increase in oxygen extraction occurred. The respiratory exchange ratio increased during exercise and during recovery, presumably correlated with a metabolic acidosis. These results are similar to data collected for exercising vertebrates and the net cost of locomotion of crabs appears similar to quadrupeds. However, the heart rate in exercising crabs changed in an unexpected way: during moderate exercise no change was noted, but during heavy exercise a bradycardia developed. The reduction in rate resulted from an increase in interbeat interval and frequent pauses in the heart beat.

  19. Regulation of blood pressure in the land crab Cardisoma guanhumi. (United States)

    Wilkens, J L; Young, R E


    We examined the cardiovascular responses to acute and chronic changes in blood volume (BV) in the land crab Cardisoma guanhumi. Acute reduction in BV caused an increase in activity in the dorsoventral muscles (DVMs) and to a lesser extent in the epimeral attractor muscles (EAMs). Contraction of the DVMs and EAMs will decrease the volume of the dorsal sinus and the thorax as a whole, respectively. BV reduction also caused bradycardia with frequent periods of cardiac arrest. There was a small drop in hemolymph pressure. BV expansion had the reciprocal effect on DVM and EAM activity but had no effect on heart rate (fH). After the cardioregulatory nerves were cut, acute hypovolemia had no effect on fH but still caused a moderate increase in DVM activity. After dehydration-induced BV reduction, DVM activity increased, whereas hemolymph pressure, fH, and EAM activity were maintained close to control levels.

  20. 癫痫发作期心搏停止研究进展

    Institute of Scientific and Technical Information of China (English)

    王滨; 王乃东; 王其新


    @@ 癫痫患者痫性发作过程中发生的心搏停止称为癫痫发作期心搏停止(ictal asystole,IA),是癫痫发作期心动过缓(ictal bradycardia,IB)的特殊表现.作为一种少见但危及患者生命的癫痫并发症,可能与癫痫猝死(sudden unexplaineddeath in epilepsy,SUDEP)及癫痫发作相关外伤的发生有关,主要见于局灶性癫痫的发作过程中[1].我们对IA的相关文献进行系统综述,旨在提高对该现象的认识.

  1. Unforeseen Intra-operative Hyperkalemia in a well Dialyzed Patient during Renal Transplantation

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    Gautam P


    Full Text Available Renal excretion and cellular uptake of potassium play key roles in the body′s defense mechanism against hyperkalemia. Intra-operative hyperkalemia is an uncommon life-threatening complication during elective renal transplant surgery. We report herewith a non-insulin dependent diabetic kidney transplant recipient with prolonged pre-operative fasting, in whom, despite pre-operative hemodialysis, unforeseen high serum potassium level suddenly presented as wide-complex bradycardia during the surgery. The patient responded well to medical therapy of the hyperkalemia and the surgery was completed uneventfully. It is difficult to single out the exact cause of hyperkalemia in our patient. Prolonged pre-operative fasting for about nine hours, associated with insulinopenia and hyperglycemia, in the presence of β-blockade and metabolic acidosis, have probably collectively resulted in efflux of potassium from intra-cellular stores. This potentially catastrophic complication should be remembered in diabetic patients undergoing any type of surgery.

  2. Cardiac Disorder in an Iranian Child With Hepatitis A Virus

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    Full Text Available Introduction Hepatitis A is one of the most common types of viral hepatitis among children worldwide. Many infected individuals, especially younger children, are asymptomatic. It is usually transmitted by food or water contaminated with infected feces. Extra-hepatic manifestations of acute hepatitis A virus (HAV are very rare. Case Presentation We present a 14-year-old girl who was referred to our hospital due to jaundice, abdominal pain, weakness, and lethargy. After laboratory testing, HAV was confirmed in the patient. However, she had significant bradycardia with hypotension, which is very rare in HAV infection. Conclusions Hepatitis A causes an acute infection. The patients usually recover after a few weeks or months. Fulminant hepatitis can be observed in HAV infection but chronic infection does not exist. Extrahepatic complications and cardiac disorders are often reported in association with hepatitis C and B viruses, but they are very rare in HAV infections.

  3. Alkaloids with Cardiovascular Effects from the Marine-Derived Fungus Penicillium expansum Y32. (United States)

    Fan, Ya-Qin; Li, Pei-Hai; Chao, Ya-Xi; Chen, Hao; Du, Ning; He, Qiu-Xia; Liu, Ke-Chun


    Three new alkaloids (1, 4 and 8), together with nine known analogues (2, 3, 5-7, and 9-12), were isolated from the marine-derived fungus Penicillium expansum Y32. Their structures including the absolute configurations were elucidated by spectroscopic and Mosher's and Marfey's methods, along with quantum electronic circular dichroism (ECD) calculations. Each of the compounds was evaluated for cardiovascular effects in a live zebrafish model. All of the compounds showed a significant mitigative effect on bradycardia caused by astemizole (ASM) in the heart rate experiments. Compounds 4-6 and 8-12 exhibited potent vasculogenetic activity in vasculogenesis experiments. This is the first study to report that these types of compounds show cardiovascular effects in zebrafish. The results suggest that these compounds could be promising candidates for cardiovascular disease lead compounds.

  4. Alkaloids with Cardiovascular Effects from the Marine-Derived Fungus Penicillium expansum Y32

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    Ya-Qin Fan


    Full Text Available Three new alkaloids (1, 4 and 8, together with nine known analogues (2, 3, 5–7, and 9–12, were isolated from the marine-derived fungus Penicillium expansum Y32. Their structures including the absolute configurations were elucidated by spectroscopic and Mosher’s and Marfey’s methods, along with quantum electronic circular dichroism (ECD calculations. Each of the compounds was evaluated for cardiovascular effects in a live zebrafish model. All of the compounds showed a significant mitigative effect on bradycardia caused by astemizole (ASM in the heart rate experiments. Compounds 4–6 and 8–12 exhibited potent vasculogenetic activity in vasculogenesis experiments. This is the first study to report that these types of compounds show cardiovascular effects in zebrafish. The results suggest that these compounds could be promising candidates for cardiovascular disease lead compounds.

  5. T-wave morphology analysis of competitive athletes

    DEFF Research Database (Denmark)

    Hong, L; Andersen, Lars Juel; Graff, Claus;


    the characteristics of T-wave morphology features in athletes. METHODS: Eighty male elite athletes, consisting of 40 Tour de France cyclists (age 27±5years), 40 soccer players (age 26±6years) and 40 healthy men (age 27±5years) were included. RESULTS: Sinus bradycardia, left ventricular (LV) hypertrophy, incomplete......BACKGROUND: T-wave morphology has been shown to be more sensitive than QT and QTc interval to describe repolarization abnormalities. The electrocardiogram (ECG) performed in athletes may manifest abnormalities, including repolarization alterations. The aim of this study was to investigate...... right bundle branch block and early repolarization were documented in 25 %, 20%, 13% and 14% of athletes, respectively. ECG criteria for LV hypertrophy in 12-lead ECG were more common in cyclists (35%) than in soccer players (5%), P

  6. Oligodendroglioma in a French bulldog. (United States)

    Park, Chun-Ho


    A 5-year-old, male French bulldog with bradycardia, dyspnea, and decerebrate rigidity was necropsied. Macroscopic findings were restricted to the brain, and a single mass, 1.5 x 2.0 x 1.5 cm in size, was observed mainly at the right cingulum with prominently protruding into the dilated right lateral ventricle. The mass was grayish white in color, soft and gelatinous, but not clearly delineated. Microscopically, the mass consisted of diffuse proliferated neoplastic oligodendroglial cells characterized by small, round, and hyperchromatic nuclei with clear cytoplasm and the cells aggressively invaded into the adjacent parenchyma. Immunohistochemistry demonstrated that most of the neoplastic cells were positive for S-100 protein, vimentin, neuron specific enolase (NSE), and neurofilament protein (NFP). From these findings, the mass was diagnosed as oligodendroglioma.

  7. ECG Holter monitor with alert system and mobile application (United States)

    Teron, Abigail C.; Rivera, Pedro A.; Goenaga, Miguel A.


    This paper proposes a new approach on the Holter monitor by creating a portable Electrocardiogram (ECG) Holter monitor that will alert the user by detecting abnormal heart beats using a digital signal processing software. The alarm will be triggered when the patient experiences arrhythmias such as bradycardia and tachycardia. The equipment is simple, comfortable and small in size that fit in the hand. It can be used at any time and any moment by placing three leads to the person's chest which is connected to an electronic circuit. The ECG data will be transmitted via Bluetooth to the memory of a selected mobile phone using an application that will store the collected data for up to 24 hrs. The arrhythmia is identified by comparing the reference signals with the user's signal. The diagnostic results demonstrate that the ECG Holter monitor alerts the user when an arrhythmia is detected thru the Holter monitor and mobile application.

  8. The Safety of Autologous Peripheral Blood Stem Cell Transplantation by Intracoronory Infusion in Patients with Acute Myocardial Infarction

    Institute of Scientific and Technical Information of China (English)

    Zhang Ming; Li Zhanquan; Cui Lijie; Jin Yuanzhe; Yuan Long; Zhang Weiwei; Zhao Hongyuan


    Objectives Bone-marrow stem-cell transplantation has been shown to improve cardiac function in patients with acute myocardial infarction (AMI), but the safety of intracoronory infusion of autologous peripheral blood stem-cell (PBSCs) in patients with AMI is unknown. For this reason, we observe the feasibility and safety of PBSCs transplantation by intracoronory infusion in such patients. Methods 41 patients with AMI were allocated to receive granulocyte colony-stimulating factor (GCSF: Filgrastim, 300μg) with the dose of 300μg~600μg/day to mobilize the stem cell, and the duration of applying G-CSF was 5 days. On the sixth day, PBSCs were separated by Baxter CS 3000 blood cel 1 separator into suspend liquid 57 ml. Then the suspend liquid was infused into the infarct related artery (IRA)by occluding the over the wire balloon and infusing artery through balloon center lumen. In the process of the intracoronary infusion of PBSCs, the complications should be observed, which were arrhythmias including of bradycardia, sinus arrest or atrial ventricular block,premature ve. ntricular beats , ven~icular tachycardia,ventricular fibrillation; and hypotention, etc. Results There were total 10 cases with complications during the intracoronary infusion of PBSCs. The incidence of complications was 24.4% ( 10/41 ), including bradycardia was 2.4 % (1/41), sinus arrest or atrial ventricular block was 4.0% (2/41), ventricular fibrillation was 2.4 %(1/41), hypotentionwas 14.6 % (6/41).Conclusions In patients with AMI, intracoronary infusion of PBSCs is feasible and safe.

  9. Ionic mechanisms underlying cardiac toxicity of the organochloride solvent trichloromethane. (United States)

    Zhou, Yuan; Wu, Hui-Jun; Zhang, Yan-Hui; Sun, Hai-Ying; Wong, Tak-Ming; Li, Gui-Rong


    Trichloromethane (chloroform) is widely used for industrial chemical synthesis and also as an organic solvent in laboratories or ingredient of pesticides. Sudden death resulted from cardiac arrhythmias has been reported in clinic with acute trichloromethane intoxication. The present study was designed to investigate ionic mechanisms underlying arrhythmogenic effect (cardiac toxicity) of trichloromethane in isolated rat hearts and ventricular myocytes and HEK 293 cells stably expressing human Nav1.5, HCN2, or hERG channel using conventional electrophysiological approaches. It was found that trichloromethane (5mM) induced bradycardia and atrial-ventricular conduction blockade or ventricular fibrillation, and inhibited cardiac contractile function in isolated rat hearts. It shortened action potential duration (APD) in isolated rat ventricular myocytes, and increased the threshold current for triggering action potential, but had no effect on the inward rectifier K(+) current I(K1). However, trichloromethane significantly inhibited the L-type calcium current I(Ca.L) and the transient outward potassium current I(to) in a concentration-dependent manner (IC(50)s: 1.01 and 2.4mM, respectively). In HEK 293 cells stably expressing cardiac ion channel genes, trichloromethane reduced hNav1.5, HCN2, and hERG currents with IC(50)s of 8.2, 3.3, and 4.0mM, respectively. These results demonstrate for the first time that trichloromethane can induce bradycardia or ventricular fibrillation, and the arrhythmogenic effect of trichloromethane is related to the inhibition of multiple ionic currents including I(Ca.L), I(to), I(Na), HCN2, and hERG channels.


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    Full Text Available : BACKGROUND: The prolongation of spinal anaesthesia by using clonidine through the oral, intravenous and spinal route has been known. The new alpha-2 agonist, dexmedetomidine has been proved to prolong the spinal anaesthesia through the intrathecal route. We hypothesized that dexmedetomidine when administered intravenously following spinal block also prolongs spinal analgesia. A placebo controlled randomized controlled trial study was done. METHODOLOGY: 50 Patients were randomly allocated into two equal groups group D and group C. Both group received spinal hyperbaric bupivacaine 15mg intrathecally. Patients in group D received intravenously a loading dose of 1mcg/kg dexmedetomidine over 10 min followed by C maintenance dose of 0.5mcg/kg/hr till the end of surgery. Patients in group C (The control group received normal saline. The regression times to reach S1 sensory level and bromage 0 motor scale, hemodynamic changes and the level of sedation were recorded. RESULTS: The duration of sensory block was longer in intravenous dexmedetomidine group compared with control group (264.32+15.3 min vs 164.2+13.12 min, p 0.001. The duration of motor block was longer in dexmedetomidine group than control group (198.8+16.9 min vs 135.8+12.38 min, p 0.001 CONCLUSION: Intravenous dexmedetomidine administration prolonged the sensory and motor blocks of bupivacaine spinal analgesia with good sedation effect and hemodynamic stability. The incidence of bradycardia is significantly high when intravenous dexmedetomidine is used as an adjuvant to bupivacaine spinal anaesthesia. Dexmedetomidine induced bradycardia and hypotension can be easily managed with atropine and mephentermine respectively. Dexmedetomidine provides excellent sedation and postoperative analgesia.

  11. ECG changes in factory workers exposed to 27.2  MHz radiofrequency radiation. (United States)

    Chen, Qingsong; Xu, Guoyong; Lang, Li; Yang, Aichu; Li, Shilin; Yang, Liwen; Li, Chaolin; Huang, Hanlin; Li, Tao


    To research the effect of 27.2 MHz radiofrequency radiation on electrocardiograms (ECG), 225 female workers operating radiofrequency machines at a shoe factory were chosen as the exposure group and 100 female workers without exposure from the same factory were selected as the control group. The 6 min electric field strength that the female workers were exposed to was 64.0 ± 25.2 V/m (mean ± SD), which exceeded 61 V/m, the International Commission on Non-Ionizing Radiation Protection reference root mean square levels for occupational exposure. A statistical difference was observed between the exposed group and the control group in terms of the rate of sinus bradycardia (χ(2)  = 11.48, P = 0.003). When several known risk factors for cardiovascular disease were considered, including smoking, age, alcohol ingestion habit, and so on, the exposure duration was not an effective factor for ECG changes, sinus arrhythmia, or sinus bradycardia according to α = 0.05, while P = 0.052 for sinus arrhythmia was very close to 0.05. We did not find any statistical difference in heart rate, duration of the QRS wave (ventricular depolarization), or corrected QT intervals (between the start of the Q wave and end of the T wave) between the exposed and control groups. Occupational exposure to radiofrequency radiation was not found to be a cause of ECG changes after consideration of the confounding factors.

  12. Pharmacological Evidence that Histamine H3 Receptors Mediate Histamine-Induced Inhibition of the Vagal Bradycardic Out-flow in Pithed Rats. (United States)

    García, Mónica; García-Pedraza, José Ángel; Villalón, Carlos M; Morán, Asunción


    In vivo stimulation of cardiac vagal neurons induces bradycardia by acetylcholine (ACh) release. As vagal release of ACh may be modulated by autoreceptors (muscarinic M2 ) and heteroreceptors (including serotonin 5-HT1 ), this study has analysed the pharmacological profile of the receptors involved in histamine-induced inhibition of the vagal bradycardic out-flow in pithed rats. For this purpose, 180 male Wistar rats were pithed, artificially ventilated and pre-treated (i.v.) with 1 mg/kg atenolol, followed by i.v. administration of physiological saline (1 ml/kg), histamine (10, 50, 100 and 200 μg/kg) or the selective histamine H1 (2-pyridylethylamine), H2 (dimaprit), H3 (methimepip) and H4 (VUF 8430) receptor agonists (1, 10, 50 and 100 μg/kg each). Under these conditions, electrical stimulation (3, 6 and 9 Hz; 15 ± 3 V and 1 ms) of the vagus nerve resulted in frequency-dependent bradycardic responses, which were (i) unchanged during the infusions of saline, 2-pyridylethylamine, dimaprit or VUF 8430; and (ii) dose-dependently inhibited by histamine or methimepip. Moreover, the inhibition of the bradycardia caused by 50 μg/kg of either histamine or methimepip (which failed to inhibit the bradycardic responses to i.v. bolus injections of acetylcholine; 1-10 μg/kg) was abolished by the H3 receptor antagonist JNJ 10181457 (1 mg/kg, i.v.). In conclusion, our results suggest that histamine-induced inhibition of the vagal bradycardic out-flow in pithed rats is mainly mediated by pre-junctional activation of histamine H3 receptors, as previously demonstrated for the vasopressor sympathetic out-flow and the vasodepressor sensory CGRPergic (calcitonin gene-related peptide) out-flow.

  13. Acquired hemophilia as the cause of life-threatening hemorrhage in a 94-year-old man: a case report

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    Blanchard Elizabeth


    Full Text Available Abstract Introduction Acquired factor VIII deficiency is a rare entity that can lead to severe and life-threatening bleeding. We describe a case of severe bleeding from the tongue secondary to acquired hemophilia and discuss treatment options, including aminocaproic acid and recombinant factor VIII, which have not been widely reported in the literature for the management of such patients. Case presentation A 94-year-old Caucasian man presented to our institution with diffuse bruising and extensive bleeding from the tongue secondary to mechanical trauma. He had no prior history of bleeding and his medical history was unremarkable except for dementia and hypertension. Coagulation studies revealed a prolonged activated partial thromboplastin time and a mixing study was consistent with the presence of an inhibitor. Quantitative assays revealed a reduced level of factor VIII activity (1% and the presence of a factor VIII inhibitor, measured at seven Bethesda units, in the serum. Oral prednisone therapy (60mg/day was given. He also received intravenous aminocaproic acid and human concentrate of factor VIII (Humate-P and topical anti-thrombolytic agents (100 units of topical thrombin cream. His hospital course was prolonged because of persistent bleeding and the development of profuse melena. He required eight units of packed red blood cells for transfusion. Hospitalization was also complicated by bradycardia of unclear etiology, which started after infusion of aminocaproic acid. His activated partial thromboplastin time gradually normalized. He was discharged to a rehabilitation facility three weeks later with improving symptoms, stable hematocrit and resolving bruises. Conclusions Clinicians should suspect a diagnosis of acquired hemophilia in older patients with unexplained persistent and profound bleeding from uncommon soft tissues, including the tongue. Use of factor VIII (Humate-P and aminocaproic acid can be useful in this coagulopathy but


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    Laishram Chandralekha Singha


    Full Text Available BACKGROUND Dexmedetomidine, an α2 agonist is an approved drug for sedation and co-analgesia, but may cause hypotension and bradycardia. Ketamine, which provides profound analgesia and dissociative anaesthesia when used with dexmedetomidine may counteract the adverse haemodynamic effects as both have opposing actions on the cardiovascular system apart from providing satisfactory sedation and analgesia during minor surgical procedures. OBJECTIVE To study the sedoanalgesic efficacy and haemodynamic changes of dexmedetomidine infusion along with subanaesthetic dose of ketamine for minor surgical procedures. MATERIALS AND METHODS After Institutional Ethical Committee approval and informed patient consent, 30 ASA physical status I and II patients of age between 20-50 years planned for split skin grafting were selected and included in the study, which was done over a period of four months. The patients were given continuous infusion of loading dose of dexmedetomidine of 1 µg/kg over 10 minutes. Ketamine 0.8 mg/kg IV was given one minute before the start of the procedure and subsequently maintained with dexmedetomidine infusion @ 0.5 µg/kg/hr. Pain and sedation score, haemodynamic changes, requirement of additional dose of ketamine, and occurrence of emergence delirium were observed. RESULTS The sedation level during the procedure and the pain score in the immediate postoperative period were satisfactory. 28 patients did not have any discomfort whereas 2 patients required additional 0.8 mg/kg of IV ketamine. Hypotension occurred in 3 patients and bradycardia in 2 patients. There was nausea in 2 patients whereas emergence delirium or respiratory depression was not seen in any of the patients. CONCLUSION Dexmedetomidine infusion with subanaesthetic dose of ketamine can be used satisfactorily for minor surgical procedures.

  15. Cardiovascular effects of the essential oil of Croton zehntneri leaves in DOCA-salt hypertensive, conscious rats. (United States)

    de Siqueira, Rodrigo José Bezerra; Duarte, Gloria Pinto; Magalhães, Pedro Jorge Caldas; Lahlou, Saad


    This study investigated the cardiovascular effects of the essential oil of Croton zehntneri (EOCZ) in deoxycorticosterone-acetate (DOCA)-salt hypertensive rats. Furthermore, in vitro experiments using isolated thoracic aortic rings were performed to assess the vascular effects of the EOCZ. In conscious hypertensive rats, intravenous (i.v.) injections of EOCZ (1-20 mg/kg) induced rapid (2-4 s) and dose-dependent hypotension and bradycardia (phase 1). The hypotension was followed by a significant pressor effect that was more evident at the higher doses (10 and 20 mg/kg) of EOCZ. Hypotension and bradycardia of EOCZ (phase 1) were abolished and respectively reversed into pressor and tachycardiac effects by methylatropine (1 mg/kg, i.v.) pretreatment. In isolated endothelium-intact aortic preparations, increasing concentrations (1-1000 microg/mL) of EOCZ relaxed the potassium-induced contraction in a concentration-dependent manner with an IC50 (geometric mean [95% confidence interval]) value of 202.0 [92.0-443.7] microg/mL. This vasorelaxant effect remained unaffected by either mechanical removal of functional vascular endothelium (IC50 = 189.0 [159.4-224.7] microg/mL) or the addition of atropine (1 microM) (IC50 = 158.6 [79.8-316.2] microg/mL) in the perfusion medium. These data show that i.v. administration of EOCZ in DOCA-salt hypertensive rats induces a vago-vagal reflex decreases in heart rate and blood pressure (phase 1). EOCZ may induce a second and delayed hypotension due to its direct endothelium-independent vasorelaxant effects, but it seems to be buffered by the pressor component (subsequent to phase 1) of EOCZ. This pattern of blood pressure and heart rate responses to EOCZ seems unaltered by DOCA-salt hypertension, as was similar to that previously reported in conscious normotensive rats.

  16. New evidence for coupled clock regulation of the normal automaticity of sinoatrial nodal pacemaker cells: bradycardic effects of ivabradine are linked to suppression of intracellular Ca2+ cycling (United States)

    Yaniv, Yael; Sirenko, Syevda; Ziman, Bruce D.; Spurgeon, Harold A.; Maltsev, Victor A.; Lakatta, Edward G.


    Beneficial clinical bradycardic effects of ivabradine (IVA) have been interpreted solely on the basis of If inhibition, because IVA specifically inhibits If in sinoatrial nodal pacemaker cells (SANC). However, it has been recently hypothesized that SANC normal automaticity is regulated by crosstalk between an “M clock,” the ensemble of surface membrane ion channels, and a “Ca2+ clock,” the sarcoplasmic reticulum (SR). We tested the hypothesis that crosstalk between the two clocks regulates SANC automaticity, and that indirect suppression of the Ca2+ clock further contributes to IVA-induced bradycardia. IVA (3μM) not only reduced If amplitude by 45±6% in isolated rabbit SANC, but the IVA-induced slowing of the action potential (AP) firing rate was accompanied by reduced SR Ca2+ load, slowed intracellular Ca2+ cycling kinetics, and prolonged the period of spontaneous local Ca2+ releases (LCRs) occurring during diastolic depolarization. Direct and specific inhibition of SERCA2 by cyclopiazonic acid (CPA) had effects similar to IVA on LCR period and AP cycle length. Specifically, the LCR period and AP cycle length shift toward longer times almost equally by either direct perturbations of the M clock (IVA) or the Ca2+ clock (CPA), indicating that the LCR period reports the crosstalk between the clocks. Our numerical model simulations predict that entrainment between the two clocks that involves a reduction in INCX during diastolic depolarization is required to explain the experimentally AP firing rate reduction by IVA. In summary, our study provides new evidence that a coupled-clock system regulates normal cardiac pacemaker cell automaticity. Thus, IVA-induced bradycardia includes a suppression of both clocks within this system. PMID:23651631


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    Nayyar Iqbal


    Full Text Available Background: Enteric fever, a common infection in the tropics and endemic to India, often manifests as an acute febrile illness. However, presentation as fever of unknown origin (FUO is not uncommon in tropical countries. Methods: We aim to describe the clinical, laboratory and pathological features of cases hospitalized with fever of unknown origin and diagnosed as enteric fever. All culture proven cases of enteric fever were analyzed retrospectively over a period of three years from January 2011 to December 2013. Results: Seven of 88(8% cases with enteric fever presented as FUO. Abdominal pain was the most common symptom besides fever. Relative bradycardia and splenomegaly were uncommon. Thrombocytopenia was the most common haematological abnormality, while leucopenia was rare. Transaminase elevation was almost universal. S.Typhi and S.Paratyphi were isolated from six cases and one case respectively.  Yield of organisms from blood culture was superior to that of bone marrow aspirate. Multiple granulomas were identified in 4 out of 6 (67% of the bone marrows studied, including that due to S. Paratyphi and histiocytic hemophagocytosis was noted in two cases. Conclusion: FUO is a relatively common manifestation of enteric fever in the tropics. Clinical and laboratory features may be atypical in such cases, including absence of relative bradycardia, leucopenia and presence of thrombocytopenia, bicytopenia or pancytopenia.  Moreover, in endemic countries, enteric fever should be considered as a differential diagnosis, next to tuberculosis, in the evaluation of bone marrow granulomas in cases with FUO and culture correlation should be mandatory.

  18. Simultaneous parasympathetic and sympathetic activation reveals altered autonomic control of heart rate, vascular tension and epinephrine release in anaesthetized hypertensive rats

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    Torill eBerg


    Full Text Available Sympathetic hyperactivity and parasympathetic insufficiency characterize blood pressure control in genetic hypertension, but is difficult to demonstrate experimentally in anesthetized rats. Here we present a pharmacological approach to activate sympathetic and parasympathetic nerves simultaneously, and identify their contribution. Anaesthetized normotensive (WKY and spontaneously hypertensive rats (SHR were injected i.v. with 4-aminopyridine (4-AP, a voltage-sensitive K+ channel inhibitor. Blood pressure was recorded through a femoral artery catheter, cardiac output and heart rate (HR through an ascending aorta flow probe. Total peripheral vascular resistance (TPVR was calculated. 4-AP induced an immediate, atropine- and hexamethonium-sensitive bradycardia in WKY, and in strains, a subsequent, sustained tachycardia, and norepinephrine but not epinephrine release. The tachycardia was eliminated by reserpine, nadolol or right vagal nerve stimulation, but not adrenalectomy, scopolamine or hexamethonium. 4-AP-induced, atropine-sensitive bradycardia was observed in reserpinized or nadolol-treated SHR, where atropine also increased the late HR-response. 4-AP increased TPVR, transiently in WKY but sustained in SHR. Yohimbine but not phentolamine prevented TPVR down-regulation in WKY. Reserpine, phentolamine and prazosin eliminated the late vasoconstriction in SHR. Plasma epinephrine overflow increased in nadolol-treated SHR. Conclusions: 4-AP activated parasympathetic ganglion transmission and peripheral, sympathetic nerve norepinephrine release. The sympathetic component dominated the HR-response to 4-AP in SHR. α2-adrenceptor-dependent vasodilatation opposed norepinephrine-induced α1-adrenergic vasoconstriction in WKY, but not in SHR. A βAR-activated, probably vagal afferent mechanism, hampered adrenal epinephrine secretion in SHR. Thus, 4-AP exposed mechanisms, which contribute to hypertension, and may allow identification of the factors

  19. Influence of renal denervation on blood pressure, sodium and water excretion in acute total obstructive apnea in rats

    Directory of Open Access Journals (Sweden)

    J.V.M. Franquini


    Full Text Available Obstructive apnea (OA can exert significant effects on renal sympathetic nerve activity (RSNA and hemodynamic parameters. The present study focuses on the modulatory actions of RSNA on OA-induced sodium and water retention. The experiments were performed in renal-denervated rats (D; N = 9, which were compared to sham (S; N = 9 rats. Mean arterial pressure (MAP and heart rate (HR were assessed via an intrafemoral catheter. A catheter was inserted into the bladder for urinary measurements. OA episodes were induced via occlusion of the catheter inserted into the trachea. After an equilibration period, OA was induced for 20 s every 2 min and the changes in urine, MAP, HR and RSNA were recorded. Renal denervation did not alter resting MAP (S: 113 ± 4 vs D: 115 ± 4 mmHg or HR (S: 340 ± 12 vs D: 368 ± 11 bpm. An OA episode resulted in decreased HR and MAP in both groups, but D rats showed exacerbated hypotension and attenuated bradycardia (S: -12 ± 1 mmHg and -16 ± 2 bpm vs D: -16 ± 1 mmHg and 9 ± 2 bpm; P < 0.01. The basal urinary parameters did not change during or after OA in S rats. However, D rats showed significant increases both during and after OA. Renal sympathetic nerve activity in S rats increased (34 ± 9% during apnea episodes. These results indicate that renal denervation induces elevations of sodium content and urine volume and alters bradycardia and hypotension patterns during total OA in unconscious rats.

  20. Use of antiarrhythmic drugs in elderly patients

    Institute of Scientific and Technical Information of China (English)

    Hon-Chi Lee; Kristin TL Huang; Win-Kuang Shen


    Human aging is a global issue with important implications for current and future incidence and prevalence of health conditions and disability.Cardiac arrhythmias,including atrial fibrillation,sudden cardiac death,and bradycardia requiring pacemaker placement,all increase exponentially after the age of 60.It is important to distinguish between the normal,physiological consequences of aging on cardiacelectrophysiology and the abnormal,pathological alterations.The age-related cardiac changes include ventricular hypertrophy,senileamyloidosis,cardiac valvular degenerative changes and annular calcification,fibrous infiltration of the conduction system,and loss of naturalpacemaker cells and these changes could have a profound effect on the development of arrhythmias.The age-related cardiac electrophysiological changes include up- and down-regulation of specific ion channel expression and intracellular Ca2+ overload which promote the development of cardiac an-hythmias.As ion channels are the substrates of antiarrhythmic drugs,it follows that the pharmacoldnetics and pharmacodynamics of these drugs will also change with age.Aging alters the absorption,distribution,metabolism,and elimination of antiarrhythmic drugs,so liver and kidney function must be monitored to avoid potential adverse drug effects,and antiarrhythmic dosing may need to be adjusted for age.Elderly patients are also more susceptible to the side effects of many antiarrhythmics,including bradycardia,orthostatic hypotension,urinary retention,and falls.Moreover,the choice of antiarrhythmic drugs in the elderly patient is frequently complicated by the presence of co-morbid conditions and by polyphanmacy,and the astute physician must pay careful attention to potential drug-drug interactions.Finally,it is important to remember that the use of antiarrhythmic drugs in elderly patients must be individualized and tailored to each patient's physiology,disease processes,and medication regimen.

  1. Chemoreceptors and cardiovascular control in acute and chronic systemic hypoxia

    Directory of Open Access Journals (Sweden)

    J.M. Marshall


    Full Text Available This review describes the ways in which the primary bradycardia and peripheral vasoconstriction evoked by selective stimulation of peripheral chemoreceptors can be modified by the secondary effects of a chemoreceptor-induced increase in ventilation. The evidence that strong stimulation of peripheral chemoreceptors can evoke the behavioural and cardiovascular components of the alerting or defence response which is characteristically evoked by novel or noxious stimuli is considered. The functional significance of all these influences in systemic hypoxia is then discussed with emphasis on the fact that these reflex changes can be overcome by the local effects of hypoxia: central neural hypoxia depresses ventilation, hypoxia acting on the heart causes bradycardia and local hypoxia of skeletal muscle and brain induces vasodilatation. Further, it is proposed that these local influences can become interdependent, so generating a positive feedback loop that may explain sudden infant death syndrome (SIDS. It is also argued that a major contributor to these local influences is adenosine. The role of adenosine in determining the distribution of O2 in skeletal muscle microcirculation in hypoxia is discussed, together with its possible cellular mechanisms of action. Finally, evidence is presented that in chronic systemic hypoxia, the reflex vasoconstrictor influences of the sympathetic nervous system are reduced and/or the local dilator influences of hypoxia are enhanced. In vitro and in vivo findings suggest this is partly explained by upregulation of nitric oxide (NO synthesis by the vascular endothelium which facilitates vasodilatation induced by adenosine and other NO-dependent dilators and attenuates noradrenaline-evoked vasoconstriction.

  2. Effect of Microinfusion of Angiotensin Ⅱ into the RVLM in Rats on the Baroreceptor Reflex Sensitivity

    Institute of Scientific and Technical Information of China (English)

    ZHANGFeng; GAOXing-ya; ZHUGuo-qing; ZHONGWan-hua


    The present study was designed to investigate the effect of microinfusion anglotensin Ⅱ (Ang Ⅱ ),Ang Ⅱ type l(AT1)receptor antagonist lesartan into the rostral ventrolateral medulla(RVLM)on the baroreceptor reflex sensitivity(BRS)in urethane-anesthetized rats. Methods: Reflex changes in heart rate(HR)were elicited by bolus intravenous injection of phenylephrine before and during RVLM microinfusion of saline(0.5μl/h), Ang Ⅱ(1.Snmol/h), losartan (250 nmol/h), and Ang Ⅱ (1.5 nmol/h) pretreated with microinjection of losartan (50 nmol/0.51 μl)into the RVLM. The average ratio between changes in HR in beats per minute(beats, min-1 )and changes in mean arteriaI pressutre [ MAP,mmHg(1 mmHg = 0.133 kPa) ] was used as an index of BRS. Results : Ang Ⅱ resulted in a significant decrease in the BRS for reflex bradycardia compared with control( - 2.1 ~ 0.1 vs - 3.9 + 0.4 beats.min-1·mmHg-1 ).Microinfusion of losartan had no significant effect on BRS for reflex bradycardia.The effect of Ang ][ was almost completely abolished by pretreatment with microinjection of losartan. Conc/us/on: These results showed that the exogenous Ang II in the RVLM produces inhibitory modulation of BRS, which is mediated by AT2 receptor.However,AT1 receptor in the RVLM is not involved in the tonic control of BRS.

  3. Bitopic Sphingosine 1-Phosphate Receptor 3 (S1P3) Antagonist Rescue from Complete Heart Block: Pharmacological and Genetic Evidence for Direct S1P3 Regulation of Mouse Cardiac Conduction (United States)

    Sanna, M. Germana; Vincent, Kevin P.; Repetto, Emanuela; Nguyen, Nhan; Brown, Steven J.; Abgaryan, Lusine; Riley, Sean W.; Leaf, Nora B.; Cahalan, Stuart M.; Kiosses, William B.; Kohno, Yasushi; Brown, Joan Heller; McCulloch, Andrew D.


    The molecular pharmacology of the G protein–coupled receptors for sphingosine 1-phosphate (S1P) provides important insight into established and new therapeutic targets. A new, potent bitopic S1P3 antagonist, SPM-354, with in vivo activity, has been used, together with S1P3-knockin and S1P3-knockout mice to define the spatial and functional properties of S1P3 in regulating cardiac conduction. We show that S1P3 is a key direct regulator of cardiac rhythm both in vivo and in isolated perfused hearts. 2-Amino-2-[2-(4-octylphenyl)ethyl]propane-1,3-diol in vivo and S1P in isolated hearts induced a spectrum of cardiac effects, ranging from sinus bradycardia to complete heart block, as measured by a surface electrocardiogram in anesthetized mice and in volume-conducted Langendorff preparations. The agonist effects on complete heart block are absent in S1P3-knockout mice and are reversed in wild-type mice with SPM-354, as characterized and described here. Homologous knockin of S1P3-mCherry is fully functional pharmacologically and is strongly expressed by immunohistochemistry confocal microscopy in Hyperpolarization Activated Cyclic Nucleotide Gated Potassium Channel 4 (HCN4)-positive atrioventricular node and His-Purkinje fibers, with relative less expression in the HCN4-positive sinoatrial node. In Langendorff studies, at constant pressure, SPM-354 restored sinus rhythm in S1P-induced complete heart block and fully reversed S1P-mediated bradycardia. S1P3 distribution and function in the mouse ventricular cardiac conduction system suggest a direct mechanism for heart block risk that should be further studied in humans. A richer understanding of receptor and ligand usage in the pacemaker cells of the cardiac system is likely to be useful in understanding ventricular conduction in health, disease, and pharmacology. PMID:26494861

  4. Cardiac arrest upon induction of anesthesia in children with cardiomyopathy: an analysis of incidence and risk factors.

    LENUS (Irish Health Repository)

    Lynch, Johanne


    INTRODUCTION: It is thought that patients with cardiomyopathy have an increased risk of cardiac arrest on induction of anesthesia, but there is little available data. The purpose of this study was to identify the incidence and potential risk factors for cardiac arrest upon induction of anesthesia in children with cardiomyopathy in our institution. METHODS: A retrospective chart review was performed. Eligible patients included patients admitted between 1998 and 2008 with the International Statistical Classification of Disease code for cardiomyopathy (ICD-9 code 425) who underwent airway intervention for sedation or general anesthesia in the operating room, cardiac diagnostic and interventional unit (CDIU) or intensive care unit. Patients undergoing emergency airway intervention following cardiovascular collapse were excluded. For each patient, we recorded patient demographics, disease severity, anesthesia location, and anesthetic technique. RESULTS: One hundred and twenty-nine patients with cardiomyopathy underwent a total of 236 anesthetic events, and four cardiac arrests were identified. One was related to bradycardia (HR<60), two were attributed to bradycardia in association with severe hypotension (systolic blood pressure<45), and the fourth arrest was related to isolated severe hypotension. Two occurred in the operating suite and two in the CDIU. There was no resulting mortality. One patient progressed to heart transplantation. Multiple combinations of anesthetic drugs were used for induction of anesthesia. CONCLUSION: We performed a review of the last 10 years of anesthesia events in children with cardiomyopathy. We report four cardiac arrests in two patients and 236 anesthetic events (1.7%). To the best of our knowledge, this is the largest review of these patients to date but is limited by its retrospective nature. The low cardiac arrest incidence prevents the identification of risk factors and the development of a cardiac arrest risk predictive clinical

  5. Parasympathetic preganglionic cardiac motoneurons labeled after voluntary diving

    Directory of Open Access Journals (Sweden)

    W Michael ePanneton


    Full Text Available A dramatic bradycardia is induced by underwater submersion in vertebrates. The location of parasympathetic preganglionic cardiac motor neurons driving this aspect of the diving response was investigated using cFos immunohistochemistry combined with retrograde transport of cholera toxin subunit B (CTB to double-label neurons. After pericardial injections of CTB, trained rats voluntarily dove underwater, and their heart rates dropped immediately to 95±2bpm, an 80% reduction. After immunohistochemical processing, the vast majority of CTB labeled neurons were located in the reticular formation from the rostral cervical spinal cord to the facial motor nucleus, confirming previous studies. Labeled neurons caudal to the rostral ventrolateral medulla were usually spindle-shaped aligned along an oblique line running from the dorsal vagal nucleus to the ventrolateral reticular formation, while those more rostrally were multipolar with extended dendrites. Nine percent of retrogradely-labeled neurons were positive for both cFos and CTB after diving and 74% of these were found rostral to the obex. CTB also was transported transganglionically in primary afferent fibers, resulting in large granular deposits in dorsolateral, ventrolateral, and commissural subnuclei of the nucleus tractus solitarii and finer deposits in lamina I and IV-V of the trigeminocervical complex. The overlap of parasympathetic preganglionic cardiac motor neurons activated by diving with those activated by baro- and chemoreceptors in the rostral ventrolateral medulla is discussed. Thus the profound bradycardia seen with underwater submersion reinforces the notion that the mammalian diving response is the most powerful autonomic reflex known.

  6. Effect of selective vagal nerve stimulation on blood pressure, heart rate and respiratory rate in rats under metoprolol medication. (United States)

    Gierthmuehlen, Mortimer; Plachta, Dennis T T


    Selective vagal nerve stimulation (sVNS) has been shown to reduce blood pressure without major side effects in rats. This technology might be the key to non-medical antihypertensive treatment in patients with therapy-resistant hypertension. β-blockers are the first-line therapy of hypertension and have in general a bradycardic effect. As VNS itself can also promote bradycardia, it was the aim of this study to investigate the influence of the β1-selective blocker Metoprolol on the effect of sVNS especially with respect to the heart rate. In 10 male Wistar rats, a polyimide multichannel-cuff electrode was placed around the vagal nerve bundle to selectively stimulate the aortic depressor nerve fibers. The stimulation parameters were adapted to the thresholds of individual animals and were in the following ranges: frequency 30-50 Hz, amplitude 0.3-1.8 mA and pulse width 0.3-1.3 ms. Blood pressure responses were detected with a microtip transducer in the carotid artery, and electrocardiography was recorded with s.c. chest electrodes. After IV administration of Metoprolol (2 mg kg(-1) body weight), the animals' mean arterial blood pressure (MAP) and heart rate (HR) decreased significantly. Although the selective electrical stimulation of the baroreceptive fibers reduced MAP and HR, both effects were significantly alleviated by Metoprolol. As a side effect, the rate of stimulation-induced apnea significantly increased after Metoprolol administration. sVNS can lower the MAP under Metoprolol without causing severe bradycardia.

  7. Metoclopramide-induced cardiac arrest

    Directory of Open Access Journals (Sweden)

    Martha M. Rumore


    Full Text Available The authors report a case of cardiac arrest in a patient receiving intravenous (IV metoclopramide and review the pertinent literature. A 62-year-old morbidly obese female admitted for a gastric sleeve procedure, developed cardiac arrest within one minute of receiving metoclopramide 10 mg via slow intravenous (IV injection. Bradycardia at 4 beats/min immediately appeared, progressing rapidly to asystole. Chest compressions restored vital function. Electrocardiogram (ECG revealed ST depression indicative of myocardial injury. Following intubation, the patient was transferred to the intensive care unit. Various cardiac dysrrhythmias including supraventricular tachycardia (SVT associated with hypertension and atrial fibrillation occurred. Following IV esmolol and metoprolol, the patient reverted to normal sinus rhythm. Repeat ECGs revealed ST depression resolution without pre-admission changes. Metoclopramide is a non-specific dopamine receptor antagonist. Seven cases of cardiac arrest and one of sinus arrest with metoclopramide were found in the literature. The metoclopramide prescribing information does not list precautions or adverse drug reactions (ADRs related to cardiac arrest. The reaction is not dose related but may relate to the IV administration route. Coronary artery disease was the sole risk factor identified. According to Naranjo, the association was possible. Other reports of cardiac arrest, severe bradycardia, and SVT were reviewed. In one case, five separate IV doses of 10 mg metoclopramide were immediately followed by asystole repeatedly. The mechanism(s underlying metoclopramide’s cardiac arrest-inducing effects is unknown. Structural similarities to procainamide may play a role. In view of eight previous cases of cardiac arrest from metoclopramide having been reported, further elucidation of this ADR and patient monitoring is needed. Our report should alert clinicians to monitor patients and remain diligent in surveillance and

  8. Successful treatment of a massive metoprolol overdose using intravenous lipid emulsion and hyperinsulinemia/euglycemia therapy. (United States)

    Barton, Cassie A; Johnson, Nathan B; Mah, Nathan D; Beauchamp, Gillian; Hendrickson, Robert


    Adrenergic β-antagonists, commonly known as β-blockers, are prescribed for many indications including hypertension, heart failure, arrhythmias, and migraines. Metoprolol is a moderately lipophilic β-blocker that in overdose causes direct myocardial depression leading to bradycardia, hypotension, and the potential for cardiovascular collapse. We describe the case of a 59-year-old man who intentionally ingested ~7.5 g of metoprolol tartrate. Initial treatment of bradycardia and hypotension included glucagon, atropine, dopamine, and norepinephrine. Despite these treatment modalities, the patient developed cardiac arrest. Intravenous lipid emulsion (ILE) and hyperinsulinemia/euglycemia (HIE) therapies were initiated during advanced cardiac life support and were immediately followed by return of spontaneous circulation. Further treatment included gastric lavage, activated charcoal, continued vasopressor therapy, and a repeat bolus of ILE. The patient was weaned off vasoactive infusions and was extubated within 24 hours. HIE therapy was continued for 36 hours after metoprolol ingestion. A urine β-blocker panel using mass spectrometry revealed a metoprolol concentration of 120 ng/ml and the absence of other β-blocking agents. To date, no clear treatment guidelines are available for β-blocker overdose, and the response to toxic concentrations is highly variable. In this case of a life-threatening single-agent metoprolol overdose, the patient was successfully treated with HIE and ILE therapy. Due to the increasing frequency with which ILE and HIE are being used for the treatment of β-blocker overdose, clinicians should be aware of their dosing strategies and indications.

  9. Leptin impairs cardiovagal baroreflex function at the level of the solitary tract nucleus. (United States)

    Arnold, Amy C; Shaltout, Hossam A; Gallagher, Patricia E; Diz, Debra I


    Circulating leptin is elevated in some forms of obesity-related hypertension, associated with impaired baroreflex function. Leptin receptors are present on vagal afferent fibers and neurons within the solitary tract nucleus, providing an anatomic distribution consistent with baroreflex modulation. Although solitary tract nucleus microinjection of 144 fmol/60 nL of leptin had no significant effect on baroreflex sensitivity for control of the heart rate in urethane/chloralose-anesthetized Sprague-Dawley rats, 500 fmol of leptin impaired baroreflex sensitivity for bradycardia in response to increases in pressure (1.15+/-0.04 versus 0.52+/-0.12 ms/mm Hg; P<0.01). Transgenic ASrAOGEN rats with low brain angiotensinogen have an upregulation of the leptin receptor and p85 alpha mRNA in the dorsal medulla relative to Sprague-Dawley rats. Consistent with these observations, the response to leptin was enhanced in ASrAOGEN rats, because both the 144-fmol (1.46+/-0.08 versus 0.75+/-0.10 ms/mm Hg; P<0.001) and 500-fmol (1.36+/-0.32 versus 0.44+/-0.06 ms/mm Hg; P<0.05) leptin microinjections impaired baroreflex sensitivity. At these doses, leptin microinjection had no effect on resting pressure, heart rate, or the tachycardic response to decreases in pressure in Sprague-Dawley or ASrAOGEN rats. Thus, exogenous leptin at sites within the solitary tract nucleus impairs the baroreflex sensitivity for bradycardia induced by increases in arterial pressure, consistent with a permissive role in mediating increases in arterial pressure. Baroreflex inhibition was enhanced in animals with evidence of increased leptin receptor and relevant signaling pathway mRNA.

  10. Can we measure the spiral and uterine artery blood flow by real-time sonography and Doppler indices to predict spontaneous miscarriage in a normal-risk population? (United States)

    Özkan, Mehmet Burak; Ozyazici, Elif; Emiroglu, Baris; Özkara, Enis


    Introduction: The predictive value of spiral artery flow Doppler measurements of a subsequent early miscarriage in first trimester pregnancy is explored here. Objective: The aim of this study is to determine uterine and spiral artery blood flow changes in first trimester subsequent miscarriages and correlate within the mechanisms of the Doppler indicies. Study design: The uterine artery and spiral artery pulsatility and resistance indexes, systolic and diastolic ratios, acceleration times, and blood flow of both the right and left uterine arteries were obtained by trans vaginal color Doppler ultrasonography in consecutive viable pregnancies between 5 and 12 gestational week. Women were subsequently classified as having continuing pregnancies or pregnancy loss before 20 weeks gestation. To predict subsequent pregnancy loss, Doppler findings were adjusted for maternal age, history of previous abortion, presence of subchorionic hematoma, embryonic bradycardia, and gestational age by means of multivariate logistic regression analysis. The cut-off values are used for the ROC curve. Results: Twenty-five pregnancies (11.7%) were spontaneously aborted before 20 weeks of gestational age. In 29 (13.6%) cases there were previously abortion history, 30 (14%) had bradycardia, and 37 (17.3%) had subchoronic hematoma. Regarding the parameters of uterine and spiral artery pulsatility and resistive index, acceleration time, systolic/diastolic ratios and blood flows, only uterine artery S/D low values were significantly associated with pregnancy loss in the multivariate logistic regression analysis (P = 0.0001,95% CI: 4.968-55.675). Conclusion: The uterine artery systolic/diastolic ratios have a predictive value for early pregnancy loss and seem to be useful as a marker. On the other hand, spiral artery changes could be so local that they cannot be determined by the parameters of spectral Doppler techniques. This suggests that uterine vascular bed alterations should be measured to

  11. Effects of aerobic exercise training on heart rate variability during wakefulness and sleep and cardiorespiratory responses of young and middle-aged healthy men

    Directory of Open Access Journals (Sweden)

    A.M. Catai


    Full Text Available The purpose of the present study was to evaluate the effects of aerobic physical training (APT on heart rate variability (HRV and cardiorespiratory responses at peak condition and ventilatory anaerobic threshold. Ten young (Y: median = 21 years and seven middle-aged (MA = 53 years healthy sedentary men were studied. Dynamic exercise tests were performed on a cycloergometer using a continuous ramp protocol (12 to 20 W/min until exhaustion. A dynamic 24-h electrocardiogram was analyzed by time (TD (standard deviation of mean R-R intervals and frequency domain (FD methods. The power spectral components were expressed as absolute (a and normalized units (nu at low (LF and high (HF frequencies and as the LF/HF ratio. Control (C condition: HRV in TD (Y: 108, MA: 96 ms; P<0.05 and FD - LFa, HFa - was significantly higher in young (1030; 2589 ms²/Hz than in middle-aged men (357; 342 ms²/Hz only during sleep (P<0.05; post-training effects: resting bradycardia (P<0.05 in the awake condition in both groups; VO2 increased for both groups at anaerobic threshold (P<0.05, and at peak condition only in young men; HRV in TD and FD (a and nu was not significantly changed by training in either groups. The vagal predominance during sleep is reduced with aging. The resting bradycardia induced by short-term APT in both age groups suggests that this adaptation is much more related to intrinsic alterations in sinus node than in efferent vagal-sympathetic modulation. Furthermore, the greater alterations in VO2 than in HRV may be related to short-term APT.

  12. Excitatory amino acid receptor blockade within the caudal pressor area and rostral ventrolateral medulla alters cardiovascular responses to nucleus raphe obscurus stimulation in rats

    Directory of Open Access Journals (Sweden)

    Silva N.F.


    Full Text Available Pressor responses elicited by stimulation of the nucleus raphe obscurus (NRO depend on the integrity of the rostral ventrolateral medulla (RVLM. Therefore, to test the participation of excitatory amino acid (EAA receptors in the cardiovascular responses evoked by NRO stimulation (1 ms, 100 Hz, 40-70 µA, for 10 s, the EAA antagonist kynurenic acid (Kyn was microinjected at different sites in the ventrolateral medullar surface (2.7 nmol/200 nl of male Wistar rats (270-320 g, N = 39 and NRO stimulation was repeated. The effects of NRO stimulation were: hypertension (deltaMAP = +43 ± 1 mmHg, P<0.01, bradycardia (deltaHR = -30 ± 7 bpm, P<0.01 and apnea. Bilateral microinjection of Kyn into the RVLM, which did not change baseline parameters, almost abolished the bradycardia induced by NRO stimulation (deltaHR = -61 ± 3 before vs -2 ± 3 bpm after Kyn, P<0.01, N = 7. Unilateral microinjection of Kyn into the CVLM did not change baseline parameters or reduce the pressor response to NRO stimulation (deltaMAP = +46 ± 5 before vs +48 ± 5 mmHg after Kyn, N = 6. Kyn bilaterally microinjected into the caudal pressor area reduced blood pressure and heart rate and almost abolished the pressor response to NRO stimulation (deltaMAP = +46 ± 4 mmHg before vs +4 ± 2 mmHg after Kyn, P<0.01, N = 7. These results indicate that EAA receptors on the medullary ventrolateral surface play a role in the modulation of the cardiovascular responses induced by NRO stimulation, and also suggest that the RVLM participates in the modulation of heart rate responses and that the caudal pressor area modulates the pressor response following NRO stimulation.

  13. Parasympathetic neurons in the cranial medial ventricular fat pad on the dog heart selectively decrease ventricular contractility. (United States)

    Dickerson, L W; Rodak, D J; Fleming, T J; Gatti, P J; Massari, V J; McKenzie, J C; Gillis, R A


    We hypothesized that selective control of ventricular contractility might be mediated by postganglionic parasympathetic neurons in the cranial medial ventricular (CMV) ganglion plexus located in a fat pad at the base of the aorta. Sinus rate, atrioventricular (AV) conduction (ventricular rate during atrial pacing), and left ventricular contractile force (LV dP/dt during right ventricular pacing) were measured in eight chloralose-anesthetized dogs both before and during bilateral cervical vagus stimulation (20-30 V, 0.5 ms pulses, 15-20 Hz). Seven of these dogs were tested under beta-adrenergic blockade (propranolol, 0.8 mg kg(-1) i.v.). Control responses included sinus node bradycardia or arrest during spontaneous rhythm, high grade AV block or complete heart block, and a 30% decrease in contractility from 2118 +/- 186 to 1526 +/- 187 mm Hg s(-1) (P 0.05) decrease in contractility but still elicited the same degree of sinus bradycardia and AV block (N = 8, P < 0.05). Five dogs were re-tested 3 h after trimethaphan fat pad injection, at which time blockade of vagally-induced negative inotropy was partially reversed, as vagal stimulation decreased LV dP/dt by 19%. The same dose of trimethaphan given either locally into other fat pads (PVFP or IVC-ILA) or systemically (i.v.) had no effect on vagally-induced negative inotropy. Thus, parasympathetic ganglia located in the CMV fat pad mediated a decrease in ventricular contractility during vagal stimulation. Blockade of the CMV fat pad had no effect on vagally-mediated slowing of sinus rate or AV conduction.

  14. Electrical stimulation of the aortic depressor nerve in conscious rats overcomes the attenuation of the baroreflex in chronic heart failure. (United States)

    Pinto, Tomás O C Teixeira; Lataro, Renata M; Castania, Jaci A; Durand, Marina T; Silva, Carlos A A; Patel, Kaushik P; Fazan, Rubens; Salgado, Helio C


    Chronic heart failure (CHF) is characterized by autonomic dysfunction combined with baroreflex attenuation. The hypotensive and bradycardic responses produced by electrical stimulation of the aortic depressor nerve (ADN) were examined in conscious CHF and control male Wistar rats (12-13 wk old). Furthermore, the role of parasympathetic and sympathetic nervous system in mediating the cardiovascular responses to baroreflex activation was evaluated by selective β1-adrenergic and muscarinic receptor antagonists. CHF was induced by myocardial infarction. After 6 wk, the subjects were implanted with electrodes for ADN stimulation. Twenty-four hours later, electrical stimulation of the ADN was applied for 20 s using five different frequencies (5, 15, 30, 60, and 90 Hz), while the arterial pressure was recorded by a catheter implanted into the femoral artery. Electrical stimulation of the ADN elicited progressive and similar hypotensive and bradycardic responses in control (n = 12) and CHF (n = 11) rats, while the hypotensive response was not affected by methylatropine. Nevertheless, the reflex bradycardia was attenuated by methylatropine in control, but not in CHF rats. Atenolol did not affect the hypotensive or bradycardic response in either group. The ADN function was examined under anesthesia through electroneurographic recordings. The arterial pressure-ADN activity relationship was attenuated in CHF rats. In conclusion, despite the attenuation of baroreceptor function in CHF rats, the electrical stimulation of the ADN elicited a stimulus-dependent hypotension and bradycardia of similar magnitude as observed in control rats. Therefore, electrical activation of the aortic baroreflex overcomes both the attenuation of parasympathetic function and the sympathetic overdrive.

  15. Stop or move: Defensive strategies in humans. (United States)

    Bastos, Aline F; Vieira, Andre S; Oliveira, Jose M; Oliveira, Leticia; Pereira, Mirtes G; Figueira, Ivan; Erthal, Fatima S; Volchan, Eliane


    Threatening cues and surrounding contexts trigger specific defensive response patterns. Potential threat evokes attentive immobility; attack evokes flight when escape is available and immobility when escape is blocked. Tonic immobility installs when threat is overwhelming and life-risky. In humans, reduced body sway characterizes attentive and tonic immobility, the former with bradycardia, and the later with expressive tachycardia. Here, we investigate human defensive strategies in the presence or absence of an escape route. We employed pictures depicting a man carrying a gun and worked with participants exposed to urban violence. In pictures simulating more possibility of escape, the gun was directed away from the observer; in those simulating higher risk and less chance of escape, the gun was directed toward the observer. Matched control pictures depicted similar layouts, but a non-lethal object substituted the gun. Posturographic and electrocardiographic recordings were collected. Amplitude of sway and heart rate were higher for gun directed-away and lower for gun direct-toward. Compared to their respective matched controls, there was a general increase in the amplitude of sway for the gun directed-away pictures; and a reduction in back-and-forth sway and in heart rate for gun directed-toward pictures. Taken together, those measures suggest that, when exposed to threat invading their margin of safety in a context indicating possible escape route, humans, as non-human species, engage in active escape, resembling the flight stage of the defensive cascade. When facing threat indicating less possibility of escape, humans present an immobile response with bradycardia.

  16. Accuracy of physical examination in the diagnosis of hypothyroidism: a cross-sectional, double-blind study

    Directory of Open Access Journals (Sweden)

    Indra R


    Full Text Available Background: Hypothyroidism is a common, potentially treatable endocrine disorder. Since hypothyroidism is not always associated with the signs and symptoms typically attributed to it, the diagnosis is often missed. Conversely, patients with typical signs and symptoms may not have the disease when laboratory tests are performed. Aims: We aimed to determine the accuracy of physical examination in the diagnosis of hypothyroidism. Setting and design: Prospective, hospital-based, cross-sectional diagnostic study. Material and Methods: Consecutive outpatients from the medicine department were screened and an independent comparison of physical signs (coarse skin, puffy face, slow movements, bradycardia, pretibial oedema and ankle reflex against thyroid hormone assay (TSH and FT4 was performed. Statistical analysis: Diagnostic accuracy was measured as sensitivity, specificity, positive likelihood ratios, negative likelihood ratios and positive and negative predictive values. Results: Of the 1450 patients screened, 130 patients (102 women and 28 men underwent both clinical examination and thyroid function tests. Twenty-three patients (18% were diagnosed to have hypothyroidism by thyroid hormone assays. No single sign could easily discriminate a euthyroid from a hypothyroid patient (range of positive likelihood ratio (LR+ 1.0 to 3.88; range of negative likelihood ratio (LR-: 0.42 to 1.0. No physical sign generated a likelihood ratio large enough to increase the post-test probability significantly. The combination of signs that had the highest likelihood ratios (coarse skin, bradycardia and delayed ankle reflex was associated with modest accuracy (LR+ 3.75; LR- 0.48. Conclusion: Clinicians cannot rely exclusively on physical examination to confirm or rule out hypothyroidism. Patients with suspected hypothyroidism require a diagnostic workup that includes thyroid hormone assays.

  17. Analysis of Atropine test in 97 cases%阿托品试验97例分析

    Institute of Scientific and Technical Information of China (English)

    黄丽红; 曲鹏


    [ Objective ] To discuss the clinical value of atropine test on the suspected sick sinus syndrome (SSS) cases.[ Method] Atropine test was performed in 97 patients with suspected SSS who had sinus bradycardia. Transesophageal atrial pacing (TAP) in the positive ones was used to confirm the diagnosis of SSS. [ Results] Among the 97 cases,there were 78whose fastest heart rates were less than 90 beats per minute. Positive rate was 80.4%. And according to the TAP, it was indicated that there were totally 70 SSS sufferers in those 78 cases. The percentage of conformity was 89.7%. [ Conclusion]Atropine test is a simple method and it is better to choose the suspected SSS sufferers that have sinus bradycardia for atropine test so that to raise the percentage of diagnosis.%[目的]探讨对疑有病态窦房结综合征(sick sinus syndrome,SSS)患者行阿托品试验的临床价值.[方法]对97例疑有SSS的窦性心动过缓患者做阿托品试验,其中阳性者行食管心房调搏检查以进一步明确SSS之诊断.[结果]97例中78例最快心率<90次/min,阳性率80.4%;78例行食管心房调搏提示SSS 70例,符合率89.7%.[结论]阿托品试验方法简便,应用于疑有SSS的窦性心动过缓患者可提高对SSS的检出率.

  18. Antihypertensive responses elicited by central moxonidine in rats: possible role of nitric oxide. (United States)

    Moreira, Thiago Santos; Takakura, Ana Carolina Thomaz; Sato, Monica Akemi; Menani, José Vanderlei; Colombari, Eduardo


    In the present study, we investigated the effects of pretreatment with NG-nitro-L-arginine methyl ester (L-NAME) (nitric oxide synthase inhibitor) injected intravenously (IV) on the hypotension, bradycardia, and vasodilation produced by moxonidine (alpha2-adrenergic/imidazoline receptor agonist) injected into the fourth brain ventricle (4th V) in rats submitted to acute hypertension that results from baroreflex blockade by bilateral injections of kynurenic acid (kyn, glutamatergic receptor antagonist) into the nucleus of the solitary tract (NTS) or in normotensive rats. Male Wistar rats (n=5 to 7/group) anesthetized with IV urethane (1.0 g kg(-1) of body weight) and alpha-chloralose (60 mg kg(-1) of body weight) were used. Bilateral injections of kyn (2.7 nmol 100 nL(-1)) into the NTS increased baseline mean arterial pressure (148 +/- 11 mm Hg, vs. control: 102 +/- 4 mm Hg) and baseline heart rate (417 +/- 11 bpm, vs. control: 379 +/- 6 bpm). Moxonidine (20 nmol microL(-1)) into the 4th V reduced mean arterial pressure and heart rate to similar levels in rats treated with kyn into the NTS (68 +/- 9 mm Hg and 359 +/- 7 bpm) or in control normotensive rats (66 +/- 7 mm Hg and 362 +/- 8 bpm, respectively). The pretreatment with L-NAME (25 micromol kg, IV) attenuated the hypotension produced by moxonidine into the 4th V in rats treated with kyn (104 +/- 6 mm Hg) or in normotensive rats (95 +/- 8 mm Hg), without changing bradycardia. Moxonidine into the 4th V also reduced renal, mesenteric, and hindquarter vascular resistances in rats treated or not with kyn into the NTS and the pretreatment with L-NAME IV reduced these effects of moxonidine. Therefore, these data indicate that nitric oxide mechanisms are involved in hypotension and mesenteric, renal, and hindquarter vasodilation induced by central moxonidine in normotensive and in acute hypertensive rats.

  19. Comparing the preventive effect of 2 percent Topical Lidocaine and Intravenous Atropine on oculocardiac reflex in Ophthalmological Surgeries under General Anesthesia

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    Parvin Sajedi


    Full Text Available Background: The current study aimed to determine preventive effect of 2 percent topical xylocaine on oculocardiac reflex in ophthalmological surgeries except strabismus, including retinal detachment and vitrectomy with scleral buckling under general anesthesia. Methods: A randomized controlled clinical trial was carried out on 150 patients aged 18-90 years undergoing ophthalmological surgeries under general anesthesia. Samples randomly divided into the experimental group (received four drops of 2 percent topical xylocaine instilled in desired eye and control group (received 0.5 mg atropine sulfate injection. Systolic, diastolic and mean arterial blood pressure of patients and baseline heart rate were recorded. They were compared regarding the incidence of bradycardia, heart rate less than 60 beats/minute, hypotension and blood pressure less than 90 mm/Hg. Data were analyzed by Statistical Package for the Social Sciences software version 20 using Chi-square and ANOVA. Results: The difference between two groups was not statistically significant regarding demographic and basic variables. The incidence of bradycardia in both groups was respectively (90.7 percent vs. 17.3 percent, heart rate less than 60 beats/minute (40 percent vs. 13.3 percent, hypotension (76 percent vs. 32 percent and blood pressure less than 90 mmHg was (28 percent vs. 8 percent. Accordingly, the differences between both groups were statistically significant (P > 0.001. Conclusions: The preventive impact of topical xylocaine upon oculocardiac reflex in ophthalmological surgeries such as retinal detachment and vitrectomy with scleral buckling under general anesthesia was less effective than that of atropine injection. Therefore, to avoid this reflex in high-risk patients, injecting atropine would be safer.

  20. Comparison of metaraminol, phenylephrine and ephedrine in prophylaxis and treatment of hypotension in cesarean section under spinal anesthesia

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    Fábio Farias de Aragão


    Full Text Available Maternal hypotension is a common complication after spinal anesthesia for cesarean section, with deleterious effects on the fetus and mother. Among the strategies aimed at minimizing the effects of hypotension, vasopressor administration is the most efficient. The aim of this study was to compare the efficacy of phenylephrine, metaraminol, and ephedrine in the prevention and treatment of hypotension after spinal anesthesia for cesarean section. Ninety pregnant women, not in labor, undergoing cesarean section were randomized into three groups to receive a bolus followed by continuous infusion of vasopressor as follows: phenylephrine group (50 μg + 50 μg/min; metaraminol group (0.25 mg + 0.25 mg/min; ephedrine group (4 mg + 4 mg/min. Infusion dose was doubled when systolic blood pressure decreased to 80% of baseline and a bolus was given when systolic blood pressure decreased below 80%. The infusion dose was divided in half when systolic blood pressure increased to 120% and was stopped when it became higher. The incidence of hypotension, nausea and vomiting, reactive hypertension, bradycardia, tachycardia, Apgar scores, and arterial cord blood gases were assessed at the 1st and 5th minutes. There was no difference in the incidence of hypotension, bradycardia, reactive hypertension, infusion discontinuation, atropine administration or Apgar scores. Rescue boluses were higher only in the ephedrine group compared to metaraminol group. The incidence of nausea and vomiting and fetal acidosis were greater in the ephedrine group. The three drugs were effective in preventing hypotension; however, fetal effects were more frequent in the ephedrine group, although transient.


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    Sarada Devi


    Full Text Available This study was undertaken to evaluate the effect of a bolus dose of dexmedetomidine on haemodynamic, recovery responses and airway reflexes during extubation. MATERIAL AND METHODS Sixty patients aged 20-45 yrs. of either sex of ASA grade I/II scheduled for elective general surgical, ENT, orthopaedics and gynaecological surgeries were studied after randomisation into two groups; 5 minutes before anticipated end of surgery, group A and B received either dexmedetomidine 0.5 µg/kg or placebo (Saline respectively intravenously over 2 minutes. Anaesthesia technique was standardised for both groups. Heart rate, systolic, diastolic, mean arterial pressures were recorded at the start of a bolus drug injection and thereafter 1, 2 and 3 minutes after injection during extubation; at 1, 3, 5 minutes after extubation for 15 minutes. Quality of extubation was evaluated immediately after extubation based on cough using a 5-point rating score. Postoperative sedation was evaluated on a 6-point scale (Ramsay sedation scale. Side effects like laryngospasm, bronchospasm, respiratory depression, desaturation, vomiting, hypotension, bradycardia and undue sedation were noted. RESULTS Heart rate, systolic, diastolic, mean arterial pressure were significantly lower in study group. Extubation quality score in majority of cases was score 1 in study group and score 3 in control group. Sedation score in most of the cases was 3 in study group and 2 in control group. Bradycardia and hypotension were more in study group. Vomiting incidence was comparable in both the groups. CONCLUSION Our study concludes that single dose of dexmedetomidine 0.5 µg/kg administered 5 minutes before extubation attenuates the haemodynamic and airway reflexes during emergence from anaesthesia without causing undue sedation.

  2. The myocardial protective effect of dexmedetomidine in high-risk patients undergoing aortic vascular surgery

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    Rabie Soliman


    Full Text Available Objective: The aim of the study was to assess the effect of dexmedetomidine in high-risk patients undergoing aortic vascular surgery. Design: A randomized prospective study. Setting: Cairo University, Egypt. Materials and Methods: The study included 150 patients undergoing aortic vascular surgery. Intervention: The patients were classified into two groups (n = 75. Group D: The patients received a loading dose of 1 μg/kg dexmedetomidine over 15 min before induction and maintained as an infusion of 0.3 μg/kg/h to the end of the procedure. Group C: The patients received an equal volume of normal saline. The medication was prepared by the nursing staff and given to anesthetist blindly. Measurements: The monitors included the heart rate, mean arterial blood pressure, central venous pressure, electrocardiogram (ECG, serum troponin I level, end-tidal sevoflurane, and total dose of morphine in addition transthoracic echocardiography to the postoperative in cases with elevated serum troponin I level. Main Results: The dexmedetomidine decreased heart rate and minimized the changes in blood pressure compared to control group (P < 0.05. Furthermore, it decreased the incidence of myocardial ischemia reflected by troponin I level, ECG changes, and the development of new regional wall motion abnormalities (P < 0.05. Dexmedetomidine decreased the requirement for nitroglycerin and norepinephrine compared to control group (P < 0.05. The incidence of hypotension and bradycardia was significantly higher with dexmedetomidine (P < 0.05. Conclusion: The dexmedetomidine is safe and effective in patients undergoing aortic vascular surgery. It decreases the changes in heart rate and blood pressure during the procedures. It provides cardiac protection in high-risk patients reflected by decreasing the incidence of myocardial ischemia and serum level of troponin. The main side effects of dexmedetomidine were hypotension and bradycardia.

  3. Ivabradine: Do the Benefits Outweigh the Risks? (United States)

    Alshammari, Thamir M


    Ivabradine is a selective I: f current inhibitor that is used to lower the heart rate (HR) of patients with angina and/or heart failure. It is approved for use in several countries, including the United Kingdom, Australia, Saudi Arabia, and the United States. The drug was studied in several clinical trials, and it exhibited beneficial effects on the approved indicators. However, there are some concerns with the safety profile of this drug, especially its effect in reducing HR and causing severe bradycardia. Therefore, the current review assessed the benefit-risk balance of ivabradine. A literature review of the major published studies that assessed the efficacy and safety of ivabradine was performed. The online VigiBase adverse drug reaction (ADR) reporting system was also accessed to investigate reports associated with this drug. A full benefit-risk assessment was performed using the collected data from the above-mentioned resources. Most of the reviewed studies concluded that ivabradine exerted beneficial effects with a tolerable safety profile. Specifically, a favorable benefit-risk profile was found when ivabradine was used for patients with an HR ≥70 beats per minute. Reports revealed that the most common ADR was bradycardia, which was expected. Other safety risks or ADRs were comparable to other prescribed drugs. This review presents an up-to-date analysis of ivabradine from the latest literature and reports. These studies suggest that ivabradine exhibits an acceptable and favorable benefit-risk profile, and this drug should be considered as a viable option in patients with angina pectoris and chronic heart failure.

  4. Acute ivabradine treatment reduces heart rate without increasing atrial fibrillation inducibility irrespective of underlying vagal activity in dogs. (United States)

    Uemura, Kazunori; Inagaki, Masashi; Zheng, Can; Kawada, Toru; Li, Meihua; Fukumitsu, Masafumi; Sugimachi, Masaru


    Ivabradine, a bradycardic agent, has been shown to stably reduce patient's heart rate (HR) in the setting of acute cardiac care. However, an association between atrial fibrillation (AF) risk and acute ivabradine treatment remains a controversial clinical issue, and has not been thoroughly investigated. Bradycardia and abnormal atrial refractoriness induced by ivabradine treatment may enhance vulnerability to AF induction, especially when vagal nerve is concurrently activated. We aimed to experimentally investigate the effects of acute ivabradine treatment with/without concurrent vagal activation on AF inducibility. In 16 anesthetized dogs, cervical vagal nerves were prepared for electrical stimulation (VS). AF induction rate (AFIR) was determined by atrial burst pacing. HR, atrial action potential duration (APD), atrial effective refractory period (ERP), and AFIR were obtained consecutively at baseline, during delivery of VS (VS alone), after intravenous injection of ivabradine 0.5 mg/kg (n = 8, ivabradine group) or saline (n = 8, saline group), and again during VS delivery (drug+VS). In the ivabradine group, ivabradine alone significantly lowered HR compared to baseline, while ivabradine+VS significantly lowered HR compared to VS alone. Contrary to expectations, there were no significant differences in trends of APD, temporal dispersion of APD, ERP, and AFIR between ivabradine and saline groups. Irrespective of whether ivabradine or saline was injected, VS significantly shortened APD and ERP, and increased AFIR. Interestingly, although bradycardia in response to ivabradine injection was more intense than that to VS alone, AFIR was significantly lower after ivabradine injection than during VS alone. We conclude that, despite its intense bradycardic effect, acute ivabradine treatment does not increase AF inducibility irrespective of underlying vagal activity. This study may constitute support for the safety of using ivabradine in the setting of acute cardiac

  5. Comparison of Postoperative Analgesic Effects of Thoracic Epidural Morphine and Fentanyl

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    Gönül Sağıroğlu


    Full Text Available Objective: In our study, we aimed to compare epidural morphine and fentanyl analgesia and the side effects in post-thoracotomy pain management. Material and Methods: Forty patients, planned for elective thoracotomy were included. Bupivacain- morphine was administered through an epidural catheter to the patients in Group-M while bupivacain-fentanyl was given in Group-F. Pain assessment was carried out with the Visual Analogue Scale (VAS and VAS-I and VAS-II were assessed in 0, 4, 16 and 24th hour in the postoperative unit. Adverse effects were recorded after the 24th hour. Statistical analyses were performed by using Two-sample independent-t test, Mann Whitney-U test, Wilcoxon-signed ranks test and Pearson chi-squared tests. Results: Although, the VAS-I and VAS-II scores were lower in Group-M than Group-F, the difference was not significant statistically (p>0.05. When other hours were compared with initial states, beginning from the 4th hour, in both groups there was a statistically significant drop in VAS-I and VAS-II scores at all times (p<0.001. Comparing the complications between the groups, in Group-M nausea-vomiting (p<0.015 and bradycardia (p<0.012 were found significantly more frequently than in Group-F. Conclusion: We concluded that, in pain management after thoracic surgery, either morphine or fentanyl may be chosen in thoracal epidural analgesia but, especially in the early postoperative hours, close follow-up is necessary due to the risk of bradycardia development.

  6. Regional haemodynamic effects of noradrenaline injected into the hypothalamic paraventricular nuclei of conscious, unrestrained rats: possible mechanisms of action. (United States)

    Bachelard, H; Harland, D; Gardiner, S M; Kemp, P A; Bennett, T


    The cardiovascular effects of noradrenaline bilaterally injected into the hypothalamic paraventricular nuclei were investigated in conscious, unrestrained Long-Evans rats and homozygous, vasopressin-deficient Brattleboro rats, chronically instrumented with pulsed Doppler probes for measurement of regional haemodynamics. In Long-Evans rats, incremental doses of noradrenaline (0.01-10 nmol) caused dose-related increases in blood pressure and a substantial, dose-related, superior mesenteric vasoconstriction. These changes were accompanied by bradycardia and reductions in renal and hind-quarter vascular conductances. In Brattleboro rats, noradrenaline (10 nmol) had no effect on blood pressure, heart rate, or renal or superior mesenteric vascular conductances. However, there was a slight vasodilatation in the vascular bed of the hindquarters. In Long-Evans rats, intravenous pretreatment with phentolamine had no effect on the bradycardia but partly inhibited the pressor response to noradrenaline injected into the paraventricular nuclei. These effects were associated with a smaller superior mesenteric vasoconstriction and an abolition of the vasoconstriction in the hindquarters. Combined intravenous pretreatment with phentolamine and propranolol had no effect on the heart rate or pressor responses to noradrenaline injected into the paraventricular nuclei, but reduced the superior mesenteric vasoconstriction, potentiated the vasoconstriction in the hindquarters and eliminated the renal vasoconstriction. These results suggest that, in untreated Long-Evans rats, alpha-adrenoceptor-mediated constriction in the mesenteric vascular bed and beta-adrenoceptor-mediated dilatation in the vascular bed of the hindquarters have important influences on the pressor response to noradrenaline injected into the paraventricular nuclei. In the presence of the vasopressin V1-receptor antagonist, d(CH2)5[Tyr(Et)]DAVP, the pressor and heart rate responses to noradrenaline injected into the

  7. 河北省自行车运动员安静心电图特征分析%Analysis of Electrocardiogram (ECG) of Cyclist in Hebei Province

    Institute of Scientific and Technical Information of China (English)

    周君一; 崔维冬; 管亚楠; 陈旭; 高峰


    To explore quiet electrocardiogram characteristics of cyclists in different sports level , we chose five level 1 and twelve training cyclists from bicycle sports management center in Hebei province to do electrocardiogram test in rest state. Results: The average?resting heart rate?of bicycle athletes in level 1 was 50.8+9.42/min,?the average?resting heart rate?of training?athletes was 59.8+4.12/min. There was significant difference of heart rate in resting between bicycle athletes in different training level. The overall incidence of sinus bradycardia was 59%. The average incidence of sinus bradycardia of bicycle athletes in level 1 was 80%, and the average incidence of sinus bradycardia of cyclists in training was 50%. The difference was significant. To compare the test results of athletes with the general ECG standard , the electrocardiogram QRS complex voltage increased, the heart rate reduced, the QTc value increased, and ST segment increased. Other indicators indexes were in the normal range. The ECG changes indicates electrocardiogram physiological adaptation of athlete and were a sign of better heart reserves. Electrocardiogram (ECG) abnormal changes of cyclists mainly included: QT abnormal interphase (long QT, QT) in 5 cases, accounted for 29.4%, ventricular pre-excitation syndrome in 2cases , and 2 cases of starboard electrical axis. To strengthen the electrocardiogram (ECG) monitoring and medical supervision of athletes is necessary.%对河北省体育局自行运动管理中心的5名一级和12名集训自行车运动员进行安静心电图测试,探索不同运动水平自行车运动员的安静心电图特征。结果显示:一级自行车运动员平均安静心率为50.8±9.42次/min,集训运动员平均安静心率为59.8±4.12次/min,不同运动水平运动员之间心率具有显著性差异;整体窦性心动过缓发生率为59%,一级水平运动员心动过缓发生率为80%,集训水平运动员心动过缓发生率为50%

  8. Ictal ECG changes in temporal lobe epilepsy Alterações eletrocardiográficas ictais em epilepsia do lobo temporal

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    L.M. Li


    Full Text Available Changes in cardiac rhythm may occur during epileptic seizures and this has been suggested as a possible mechanism for sudden unexpected death amongst patients with chronic epilepsy (SUDEP. We have studied ECG changes during 61 complex partial seizures of temporal lobe origin in 20 patients. Tachycardia was observed in 24/61 (39% and bradycardia in 3/61 (5%. The mean and median tachycardia rate was 139 and 140 beats/min (range 120-180. The longest R-R interval observed was 9 seconds. No difference was found in regard to the lateralisation of seizures and cardiac arrhytmia. One of the patients with bradycardia was fitted with a demand cardiac pacemaker, which appeared to decrease the number of his falls. In conclusion, ictal cardiac changes which may be seen in temporal lobe epilepsy (TLE are sinus tachycardia and occasionally sinus bradycardia. Patients presenting vague complains suggestive of either TLE or cardiac dysrhythmia, simultaneous monitoring with EEG/ECG is required, and if the episodes are frequent, video-EEG should be considered. Further studies on this subject are warranted as this may shed some light on possible mechanisms for SUDEP.Alterações no ritmo cardíaco podem ocorrer durante crises epilépticas. Estas alterações têm sido sugeridas como possível mecanismo para explicar morte súbita em pacientes com epilepsia crônica. Analisamos o eltrocardiograma (ECG em 61 crises parciais complexas do lobo temporal de 20 pacientes. Taquicardia foi observada em 24/61 (39% e bradicardia em 3/61 (5%. A média e a mediana da taquicardia foram 139 e 140 batimentos por minuto (variando de 120-180. O intervalo R-R mais longo foi 9 segundos. Não houve diferença em relação a lateralisação das crises e alteração do ritmo cardíaco. Um paciente com bradicardia recebeu marcapasso de demanda, com diminuição importante das suas quedas durante as crises. Em conclusão, as alterações cardíacas ictais em crises do lobo temporal mais

  9. Safety of cardiac magnetic resonance and contrast angiography for neonates and small infants: a 10-year single-institution experience

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    Rangamani, Sheela; Li, Ling; Harvey, Lisa; Fletcher, Scott E.; Danford, David A.; Kutty, Shelby [University of Nebraska College of Medicine/Creighton University School of Medicine, Joint Division of Pediatric Cardiology, Omaha, NE (United States); Varghese, Joby [Children' s Hospital and Medical Center, Division of Pediatric Cardiac Anesthesia, Omaha, NE (United States); Hammel, James M.; Duncan, Kim F. [Children' s Hospital and Medical Center, Division of Cardiothoracic Surgery, Omaha, NE (United States)


    With increasing applications of cardiac magnetic resonance (CMR) and magnetic resonance angiography (MRA) for evaluation of congenital heart disease (CHD), safety of this technology in the very young is of particular interest. We report our 10-year experience with CMR in neonates and small infants with particular focus on the safety profile and incidence of adverse events (AEs). We reviewed clinical, anesthesia and nursing records of all children {<=}120 days of age who underwent CMR. We recorded variables including cardiac diagnosis, study duration, anesthesia type and agents, prostaglandin E1 (PGE1) dependence and gadolinium (Gd) use. Serially recorded temperature, systemic saturation (SpO{sub 2}) and cardiac rhythm were analyzed. Primary outcome measure was any AE during or <24 h after the procedure, including minor AEs such as hypothermia (axillary temperature {<=}95 F), desaturation (SpO{sub 2} drop {>=}10% below baseline) and bradycardia (heart rate {<=}100 bpm). Secondary outcome measure was unplanned overnight hospitalization of outpatients. Children (n = 143; 74 boys, 69 girls) had a median age of 6 days (1-117), and 98 were {<=}30 days at the time of CMR. The median weight was 3.4 kg (1.4-6 kg) and body surface area 0.22 m{sup 2} (0.13-0.32 m{sup 2}). There were 118 (83%) inpatients (108 receiving intensive care) and 25 (17%) outpatients. Indications for CMR were assessment of aortic arch (n = 57), complex CHD (n = 41), pulmonary veins (n = 15), vascular ring (n = 8), intracardiac mass (n = 8), pulmonary artery (n = 7), ventricular volume (n = 4), and systemic veins (n = 3). CMR was performed using a 1.5-T scanner and a commercially available coil. CMR utilized general anesthesia (GA) in 86 children, deep sedation (DS) in 50 and comforting methods in seven. MRA was performed in 136 children. Fifty-nine children were PGE1-dependent and 39 had single-ventricle circulation. Among children on PGE1, 43 (73%) had GA and 10 (17%) had DS. Twelve children (9%) had


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    Niranjan Kumar Verma


    Full Text Available BACKGROUND Laparoscopic cholecystectomies are generally performed under general anaesthesia. Trials for spinal anaesthesia were not satisfactory. My experience on 100 cases with a modified technique provided very good results, where Bupivacaine and Clonidine were administered by subarachnoid route combined with peritoneal insufflation and local infiltration of Ropivacaine. METHOD One hundred ASI grade 1 and grade 2 patients undergoing elective laparoscopic cholecystectomy opting for spinal anaesthesia were given 1 mL (150 mcg of clonidine in L1-L2 interspace followed by 3 mL (15 mg of 0.5% heavy bupivacaine in the same interspace by separate syringes, 15 degrees head down tilt, intra-peritoneal insufflation of 0.5% Ropivacaine just after pneumoperitoneum and cannula insertion and lastly local infiltration of 0.5% Ropivacaine 2 mL at each incision at the time of skin closure. Preemptive 10-15 mg of Mephentermine IM was given to each patient. Recordings of vital parameters, pain experienced by patients, especially excruciating shoulder pain, any difficulty experienced by surgeons, need for analgesia, level of consciousness, respiratory depression, hypotension, bradycardia, pruritus were recorded at frequent intervals during operation and later in the ICU for prompt managements. RESULTS None of the patients experienced any pain in the peri- and post-operative period, analgesia was excellent for 12-16 hours postoperatively. No respiratory depression, severe bradycardia, hypotension or pruritus was noticed. Incidence of post-operative nausea and vomiting were negligible. CONCLUSION Clonidine as adjuvant with hyperbaric Bupivacaine in spinal anaesthesia combined with intraperitoneal infiltration of 20 mL of 0.5% Ropivacaine just after insertion of cannula through an irrigation cannula and 2 mL of 0.5% Ropivacaine injected at each port site at the time of skin stitches, when given in proper way can be a very good alternative to general anaesthesia for

  11. Assessment of electrocardiography, echocardiography, and heart rate variability in dynamic and static type athletes

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    Ataei A


    Full Text Available Mehrnoush Toufan,1 Babak Kazemi,1 Fariborz Akbarzadeh,1 Amin Ataei,1 Majid Khalili21Cardiovascular Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; 2Azerbaijan National Academy of Sciences, Baku, AzerbaijanBackground: Over the last two decades, morphological cardiac changes induced by athletic conditioning have been of great interest. Therefore, several studies have been orchestrated to delineate electrocardiography (ECG, echocardiography, and heart rate variability (HRV findings in athletes.Purpose: To assess the ECG, echocardiography, and HRV in a group of dynamic and static type athletes.Methods: Fifty professional athletes (20 static and 30 dynamic exercise athletes and 50 healthy nonathletes (control group were recruited. Standard 12-lead ECG and transthoracic echocardiography was performed on all athletes and the control group. Through echocardiography, variables including left ventricular (LV end-diastolic/systolic diameter, LV mass, and left atrial volume index were measured. In addition, both the athletes and the control group underwent ECG Holter monitoring for 15 minutes and several parameters related to HRV (time and frequency domain were recorded.Results: The most common ECG abnormalities among the athletes were sinus bradycardia and incomplete right bundle branch block. LV end-diastolic diameter and left atrial volume index were significantly greater in the dynamic athletes (P < 0.001. LV end-systolic diameter was significantly lower in the static group (P < 0.001. LV mass of the dynamic and static athletes was significantly greater than that of the controls (P < 0.001. Among the ECG Holter monitoring findings, the dynamic athletes had lower systolic blood pressure than the controls (P = 0.01. Heart rate was lowest in the control group (P < 0.001.Conclusion: The most common ECG abnormalities among adolescent Iranian athletes were sinus bradycardia and incomplete right bundle branch block. Static exercise seemed

  12. Intoxication due to Papaver rhoeas (Corn Poppy: Five Case Reports

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    Yahya Kemal Günaydın


    Full Text Available Introduction. In this paper, we aimed to present five Papaver rhoeas intoxication cases, which is very rare in the literature. Case 1. A 35-year-old female patient was admitted to our emergency room with the complaints of nausea, restlessness, and dyspnea developing 3 hours after eating Papaver rhoeas. On physical examination, her general condition was moderate; she was conscious and the vital findings were normal. The pupils were myotic. She was transferred to the toxicology intensive care unit as she experienced a generalized tonic clonic seizure lasting for three minutes. Case 2. A 41-year-old female patient was brought to our emergency room by 112 ambulance as she had contractions in her arms and legs, unconsciousness, and foam coming from her mouth two hours after Papaver rhoeas ingestion. On physical examination, she was confused, the pupils were myotic, and she was tachycardic. Arterial blood gases analysis revealed lactic acidosis. Case 3. A 38-year-old female patient was admitted to our emergency room with complaints of nausea and vomiting two hours after ingestion of Papaver rhoeas. Her physical examination and tests were normal. Case 4. A 34-year-old male patient was admitted to our emergency room with complaints of numbness and loss of power in his arms and legs one hour after Papaver rhoeas ingestion. He was hospitalized at the toxicology intensive care unit for follow-up and treatment. Dyspnea and bradycardia developed on the follow-up. The oxygen saturation without oxygen support was 90%. ECG revealed sinus bradycardia. The cardiac enzymes did not increase. Case 5. A 42-year-old female patient was brought to our emergency room by 112 ambulance with contractions in her arms and legs and unconsciousness two hours after Papaver rhoeas ingestion. On her physical examination, she was confused and the pupils were myotic. Arterial blood gases analysis revealed lactic acidosis. Conclusion. All patients were followed up for a few days and

  13. Comparação da anestesia geral e bloqueio do plexo cervical superficial em tireoidectomias parciais Comparison between general anesthesia and superficial cervical plexus block in partial thyroidectomies

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    Rui Celso Martins Mamede


    Full Text Available Tireoidectomia sob efeito de bloqueio do plexo cervical superficial (BPCS tem sofrido resistência. OBJETIVO: Comparar variáveis cirúrgicas e anestésicas, custos do tratamento e grau de satisfação de pacientes submetidos à hemitireoidectomia sob efeito de anestesia geral e BPCS. CASUÍSTICA E MÉTODOS: Foram 21 pacientes submetidos à anestesia geral (AG e outro tanto ao BPCS. Após sedação, no grupo com BPCS, usou-se marcaína com vasoconstritor, e quando necessário, lidocaína a 2% com vasoconstritor. Sedação intra-operatória com diazepam endovenoso e metoprolol para controle da PA e FC eram administradas quando necessário. Usou-se anestesia geral (AG segundo padronização do serviço. RESULTADOS: Foram significantes (pThyroidectomy under the effect of superficial cervical plexus block (SCPB has met resistance. AIM: to compare variables in patients submitted to hemithyroidectomy under the effect of general anesthesia (GA and SCPB. CASE REPORT AND METHODS: GA was used in 21 patients, and SCPB was used in another 21 patients. Following sedation, marcaine 0.5% with vasoconstrictor was used in the SCPB group. Intraoperative sedation with diazepam and metoprolol to control arterial pressure and cardiac frequency was given as needed. GA followed the standard method in the unit. RESULTS: We found significant results (p<0.05, Student’s t-test for surgery time (GA - 111.4 min; SCPB - 125.5 min, anesthesia time (GA - 154.1 min; SCPB - 488.6 min, time in the surgery room (GA - 15 min; SCPB - 1 min, treatment costs (GA - R$203.2; SCPB - R$87.4, presence of bradycardia (GA - 0; SCPB - 23.8% and laryngotracheal injury (GA - 51; SCPB - 0 %. We also found the following non-significant results: hospitalization time (GA - 17.3; SCPB - 15.1 hours; bleeding volume (GA - 41,9 g; SCPB - 47.6 g, size of the operative specimen (GA - 52.1 cm3; SCPB - 93.69 cm3 and patient satisfaction level (GA - 3.8; SCPB - 3.9. CONCLUSION: Although the incidence of

  14. Electrophysiological effects of cetirizine, astemizole and D-sotalol in a canine model of long QT syndrome. (United States)

    Weissenburger, J; Noyer, M; Cheymol, G; Jaillon, P


    Observations of torsades de pointes during therapy with terfenadine and astemizole has raised concern about the cardiac safety of non-sedating H1-antagonist agents. We compared cetirizine, another compound of that class, to D-sotalol and to astemizole in a model of acquired long QT syndrome. Open-chest surgery was performed in adult beagle dogs anaesthetized with halothane and thiopental. Bradycardia was produced with beta-adrenergic blockade and sinus node crush. Four left ventricular intramyocardial unipolar monophasic action potentials (MAP) were recorded during atrial pacing at basic cycle lengths (BCL) 400-1500 msec, before and during three successive 1-h drug infusions (0.14, 0.45 and 1.4 mg/kg/h for astemizole and cetirizine and 1.1, 2.2 and 4.5 mg/kg/h for D-sotalol). Dose- and bradycardia-dependent prolongations of MAP duration (MAPD) were produced by D-sotalol (P < 0.001) and astemizole (P < 0.001) but not by cetirizine. At BCL 1500 ms, the three infusions of astemizole prolonged endocardial MAPD from 323 +/- 8 msec (mean +/- SE) at baseline to 343 +/- 10, 379 +/- 13 and 468 +/- 26 msec, respectively (n = 9). Sotalol prolonged that MAPD from 339 +/- 6 msec to 377 +/- 7, 444 +/- 15 and 485 +/- 24 msec (n = 7). In contrast, cetirizine did not prolong MAPD: 341 +/- 8 msec at baseline Vs 330 +/- 8, 324 +/- 9 and 323 +/- 11 msec (n = 9). Drug-induced increase in transmural dispersion reached +79 +/- 19 msec after astemizole, +59 +/- 21 msec after D-sotalol and only +7 +/- 11 msec after cetirizine. Runs of ventricular tachycardias and torsades de pointes occurred during dose three of astemizole (5/9 dogs) and D-sotalol (4/7 dogs) but never during cetirizine. In the present model, astemizole and D-sotalol but not cetirizine prolonged MAPD and transmural dispersions of repolarization and produced torsades de pointes. These results suggest that the halothane-anaesthetized bradycardic dog could be a valuable model to discriminate drugs for their class III effects

  15. Analysis of related factors of abnormal graphics in fetal heart monitoring at the birth process%产程中胎心监护异常图形相关因素分析

    Institute of Scientific and Technical Information of China (English)



    Objective:To explore the relationship between the abnormal graphics in fetal heart monitoring at the birth process and perinatal outcome.Methods:300 cases of pregnant women were selected.They were given intrapartum fetal heart monitoring,we observed,record and analyzed monitoring results.Results:During production process,124 cases had CST score and graphic abnormality,176 cases were normal,in the graphic abnormalities,the incidence of fetal distress,neonatal asphyxia was obviously higher than that in the control group(P<0.05).Vaginal operation labor,cesarean section rate were significantly higher than the control group(P<0.05).Common types were FHR tachycardia,FHR bradycardia,severe variable deceleration,late deceleration, FHR flat orderly.Conclusion:During production process,FHR tachycardia,FHR bradycardia,severe variable deceleration,late deceleration,FHR flat were closely related with fetal distress and neonatal asphyxia.They should be pay more attention,in order to discover and handle timely.%目的:探讨产程中异常胎心监护图形与围产儿结局的关系。方法:收治产妇300例,行产程胎心监护,进行观察、记录和分析。结果:产程中CST评分及图形异常124例,正常176例,图形异常胎儿宫内窘迫、新生儿窒息的发生率明显高于对照组(P<0.05),阴道手术产、剖宫产率明显高于对照组(P<0.05)。常见类型依次为 FHR 过速、FHR 过缓、重度变化减速、晚期减速、FHR 平直。结论:产程中 FHR 过速、FHR 过缓、重度变化减速、迟发减速、FHR平直与胎儿宫内窘迫及新生儿窒息的发生关系密切,应予以重视,及时发现和处理。

  16. 自身抗体相关性先天性心脏传导阻滞1例报告%One case report of autoantibody-associated congenital heart block

    Institute of Scientific and Technical Information of China (English)

    冯宗太; 杨晓路; 杨祖铭; 蔡燕; 王三南


    ObjectiveTo explore the pathogenesis, clinical manifestations, diagnosis, and treatment of autoanti-body-associated congenital heart block.MethodsThe clinical data of one child with autoantibody-associated congenital heart block was retrospectively analyzed.ResultsIn 24 week gestation, fetal bradycardia had been found by routine fetal echocar-diography. After birth, the anti-SSA/Ro antibodies and anti-SSB/La antibodies were positive in both infant and her mother. The diagnosis of autoantibody-associated congenital heart block was conifrmed. Intravenous immunoglobulin at 1 g/kg was adminis-trated. At 6 months follow-up, the electrocardiogram suggested type I second degree atrioventricular block.ConclusionIn the fetus or neonates found to have bradycardia and excluded the cardiac structural abnormalities, the autoimmune antibody should been tested and early intervention should been promoted.%目的:探讨自身抗体相关性先天性心脏传导阻滞的发病机制,临床表现及诊断和治疗。方法回顾性分析1例自身抗体相关性先天性心脏传导阻滞患儿的临床资料。结果患儿于24周胎龄时即在超声检查中发现胎儿心动过缓,出生后检测患儿及其母亲的抗SSA/Ro抗体和抗SSB/La抗体均为阳性,确诊为自身抗体相关性先天性心脏传导阻滞,予静脉注射免疫球蛋白1 g/kg治疗。6月龄随访提示仍为Ⅱ度Ⅰ型房室传导阻滞。结论当发现胎儿或新生儿心动过缓且排除心脏结构异常时,应完善自身免疫抗体检查并尽早干预。

  17. Super, red palm and palm oleins improve the blood pressure, heart size, aortic media thickness and lipid profile in spontaneously hypertensive rats.

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    Chee-Meng Boon

    Full Text Available BACKGROUND: Oleic acid has been shown to lower high blood pressure and provide cardiovascular protection. Curiosity arises as to whether super olein (SO, red palm olein (RPO and palm olein (PO, which have high oleic acid content, are able to prevent the development of hypertension. METHODOLOGY/PRINCIPAL FINDINGS: Four-week-old male spontaneously hypertensive rats (SHR and Wistar-Kyoto (WKY rats were fed 15% SO, RPO or PO supplemented diet for 15 weeks. After 15 weeks of treatment, the systolic blood pressure (SBP of SHR treated with SO, RPO and PO were 158.4±5.0 mmHg (p<0.001, 178.9±2.7 mmHg (p<0.001 and 167.7±2.1 mmHg (p<0.001, respectively, compared with SHR controls (220.9±1.5 mmHg. Bradycardia was observed with SO and PO. In contrast, the SBP and heart rate of treated WKY rats were not different from those of WKY controls. The SO and PO significantly reduced the increased heart size and thoracic aortic media thickness observed in untreated SHR but RPO reduced only the latter. No such differences, however, were observed between the treated and untreated WKY rats. Oil Red O enface staining of thoracic-abdominal aorta did not show any lipid deposition in all treated rats. The SO and RPO significantly raised serum alkaline phosphatase levels in the SHR while body weight and renal biochemical indices were unaltered in both strains. Serum lipid profiles of treated SHR and WKY rats were unchanged, with the exception of a significant reduction in LDL-C level and total cholesterol/HDL ratio (atherogenic index in SO and RPO treated SHR compared with untreated SHR. CONCLUSION: The SO, RPO and PO attenuate the rise in blood pressure in SHR, accompanied by bradycardia and heart size reduction with SO and PO, and aortic media thickness reduction with SO, RPO and PO. The SO and RPO are antiatherogenic in nature by improving blood lipid profiles in SHR.

  18. Time-dependent effects of training on cardiovascular control in spontaneously hypertensive rats: role for brain oxidative stress and inflammation and baroreflex sensitivity.

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    Gustavo S Masson

    Full Text Available Baroreflex dysfunction, oxidative stress and inflammation, important hallmarks of hypertension, are attenuated by exercise training. In this study, we investigated the relationships and time-course changes of cardiovascular parameters, pro-inflammatory cytokines and pro-oxidant profiles within the hypothalamic paraventricular nucleus of the spontaneously hypertensive rats (SHR. Basal values and variability of arterial pressure and heart rate and baroreflex sensitivity were measured in trained (T, low-intensity treadmill training and sedentary (S SHR at weeks 0, 1, 2, 4 and 8. Paraventricular nucleus was used to determine reactive oxygen species (dihydroethidium oxidation products, HPLC, NADPH oxidase subunits and pro-inflammatory cytokines expression (Real time PCR, p38 MAPK and ERK1/2 expression (Western blotting, NF-κB content (electrophoretic mobility shift assay and cytokines immunofluorescence. SHR-S vs. WKY-S (Wistar Kyoto rats as time control showed increased mean arterial pressure (172±3 mmHg, pressure variability and heart rate (358±7 b/min, decreased baroreflex sensitivity and heart rate variability, increased p47phox and reactive oxygen species production, elevated NF-κB activity and increased TNF-α and IL-6 expression within the paraventricular nucleus of hypothalamus. Two weeks of training reversed all hypothalamic changes, reduced ERK1/2 phosphorylation and normalized baroreflex sensitivity (4.04±0.31 vs. 2.31±0.19 b/min/mmHg in SHR-S. These responses were followed by increased vagal component of heart rate variability (1.9-fold and resting bradycardia (-13% at the 4th week, and, by reduced vasomotor component of pressure variability (-28% and decreased mean arterial pressure (-7% only at the 8th week of training. Our findings indicate that independent of the high pressure levels in SHR, training promptly restores baroreflex function by disrupting the positive feedback between high oxidative stress and increased pro

  19. A prospective randomised controlled trial to determine the early and late reactions after the use of iopamidol 340 (Niopam{sup TM}) and iomeprol 350 (Iomeron[reg]) in cardiac catheterisation

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    Vijayalakshmi, Kunadian [Department of Cardiology, James Cook University Hospital, Marton Road, Middlesbrough TS4 3BW (United Kingdom)]. E-mail:; Kunadian, Babu [Department of Cardiology, James Cook University Hospital, Marton Road, Middlesbrough TS4 3BW (United Kingdom); Wright, Robert A. [Department of Cardiology, James Cook University Hospital, Marton Road, Middlesbrough TS4 3BW (United Kingdom); Hall, James A. [Department of Cardiology, James Cook University Hospital, Marton Road, Middlesbrough TS4 3BW (United Kingdom); Stewart, Michael J. [Department of Cardiology, James Cook University Hospital, Marton Road, Middlesbrough TS4 3BW (United Kingdom); Davies, Adrian [Department of Cardiology, James Cook University Hospital, Marton Road, Middlesbrough TS4 3BW (United Kingdom); Sutton, Andrew [Department of Cardiology, James Cook University Hospital, Marton Road, Middlesbrough TS4 3BW (United Kingdom); Belder, Mark A. de [Department of Cardiology, James Cook University Hospital, Marton Road, Middlesbrough TS4 3BW (United Kingdom)]. E-mail:


    A new generation of intravascular contrast agents, the non-ionic monomers have safety profiles that are superior to those of older ionic compounds. There are, however, significant differences between these agents. Aim: The aim of this study was to determine the incidence of early (<24 h) and late (>24 h to 7 days) reactions to two non-ionic contrast agents currently used during cardiac catheterisation: iopamidol 340 (Niopam{sup TM} Bracco UK Ltd.) and iomeprol 350 (Iomeron[reg] Bracco UK Ltd.). Methods: This was a prospective, randomised, double blinded trial. One thousand nine hundred and eighty-five patients undergoing cardiac catheterisation received one of the following contrast agents on a weekly basis: iopamidol 340 (Niopam{sup TM}) and iomeprol 350 (Iomeron[reg]). Reactions that were possibly related to the contrast agents were recorded on predefined data collection forms during the first 24 h of the procedure (early reaction) and after 24 h to 7 days (late reaction) by means of a questionnaire. Results: The baseline characteristics were matched in both the groups. There was no significant difference in the incidence of heat sensation experienced between the two groups (p = 0.1). Early non-heat reactions occurred in 2.7% of patients receiving iopamidol 340 (Niopam{sup TM}) and 4% of those receiving iomeprol 350 (Iomeron[reg]) (p = 0.1). Significant electrocardiographic changes were recorded in 1.7% of patients who received iopamidol 340 (Niopam{sup TM}), and 1% of those who received iomeprol 350 (Iomeron[reg]) (p = 0.2). Bradycardia occurred more frequently in the iopamidol 350 group (0.8%) compared to the iomeprol 350 group (0.1%) p = 0.02. Late reactions occurred in 16.2% of those receiving iopamidol 340 (Niopam{sup TM}) and 21.7% of those receiving iomeprol 350 (Iomeron[reg] (p = 0.02). A total of 23 (3.7%) patients in the iopamidol group and 39 (6.2%) patients in the iomeprol group reported nausea, p = 0.01. Conclusions: The incidence of early adverse

  20. Chemical composition and cardiovascular effects induced by the essential oil of Cymbopogon citratus DC. Stapf, Poaceae, in rats Composição química e efeitos cardiovasculares do óleo essencial de Cymbopogon citratus DC. Stapf, Poaceae, em ratos

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    Flávia V. Moreira


    Full Text Available Cymbopogon citratus DC. Stapf, Poaceae, is used in the folk medicine for hypertension treatment. This work investigated the chemical composition and cardiovascular effects in rats of C. citratus essential oil (EOCC. A phytochemical screening demonstrated the presence of eight constituents, being geranial the major compound (43.08%. In rats, EOCC (1, 5, 10, and 20 mg/kg, i.v. induced transient hypotension and bradycardia that were attenuated by atropine and sodium thiopental, but not by L-NAME or indomethacin. In rings of rat superior mesenteric artery pre-contracted with phenylephrine, EOCC (1 to 3000 µg/mL induced relaxation that was not affected after removal of the endothelium, after TEA or in rings pre-contracted with KCl (80 mM. Furthermore, EOCC (1000 µg/mL was not able to induce additional effect on maximal relaxation of nifedipine (10 µM. In conclusions, EOCC induces hypotension, possibly by reduction in vascular resistance caused by inhibition of the Ca2+ influx, and bradycardia probably due to an activation of cardiac muscarinic receptors.C. citratus é utilizada na medicina popular para tratar hipertensão. Este trabalho investigou a composição química e os efeitos cardiovasculares do óleo essencial do C. citratus (OECC. Foram identificados oito constituintes no OECC, sendo geranial o majoritário (43,08%. Em ratos, o OECC (1, 5, 10 e 20 mg/kg, i.v. induziu hipotensão e bradicardia que foram atenuadas pela atropina e tiopental sódico, mas não por L-NAME ou indometacina. Em anéis de artéria mesentérica de ratos pré-contraídos com fenilefrina, o OECC (1 a 3000 µg/mL induziu relaxamento que não foi afetado após remoção do endotélio, após TEA ou em anéis pré-contraídos com KCl (80 mM. Além disso, o OECC (1000 µg/mL não induziu efeito adicional sobre o relaxamento máximo da nifedipina (10 µM. Em conclusão, o OECC induz hipotensão possivelmente devido à redução da resistência vascular que pode ser causada

  1. Caffeine acts via A1 adenosine receptors to disrupt embryonic cardiac function.

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    Daniela L Buscariollo

    Full Text Available BACKGROUND: Evidence suggests that adenosine acts via cardiac A1 adenosine receptors (A1ARs to protect embryos against hypoxia. During embryogenesis, A1ARs are the dominant regulator of heart rate, and A1AR activation reduces heart rate. Adenosine action is inhibited by caffeine, which is widely consumed during pregnancy. In this study, we tested the hypothesis that caffeine influences developing embryos by altering cardiac function. METHODOLOGY/PRINCIPAL FINDINGS: Effects of caffeine and adenosine receptor-selective antagonists on heart rate were studied in vitro using whole murine embryos at E9.5 and isolated hearts at E12.5. Embryos were examined in room air (21% O(2 or hypoxic (2% O(2 conditions. Hypoxia decreased heart rates of E9.5 embryos by 15.8% and in E12.5 isolated hearts by 27.1%. In room air, caffeine (200 µM had no effect on E9.5 heart rates; however, caffeine increased heart rates at E12.5 by 37.7%. Caffeine abolished hypoxia-mediated bradycardia at E9.5 and blunted hypoxia-mediated bradycardia at E12.5. Real-time PCR analysis of RNA from isolated E9.5 and E12.5 hearts showed that A1AR and A2aAR genes were expressed at both ages. Treatment with adenosine receptor-selective antagonists revealed that SCH-58261 (A2aAR-specific antagonist had no affects on heart function, whereas DPCPX (A1AR-specific antagonist had effects similar to caffeine treatment at E9.5 and E12.5. At E12.5, embryonic hearts lacking A1AR expression (A1AR-/- had elevated heart rates compared to A1AR+/- littermates, A1AR-/- heart rates failed to decrease to levels comparable to those of controls. Caffeine did not significantly affect heart rates of A1AR-/- embryos. CONCLUSIONS/SIGNIFICANCE: These data show that caffeine alters embryonic cardiac function and disrupts the normal cardiac response to hypoxia through blockade of A1AR action. Our results raise concern for caffeine exposure during embryogenesis, particularly in pregnancies with increased risk of

  2. Analysis of electrocardiogram during physical examination among 538 young women%538例青年女性健康体检心电图分析

    Institute of Scientific and Technical Information of China (English)

    郑春娜; 黄丽红


    [ Objective] To understand the abnormal condition of electrocardiogram (ECG) for young women aged from 22 to 31.. [Methods] Using NIHON KOHDEN 9320K12 - lead ECG machine recording synchronously, according to the "Electrocardiography" written by Guo Jihong in the 2002 as the standard of analysis. [ Results] 74 cases (13.8%) were abnormal ECG. Among them, 23 cases (31. 1%) had sinus bradycardia, 19 cases (25.7%) had sinus arrhythmia, 15 cases (20. 3% ) had sinus tachycardia, 13 cases (17. 6% ) had ST -T change, 5 cases (6. 8% ) had premature ventricular complex, and 2 cases (2.7% ) had premature atrial complex. [Conclusion] Sinus bradycardia, sinus arrhythmia, sinus tachycardia, ST - T change and premature complex are common abnormalities for young women.%[目的]了解22~31岁年龄段青年女性的心电图异常发生情况.[方法]采用日本光电9320K12导联心电图机同步描记,以郭继鸿主编的2002年版的《心电图学》为标准,分析538例青年女性健康体检的心电图结果.[结果]心电图异常者74例(13.8%).其中,窦性心动过缓23例(31.1%),窦性心律不齐19例(25.7%),窦性心动过速15例(20.3%).ST -T改变13例(17.6%).室性期前收缩5例(6.8%),房性期前收缩2例(2.7%).[结论]青年女性异常心电图以窦性心动过缓、窦性心律不齐、窦性心动过速、ST -T改变及期前收缩为常见.

  3. 右美托咪啶与咪达唑仑复合舒芬太尼用于肝癌微波治疗术患者麻醉效果的比较%Comparison of anesthetic efficacy of dexmedetomidine and midazolam combined with sufentanil in patients undergoing microwave coagulation therapy for liver cancer

    Institute of Scientific and Technical Information of China (English)

    吴晓丹; 陈彦青; 邹聪华


    Objective To compare the anesthetic efficacy of dexmedetomidine and midazolam combined with sufentanil in patients undergoing microwave coagulation therapy for liver cancer.Methods Forty ASA Ⅱ male patients (aged 35-62 years and weighing 45-70 kg) scheduled for percutaneous microwave coagulation therapy were randomly divided into two groups (n =20 each):midazolam group (group Ⅰ) and dexmedetomidine group (group Ⅱ).A loading dose of midazolam 40 μg/kg (in normal saline 20 ml) was given intravenously over 10 minutes,followed by midazolam infusion at 40 μg·kg-1 · h-1 in group Ⅰ.And a loading dose of dexmedetomidine 1 μg/kg (in normal saline 20 ml) was given intravenously over 10 minutes,followed by dexmedetomidine at 0.5 μg· kg-1 · h-1 in group Ⅱ.At 5 minutes after administration of the loading dose of midazolam or dexmedetomidine,a loading dose of sufentanil 0.2 μg/kg was given,and then patient-controlled intravenous anesthesia (PCIA) with sufentanil (with the background infusion of 0.1 μg·kg-1 · h-1,bolus dose of 0.1 μg/kg and lockout interval of 3 minutes) was used.The operation was started 2 minutes after administration of the loading dose of sufentanil.The incidences of bradycardia,tachycardia,hypotension,hypertension and respiratory depression were recorded.The total attempts and effective pressing times of PCIA were also recorded.Results There was no significant difference in the incidences of bradycardia,tachycardia,hypotension,and hypertension between the two groups (P > 0.05).The incidence of respiratory depression was significantly lower,and the total attempts and effective pressing times were smaller in group Ⅱ than in group Ⅰ (P < 0.05).Conclusion The anesthetic efficacy of dexmedetomidine and sufentanil is better than that of midazolam and sufentanil in patients undergoing microwave coagulation therapy for liver cancer.

  4. Diagnosis value of dynamic state electrocardiogram in sick sinus syndrome%动态心电图在病态窦房结综合征诊断中的应用价值

    Institute of Scientific and Technical Information of China (English)



    目的:探讨动态心电图在病态窦房结综合征诊断中的应用价值。方法选取60例病态窦房结综合征患者作为观察组,并选取60例健康组作为对照组,进行24 h 动态心电图检查,比较两组的检查结果。结果观察组24 h 总心搏数、最高心率、最低心率、24 h 平均心率均低于对照组,差异有统计学意义(p <0•05);观察组发生窦性心动过缓、窦性停搏、慢快综合征等心律失常的患者高于对照组,差异有统计学意义( p <0•01)。结论动态心电图具有简单、无创伤、重复性强的特点,可作为病态窦房结综合征检查的首选方法。%Objective To study the vale of Holter monitoring in sick sinus syndrome. Methods Sixty SSS patients and an_other 60 healthy cases were enrolled in 24_hour AECG examination as experimental group and control group respectively. The difference of examination results was compared between the two groups. Results The total heart beats and average heart rate during 24 hours and maximum and minimum heart rate of experimental group were lower than those of control group,with statisti_call significant differences(p < 0. 05). The incidence of arrhythmias such as sinus bradycardia,sinus arrest and bradycardia_tachycardia syndrome were significantly higher than of control group,also with statistical significant differences(p < 0. 01).Conclusion The detect of dynamic electrocardiogram is simple and without trauma and repeatability,so it can regard as the pre_fer way in diagnosis for sick sinus syndrome.

  5. The application value of 12-lead dynamic electrocardiogram in diagnosis of sick sinus syndrome%12导动态心电图在病窦综合征诊断中的应用价值

    Institute of Scientific and Technical Information of China (English)

    程美莲; 严卫国


    目的:探讨12导动态心电图在病窦综合征诊断中的临床意义。方法选取经临床确诊的40例病窦综合征患者作为观察组,另选取同期40例健康者作为对照组,比较两组人群的动态心电图结果。结果观察组最快心率,最慢心率、24 h平均心率和24 h总心率均低于对照组,差异有统计学意义(P<0.05);观察组窦性心动过缓、窦性停搏、窦房阻滞、交界性逸搏心律及慢快综合征等心律失常检出率均高于对照组,差异有统计学意义(P<0.05)。结论12导动态心电图可全面观察患者心律和心率变化,显著提高心律失常检出率,是早期诊断病窦综合征一项必不可少的检测方法。%Objective To investigate the clinical significance of 12-lead dynamic electrocardiogram in the diagnosis of sick sinus syndrome( SSS) . Methods Forty cases with SSS were selected as the observation group and 40 healthy people as the control group. The 24 hour dynamic electrocardiogram data were compared, including 24 hour total heart rate, average heart rate, maximum heart rate, lowest heart rate and the detection rate of arrhythmia. Results 24 hour total heart rate, average heart rate, maximum heart rate, lowest heart rate of the observation group were lower than those of the control group, and the difference was statistically significant(P<0. 05). The detection rate of arrhythmia, such as sinus bradycardia, sinus arrest, sinoatrial block, junctional escape rhythm, bradycardia-tachycardia syndrome etc. in observation group was obviously higher than that of control group, and the difference was statistically significant(P<0. 05). Conclusion 12-lead dynamic electrocardiogram can fully observe the change of rhythm and heart rate of patients and significantly improve the detectable rate of arrhythmia. 12-lead dynamic electrocardiogram is an indispensable testing method for early diagnosis of SSS.

  6. Dexmedetomidine prolongs the effect of bupivacaine in supraclavicular brachial plexus block

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    Sandhya Agarwal


    Full Text Available Background: We compared the effects of adding dexmedetomidine to a 30 ml solution of 0.325% bupivacaine in supraclavicular brachial plexus block. Onset and duration of sensory and motor block along with the duration of analgesia were the primary endpoints. Materials and Methods: Fifty patients posted for upper limb surgeries were enrolled for a prospective, randomized, double-blind, placebo-controlled trial. Patients were divided into two groups, the control group S and the study group SD. In group S (n = 25, 30 ml of 0.325% bupivacaine + 1 ml normal saline; and in group SD (n = 25, 30 ml of 0.325% bupivacaine + 1 ml (100 μg dexmedetomidine were given for supraclavicular brachial plexus block using the peripheral nerve stimulator. Onset and duration of sensory and motor blocks were assessed along with the duration of analgesia, sedation, and adverse effects, if any. Hemodynamic parameters, like heart rate (HR, systolic arterial blood pressure (SBP, and diastolic arterial blood pressure (DBP were also monitored. Results: Demographic data and surgical characteristics were comparable in both the groups. The onset times for sensory and motor blocks were significantly shorter in SD than S group (P < 0.001, while the duration of blocks was significantly longer (P < 0.001 in SD group. Except for the initial recordings (at 0, 5, 10, and 15 min, heart rate levels in group SD were significantly lower (P < 0.001. SBP and DBP levels in SD group at 15, 30, 45, 60, 90 and 120 min were significantly lower than in S group (P < 0.001. In fact, when the percentage changes in HR/SBP/DBP were compared from 0-5/0-10/0-15/0-30/0-45/0-60/0-90/0-120 min in SD with S group, they came out to be highly significant (P < 0.001 in group SD. The duration of analgesia (DOA was significantly longer in SD group than S group (P < 0.001. Except that, bradycardia was observed in one patient in the group SD, no other adverse effects were observed in either of the groups. Conclusion

  7. Effects of intravenous dexmedetomidine on hyperbaric bupivacaine spinal anesthesia: A randomized study

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    Chilkunda N Dinesh


    Full Text Available Background and Objectives: The present study was designed to evaluate the effect of intravenous dexmedetomidine on spinal anesthesia with 0.5% of hyperbaric bupivacaine. Materials and Methods: One hundred American Society of Anesthesiologists (ASA physical status I/II patients undergoing elective surgeries under spinal anesthesia were randomized into two groups of 50 each. Immediately after subarachnoid block with 3 ml of 0.5% hyperbaric bupivacaine, patients in group D received a loading dose of 1 μg/kg of dexmedetomidine intravenously by infusion pump over 10 min followed by a maintenance dose of 0.5 μg/kg/h till the end of surgery, whereas patients in group C received an equivalent quantity of normal saline. Results: The time taken for regression of motor blockade to modified Bromage scale 0 was significantly prolonged in group D (220.7 ± 16.5 min compared to group C (131 ± 10.5 min (P < 0.001. The level of sensory block was higher in group D (T 6.88 ± 1.1 than group C (T 7.66 ± 0.8 (P < 0.001. The duration for two-dermatomal regression of sensory blockade (137.4 ± 10.9 min vs. 102.8 ± 14.8 min and the duration of sensory block (269.8 ± 20.7 min vs. 169.2 ± 12.1 min were significantly prolonged in group D compared to group C (P < 0.001. Intraoperative Ramsay sedation scores were higher in group D (4.4 ± 0.7 compared to group C (2 ± 0.1 (P < 0.001. Higher proportion of patients in group D had bradycardia (33% vs. 4% (P < 0.001, as compared to group C. The 24-h mean analgesic requirement was less and the time to first request for postoperative analgesic was prolonged in group D than in group C (P < 0.001. Conclusion: Intravenous dexmedetomidine significantly prolongs the duration of sensory and motor block of bupivacaine spinal anesthesia. The incidence of bradycardia is significantly higher when intravenous dexmedetomidine is used as an adjuvant to bupivacaine spinal anesthesia. Dexmedetomidine provides excellent intraoperative

  8. The cardiopulmonary reflexes of spontaneously hypertensive rats are normalized after regression of left ventricular hypertrophy and hypertension

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    T.A. Uggere


    Full Text Available Cardiopulmonary reflexes are activated via changes in cardiac filling pressure (volume-sensitive reflex and chemical stimulation (chemosensitive reflex. The sensitivity of the cardiopulmonary reflexes to these stimuli is impaired in the spontaneously hypertensive rat (SHR and other models of hypertension and is thought to be associated with cardiac hypertrophy. The present study investigated whether the sensitivity of the cardiopulmonary reflexes in SHR is restored when cardiac hypertrophy and hypertension are reduced by enalapril treatment. Untreated SHR and WKY rats were fed a normal diet. Another groups of rats were treated with enalapril (10 mg kg-1 day-1, mixed in the diet; SHRE or WKYE for one month. After treatment, the volume-sensitive reflex was evaluated in each group by determining the decrease in magnitude of the efferent renal sympathetic nerve activity (RSNA produced by acute isotonic saline volume expansion. Chemoreflex sensitivity was evaluated by examining the bradycardia response elicited by phenyldiguanide administration. Cardiac hypertrophy was determined from the left ventricular/body weight (LV/BW ratio. Volume expansion produced an attenuated renal sympathoinhibitory response in SHR as compared to WKY rats. As compared to the levels observed in normotensive WKY rats, however, enalapril treatment restored the volume expansion-induced decrease in RSNA in SHRE. SHR with established hypertension had a higher LV/BW ratio (45% as compared to normotensive WKY rats. With enalapril treatment, the LV/BW ratio was reduced to 19% in SHRE. Finally, the reflex-induced bradycardia response produced by phenyldiguanide was significantly attenuated in SHR compared to WKY rats. Unlike the effects on the volume reflex, the sensitivity of the cardiac chemosensitive reflex to phenyldiguanide was not restored by enalapril treatment in SHRE. Taken together, these results indicate that the impairment of the volume-sensitive, but not the

  9. Ivabradine: A Unique and Intriguing Medication for Treating Cardiovascular Disease. (United States)

    Nawarskas, James J; Bowman, Brandi N; Anderson, Joe R


    There has been much research linking elevated resting heart rate to cardiovascular morbidity and mortality. Based on these findings, a lower resting heart rate would be of theoretical benefit in patients with cardiovascular disease. From a pathophysiologic perspective, a lower resting heart rate would be of particular benefit in patients with ischemic heart disease and/or heart failure. Although β-blockers and nondihydropyridine calcium channel blockers are effective at lowering heart rate, they have many other pharmacologic effects that may not be desirable in some patients, such as negative inotropy. Ivabradine is a drug designed to lower heart rate without any other demonstrable pharmacologic effects; in other words, a pure heart rate-lowering drug. It functions by blocking the hyperpolarization-activated cyclic nucleotide gated channels (f-channels) specific for the sinoatrial node and disrupting If ion current flow. This effectively prolongs diastolic depolarization and slows firing in the sinoatrial node, which lowers heart rate. The effects of ivabradine are most pronounced at higher heart rates (use-dependence), which is important in minimizing the development of symptomatic bradycardia. Clinical trials have demonstrated ivabradine to be an effective antianginal drug both alone and in combination with β-blocker therapy, although it has not been shown to produce a demonstrable effect on reducing major adverse cardiovascular events. In patients with heart failure, ivabradine has demonstrated many hemodynamic benefits, but its effect on clinical outcomes have been mixed and dependent on baseline heart rate, ie, the drug may be of benefit with higher baseline heart rates, but detrimental with low baseline heart rates. The adverse effects of ivabradine are not uncommon, but are rarely severe and include visual disturbances, bradycardia, and atrial fibrillation. Although ivabradine is a very interesting new agent, its variable benefits in large-scale clinical

  10. [Efficacy and safety analysis of ivabradine hydrochloride treatment of Chinese patients with chronic heart failure: subgroup analysis of Chinese patients in the SHIFT study]. (United States)

    Hu, D Y; Huang, D J; Yuan, Z Y; Zhao, R P; Yan, X W; Wang, M H


    Objective: To evaluate the efficacy and safety of ivabradine for the treatment of Chinese patients with chronic heart failure based on the Chinese subgroup data of the systolic heart failure treatment with the I(f) inhibitor ivabradine trial (SHIFT). Method: A total of 6 558 stable outpatients who presented symptoms of heart failure, with a left ventricular ejection fraction (LVEF) ≤35%, sinus rhythms with a heart rate ≥70 bpm participated in the randomized, double-blind, placebo-controlled, international multicenter clinical study.The subset of Chinese patients with heart rate ≥75 bpm was enrolled in the post-hoc subgroup analyses.Patients were randomly allocated by computer-generated assignment through a telephone interactive voice response system to ivabradine group (starting dose 5 mg bid, which was then uptitrated to the maximum 7.5 mg bid) or matched placebo group.The clinical baseline characteristics of participants were obtained and analyzed.The primary outcome endpoint was a composite endpoint of cardiovascular death or hospitalization resulting from worsening HF.The primary safety endpoint included total incidence of adverse events during the study, bradycardia, and adverse visual reaction (phosphenes). Results: A total of 49 Chinese centers enrolled a total of 225 patients with chronic heart failure, of whom, 106 patients were randomized to the ivabradine group and the other 119 patients to the placebo group, and the mean follow-up time was (15.6±5.1) months.By the end of the study, mean heart rate (71.0 bpm vs. 80.3 bpm, Pivabradine group than in the placebo group.The total number of adverse events (129 events, 49.6% PY) in the ivabradine group was lower than that in the placebo group (203 events, 50.8% PY). In the ivabradine group and the placebo group, there were respectively 2 patients (1.9%) and 0 patients experienced bradycardia, 3 patients (2.9%) and 1 patient (0.8%) experienced adverse visual reaction (phosphenes). Conclusions: Ivabradine

  11. Regional haemodynamic effects of carbachol injected into the hypothalamic paraventricular nuclei of conscious, unrestrained rats. (United States)

    Bachelard, H; Gardiner, S M; Kemp, P A; Bennett, T


    Carbachol was injected into the hypothalamic paraventricular nuclei (PVN) of conscious, unrestrained Long Evans rats, chronically instrumented with intravascular catheters and pulsed Doppler probes to assess changes in regional haemodynamics. Bilateral microinjections of carbachol (1 ng-1 microgram) produced increases in blood pressure, bradycardias and vasoconstrictions in renal, superior mesenteric and hindquarters vascular beds. In the presence of phentolamine, the bradycardic and hindquarters vasoconstrictor responses to carbachol were unchanged while the pressor response was smaller due to a reduction in the renal and the superior mesenteric vasoconstriction. In the presence of propranolol, the bradycardic response was reduced, but the pressor and renal vasoconstrictor responses were potentiated, whereas the superior mesenteric and hindquarter vasoconstrictions were not changed significantly. In the presence of phentolamine and propranolol, the heart rate and pressor responses, as well as the renal vasoconstriction, were unchanged, whereas the superior mesenteric vasoconstriction was reduced and the hindquarters vasoconstriction was potentiated. Together these results are consistent with an involvement of the sympathoadrenal system in the pressor response to carbachol injected into the PVN of untreated animals. They indicate that alpha-adrenoceptor-mediated vasoconstriction in the superior mesenteric vascular bed is a particularly important component in that regard. In the presence of the vasopressin antagonist, d(CH2)5(Tyr(Et))DAVP, alone or in combination with phentolamine and propranolol, the pressor response to carbachol was substantially reduced, while the renal and superior mesenteric vasoconstrictor effects were completely abolished; the bradycardia was not significantly affected by this treatment. These results indicate an important involvement of vasopressin in the cardiovascular responses to carbachol injected into the PVN of untreated animals

  12. Severe acute poisoning with homemade Aconitum napellus capsules: toxicokinetic and clinical data. (United States)

    Moritz, Fabienne; Compagnon, Patricia; Kaliszczak, Isabelle Guery; Kaliszczak, Yann; Caliskan, Valérie; Girault, Christophe


    Aconitum napellus is an extremely dangerous plant that contains various toxic diterpenoid alkaloids, mainly aconitine primarily concentrated in the roots. We report a case of acute intoxication of a 21-year-old man admitted to our Emergency Department after the ingestion, in order to sleep, of three homemade Aconitum napellus capsules. Capsules were measured to contain 237 mg of root and 19 microg of aconitine. The patient experienced the first symptoms on wakening 5 hours later with generalized paresthesia, nausea, diarrhea, vertigo, thoracic pain dyspnea, and dyschromatopsia. At admission, 7 hours after intake electrocardiographic analysis showed a sinusal bradycardia with polymorphic and bigeminal ventricular extrasystolia. Cardiovascular and neurological symptoms disappeared, respectively within 11 and 13 hours of ingestion. The patient was discharged from the ICU on day 2. Plasmatic concentrations at H7, H9, H14 H19, and after ingestion were, respectively, of 1.75, 0.75, 0.35, and 0.02 ng/mL. The calculated half-life of aconitine was 3 hours. To our knowledge, this is the first reported case with an aconitine toxicokinetic-effect relationship. The authors stress that clinicians must be aware of possible occurrence of acute poisoning with Aconitum napellus in European countries and in the United States as herbal medicine is becoming increasingly popular.


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    Full Text Available ABSTRACT: BACKGROUND: this randomised control trial is to evaluate unila teral para- vertebral block in elective breast surgery in compa rison with general anaesthesia METHODS: 106 patients of breast surgery were randomised in 2 groups- group-P and group-G. group-P patients received unilateral multiple level paraverteb ral block with 0.25% levo-bupivacaine at T2 to T5 level and group-G patients received general anaesthesia. Pulse, BP were recorded in the perioperative period and rescue analgesic require ment time and VAS scores were recorded in PACU. Recorded data were evaluated after that. RESULTS: In PACU rescue analgesia needed in group-P in 69.22 minutes and in group-G in 41.27 minutes. Post-operative VAS scores were lower in group-P patients at 30 minutes, 1 hr. and 2 hr. There was no incidence of hypotension or hypertension or bradycardia or tachycardia in any group. Patients overall satisfaction score in group-P was 4 vs 3.6 in group-G (p value <0.05 CONCLUSION: Thoracic para-vertebral block is a safe alternative to general anaesthesia for el ective breast surgery as it provides better postoperative analgesia with similar hemodynamic stab ility

  14. Low-power system for the acquisition of the respiratory signal of neonates using diaphragmatic electromyography (United States)

    Torres, Róbinson; López-Isaza, Sergio; Mejía-Mejía, Elisa; Paniagua, Viviana; González, Víctor


    Introduction An apnea episode is defined as the cessation of breathing for ≥15 seconds or as any suspension of breathing accompanied by hypoxia and bradycardia. Obtaining information about the respiratory system in a neonate can be accomplished using electromyography signals from the diaphragm muscle. Objective The purpose of this paper is to illustrate a method by which the respiratory and electrocardiographic signals from neonates can be obtained using diaphragmatic electromyography. Materials and methods The system was developed using single-supply, micropower components, which deliver a low-power consumption system appropriate for the development of portable devices. The stages of the system were tested in both adult and neonate patients. Results The system delivers signals as those expected in both patients and allows the acquisition of respiratory signals directly from the diaphragmatic electromyography. Conclusion This low-power system may present a good alternative for monitoring the cardiac and respiratory activity in newborn babies, both in the hospital and at home. Significance The system delivers good signals but needs to be validated for its use in neonates. It is being used in the Neonatal Intensive Care Unit of the Hospital General de Medellín Luz Castro de Gutiérrez. PMID:28260954

  15. Cardiovascular action of a new carbenoxolone derivative. (United States)

    Filczewski, M; Kosmala, M; Oledzka, K


    The circulatory effects of oleanoic acid sodium hydrogen succinate (OSS), an analogue of the anti-ulcer drug, carbenoxolone, were investigated. As carbenoxolone produces such adverse effects as sodium retention and a subsequent elevation of the arterial blood pressure in man, the present study was aimed at determining whether OSS is similar or different from it in this respect. Carbenoxolone, (43,3 mg/kg po) and OSS (66,6 mg/kg po) were given to rats twice daily for 4 weeks. The systolic blood pressure was elevated already after the first week of treatment. The hypertension was accompanied by bradycardia, which increased with the time of treatment. In the blood an increase in the creatinine level, a decrease in the urea level, and a slight elevation in sodium concentration were found after the treatment, while the potassium concentration during the whole treatment period (4 weeks) remained unchanged. Although the principal aldosterone-like effects of carbenoxolone were attributed to the oxygen presence in position 11 of the glycyrrhetinic acid ring, [8], the absence of an oxygen at that position in OSS did not cause the loss of the adverse circulatory effect.

  16. Intravenous but not perineural clonidine prolongs postoperative analgesia after psoas compartment block with 0.5% levobupivacaine for hip fracture surgery.

    LENUS (Irish Health Repository)

    Mannion, Stephen


    We evaluated the systemic and local effects of clonidine as an analgesic adjunct to psoas compartment block (PCB) with levobupivacaine. In a randomized, prospective, double-blind trial, 36 patients requiring hip fracture surgery received PCB and general anesthesia. Patients were randomized into three groups. Each patient received PCB with 0.4 mL\\/kg of levobupivacaine 0.5%. The control group (group L) received IV saline, the systemic clonidine group (group IC) received IV clonidine 1 mug\\/kg, and the peripheral clonidine group (group C) received IV saline and PCB with clonidine 1 microg\\/kg. The interval from time of completion of block injection to first supplementary analgesic administration was longer in group IC compared with group L (mean +\\/- sd, 13.4 +\\/- 6.1 versus 7.3 +\\/- 3.6 h; P = 0.03). There was no difference between group C and group L (10.3 +\\/- 5.9 versus 7.3 +\\/- 3.6 h; P > 0.05). The groups were similar in terms of 24 h cumulative morphine and acetaminophen consumption. There were no significant differences among groups regarding postoperative adverse effects (bradycardia, hypotension, sedation, and nausea). We conclude that IV but not perineural clonidine (1 microg\\/kg) prolongs analgesia after PCB without increasing the incidence of adverse effects.

  17. Travel-related leptospirosis in Japan: a report on a series of five imported cases diagnosed at the National Center for Global Health and Medicine. (United States)

    Kutsuna, Satoshi; Kato, Yasuyuki; Koizumi, Nobuo; Yamamoto, Kei; Fujiya, Yoshihiro; Mawatari, Momoko; Takeshita, Nozomi; Hayakawa, Kayoko; Kanagawa, Shuzo; Ohmagari, Norio


    Leptospirosis is one of the most common travel-related infections. We report 5 cases of travel-related leptospirosis who presented at our clinic between January 2008 and December 2013. Patients were included in the study if they presented with a clinical profile that was compatible with the disease within 21 days of their return from traveling, which were laboratory-diagnosed as leptospirosis by blood culture, rise in antibody titers in paired sera using the microscopic agglutination test (MAT), and/or DNA detection using flaB-nested PCR. Five leptospirosis cases were evaluated, all of which contracted the disease after exposure to fresh water in Southeast Asian countries. All of the cases had fevers, headaches, conjunctival injections, and relative bradycardia. The pertinent laboratory findings included elevated C-reactive protein levels, elevated creatinine levels, and sterile pyuria. All 5 cases had serum MAT titers that increased by ≥ 4 times in the interval between specimens taken during the acute phase and those taken during the convalescence phase, and leptospiral DNA was detected in plasma and/or urine specimens in 4 cases. Leptospira interrogans was isolated from one patient's blood sample. Patients were treated with penicillin G, minocycline, or doxycycline. One case was cured without antibiotics. A diagnosis of leptospirosis should be considered for febrile travelers who return from Southeast Asian countries to Japan after being exposed to freshwater while traveling.

  18. Case of a sigmoid colon cancer with metachronous metastases to the mesorectum and the abdominal wall

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    Hadjimarcou Andreas


    Full Text Available Abstract Backround Sigmoid colon cancer metachronous metastases commonly occur in the liver and lungs with sporadic reports also to the spleen, stomach, thyroid gland, abdominal wall and upper urinary tract. This is a rare case of metachronous metastases invading the mesorectum and the abdominal wall. Case presentation A 72-year-old female underwent sigmoidectomy for stage I (T2N0 M0 sigmoid colon cancer in May 2008. In June 2009, an abdominal computed tomography scan revealed a tumor 2 cm in size at the lower anterior mesorectum and a second mass 2 cm in size at the anterior abdominal wall midline. Total colonoscopy showed no mucosal lesion. The serum carcinoembryonic antigen level was normal. A biopsy of the mesorectum tumor showed similar histologic characteristics with the primary tumor. Since no other site of recurrence was identified, an abdominoperineal resection was attempted. During the operation and after the removal of the incision recurrence, sinus bradycardia and signs of myocardial ischemia were noticed. A loop transverse colostomy was immediately perfomed and the operation was terminated. Postoperative cardiologic examination revealed an acute myocardium infract. Chemo-radiation of the mesorectum tumor and re-evaluation for surgical excision was decided. Conclusion Metachronous metastasis of the mesorectum from sigmoid colon cancer is extremely rare. Although patterns of lymphatic spread from rectal cancer to sigmoid colon have recently been demonstrated, there is no evidence of metachronous mesorectum invasion from sigmoid colon cancer. This could be the issue for future trials.

  19. Potential Additive Effects of Ticagrelor, Ivabradine, and Carvedilol on Sinus Node

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    Luigi Di Serafino


    Full Text Available A 51-year-old male patient presented to the emergency room with an anterior ST-elevation myocardial infarction. After a loading dose of both ticagrelor and aspirin, the patient underwent primary-PCI on the left anterior descending coronary artery with stent implantation. After successful revascularization, medical therapy included beta-blockers, statins, and angiotensin II receptor antagonists. Two days later, ivabradine was also administered in order to reduce heart rate at target, but the patient developed a severe symptomatic bradycardia and sinus arrest, even requiring administration of both atropine and adrenaline. Ivabradine and ticagrelor have been then suspended and this latter changed with prasugrel. Any other similar event was not reported during the following days. This clinical case raised concerns about the safety of the combination of beta-blockers and ivabradine in patients treated with ticagrelor, particularly during the acute phase of an acute coronary syndrome. These two latter drugs, in particular, might interact with the same receptor. In fact, ivabradine directly modulates the If-channel which is also modulated by the cyclic adenosine monophosphate levels. These latter have been shown to increase after ticagrelor assumption via inhibition of adenosine uptake by erythrocytes. Further studies are warrant to better clarify the safety of this association.

  20. Validation of a Modified Algometer to Measure Mechanical Nociceptive Thresholds in Awake Dogs

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    Ubedullah Kaka


    Full Text Available This study was conducted to validate the use of a modified algometer device to measure mechanical nociceptive thresholds in six dogs. Dogs were administered morphine intravenously (IV at 1 mg/kg or saline at equivolume in a crossover design with one-week washout period. Mechanical nociceptive thresholds were determined before, after the administration of treatments at 5 minutes, and hourly for 8 hours. Thresholds were recorded at the carpal pad, metacarpal foot pad, tibia, femur, and abdomen. Heart rates, body temperature, and respiration were recorded at similar time points. Thresholds increased significantly (P<0.05 from baseline values for up to 3 hours at tibia and abdomen, 4 hours at metacarpal pad, and 5 hours at the carpal pad and femur. Hypothermia, bradycardia, and change in respiration were observed in all dogs after morphine injection. Saline did not alter any threshold levels during the eight-hour study period, indicating no evidence of tolerance, learned avoidance, or local hyperaesthesia. The device and methods of testing were well tolerated by all the dogs. Results suggest that the modified algometer and method of application are useful to measure nociceptive mechanical thresholds in awake dogs.

  1. Effect of carotid and aortic baroreceptors on cardiopulmonary reflex: the role of autonomic function

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    T.L. Fernandes


    Full Text Available We determined the sympathetic and parasympathetic control of heart rate (HR and the sensitivity of the cardiopulmonary receptors after selective carotid and aortic denervation. We also investigated the participation of the autonomic nervous system in the Bezold-Jarish reflex after selective removal of aortic and carotid baroreceptors. Male Wistar rats (220-270 g were divided into three groups: control (CG, N = 8, aortic denervation (AG, N = 5 and carotid denervation (CAG, N = 9. AG animals presented increased arterial pressure (12% and HR (11% compared with CG, while CAG animals presented a reduction in arterial pressure (16% and unchanged HR compared with CG. The sequential blockade of autonomic effects by atropine and propranolol indicated a reduction in vagal function in CAG (a 50 and 62% reduction in vagal effect and tonus, respectively while AG showed an increase of more than 100% in sympathetic control of HR. The Bezold-Jarish reflex was evaluated using serotonin, which induced increased bradycardia and hypotension in AG and CAG, suggesting that the sensitivity of the cardiopulmonary reflex is augmented after selective denervation. Atropine administration abolished the bradycardic responses induced by serotonin in all groups; however, the hypotensive response was still increased in AG. Although the responses after atropine were lower than the responses before the drug, indicating a reduction in vagal outflow after selective denervation, our data suggest that both denervation procedures are associated with an increase in sympathetic modulation of the vessels, indicating that the sensitivity of the cardiopulmonary receptors was modulated by baroreceptor fibers.

  2. Estudo comparativo da anestesia com propofol ou thionembutal em cães Comparative study of the anesthesia in dogs with propofol or thionembutal

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    Jairo Vaidergorn


    Full Text Available Os autores compararam o uso de propofol e thionembutal observando as freqüências cardíaca e respiratória e a presença das seguintes intercorrências: apnéia, tremor, bradicardia, taquicardia, taquipnéia e parada cardíaca. Foram randomizados 100 cães para serem anestesiados com propofol ou thionembutal, sendo monitorizados os parâmetros de interesse ao estudo. Foi constatado que existe importância significantemente maior em relação a ocorrência de apnéia e tremor em ambos os grupos, sendo menores com o uso de propofol. O propofol mostrou-se uma droga mais segura para a anestesia em cães do que o thionembutal.The authors compared the use of propofol and thionembutal in dogs with respect to the heart and respiratory rate and the presence of the following occurrences: apnea, tremor, bradycardia, tachycardia, tachypnea and cardiac arrest. A hundred dogs, in good general conditions, were selected and randomly chosen to be anaesthetized with propofol or thionembutal and parameters were monitored according to the objective of the study. There is a significant importance regarding dog’s apnea and tremor in both groups which are, comparatively smaller with propofol. Propofol has showed to be a safer drug to anaesthetize dogs than thionembutal.

  3. Apparent affinity of 1,3-dipropyl-8-cyclopentylxanthine for adenosine A1 and A2 receptors in isolated tissues from guinea-pigs. (United States)

    Collis, M. G.; Stoggall, S. M.; Martin, F. M.


    1. The classification of adenosine receptor subtypes (A1 and A2) in intact tissues has been based on the order of agonist potency. In this study the apparent affinity of 1,3-dipropyl-8-cyclopentylxanthine (CPX), an antagonist which has been reported to be A1 selective, and the non-selective antagonist 1,3-dimethyl-8-phenylxanthine (8PT) has been evaluated on isolated tissues from the guinea-pig. 2. The isolated tissues used were atria (bradycardic response, proposed A1 sub-type), aorta and trachea (relaxant response, proposed A2 sub-type). 3. Both the xanthines antagonized responses to adenosine in the three tissues but had little or no effect on responses to carbachol (atria), sodium nitrite (aorta) or isoprenaline (trachea). 4. pA2 values for 8PT were similar on the three tissues (6.3-6.7), however, the pA2 value for CPX on the atria (7.9-8.4) was greater than that on the aorta (6.6) or trachea (6.6). 5. These results support the suggestion that the adenosine receptors which mediate bradycardia in the atrium are of the A1 sub-type and that those which mediate relaxation in the aorta and trachea are of the A2 type. PMID:2790383

  4. Hypoxia/reoxygenation-induced myocardial lesions in newborn piglets are related to interindividual variability and not to oxygen concentration

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    Armando Faa


    Full Text Available OBJECTIVE: Evaluation of myocardial histological changes in an experimental animal model of neonatal hypoxiareoxygenation. METHODS: Normocapnic hypoxia was induced in 40 male Landrace/Large White piglets. Reoxygenation was initiated when the animals developed bradycardia (HR 90 min, and E: nine deceased piglets. RESULTS: Histology revealed changes in all heart specimens. Interstitial edema, a wavy arrangement, hypereosinophilia and coagulative necrosis of cardiomyocytes were observed frequently. No differences in the incidence of changes were observed among groups 1-4, whereas marked differences regarding the frequency and the degree of changes were found among groups A-E. Coagulative necrosis was correlated with increased recovery time: this condition was detected post-asphyxia in 14%, 57%, and 100% of piglets with fast, medium, and slow or very slow recovery rates, respectively. CONCLUSIONS: The significant myocardial histological changes observed suggest that this experimental model might be a reliable model for investigating human neonatal cardiac hypoxia-related injury. No correlation was observed between the severity of histological changes and the fiO2 used during reoxygenation. Severe myocardial changes correlated strictly with recovery time, suggesting an unreported individual susceptibility of myocardiocytes to hypoxia, possibly leading to death after the typical time-sequence of events.

  5. Early outcomes after carotid angioplasty with stenting performed by neurologists

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    Bathala Lokesh


    Full Text Available Aims: To evaluate the results of carotid artery angioplasty and stenting (CAS in treating extracranial carotid artery stenosis performed by neurologists in our center and compare the results with other large published series. Materials and Methods: Data for all patients who underwent CAS from January 2003 through November 2007, was retrieved from the Nanjing Stroke Registry. Perioperative and post-procedural complications within 30 days following stenting were analyzed and compared with that from other series. A total number of 75 patients were enrolled, with a mean age of 65.9 ± 8.8 years, and 64 (85.3% of them were male. Results: Procedural success was achieved in 74 patients (98.7%. Pre-treatment stenosis was 73.8 ± 14.9 and post-treatment residual stenosis was less than 10%. Thirty-four patients (45.3% had bilateral carotid artery disease and seven (9.3% had tandem stenosis. The neurological complication rate was 3.9% (one major and two minor strokes. Bradycardia in four (5.3% and hypotension in 13 (17.3% were observed during procedures. Using the Fischer′s exact t test, the complication rate compared with the large published series did not reveal any statistically significant difference (P > 0.05. Conclusions: We conclude that neurologists, with adequate training, can develop and add this technical skill to the existing cognitive skill of vascular neurology and safely perform stenting.

  6. [Alpha 2-adrenoceptor agonists for the treatment of chronic pain]. (United States)

    Kulka, P J


    The antinociceptive effect of alpha(2)-adrenoceptor agonists is mediated by activation of descending inhibiting noradrenergic systems, which modulates 'wide-dynamic-range' neurones. Furthermore, they inhibit the liberation of substance P and endorphines and activate serotoninergic neurones. Despite this variety of antinociceptive actions, there is still little experience with alpha(2)-adrenoceptor agonists as therapeutic agents for use in chronic pain syndromes. Studies in animals and patients have shown that the transdermal, epidural and intravenous administration of the alpha(2)-adrenoceptor agonist clonidine reduces pain intensity in neuropathic pain syndromes for periods varying from some hours up to 1 month. Patients suffering from lancinating or sharp pain respond best to this therapy. Topically applied clonidine (200-300 microg) relieves hyperalgesia in sympathetically maintained pain. Epidural administration of 300 microg clonidine dissolved in 5 ml NaCl 0.9 % has also been shown to be effective. In patients suffering from cancer pain tolerant to opioids, pain control has proved possible again with combinations of opioids and clonidine. In isolated cases clonidine has been administered epidurally at a dose of 1500 microg/day for almost 5 months without evidence for any histotoxic property of clonidine. Side effects often observed during administration of alpha(2)-adrenoceptor agonists are dry mouth, sedation, hypotension and bradycardia. Therapeutic interventions are usually not required.

  7. Cardiac involvement in diphtheria: Study from a tertiary referral infectious disease hospital

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    Alakes Kumar Kole


    Full Text Available Background: Diphtheria is still a fatal disease even in the era of universal immunization. Diphtheria myocarditis, one of the serious complications of respiratory diphtheria may cause death if not recognized and treated properly. Aims and Objectives: To determine the outcomes of cardiac involvement in respiratory diphtheria. Materials and Methods: One hundred (n = 100 patients with respiratory tract diphtheria were evaluated in respect to cardiac involvement. All patients were closely monitored for a minimum period of 4-6 weeks from the onset of respiratory symptoms. Continuous ECG monitoring including blood biochemistry (SGOT, CPK-MB, and Troponin-T were done in each case. Results : The most common symptoms were throat pain seen in 94 cases, palpitation in 56 cases, bull neck in 40 cases, shortness of breath in 12 cases, fever in 9 cases, and nasal regurgitation in 8 cases. Most common complication observed was myocarditis seen in 70 patients and majority of patients (60 were asymptomatic. The ECG changes were T wave inversion in 54 patients, inappropriate sinus tachycardia in 38 patients, ST segment depression in precordial leads in 8 patients, Mobitz type II block in 6 patients, Mobitz type I block in 4 patients, RBBB in 4 patients, multiple atrial ectopics in 4 patients, and sinus bradycardia in 2 patients. A total number of five patients died. Conclusions: Myocarditis was commonest and serious complication of respiratory diphtheria. Increase in vaccination coverage and improvement of socioeconomic status are all effective preventive measures to reduce the incidence of diphtheria.

  8. Pharmacology of Indole and Indazole Synthetic Cannabinoid Designer Drugs AB-FUBINACA, ADB-FUBINACA, AB-PINACA, ADB-PINACA, 5F-AB-PINACA, 5F-ADB-PINACA, ADBICA, and 5F-ADBICA. (United States)

    Banister, Samuel D; Moir, Michael; Stuart, Jordyn; Kevin, Richard C; Wood, Katie E; Longworth, Mitchell; Wilkinson, Shane M; Beinat, Corinne; Buchanan, Alexandra S; Glass, Michelle; Connor, Mark; McGregor, Iain S; Kassiou, Michael


    Synthetic cannabinoid (SC) designer drugs based on indole and indazole scaffolds and featuring l-valinamide or l-tert-leucinamide side chains are encountered with increasing frequency by forensic researchers and law enforcement agencies and are associated with serious adverse health effects. However, many of these novel SCs are unprecedented in the scientific literature at the time of their discovery, and little is known of their pharmacology. Here, we report the synthesis and pharmacological characterization of AB-FUBINACA, ADB-FUBINACA, AB-PINACA, ADB-PINACA, 5F-AB-PINACA, 5F-ADB-PINACA, ADBICA, 5F-ADBICA, and several analogues. All synthesized SCs acted as high potency agonists of CB1 (EC50 = 0.24-21 nM) and CB2 (EC50 = 0.88-15 nM) receptors in a fluorometric assay of membrane potential, with 5F-ADB-PINACA showing the greatest potency at CB1 receptors. The cannabimimetic activities of AB-FUBINACA and AB-PINACA in vivo were evaluated in rats using biotelemetry. AB-FUBINACA and AB-PINACA dose-dependently induced hypothermia and bradycardia at doses of 0.3-3 mg/kg, and hypothermia was reversed by pretreatment with a CB1 (but not CB2) antagonist, indicating that these SCs are cannabimimetic in vivo, consistent with anecdotal reports of psychoactivity in humans.

  9. Digitalis and the sick sinus syndrome. Clinical and electrophysiologic documentation of severe toxic effect on sinus node function. (United States)

    Margolis, J R; Strauss, H C; Miller, H C; Gilbert, M; Wallace, A G


    Digoxin, in a common clinical dose and at a low serum level, brought out severe manifestations of sinus node dysfunction in a patient who had previously undergone successful mitral valve replacement. This report presents the results of extensive clinical and electrophysiologic studies of this patient before and after a digoxin challenge. In the absence of cardiac glycoside, the only demonstrable abnormalities of sinus node function were mild resting sinus bradycardia and failure to respond to atropine administration. Responses to isoproterenol administration, programmed premature atrial stimulation, and overdrive pacing at several cycle lengths were normal. Following the administration of intravenous digoxin, 1.025 mg/24 hrs, the resting sinus cycle length increased and the response to overdrive pacing became markedly abnormal. The latter was followed by sinus pauses in excess of six seconds, even at relatively slow overdrive pacing rates. The electrophysiologic and clinical implications of these data are discussed. It is suggested that despite previous reports that digitalis preparations are relatively well tolerated by patients with sick sinus syndrome, caution should be used when administering these drugs to this group of patients.

  10. Sick sinus syndrome: a review. (United States)

    Semelka, Michael; Gera, Jerome; Usman, Saif


    Sick sinus syndrome refers to a collection of disorders marked by the heart's inability to perform its pacemaking function. Predominantly affecting older adults, sick sinus syndrome comprises various arrhythmias, including bradyarrhythmias with or without accompanying tachyarrhythmias. At least 50 percent of patients with sick sinus syndrome develop alternating bradycardia and tachycardia, also known as tachy-brady syndrome. Sick sinus syndrome results from intrinsic causes, or may be exacerbated or mimicked by extrinsic factors. Intrinsic causes include degenerative fibrosis, ion channel dysfunction, and remodeling of the sinoatrial node. Extrinsic factors can be pharmacologic, metabolic, or autonomic. Signs and symptoms are often subtle early on and become more obvious as the disease progresses. They are commonly related to end-organ hypoperfusion. Cerebral hypoperfusion is most common, with syncope or near-fainting occurring in about one-half of patients. Diagnosis may be challenging, and is ultimately made by electrocardiographic identification of the arrhythmia in conjunction with the presence of symptoms. If electrocardiography does not yield a diagnosis, inpatient telemetry monitoring, outpatient Holter monitoring, event monitoring, or loop monitoring may be used. Electrophysiologic studies also may be used but are not routinely needed. Treatment of sick sinus syndrome includes removing extrinsic factors, when possible, and pacemaker placement. Pacemakers do not reduce mortality, but they can decrease symptoms and improve quality of life.

  11. Asystole due to trigemino-cardiac reflex: a rare complication of trans-sphenoidal surgery for pituitary adenoma. (United States)

    Seker, Askin; Toktas, Zafer Orkun; Peker, Selcuk; Batirel, Halit Abbas; Necmettin Pamir, M


    The trigemino-cardiac reflex (TCR) is a well-known reflexive response in which bradycardia, hypotension, and gastric hypermotility are induced by stimulation of a peripheral or central portion of the trigeminal nerve. This reflex occurs during craniofacial surgery and other operations on or near the cerebellopontine angle, petrosal sinus, orbit and trigeminal ganglion. TCR is a well-known, although not well documented, phenomenon commonly observed during trans-sphenoidal surgery for resection of pituitary adenomas. We report a case in which asystole occurred during trans-sphenoidal surgery on a pituitary adenoma that was infiltrating the right cavernous sinus. When the anesthesiologist reported asystole, the team stopped manipulation and administered intravenous atropine. Intra-operative MRI showed a small tumour remnant in the right cavernous sinus. The operation was terminated but subsequent radiosurgery was planned for the residual tumor. Although TCR is rare and usually self-limiting, this case led us to change our treatment strategy. Surgeons who perform trans-sphenoidal surgery should be aware of this potential problem. Invasive pituitary adenomas should be removed gently and the risk of triggering TCR should be kept in mind.

  12. The trigemino-cardiac reflex: an update of the current knowledge. (United States)

    Schaller, Bernhard; Cornelius, Jan F; Prabhakar, Hemanshu; Koerbel, Andrei; Gnanalingham, Kanna; Sandu, Nora; Ottaviani, Giulia; Filis, Andreas; Buchfelder, Michael


    The trigemino-cardiac reflex (TCR) is clinically defined as the sudden onset of parasympathetic activity, sympathetic hypotension, apnea, or gastric hypermotility during central or peripheral stimulation of any of the sensory branches of the trigeminal nerve. Clinically, the TCR has been reported to occur during craniofacial surgery, manipulation of the trigeminal nerve/ganglion and during surgery for lesion in the cerebellopontine angle, cavernous sinus, and the pituitary fossa. Apart from the few clinical reports, the physiologic function of this brainstem reflex has not yet been fully explored. The manifestation of the TCR can vary from bradycardia and hypotension to asystole. From the experimental findings, the TCR represents an expression of a central reflex leading to rapid cerebrovascular vasodilatation generated from excitation of oxygen-sensitive neurons in the rostral ventro-lateral medulla oblongata. By this physiologic response, the systemic and cerebral circulations may be adjusted in a way that augments cerebral perfusion. This review summarizes the current state of knowledge about TCR.

  13. A new predisposing factor for trigemino-cardiac reflex during subdural empyema drainage: a case report

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    Arasho Belachew


    Full Text Available Abstract Introduction The trigemino-cardiac reflex is defined as the sudden onset of parasympathetic dysrhythmia, sympathetic hypotension, apnea, or gastric hypermotility during stimulation of any of the sensory branches of the trigeminal nerve. Clinically, trigemino-cardiac reflex has been reported to occur during neurosurgical skull-base surgery. Apart from the few clinical reports, the physiological function of this brainstem reflex has not yet been fully explored. Little is known regarding any predisposing factors related to the intraoperative occurrence of this reflex. Case presentation We report the case of a 70-year-old Caucasian man who demonstrated a clearly expressed form of trigemino-cardiac reflex with severe bradycardia requiring intervention that was recorded during surgical removal of a large subdural empyema. Conclusion To the best of our knowledge, this is the first report of an intracranial infection leading to perioperative trigemino-cardiac reflex. We therefore add a new predisposing factor for trigemino-cardiac reflex to the existing literature. Possible mechanisms are discussed in the light of the relevant literature.

  14. Management of the trigeminocardiac reflex: Facts and own experience

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    Arasho Belachew


    Full Text Available The trigeminocardiac reflex (TCR is defined as the sudden onset of parasympathetic dysrhythmia, sympathetic hypotension, apnea, or gastric hyper-motility during stimulation of any of the sensory branches of the trigeminal nerve. The proposed mechanism for the development of TCR is-the sensory nerve endings of the trigeminal nerve send neuronal signals via the Gasserian ganglion to the sensory nucleus of the trigeminal nerve, forming the afferent pathway of the reflex arc. It has been demonstrated that the TCR may occur with mechanical stimulation of all the branches of the trigeminal nerve anywhere along its course (central or peripheral. The reaction subsides with cessation of the stimulus. But, some patients may develop severe bradycardia, asystole, and arterial hypotension which require intervention. The risk factors already known to increase the incidence of TCR include: Hypercapnia; hypoxemia; light general anesthesia; age (more pronounced in children; the nature of the provoking stimulus (stimulus strength and duration; and drugs: Potent narcotic agents (sufentanil and alfentanil; beta-blockers; and calcium channel blockers. Because of the lack of full understanding of the TCR physiology, the current treatment options for patients with TCR include: (i risk factor identification and modification; (ii prophylactic measures; and (iii administration of vagolytic agents or sympathomimetics.


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    Full Text Available INTRODUCTION: Combining minimal invasive surgical and lesser invasive anesthesia technique reduces morbidity and mortality. The aim of the study is to compare spinal anesthesia with the gold standard general anesthesia for elective laparoscopic cholecystectomy. MATERIALS & METHODS: 60 healthy patients were randomized under spinal anesthesia (n=30 & General Anesthesia (n=30 . Hyperbaric 3ml bupivacaine plus 25mcg fenta nyl was administered for spinal group and conventional general anesthesia for GA group. Intraoperative parameters and post - operative pain and recovery were noted. Under spinal group any intraoperative discomfort were taken care by reassurance , drugs or con verted to GA. Questionnaire forms were provided for patients and surgeons to comment about the operation. RESULTS: None of the patients had significant hemodynamic and respiratory disturbance except for transient hypotension and bradycardia. Operative time was comparable. 6patients under spinal anesthesia had right shoulder pain , 2 patients were converted to GA and 4 patients were managed by injection midazolam and infiltration of lignocaine over the diaphragm. There was significant post - operative pain reli ef in spinal group. All the patients were comfortable and surgeons satisfied. CONCLUSION: Spinal anesthesia is adequate and safe for laparoscopic cholecystectomy in otherwise healthy patients and offers better postoperative pain control than general anesth esia without limiting recovery , but require cooperative patient , skilled surgeon , a gentle surgical technique and an enthusiastic anesthesiologist

  16. Differences of promethazine and terfenadine on ion channels in guinea pig ventricular myocytes

    Institute of Scientific and Technical Information of China (English)

    LI Xue-wen; NIU Shuan-cheng; ZHANG Xuan-ping; L(U) Ji-yuan; BAI Feng; ZHANG Ling; WU Bo-wei


    @@ Promethazine, a first generation antihistamine,has an antiarrhythmic effect on ischemia-reperfusion inducing arrhythmias1 and experimental arrhythmias.2 However, terfenadine as a second generation of antihistamine, has been reported to elicit hypotension, bradycardia, prolongation of the QTc interval and torsades de pointes (TdP) like ventricular arrhythmia.3 This may be due to the blockage on rectifier postassium current (Ik) of terfenadine, resulting in the prolongation of the action potential duration (APD) and dispersion of the repolarization duration, which might provoke a specific form of polymorphic ventricular tachydysrhythmia, i.e. TdP.4 In clinical practice,however, the class Ⅲ antiarrhythmic agents, which target on the Ik and prolong the action potential duration and QTc interval, rarely lead to arrhythmias.Other actions must be considered to underlie the arrhythmogenic tendency of terfenadine besides its inhibition on Ik. Though both promethazine and terfenadine block the H1 receptor, there must be a different pharmacology profile between the two compounds on ion channels of cardiac myocytes.Whole-cell patch clamp technique was used to investigate the effects of these two antagonists of the H1 receptor on the main ion currents in cardiac electrical activities.

  17. Chemical sympathectomy restores baroreceptor-heart rate reflex and heart rate variability in rats with chronic nitric oxide deficiency. (United States)

    Chaswal, M; Das, S; Prasad, J; Katyal, A; Fahim, M


    Nitric oxide (NO) plays a crucial role not only in regulation of blood pressure but also in maintenance of cardiac autonomic tone and its deficiency induced hypertension is accompanied by cardiac autonomic dysfunction. However, underlying mechanisms are not clearly defined. We hypothesized that sympathetic activation mediates hemodynamic and cardiac autonomic changes consequent to deficient NO synthesis. We used chemical sympathectomy by 6-hydroxydopamine to examine the influence of sympathetic innervation on baroreflex sensitivity (BRS) and heart rate variability (HRV) of chronic N(G)-nitro-L-arginine methyl ester (L-NAME) treated adult Wistar rats. BRS was determined from heart rate responses to changes in systolic arterial pressure achieved by intravenous administration of phenylephrine and sodium nitroprusside. Time and frequency domain measures of HRV were calculated from 5-min electrocardiogram recordings. Chronic L-NAME administration (50 mg/kg per day for 7 days orally through gavage) in control rats produced significant elevation of blood pressure, tachycardia, attenuation of BRS for bradycardia and tachycardia reflex and fall in time as well as frequency domain parameters of HRV. Sympathectomy completely abolished the pressor as well as tachycardic effect of chronic L-NAME. In addition, BRS and HRV improved after removal of sympathetic influence in chronic L-NAME treated rats. These results support the concept that an exaggerated sympathetic activity is the principal mechanism of chronic L-NAME hypertension and associated autonomic dysfunction.

  18. Frequency of cardiac arrhythmias in high and low- yielding dairy cows

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    Afshin Jafari Dehkordi


    Full Text Available Electrocardiography (ECG may be used to recognize cardiac disorders. Levels of milk production may change the serum electrolytes which its imbalance has a role in cardiac arrhythmia. Fifty high yielding and fifty low yielding Holstein dairy cows were used in this study. Electrocardiography was recorded by base-apex lead and blood samples were collected from jugular vein for measurement of serum elements such as sodium, potassium, calcium, phosphorous, iron and magnesium. Cardiac dysrhythmias were detected more frequent in low yielding Holstein cows (62.00% compared to high yielding Holstein cows (46.00%. The cardiac dysrhythmias that were observed in low yielding Holstein cows included sinus arrhythmia (34.70%, wandering pacemaker (22.45 %, bradycardia (18.37%, tachycardia (10.20%, atrial premature beat (2.04%, sinoatrial block (2.04%, atrial fibrillation (8.16% and atrial tachycardia (2.04%. The cardiac dysrhythmias were observed in high yielding Holstein cows including, sinus arrhythmia (86.95% and wandering pacemaker (13.05%. Also, notched P wave was observed to be 30% and 14% in high- and low- yielding Holstein cows respectively. The serum calcium concentration of low yielding Holstein cows was significantly lower than that of high yielding Holstein cows. There was not any detectable significant difference in other serum elements between high- and low- yielding Holstein cows. Based on the result of present study, could be concluded that low serum concentration of calcium results to more frequent dysrhythmias in low yielding Holstein cows.

  19. Myxedema Coma: A New Look into an Old Crisis

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    Vivek Mathew


    Full Text Available Myxedema crisis is a severe life threatening form of decompensated hypothyroidism which is associated with a high mortality rate. Infections and discontinuation of thyroid supplements are the major precipitating factors while hypothermia may not play a major role in tropical countries. Low intracellular T3 leads to cardiogenic shock, respiratory depression, hypothermia and coma. Patients are identified on the basis of a low index of suspicion with a careful history and examination focused on features of hypothyroidism and precipitating factors. Arrythmias and coagulation disorders are increasingly being identified in myxedema crisis. Thyroid replacement should be initiated as early as possible with careful attention to hypotension, fluid replacement and steroid replacement in an intensive care facility. Studies have shown that replacement of thyroid hormone through ryles tube with a loading dose and maintenance therapy is as efficacious as intravenous therapy. In many countries T3 is not available and oral therapy with T4 can be used effectively without major significant difference in outcomes. Hypotension, bradycardia at presentation, need for mechanical ventilation, hypothermia unresponsive to treatment, sepsis, intake of sedative drugs, lower GCS and high APACHE II scores and Sequential Organ Failure Assessment (SOFA scores more than 6 are significant predictors of mortality in myxedema crisis. Early intervention in hypothyroid patients developing sepsis and other precipitating factors and ensuring continued intake of thyroid supplements may prevent mortality and morbidity associated with myxedema crisis.

  20. The marvel of percutaneous cardiovascular devices in the elderly. (United States)

    Guidoin, Robert; Douville, Yvan; Clavel, Marie-Annick; Zhang, Ze; Nutley, Mark; Pîbarot, Philippe; Dionne, Guy


    Thanks to minimally invasive procedures, frail and elderly patients can also benefit from innovative technologies. More than 14 million implanted pacemakers deliver impulses to the heart muscle to regulate the heart rate (treating bradycardias and blocks). The first human implantation of defibrillators was performed in early 2000. The defibrillator detects cardiac arrhythmias and corrects them by delivering electric shocks. The ongoing development of minimally invasive technologies has also broadened the scope of treatment for elderly patients with vascular stenosis and aneurysmal disease as well as other complex vascular pathologies. The nonsurgical cardiac valve replacement represents one of the most recent and exciting developments, demonstrating the feasibility of replacing a heart valve by way of placement through an intra-arterial or trans-ventricular sheath. Percutaneous devices are particularly well suited for the elderly as the surgical risks of minimally invasive surgery are considerably less as compared to open surgery, leading to a shorter hospital stay, a faster recovery, and improved quality of life.

  1. Intermittent hypoxia in childhood: the harmful consequences versus potential benefits of therapeutic uses

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    Tatiana V. Serebrovskaya


    Full Text Available Intermittent hypoxia often occurs in early infancy in both preterm and term infants and especially at 36 to 44 weeks postmenstrual age. These episodes of intermittent hypoxia could result from sleep-disordered breathing or may be temporally unrelated to apnea or bradycardia events. There are numerous reports indicating adverse effects of intermittent hypoxia on development, behavior, academic achievement and cognition in children with sleep apnea syndrome. It remains uncertain the exact causative relationship between the neurocognitive and behavioral morbidities and intermittent hypoxia and/or its associated sleep fragmentation. On the other hand, well-controlled and moderate intermittent hypoxia conditioning/training has been used in sick children for treating their various forms of bronchial asthma, allergic dermatoses, autoimmune thyroiditis, cerebral palsy, and obesity. This review article provides an updated and impartial analysis on the currently available evidence in supporting either side of the seemingly contradictory scenarios. We wish to stimulate a comprehensive understanding of such a complex physiological phenomenon as intermittent hypoxia, which may be accompanied by other confounding factors (e.g. hypercapnia, polycythemia, in order to prevent or reduce its harmful consequences, while maximize its potential utility as an effective therapeutic tool in pediatric patients.

  2. Mitochondria and NMDA receptor-dependent toxicity of berberine sensitizes neurons to glutamate and rotenone injury.

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    Kai Kysenius

    Full Text Available The global incidence of metabolic and age-related diseases, including type 2 diabetes and Alzheimer's disease, is on the rise. In addition to traditional pharmacotherapy, drug candidates from complementary and alternative medicine are actively being pursued for further drug development. Berberine, a nutraceutical traditionally used as an antibiotic, has recently been proposed to act as a multi-target protective agent against type 2 diabetes, dyslipidemias, ischemic brain injury and neurodegenerative diseases, such as Parkinson's and Alzheimer's disease. However, the safety profile of berberine remains controversial, as isolated reports suggest risks with acute toxicity, bradycardia and exacerbation of neurodegeneration. We report that low micromolar berberine causes rapid mitochondria-dependent toxicity in primary neurons characterized by mitochondrial swelling, increased oxidative stress, decreased mitochondrial membrane potential and depletion of ATP content. Berberine does not induce caspase-3 activation and the resulting neurotoxicity remains unaffected by pan-caspase inhibitor treatment. Interestingly, inhibition of NMDA receptors by memantine and MK-801 completely blocked berberine-induced neurotoxicity. Additionally, subtoxic nanomolar concentrations of berberine were sufficient to sensitize neurons to glutamate excitotoxicity and rotenone injury. Our study highlights the need for further safety assessment of berberine, especially due to its tendency to accumulate in the CNS and the risk of potential neurotoxicity as a consequence of increasing bioavailability of berberine.

  3. The use of diagnostic imaging for identifying abnormal gas accumulations in cetaceans and pinnipeds.

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    Sophie eDennison


    Full Text Available Recent dogma suggested that marine mammals are not at risk of decompression sickness (DCS due to a number of evolutionary adaptations. Several proposed adaptations exist. Lung compression and alveolar collapse that terminate gas exchange before a depth is reached where supersaturation is significant and bradycardia with peripheral vasoconstriction affecting the distribution, and dynamics of blood and tissue nitrogen levels. Published accounts of gas and fat emboli and dysbaric osteonecrosis in marine mammals and theoretical modeling have challenged this view-point, suggesting that decompression-like symptoms may occur under certain circumstances, contrary to common belief. Diagnostic imaging modalities are invaluable tools for the non-invasive examination of animals for evidence of gas and have been used to demonstrate the presence of incidental decompression-related renal gas accumulations in some stranded cetaceans. Diagnostic imaging has also contributed to the recognition of clinically significant gas accumulations in live and dead cetaceans and pinnipeds. Understanding the appropriate application and limitations of the available imaging modalities is important for accurate interpretation of results. The presence of gas may be incidental and must be interpreted cautiously alongside all other available data including clinical examination, clinical laboratory testing, gas analysis, necropsy examination and histology results.

  4. Catatonia in Older Adult Individuals with Intellectual Disabilities

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    Megan White


    Full Text Available Catatonia has been described in children with intellectual disabilities (IDs. These are the first three published cases of catatonia in adults older than 50 years of age with IDs. They were followed using the KANNER scale and, in one case, creatinine phosphokinase (CPK monitoring. Case 1 is a 67-year-old Caucasian who probably had been having intermittent episodes of undiagnosed catatonia withdrawal for many years. His episodes of agitation and withdrawal behavior responded to lorazepam up to 8 mg/day. Case 2 is a 63-year-old Caucasian male who had probably had undiagnosed catatonic episodes since age 25. An agitation episode that rated 88 on Part 2 of the KANNER scale ended within minutes after he received 1 mg of intramuscular lorazepam. He had no symptom relapses for 4 years after getting stable oral lorazepam doses (3–8.5 mg/day. Case 3 is a 55-year-old African-American male with severe ID and bradycardia (with a pacemaker. He had been “institutionalized” since age 22 and his undiagnosed catatonic episodes appeared to have been intermittently present for at least the last ten years. As he became tolerant and experienced symptom relapse, oral lorazepam was slowly increased (1.5–18 mg/day. Electroconvulsive therapy was ruled out due to his pacemaker.

  5. Clinical cardiovascular experiences with iopamidol: a new non-ionic contrast medium. (United States)

    Partridge, J B; Robinson, P J; Turnbull, C M; Stoker, J B; Boyle, R M; Morrison, G W


    Iopamidol, a new non-ionic water-soluble contrast medium, has been compared with standard ionic media in a number of cardiovascular applications. It is stable in aqueous solution, is much less viscous and only slightly more osmolar than metrizamide. Compared to sodium meglumine diatrizoate in a series of 40 coronary arteriograms, it produced a consistent and highly significant decrease in the incidence and severity of hypotension and bradycardia following intracoronary injection. In the same group and in 62 children undergoing ventricular or great vessel angiocardiography, a subjective assessment of patient reaction showed that iopamidol was better tolerated than the ionic medium. There was a very strong patient preference for iopamidol in a group of 20 of the adult patients who had also consented to femoral artery injections of both media. Throughout these series there was no detectable difference in arterial image quality between the media. Venous phase opacification during arterioportography was assessed in 11 cases comparing iopamidol with sodium meglumine iothalamate. No significant difference was found. We conclude that iopamidol is clearly preferable to ionic media for routine cardiovascular applications.

  6. Clonidine versus tramadol for post spinal shivering during caesarean section: A randomized double blind clinical study

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    Velayudha S Reddy


    Full Text Available Background : Control of post spinal shivering is essential for optimal perioperative care, which can be achieved either by oral or parental medications. The present study is designed to evaluate the efficacy and safety of intravenous low-dose clonidine and tramadol in the treatment of post spinal shivering. Materials and Methods : In this prospective, a double blind, randomized study, 90 ASA grade I or II, parturients aged 18 - 35 years, undergoing caesarean section under spinal anaesthesia, who subsequently developed shivering grade 3 or 4, were randomized into two groups, to receive either clonidine or tramadol. The efficacy and response rate of the study drugs were evaluated and recorded. Side effects like, nausea, vomiting, hypotension, bradycardia, dry mouth, sedation, skin rash and headache, if present, were recorded. All data were analyzed by using the Chi square test and the Z-test. Results : There were significant differences in the response rate between the drugs (P < 0.05. Time taken from the starting of treatment to cessation of shivering was significantly less with the tramadol group (P < 0.05, however, the frequency of nausea, vomiting, sedation and headache were also significantly more in the tramadol group Conclusion : In our study we concluded that both clonidine and tramadol control shivering. However, the response rate was higher and time taken to control shivering was lesser with tramadol, but the response rate and the side effects were lesser with clonidine.

  7. Abnormal arterial flows by a distributed model of the fetal circulation. (United States)

    van den Wijngaard, Jeroen P H M; Westerhof, Berend E; Faber, Dirk J; Ramsay, Margaret M; Westerhof, Nico; van Gemert, Martin J C


    Modeling the propagation of blood pressure and flow along the fetoplacental arterial tree may improve interpretation of abnormal flow velocity waveforms in fetuses. The current models, however, either do not include a wide range of gestational ages or do not account for variation in anatomical, vascular, or rheological parameters. We developed a mathematical model of the pulsating fetoumbilical arterial circulation using Womersley's oscillatory flow theory and viscoelastic arterial wall properties. Arterial flow waves are calculated at different arterial locations from which the pulsatility index (PI) can be determined. We varied blood viscosity, placental and brain resistances, placental compliance, heart rate, stiffness of the arterial wall, and length of the umbilical arteries. The PI increases in the umbilical artery and decreases in the cerebral arteries, as a result of increasing placental resistance or decreasing brain resistance. Both changes in resistance decrease the flow through the placenta. An increased arterial stiffness increases the PIs in the entire fetoplacental circulation. Blood viscosity and peripheral bed compliance have limited influence on the flow profiles. Bradycardia and tachycardia increase and decrease the PI in all arteries, respectively. Umbilical arterial length has limited influence on the PI but affects the mean arterial pressure at the placental cord insertion. The model may improve the interpretation of arterial flow pulsations and thus may advance both the understanding of pathophysiological processes and clinical management.


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    Nayna S Solanki


    Full Text Available Background: Pain management after tonsillectomy in children remains a dilemma for anaesthesiologist. The study was designed to compare the effect of pre-incisional infiltration of Bupivacaine (0.25% versus Diclofenac suppository on postoperative pain relief in children. Methodology: Fifty patients of American Society of Anaesthesiology grade – I, aged between 1 and 15 years undergoing elective tonsillectomy were selected. They were randomly divided equally into group A and B. Five minutes before incision, peritonsillar fossa were infiltrated with 5 ml Bupivacaine(0.25% in group A patients. Group B received Diclofenac suppository 2mg/kg after induction. Intra operatively all patients were observed for vital parameters. Post-operatively all the patients were observed for 24 hours for analgesia using observer pain scale, analgesic requirement, vital data and other complications. Result: Diclofenac suppository is a better option for post-operative analgesia in paediatric patients undergoing tonsillectomy as compared to bupivacaine infiltration as there were significant difference in pain score (P<0.05 after two hours onwards post operatively. Complications like bradycardia, hypotension, allergic reaction and convulsion were not found in either group. Conclusion: Diclofenac suppository is a better option as compared to pre-incisional bupivacaine infiltration because of its convenience and duration of analgesia. [National J of Med Res 2012; 2(1.000: 5-7

  9. [Gamma-hydroxybutyrate (GHB) and its lactone (GBL) as psychoactive substances]. (United States)

    Krajewska, Anna; Kwiecień-Obara, Ewelina; Szponar, Jarosław; Majewska, Magdalena; Kołodziej, Małgorzata


    Gammabutyrolactone is included in the solvent such as wheel cleaners, pesticides, cosmetics, drugs. After ingestion GBL is converted to gamma-hydroxybutyrate. Both substances are classified as so called "club drugs" and their action is characterized by euphoria, sedation, and induction of retrograde amnesia of events. These activities were basis for the use of GHB and its lactone as rape pill. Acute poisoning with these compounds causes confusion, agitation, ataxia, nausea, vomiting, nystagmus, dyskinesia, hallucinations, coma, irregular breathing, hypothermia, bradycardia, hypotension, convulsions, respiratory paralysis and thus respiratory arrest. These substances carry a risk of development of physical addiction of the hard proceeding of abstinence syndrome. In the USA there is a ban on the sale and promotion of these compounds. In Poland despite the fact that GHB is a controlled substance, there is no regulation of GBL trading. The aim of this paper is to summarize current knowledge regarding the pharmacology, impact on the human body, toxicity, and the effects of chronic abuse of these substances.

  10. An unusual case of hypothermia associated with therapeutic doses of olanzapine: a case report

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    Ratnayake Shiroma L


    Full Text Available Abstract Introduction We report a case of a 42-year-old man who had symptomatic hypothermia as a result of taking olanzapine for paranoid schizophrenia. According to published data, only a few cases of hypothermia associated with olanzapine have been reported since its introduction into clinical use. Case presentation A 42-year-old Sri Lankan man with schizophrenia who was being treated with a therapeutic dose of olanzapine presented with reduced level of consciousness. He had a core temperature of 32°C and was bradycardic. At the time of admission, the electrocardiogram showed sinus bradycardia with J waves. He did not have any risk factors for developing hypothermia except the use of olanzapine. There was improvement in his clinical condition with reversal of electrocardiogram changes following gradual rewarming and the omission of olanzapine. Conclusion Hypothermia induced by antipsychotic medications is not uncommon, but olanzapine-induced hypothermia is rare and occurrence has been reported during initiation or increasing the dose. But here the patient developed hypothermia without dose adjustment.

  11. Cardiac-specific VLCAD deficiency induces dilated cardiomyopathy and cold intolerance (United States)

    Xiong, Dingding; He, Huamei; James, Jeanne; Tokunaga, Chonan; Powers, Corey; Huang, Yan; Osinska, Hanna; Towbin, Jeffrey A.; Purevjav, Enkhsaikhan; Balschi, James A.; Javadov, Sabzali; McGowan, Francis X.; Strauss, Arnold W.


    The very long-chain acyl-CoA dehydrogenase (VLCAD) enzyme catalyzes the first step of mitochondrial β-oxidation. Patients with VLCAD deficiency present with hypoketotic hypoglycemia and cardiomyopathy, which can be exacerbated by fasting and/or cold stress. Global VLCAD knockout mice recapitulate these phenotypes: mice develop cardiomyopathy, and cold exposure leads to rapid hypothermia and death. However, the contribution of different tissues to development of these phenotypes has not been studied. We generated cardiac-specific VLCAD-deficient (cVLCAD−/−) mice by Cre-mediated ablation of the VLCAD in cardiomyocytes. By 6 mo of age, cVLCAD−/− mice demonstrated increased end-diastolic and end-systolic left ventricular dimensions and decreased fractional shortening. Surprisingly, selective VLCAD gene ablation in cardiomyocytes was sufficient to evoke severe cold intolerance in mice who rapidly developed severe hypothermia, bradycardia, and markedly depressed cardiac function in response to fasting and cold exposure (+5°C). We conclude that cardiac-specific VLCAD deficiency is sufficient to induce cold intolerance and cardiomyopathy and is associated with reduced ATP production. These results provide strong evidence that fatty acid oxidation in myocardium is essential for maintaining normal cardiac function under these stress conditions. PMID:24285112

  12. Time course of the hemodynamic responses to aortic depressor nerve stimulation in conscious spontaneously hypertensive rats

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    Durand, M.T.; Mota, A.L. [Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Barale, A.R. [Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, MG (Brazil); Castania, J.A.; Fazan, R. Jr.; Salgado, H.C. [Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)


    The time to reach the maximum response of arterial pressure, heart rate and vascular resistance (hindquarter and mesenteric) was measured in conscious male spontaneously hypertensive (SHR) and normotensive control rats (NCR; Wistar; 18-22 weeks) subjected to electrical stimulation of the aortic depressor nerve (ADN). The parameters of stimulation were 1 mA intensity and 2 ms pulse length applied for 5 s, using frequencies of 10, 30, and 90 Hz. The time to reach the hemodynamic responses at different frequencies of ADN stimulation was similar for SHR (N = 15) and NCR (N = 14); hypotension = NCR (4194 ± 336 to 3695 ± 463 ms) vs SHR (3475 ± 354 to 4494 ± 300 ms); bradycardia = NCR (1618 ± 152 to 1358 ± 185 ms) vs SHR (1911 ± 323 to 1852 ± 431 ms), and the fall in hindquarter vascular resistance = NCR (6054 ± 486 to 6550 ± 847 ms) vs SHR (4849 ± 918 to 4926 ± 646 ms); mesenteric = NCR (5574 ± 790 to 5752 ± 539 ms) vs SHR (5638 ± 648 to 6777 ± 624 ms). In addition, ADN stimulation produced baroreflex responses characterized by a faster cardiac effect followed by a vascular effect, which together contributed to the decrease in arterial pressure. Therefore, the results indicate that there is no alteration in the conduction of the electrical impulse after the site of baroreceptor mechanical transduction in the baroreflex pathway (central and/or efferent) in conscious SHR compared to NCR.

  13. The Popeye Domain Containing Genes and cAMP Signaling

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    Thomas Brand


    Full Text Available 3'-5'-cyclic adenosine monophosphate (cAMP is a second messenger, which plays an important role in the heart. It is generated in response to activation of G-protein-coupled receptors (GPCRs. Initially, it was thought that protein kinase A (PKA exclusively mediates cAMP-induced cellular responses such as an increase in cardiac contractility, relaxation, and heart rate. With the identification of the exchange factor directly activated by cAMP (EPAC and hyperpolarizing cyclic nucleotide-gated (HCN channels as cAMP effector proteins it became clear that a protein network is involved in cAMP signaling. The Popeye domain containing (Popdc genes encode yet another family of cAMP-binding proteins, which are prominently expressed in the heart. Loss-of-function mutations in mice are associated with cardiac arrhythmia and impaired skeletal muscle regeneration. Interestingly, the cardiac phenotype, which is present in both, Popdc1 and Popdc2 null mutants, is characterized by a stress-induced sinus bradycardia, suggesting that Popdc proteins participate in cAMP signaling in the sinuatrial node. The identification of the two-pore channel TREK-1 and Caveolin 3 as Popdc-interacting proteins represents a first step into understanding the mechanisms of heart rate modulation triggered by Popdc proteins.


    Institute of Scientific and Technical Information of China (English)

    Qing-bo Fan; Ming-ying Gai; Jian-qiu Yang; Fei-fei Xing


    Objective To explore fetal arrhythmia clinical significance and its correlation with fetal prognosis.Methods Twenty-six cases of fetal arrhythmia detected among 12 799 pregnant women recorded over a ten-year period in Peking Uinon Medical College (PUMC) Hospital were reviewed retrospectively. Fetal arrhythmia was diagnosed by fetal auscultation, ultrasonography, electric fetal heart monitoring, and fetal echocardiography.Results Twenty-six fetuses were documented with fetal arrhythmia (3 tachycardia, 4 bradycardia, 19 normal heart rate with irregular fetal cardiac rhythm). The incidence of fetal arrhythmia in our hospital was 0.2%. They were diagnosed at the average of 35 weeks' gestation (15 to 41 weeks). Twenty-two cases were diagnosed by antenatal fetal auscultation, 1 case was diagnosed by ultrasonography, and 3 cases were diagnosed by electric fetal heart monitoring. Fetal echocardiograms were performed on 17 fetuses, 6 cases (35.3%) of which showed that ventricular premature beats with normal structure of fetal heart.All neonates survived postnatally and 24 of them (92.3%) were followed up. Echocardiograms were performed for 16 neonates and 2 of them were identified as atrial septal defects with normal heart rhythms. The results of follow-up showed that the two patients had no apparent clinical manifestation. The echocardiogram showed that atrial septal defect obliterated already.Conclusion The prognosis is well for most of the fetuses with arrhythmias, with low incidence of heart deformation.

  15. Female alcoholics: electrocardiographic changes and associated metabolic and electrolytic disorders

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    Borini Paulo


    Full Text Available OBJECTIVE: To identify the electrocardiographic changes and their associations with metabolic and electrolytic changes in female alcoholics. METHODS: The study comprised 44 female alcoholics with no apparent physical disorder. They underwent the following examinations: conventional electrocardiography; serologic tests for syphilis, Chagas' disease, and hepatitis B and C viruses; urinary pregnancy testing; hematimetric analysis; biochemical measurements of albumin, fibrinogen, fasting and postprandial glycemias, lipids, hepatic enzymes, and markers for tissue necrosis and inflammation. RESULTS: Some type of electrocardiographic change was identified in 33 (75% patients. In 17 (38.6% patients, more than one of the following changes were present: prolonged QTc interval in 24 (54.5%, change in ventricular repolarization in 11(25%, left ventricular hypertrophy in 6 (13.6%, sinus bradycardia in 4 (9.1%, sinus tachycardia in 3 (6.8%, and conduction disorder in 3 (6.8%. The patients had elevated mean serum levels of creatine phosphokinase, aspartate aminotransferases, and gamma glutamyl transferase, as well as hypocalcemia and low levels of total cholesterol and LDL-cholesterol. The patients with altered electrocardiograms had a more elevated age, a lower alcohol consumption, hypopotassemia, and significantly elevated levels of triglycerides, postprandial glucose, sodium and gamma glutamyl transferase than those with normal electrocardiograms. The opposite occurred with fasting glycemia, magnesium, and alanine aminotransferase. CONCLUSION: The electrocardiographic changes found were prolonged QTc interval, change in ventricular repolarization, and left ventricular hypertrophy. Patients with normal and abnormal electrocardiograms had different metabolic and electrolytic changes.

  16. Control of respiration in fish, amphibians and reptiles

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    E.W. Taylor


    Full Text Available Fish and amphibians utilise a suction/force pump to ventilate gills or lungs, with the respiratory muscles innervated by cranial nerves, while reptiles have a thoracic, aspiratory pump innervated by spinal nerves. However, fish can recruit a hypobranchial pump for active jaw occlusion during hypoxia, using feeding muscles innervated by anterior spinal nerves. This same pump is used to ventilate the air-breathing organ in air-breathing fishes. Some reptiles retain a buccal force pump for use during hypoxia or exercise. All vertebrates have respiratory rhythm generators (RRG located in the brainstem. In cyclostomes and possibly jawed fishes, this may comprise elements of the trigeminal nucleus, though in the latter group RRG neurons have been located in the reticular formation. In air-breathing fishes and amphibians, there may be separate RRG for gill and lung ventilation. There is some evidence for multiple RRG in reptiles. Both amphibians and reptiles show episodic breathing patterns that may be centrally generated, though they do respond to changes in oxygen supply. Fish and larval amphibians have chemoreceptors sensitive to oxygen partial pressure located on the gills. Hypoxia induces increased ventilation and a reflex bradycardia and may trigger aquatic surface respiration or air-breathing, though these latter activities also respond to behavioural cues. Adult amphibians and reptiles have peripheral chemoreceptors located on the carotid arteries and central chemoreceptors sensitive to blood carbon dioxide levels. Lung perfusion may be regulated by cardiac shunting and lung ventilation stimulates lung stretch receptors.

  17. Control of respiration in fish, amphibians and reptiles

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    E.W. Taylor

    Full Text Available Fish and amphibians utilise a suction/force pump to ventilate gills or lungs, with the respiratory muscles innervated by cranial nerves, while reptiles have a thoracic, aspiratory pump innervated by spinal nerves. However, fish can recruit a hypobranchial pump for active jaw occlusion during hypoxia, using feeding muscles innervated by anterior spinal nerves. This same pump is used to ventilate the air-breathing organ in air-breathing fishes. Some reptiles retain a buccal force pump for use during hypoxia or exercise. All vertebrates have respiratory rhythm generators (RRG located in the brainstem. In cyclostomes and possibly jawed fishes, this may comprise elements of the trigeminal nucleus, though in the latter group RRG neurons have been located in the reticular formation. In air-breathing fishes and amphibians, there may be separate RRG for gill and lung ventilation. There is some evidence for multiple RRG in reptiles. Both amphibians and reptiles show episodic breathing patterns that may be centrally generated, though they do respond to changes in oxygen supply. Fish and larval amphibians have chemoreceptors sensitive to oxygen partial pressure located on the gills. Hypoxia induces increased ventilation and a reflex bradycardia and may trigger aquatic surface respiration or air-breathing, though these latter activities also respond to behavioural cues. Adult amphibians and reptiles have peripheral chemoreceptors located on the carotid arteries and central chemoreceptors sensitive to blood carbon dioxide levels. Lung perfusion may be regulated by cardiac shunting and lung ventilation stimulates lung stretch receptors.

  18. Nodular Regenerative Hyperplasia of Liver Mimicking Cirrhosis:a Case Report

    Institute of Scientific and Technical Information of China (English)


    A 34-year-old man with no history of any abdominal pain or fatigue was admitted to our hospital in June 2008 due to the cirrhosis found incidentally during a physical examination. Laboratory examination, electrocardiograph, abdominal ultrasonography and magnetic resonance imaging were carried out during his hospitalization. However, according to the results of the above measures, the diagnosis of nodular regenerative hyperplasia of the liver (NRHL) could not be made. The result of electrocardiograph showed there was no sinus bradycardia. The abdominal ultrasonography showed evidence of hepatosplenomegaly, and magnetic resonance imaging showed multiple non-enhancing hepatic nodules. Histologic conifrmation was available by means of liver biopsy and the deifnitive diagnosis of NRHL was conifrmed histologically by liver biopsy. NRHL always presents with signs of portal hypertension with little evidence of obvious liver disease, NRHL may mimick the cirrhosis of liver and be easily confused with cirrhosis of the liver nodules, so liver biopsy should be recommended for correct diagnosis. The clinical, radiological and pathologic features of this case with NRHL was reported in order to familiarize the physicians with its clinical manifestations.

  19. Hypoxemic and ischemic tolerance in emperor penguins. (United States)

    Zenteno-Savin, T; St Leger, J; Ponganis, P J


    Oxygen store depletion and a diving bradycardia in emperor penguins (Aptenodytes forsteri) expose tissues to critical levels of hypoxemia and ischemia. To assess the prevention of re-perfusion injury and reactive oxygen species (ROS) damage in emperor penguins, superoxide radical production, lipid peroxidation (thiobarbituric acid reactive substances (TBARS)), and antioxidant enzyme activity profiles in biopsy samples from muscle and liver were determined and compared to those in the chicken and 8 species of flighted marine birds (non-divers and plunge divers). In muscle of emperor penguins, superoxide production and TBARS levels were not distinctly different from those in the other species; among the antioxidant enzymes, catalase (CAT) and glutathione-S-transferase (GST) activities were significantly elevated above all species. In the liver of emperor penguins, TBARS levels were not significantly different from other species; only CAT activity was significantly elevated, although GST and glutathione peroxidase (GPX) activities were 2-3 times higher than those in other species. The potential for ROS formation and lipid peroxidation is not reduced in the pectoral muscle or liver of the emperor penguin. Scavenging of hydrogen peroxide by CAT and the conjugation of glutathione with reactive intermediates and peroxides by GST and GPX appear to be important in the prevention of ROS damage and re-perfusion injury in these birds.

  20. Muscle energy stores and stroke rates of emperor penguins: implications for muscle metabolism and dive performance. (United States)

    Williams, Cassondra L; Sato, Katsufumi; Shiomi, Kozue; Ponganis, Paul J


    In diving birds and mammals, bradycardia and peripheral vasoconstriction potentially isolate muscle from the circulation. During complete ischemia, ATP production is dependent on the size of the myoglobin oxygen (O(2)) store and the concentrations of phosphocreatine (PCr) and glycogen (Gly). Therefore, we measured PCr and Gly concentrations in the primary underwater locomotory muscle of emperor penguin and modeled the depletion of muscle O(2) and those energy stores under conditions of complete ischemia and a previously determined muscle metabolic rate. We also analyzed stroke rate to assess muscle workload variation during dives and evaluate potential limitations on the model. Measured PCr and Gly concentrations, 20.8 and 54.6 mmol kg(-1), respectively, were similar to published values for nondiving animals. The model demonstrated that PCr and Gly provide a large anaerobic energy store, even for dives longer than 20 min. Stroke rate varied throughout the dive profile, indicating muscle workload was not constant during dives as was assumed in the model. The stroke rate during the first 30 s of dives increased with increased dive depth. In extremely long dives, lower overall stroke rates were observed. Although O(2) consumption and energy store depletion may vary during dives, the model demonstrated that PCr and Gly, even at concentrations typical of terrestrial birds and mammals, are a significant anaerobic energy store and can play an important role in the emperor penguin's ability to perform long dives.

  1. Sympathetic nerve activity and simulated diving in healthy humans. (United States)

    Shamsuzzaman, Abu; Ackerman, Michael J; Kuniyoshi, Fatima Sert; Accurso, Valentina; Davison, Diane; Amin, Raouf S; Somers, Virend K


    The goal of our study was to develop a simple and practical method for simulating diving in humans using facial cold exposure and apnea stimuli to measure neural and circulatory responses during the stimulated diving reflex. We hypothesized that responses to simultaneous facial cold exposure and apnea (simulated diving) would be synergistic, exceeding the sum of responses to individual stimuli. We studied 56 volunteers (24 female and 32 male), average age of 39 years. All subjects were healthy, free of cardiovascular and other diseases, and on no medications. Although muscle sympathetic nerve activity (MSNA), blood pressure, and vascular resistance increased markedly during both early and late phases of simulated diving, significant reductions in heart rate were observed only during the late phase. Total MSNA during simulated diving was greater than combined MSNA responses to the individual stimuli. We found that simulated diving is a powerful stimulus to sympathetic nerve traffic with significant bradycardia evident in the late phase of diving and eliciting synergistic sympathetic and parasympathetic responses. Our data provide insight into autonomic triggers that could help explain catastrophic cardiovascular events that may occur during asphyxia or swimming, such as in patients with obstructive sleep apnea or congenital long QT syndrome.

  2. [Signs of extreme vagotonia in the electrocardiogram of an Olympic 5km running champion]. (United States)

    Chrástek, J


    Hypokinesia (lack of exercise)--a disease caused by lack of physical activity leads among others to a predominance of the sympathetic nerve in the circulation. Its manifestations are briefly described according to Kraus-Raab's hypothesis of 1961. The opposite of a hypokinetic man are trained (hyperkinetic) sportsmen, in particular long-distance runners. Their neurovegetative balance is shifted to the side of the vagus (parasympathetic nerve). This is described as training vagotonia. On the example of ECG tracings of an Olympic 5 km runner, the Tunisian Mohamed Gammoudi, the author describes its manifestations at rest, during the orthostatic test and during work, i.e. the step test. These manifestations include in particular bradycardia of 32 beats per minute, prolonged atrioventricular conduction > 0.2 sec., a long period of the electric systole = 0.44 sec. and an enormously prolonged electric diastole T-P = 1.1 sec. This long diastolic filling stage makes it possible in particular during physical work to increase the systolic and diastolic output to double the values of a healthy non-trained heart. Training vagotonia is usually not the source for manifestation of dangerous arrhythmias, as it may be the case in constitutional vagotonia. So far expert comparison of these two types of change to parasympathic tonus is lacking, similarly as a comparative study with medicamentously influenced vagotonia by means of beta-blockers.

  3. Effect of adenosine cyclophosphate combined with vitamin C therapy on electrocardiogram and serum indexes of children with viral myocarditis

    Institute of Scientific and Technical Information of China (English)

    Jun Liao


    Objective:To study the effect of adenosine cyclophosphate combined with vitamin C therapy on electrocardiogram and serum indexes of children with viral myocarditis. Methods:A total of 110 cases of children with viral myocarditis treated in Pediatrics Department of our hospital from May 2012 to June 2914 were randomly divided into two groups, intervention group received adenosine cyclophosphate+vitamin C combined with conventional treatment, control group received conventional treatment, and then arrhythmia as well as serum myocardial enzymes, inflammatory mediators and signaling molecules of two groups were compared. Results: Cases with sinus tachycardia, premature beat, supraventricular tachycardia, atrioventricular block, sinus bradycardia, QT interval prolongation and ST-T segment change of intervention group were less than those of control group;serum aspartate transaminase, creatine kinase, creatine kinase isoenzyme, lactate dehydrogenase, α-hydroxybutyrate dehydrogenase, MIF, TNF-α, IL-1β, IL-6 and MCP-1 contents as well as mRNA expression levels of Rho and Rock of intervention group were lower than those of control group, and mRNA expression levels of JAK2 and STAT1 were higher than those of control group. Conclusion:Adenosine cyclophosphate combined with vitamin C therapy can prevent the occurrence of arrhythmia in children with viral myocarditis, protect myocardial cells, inhibit inflammatory response and regulate JAK2-STAT1signaling pathway and Rho/Rock signaling pathway.

  4. Attempted suicide by ingestion of chlorpyrifos: identification in serum and gastric content by GC-FID/GC-MS. (United States)

    Martínez, María A; Ballesteros, Salomé; Sánchez de la Torre, Carolina; Sanchiz, Antonio; Almarza, Elena; García-Aguilera, Alejandro


    A mild case of self-poisoning with a chlorpyrifos formulation following oral ingestion is reported. A 15-year-old female went to the emergency room after the ingestion of a product from a bottle marked with a label "Poison". On admission, she was obtunded, with normal vital signs and a strong smell of solvent. Therapeutic measures included the application of decontamination procedures, oxygen, and gastric protectors. She had a good outcome with mild CNS depression and bradycardia. Two hours after ingestion, biological samples were collected in the emergency room and sent for analysis to our laboratory with instructions to investigate the presence of solvents. The serum and gastric content contained 5.3 and 9.4 microg/mL of unmetabolized chlorpyrifos, 4.6 and 6.9 microg/mL of toluene, and 2.5 and 7.9 microg/mL of butyl acetate, respectively. Small traces of other solvents and tetradifon were also detected. Toxicological analyses were negative for ethanol, other volatile solvents, and common drugs of abuse. The simultaneous determination of chlorpyrifos, toluene, and butyl acetate was performed using the combination of gas chromatography (GC)-flame ionization detection for screening analysis and GC-mass spectrometry for confirmation of the obtained results. The method provides an excellent and rapid tool for use in cases of pesticide poisonings, allowing the simultaneous detection of the pesticide and distillates in the performance of systematic toxicological analysis in forensic and clinical laboratories.

  5. Parametric evaluation of methotrimeprazine-midazolam-ketamine and methotrimeprazine-midazolam-ketamine-xylazine combination in dogs

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    Santos Gustavo José Von Glehn dos


    Full Text Available PURPOSE: To evaluate the parameters of dogs anesthetized by different dissociative drugs protocols through continuous intravenous infusion. METHODS: Thirty healthy dogs of both sexes were assigned randomly to three groups (G1, G2, and G3. G1 was administered with methotrimeprazine as a pre-anesthetic medication, intravenously midazolam-ketamine as bolus for induction and midazolam-ketamine by continuous intravenous infusion for a 60 minute-period of maintenance. G2: the same as for G1. plus an increase in the midazolam dose during maintenance. G3: the same treatment as for G2, plus the addition of xylazine during maintenance. Immediately after induction the anesthetic maintenance started, and measures were taken 15 minutes after pre-medication, at 10 minutes intervals, during maintenance (M0 to M7. RESULTS: Bradycardia, atrioventricular blockage, bradypnea and hypoxemia were shown in G3. G1 and G2 showed a slight hypotension only. CONCLUSION: There were some advantages by using the continuous intravenous via: no parameters oscillation and reduction in the anesthetic recovery period. The increase in midazolam dose brought about little parametric variations which were greater when xylazine was used, with a consequent hypoxemia, bradyarrhytmia, and decrease in respiratory frequency and minute volume.

  6. A pragmatic comparison of noise burst and electric shock unconditioned stimuli for fear conditioning research with many trials. (United States)

    Sperl, Matthias F J; Panitz, Christian; Hermann, Christiane; Mueller, Erik M


    Several methods that are promising for studying the neurophysiology of fear conditioning (e.g., EEG, MEG) require a high number of trials to achieve an adequate signal-to-noise ratio. While electric shock and white noise burst are among the most commonly used unconditioned stimuli (US) in conventional fear conditioning studies with few trials, it is unknown whether these stimuli are equally well suited for paradigms with many trials. Here, N = 32 participants underwent a 260-trial differential fear conditioning and extinction paradigm with a 240-trial recall test 24 h later and neutral faces as conditioned stimuli. In a between-subjects design, either white noise bursts (n = 16) or electric shocks (n = 16) served as US, and intensities were determined using the most common procedure for each US (i.e., a fixed 95 dB noise burst and a work-up procedure for electric shocks, respectively). In addition to differing US types, groups also differed in closely linked US-associated characteristics (e.g., calibration methods, stimulus intensities, timing). Subjective ratings (arousal/valence), skin conductance, and evoked heart period changes (i.e., fear bradycardia) indicated more reliable, extinction-resistant, and stable conditioning in the white noise burst versus electric shock group. In fear conditioning experiments where many trials are presented, white noise burst should serve as US.

  7. [A brief history of the baroreceptor reflex: from Claude Bernard to Arthur C. Guyton. Illustrated with some classical experiments]. (United States)

    Estañol, Bruno; Porras-Betancourt, Manuel; Padilla-Leyva, Miguel Ángel; Sentíes-Madrid, Horacio


    The baroreceptor reflex is poorly known by most physicians even though is fundamental in stabilizing the blood pressure on a beat to beat basis and is crucial for survival. Its fascinating history is briefly reviewed in this article. In 1852 Claude Bernard discovered that the sympathetic nerves of the neck innervate the blood vessels of the skin of the rabbit. Edgar Douglas Adrian in 1932 demonstrated that the sympathetic nerves that innervate the blood vessels discharge spontaneously at a rate of 4-6 per second and thus discovered the physiological basis of the vasomotor tone. In the XIX century Ludwig Traube and Karl Constantine Ewald Hering discovered that blood pressure fluctuates synchronously with respiratory movements and Sigmund Mayer observed that there are also slow non respiratory fluctuations of blood pressure. In 1921 Heinrich Ewald Hering found that high pressure baroreceptors are located in the carotid sinuses and demonstrated that the stimulation of the afferent nerve that innervates it induces bradycardia and hypotension. These studies were further advanced by Corneille Heymans who won the Nobel Prize for these studies in 1938. Later Cowley and Guyton produced sino-aortic denervation in dogs and thereby could demonstrate the fundamental importance of the baroreceptor reflex in the stabilization of blood pressure.

  8. Effectiveness of propranolol in the treatment of infantile hemangioma beyond the proliferation phase. (United States)

    Vivas-Colmenares, Grecia V; Bernabeu-Wittel, Jose; Alonso-Arroyo, Veronica; Matute de Cardenas, Jose A; Fernandez-Pineda, Israel


    During the last 5 years, many studies have shown the efficacy of propranolol as first-line treatment for infantile hemangiomas (IHs), but not much has been written about the role of propranolol beyond the proliferation phase of IH (>1 year). Our aim was to assess propranolol efficacy and safety in the treatment of patients older than 1 year. A retrospective study of patients older than 1 year diagnosed with IH and treated in our vascular anomalies clinic between 2009 and 2013 was performed. Eighteen patients older than 1 year with a diagnosis of IH (15 girls, 3 boys) were identified. The mean age at the time of initiation of treatment was 25.7 months (range 13-72 mos). Single lesions were observed in 13 patients and multiple lesions in 5. Fifteen patients had focal lesions and three had segmental. The median duration of treatment with oral propranolol was 11.8 months (range 2-33 mos). Complete response was observed in 72.2% of the patients and partial response in 27.8%. Recurrence was observed in three patients 4.7 months after completion of therapy (range 0.3-8 mos). These patients required further therapy with propranolol for 6 more months. Bradycardia was documented in two patients and night terrors in one patient, which led to discontinuation of treatment. In our experience, propranolol may be useful in the treatment of IHs beyond the proliferation phase (>1 year old), but more studies are needed to support this observation.

  9. Pharmacokinetic-pharmacodynamic analyses of antihypertensive drugs, nifedipine and propranolol, in spontaneously hypertensive rats to investigate characteristics of effect and side effects. (United States)

    Kiriyama, Akiko; Honbo, Akino; Nishimura, Asako; Shibata, Nobuhito; Iga, Katsumi


    To investigate the relationship between the pharmacokinetics (PK) and effects and/or side-effects of nifedipine and propranolol, simultaneous examination of their PK and pharmacodynamics (PD), namely blood pressure (BP), heart rate (HR), and QT interval (QT), were assessed in spontaneously hypertensive rats as a disease model. Drugs were infused intravenously for 30 min, then plasma PK and hemodynamic effects were monitored. After general two-compartmental analysis was applied to the plasma data, PD parameters were calculated by fitting the data to PK-PD models. After nifedipine administration, the maximal hypotensive effect appeared about 10 min after starting the infusion, then BP started to elevate although the plasma concentration increased, supposedly because of a negative feedback mechanism generated from the homeostatic mechanism. After propranolol administration, HR decreased by half, and this bradycardic effect was greater than that with nifedipine. Wide variation in QT was observed when the propranolol concentration exceeded 700 ng/mL. This variation may have been caused by arrhythmia. Prolongation of QT with propranolol was greater than that with nifedipine, and bradycardia was slower than the concentration increase and QT prolongation. The characteristically designed PK-PD model incorporating a negative feedback system could be adequately and simultaneously fitted to both observed effect and side-effects.

  10. Circulatory responses to asphyxia differ if the asphyxia occurs in utero or ex utero in near-term lambs.

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    Kristina S Sobotka

    Full Text Available A cornerstone of neonatal resuscitation teaching suggests that a rapid vagal-mediated bradycardia is one of the first signs of perinatal compromise. As this understanding is based primarily on fetal studies, we investigated whether the heart rate and blood pressure response to total asphyxia is influenced by whether the animal is in utero or ex utero.Fetal sheep were instrumented at ∼ 139 days of gestation and then asphyxiated by umbilical cord occlusion until mean arterial blood pressure decreased to ∼ 20 mmHg. Lambs were either completely submerged in amniotic fluid (in utero; n = 8 throughout the asphyxia or were delivered and then remained ex utero (ex utero; n = 8 throughout the asphyxia. Heart rate and arterial blood pressure were continuously recorded.Heart rate was higher in ex utero lambs than in utero lambs. Heart rates in in utero lambs rapidly decreased, while heart rates in ex utero lambs initially increased following cord occlusion (for ∼ 1.5 min before they started to decrease. Mean arterial pressure initially increased then decreased in both groups.Heart rate response to asphyxia was markedly different depending upon whether the lamb was in utero or ex utero. This indicates that the cardiovascular responses to perinatal asphyxia are significantly influenced by the newborn's local environment. As such, based solely on heart rate, the stage and severity of a perinatal asphyxic event may not be as accurate as previously assumed.

  11. Fatal Overdose due to Confusion of an Transdermal Fentanyl Delivery System

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    Ingo Voigt


    Full Text Available Background. The use of transdermal fentanyl systems has increased over recent years, especially in patients with chronic pain. Large misuse potential and fatal outcomes have been described. Case Presentation. A 58-year-old patient presenting with clinical signs of opioid poisoning (hypoventilation, bradycardia, hypotension, and miosis was admitted to our ICU. The first body check revealed a 75 mcg per hour fentanyl patch at the patient's right scapula. Some months ago, patient's aunt died after suffering from an oncological disease. During breaking up of her household, the patches were saved by the patient. Not knowing the risk of this drug, he mistook it as a heat plaster. Investigations. Laboratory test showed an impaired renal function and metabolic acidosis. Urine drug test was negative at admittance and 12 h later. CCT scan presented a global hypoxic brain disease. Treatment and Outcome. The patient was discharged 30 days after admittance in a hemodynamic stable condition but a vegetative state and transferred to a rehabilitation center. Learning Points. With the ongoing increase in fentanyl patch prescriptions for therapeutic reasons, it is likely that misuse cases will become more relevant. Conventional urine drug screening tests are not able to exclude the diagnosis fentanyl intoxication. History taking should include family member's drug prescriptions.


    Directory of Open Access Journals (Sweden)

    Rangalakshmi S


    Full Text Available OBJECTIVE Lumbar spinal surgeries have been performed with either spinal or general anaesthesia. In this study, we aimed to evaluate the superiority of either spinal or general anaesthesia on lumbar spine surgery. METHODS After approval of institutional ethical committee, we retrospectively analysed 270 patients (ASA I and II undergoing surgery of lumbar spine from 2009 to 2015 by one surgeon. Of these 150 patients underwent general anaesthesia with controlled ventilation, 120 patients were offered spinal anaesthesia with conscious sedation. Patient records were reviewed to obtain demographic features, type of anaesthesia, baseline heart rate, mean arterial pressure, intraoperative maximum heart rate, mean arterial pressure, duration of surgery, amount of intravenous fluids, intraoperative blood loss, incidence of perioperative complications such as bleeding, nausea, vomiting, hypotension, bradycardia, and postoperative analgesic consumption. RESULTS Patient characteristics including baseline/intraoperative mean arterial pressure and heart rate values did not differ between groups. However, the spinal anaesthesia group experienced significantly shorter durations in the operating room and had a lower incidence of nausea, vomiting. Analgesic consumptions in general anaesthesia group was significantly higher than in spinal anaesthesia group. CONCLUSION The present study revealed that spinal anaesthesia is a safe and effective alternative to general anaesthesia for patients undergoing single level or two level lumbar laminectomy, discectomy, or even instrumentation below L2 level and has the advantage of decreased nausea, antiemetic, analgesic requirements, and fewer complications. It also ensures better postoperative recovery when compared to general anaesthesia

  13. Usefulness of bispectral monitoring of conscious sedation during endoscopic mucosal dissection

    Institute of Scientific and Technical Information of China (English)

    Kazunori Hata; Akira Andoh; Kiyoyuki Hayafuji; Atsuhiro Ogawa; Tamio Nakahara; Tomoyuki Tsujikawa; Yoshihide Fujiyama; Yasuharu Saito


    AIM: To assess the usefulness of bispectral index (BIS) monitoring in order to carry out endoscopic submucosal dissection (ESD) safely and with patients'satisfaction. METHODS: Three hundred sixty-six patients with an early-stage neoplasm of the digestive tract were enrolled. The BIS monitor (A-1050: Aspect medical systems/NIHON KOHDEN, Tokyo, Japan) was used. The appropriate sedative condition was set at 55 to 75 BIS levels (BIS value) during the endoscopic procedures.RESULTS: Among 366 cases, 13 were accompanied by adverse events during and/or after ESD. All episodes occurred in cases with BIS value between 56 and 65. Hypotension was observed in four cases, and bradycardia in six. Respiratory distress was observed in two cases with chronic pulmonary obstructive disease. All patients with adverse events were able to leave the hospital without extension of the hospitalization. CONCLUSION: BIS monitoring is useful to safely perform ESD. A BIS value of 70 to 75 is suitable for ESD.

  14. Smart Multi-Level Tool for Remote Patient Monitoring Based on a Wireless Sensor Network and Mobile Augmented Reality

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    Fernando Cornelio Jiménez González


    Full Text Available Technological innovations in the field of disease prevention and maintenance of patient health have enabled the evolution of fields such as monitoring systems. One of the main advances is the development of real-time monitors that use intelligent and wireless communication technology. In this paper, a system is presented for the remote monitoring of the body temperature and heart rate of a patient by means of a wireless sensor network (WSN and mobile augmented reality (MAR. The combination of a WSN and MAR provides a novel alternative to remotely measure body temperature and heart rate in real time during patient care. The system is composed of (1 hardware such as Arduino microcontrollers (in the patient nodes, personal computers (for the nurse server, smartphones (for the mobile nurse monitor and the virtual patient file and sensors (to measure body temperature and heart rate, (2 a network layer using WiFly technology, and (3 software such as LabView, Android SDK, and DroidAR. The results obtained from tests show that the system can perform effectively within a range of 20 m and requires ten minutes to stabilize the temperature sensor to detect hyperthermia, hypothermia or normal body temperature conditions. Additionally, the heart rate sensor can detect conditions of tachycardia and bradycardia.

  15. Smart multi-level tool for remote patient monitoring based on a wireless sensor network and mobile augmented reality. (United States)

    González, Fernando Cornelio Jiménez; Villegas, Osslan Osiris Vergara; Ramírez, Dulce Esperanza Torres; Sánchez, Vianey Guadalupe Cruz; Domínguez, Humberto Ochoa


    Technological innovations in the field of disease prevention and maintenance of patient health have enabled the evolution of fields such as monitoring systems. One of the main advances is the development of real-time monitors that use intelligent and wireless communication technology. In this paper, a system is presented for the remote monitoring of the body temperature and heart rate of a patient by means of a wireless sensor network (WSN) and mobile augmented reality (MAR). The combination of a WSN and MAR provides a novel alternative to remotely measure body temperature and heart rate in real time during patient care. The system is composed of (1) hardware such as Arduino microcontrollers (in the patient nodes), personal computers (for the nurse server), smartphones (for the mobile nurse monitor and the virtual patient file) and sensors (to measure body temperature and heart rate), (2) a network layer using WiFly technology, and (3) software such as LabView, Android SDK, and DroidAR. The results obtained from tests show that the system can perform effectively within a range of 20 m and requires ten minutes to stabilize the temperature sensor to detect hyperthermia, hypothermia or normal body temperature conditions. Additionally, the heart rate sensor can detect conditions of tachycardia and bradycardia.

  16. Problems associated with the apnea test in the diagnosis of brain death

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    Saposnik Gustavo


    Full Text Available Background: Brain death is the absence of all cortical functions, including the brainstem. The apnea test (AT is a necessary requisite to complete this diagnosis. Anecdotal reports describing hypotension and acidosis due to apnea test have been reported. However, there are few studies that evaluate complications or difficulties related to this procedure. Objective: To analyze medical problems associated with the apnea test. Methods and Patients: We analyzed clinical features, potential risk conditions, and problems in 129 brain dead patients during the apnea test. The diagnosis of brain death was made according to the American Academy of Neurology recommendations. Results: Clinical problems during the apnea test were detected in more than two thirds of patients, including: arterial hypotension (12%, acidosis (68%, and hypoxemia (23%. Four patients developed major complications, including: pneumothorax, cardiac arrest, bradycardia, atrial fibrillation and myocardial infarction. Conclusion: The apnea test is not an innocuous procedure. Complications during the AT are more common than reported and limit organ procurement for transplantation. Guidelines for performing the AT should be followed in order to avoid clinical complications.

  17. Low-dose (1 microg/kg) clonidine premedication and hypotension after carotid artery surgery. (United States)

    Pandazi, Ageliki; Karamanis, Periandros; Sidiropoulou, Tatiana; Matsota, Paraskevi; Papasideris, Christos; Niokou, Dimitra; Kostopanagiotou, Georgia


    We investigated the role of low-dose clonidine intravenous (IV) premedication in arterial pressure variation during and after carotid endarterectomy (CEA). A total of 84 patients, American Society of Anesthesiologists (ASA) II-III, scheduled for elective CEA under general anesthesia participated in this study. The patients were divided into 2 groups: group P (n = 42) and group C (n = 42) and received N/S 0.9% (placebo) or clonidine 1 μg/kg IV, respectively, 15 minutes before induction of anesthesia. Recovery times, number of patients needed to be treated for circulatory events (hypertension, hypotension, and bradycardia), number of circulatory events per patient, and consumption of vasoactive drugs (nitroglycerine, phenylphrine, and atropine) intraoperatively and the first 6 hours postoperatively were recorded. Significantly less hypertensive episodes were observed intraoperatively, but more hypotensive episodes were observed postoperatively in patients receiving clonidine. Intravenous premedication with low-dose clonidine (1 μg/kg) seems to be effective in preventing hypertensive episodes during CEA under general anesthesia but seems to increase the incidence of hypotension postoperatively.

  18. Linalool-rich rosewood oil induces vago-vagal bradycardic and depressor reflex in rats. (United States)

    de Siqueira, Rodrigo José; Rodrigues, Karilane Maria Silvino; da Silva, Moisés Tolentino Bento; Correia Junior, Carlos Antônio Barros; Duarte, Gloria Pinto; Magalhães, Pedro Jorge Caldas; dos Santos, Armênio Aguiar; Maia, José Guilherme Soares; da Cunha, Pergentino José Sousa; Lahlou, Saad


    Cardiovascular effects of the linalool-rich essential oil of Aniba rosaeodora (here named as EOAR) in normotensive rats were investigated. In anesthetized rats, intravenous (i.v.) injection of EOAR induced dose-dependent biphasic hypotension and bradycardia. Emphasis was given to the first phase (phase 1) of the cardiovascular effects, which is rapid (onset time of 1-3 s) and not observed in animals submitted to bilateral vagotomy or selective blockade of neural conduction of vagal C-fibre afferents by perineural treatment with capsaicin. Phase 1 was also absent when EOAR was directly injected into the left ventricle injection, but it was unaltered by i.v. pretreatment with capsazepine, ondansetron or HC030031. In conscious rats, EOAR induced rapid and monophasic hypotensive and bradycardiac (phase 1) effects that were abolished by i.v. methylatropine. In endothelium-intact aortic rings, EOAR fully relaxed phenylephrine-induced contractions in a concentration-dependent manner. The present findings reveal that phase 1 of the bradycardiac and depressor responses induced by EOAR has a vago-vagal reflex origin resulting from the vagal pulmonary afferents stimulation. Such phenomenon appears not to involve the recruitment of C-fibre afferents expressing 5HT3 receptors or the two chemosensory ion channels TRPV1 and TRPA1 . Phase 2 hypotensive response appears resulting from a direct vasodilatory action.

  19. Silicon-containing nanocarriers for targeted drug delivery: synthesis, physicochemical properties and acute toxicity. (United States)

    Sonin, Dmitry L; Korolev, Dmitry V; Postnov, Viktor N; Naumysheva, Elena B; Pochkaeva, Evgenia I; Vasyutina, Marina L; Galagudza, Michael M


    Silicon-containing nanoparticles (NPs) are considered promising drug carriers for targeted drug delivery. In this study, we investigated the physical and chemical properties of silicon-containing NPs, including silica and organomodified silica NPs (SiO2NPs and OrSiO2NPs, respectively), with different surface modifications, with the aim of increasing drug-loading efficiency. In addition, we described the original synthesis methods of different sizes of OrSiO2NPs, as well as new hybrid OrSiO2NPs with a silica core (SiO2 + OrSiO2NPs). Animal experiments revealed that the silicon-containing NPs investigated were non-toxic, as evidenced by a lack of hemodynamic response after intravenous administration. Bioelimination studies showed rapid renal excretion of OrSiO2NPs. In drug release kinetics studies, adenosine was immobilized on SiO2NPs using three different approaches: physical adsorption, ionic, and covalent bonding. We observed that the rate of adenosine desorption critically depended on the type of immobilization; therefore, adenosine release kinetics can be adjusted by SiO2NP surface modification technique. Adsorption of adenosine on SiO2 + OrSiO2NPs resulted in a significant attenuation of adenosine-induced hypotension and bradycardia.

  20. Cerebral Hemispheric Lateralization Associated with Hippocampal Sclerosis May Affect Interictal Cardiovascular Autonomic Functions in Temporal Lobe Epilepsy

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    Rokia Ghchime


    Full Text Available It is well established that the temporal lobe epilepsy (TLE is linked to the autonomic nervous system dysfunctions. Seizures alter the function of different systems such as the respiratory, cardiovascular, gastrointestinal, and urogenital systems. The aim of this work was to evaluate the possible factors which may be involved in interictal cardiovascular autonomic function in temporal lobe epilepsy with complex partial seizures, and with particular attention to hippocampal sclerosis. The study was conducted in 30 patients with intractable temporal lobe epilepsy (19 with left hippocampal sclerosis, 11 with right hippocampal sclerosis. All subjects underwent four tests of cardiac autonomic function: heart rate changes in response to deep breathing, heart rate, and blood pressure variations throughout resting activity and during hand grip, mental stress, and orthostatic tests. Our results show that the right cerebral hemisphere predominantly modulates sympathetic activity, while the left cerebral hemisphere mainly modulates parasympathetic activity, which mediated tachycardia and excessive bradycardia counterregulation, both of which might be involved as a mechanism of sudden unexpected death in epilepsy patients (SUDEP.