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Sample records for cardiac repolarization abnormalities

  1. Cardiac Repolarization Abnormalities and Potential Evidence for Loss of Cardiac Sodium Currents on ECGs of Patients with Chagas' Heart Disease

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    Schlegel, T. T.; Medina, R.; Jugo, D.; Nunez, T. J.; Borrego, A.; Arellano, E.; Arenare, B.; DePalma, J. L.; Greco, E. C.; Starc, V.

    2007-01-01

    were not significantly different between groups. Patients with Chagas heart disease have increased cardiac repolarization abnormalities, especially by advanced ECG. Moreover, as a group, they have decreased uncorrected JT and QT interval durations and increased filtered QRS interval durations (versus age/gender-matched controls), all suggesting a potential loss of cardiac sodium channel function that might be mediated, in part, by cardiac autonomic damage. Overall findings support Brugada et al's recent hypothesis that the pathway leading to sudden death may often be similar in Chagas' disease and Brugada syndrome i.e., damage to the sodium channel (infectious/immunologic/autonomic in Chagas' genetic in Brugada) with consequent loss of sodium currents may facilitate a phase II-reentry based arrhythmic substrate for ventricular fibrillation in both conditions. In general, JT interval-related results have been underreported in the Chagas literature.

  2. Quantitative analysis of T-wave morphology increases confidence in drug-induced cardiac repolarization abnormalities: evidence from the investigational IKr inhibitor Lu 35-138

    DEFF Research Database (Denmark)

    Graff, Claus; Matz, Jørgen; Christensen, Ellen B;

    2009-01-01

    to determine a combined measure of repolarization morphology (morphology combination score [MCS]), based on asymmetry, flatness, and notching. Replicate measurements were used to determine reliable change and study power for both measures. Lu 35-138 increased the QTc interval with corresponding changes in T...... was 93%. As a covariate to the assessment of QT interval liability, MCS offered important additive information to the effect of Lu 35-138 on cardiac repolarization....

  3. Major rapid weight loss induces changes in cardiac repolarization

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    Vedel-Larsen, Esben; Iepsen, Eva Winning; Lundgren, Julie

    2016-01-01

    INTRODUCTION: Obesity is associated with increased all-cause mortality, but weight loss may not decrease cardiovascular events. In fact, very low calorie diets have been linked to arrhythmias and sudden death. The QT interval is the standard marker for cardiac repolarization, but T-wave morphology...... analysis has been suggested as a more sensitive method to identify changes in cardiac repolarization. We examined the effect of a major and rapid weight loss on T-wave morphology. METHODS AND RESULTS: Twenty-six individuals had electrocardiograms (ECG) taken before and after eight weeks of weight loss......A1c (pweight loss induces changes in cardiac repolarization. Monitoring of MCS during calorie restriction makes it possible to detect repolarization changes with higher discriminative power than the QT-interval during major rapid weight...

  4. Probing cardiac repolarization reserve in drug safety assessment

    NARCIS (Netherlands)

    Nalos, L.

    2011-01-01

    Excessive prolongation of cardiac repolarization, manifested as QT prolongation on ECG, is common unwanted side effect of many drugs and drug candidates. Prolongation of QT interval may lead to life threatening cardiac arrhythmia – Torsade de Point (TdP). Number of drugs was withdrawn from the marke

  5. Faulty cardiac repolarization reserve in alternating hemiplegia of childhood broadens the phenotype.

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    Jaffer, Fatima; Avbersek, Andreja; Vavassori, Rosaria; Fons, Carmen; Campistol, Jaume; Stagnaro, Michela; De Grandis, Elisa; Veneselli, Edvige; Rosewich, Hendrik; Gianotta, Melania; Zucca, Claudio; Ragona, Francesca; Granata, Tiziana; Nardocci, Nardo; Mikati, Mohamed; Helseth, Ashley R; Boelman, Cyrus; Minassian, Berge A; Johns, Sophia; Garry, Sarah I; Scheffer, Ingrid E; Gourfinkel-An, Isabelle; Carrilho, Ines; Aylett, Sarah E; Parton, Matthew; Hanna, Michael G; Houlden, Henry; Neville, Brian; Kurian, Manju A; Novy, Jan; Sander, Josemir W; Lambiase, Pier D; Behr, Elijah R; Schyns, Tsveta; Arzimanoglou, Alexis; Cross, J Helen; Kaski, Juan P; Sisodiya, Sanjay M

    2015-10-01

    Alternating hemiplegia of childhood is a rare disorder caused by de novo mutations in the ATP1A3 gene, expressed in neurons and cardiomyocytes. As affected individuals may survive into adulthood, we use the term 'alternating hemiplegia'. The disorder is characterized by early-onset, recurrent, often alternating, hemiplegic episodes; seizures and non-paroxysmal neurological features also occur. Dysautonomia may occur during hemiplegia or in isolation. Premature mortality can occur in this patient group and is not fully explained. Preventable cardiorespiratory arrest from underlying cardiac dysrhythmia may be a cause. We analysed ECG recordings of 52 patients with alternating hemiplegia from nine countries: all had whole-exome, whole-genome, or direct Sanger sequencing of ATP1A3. Data on autonomic dysfunction, cardiac symptoms, medication, and family history of cardiac disease or sudden death were collected. All had 12-lead electrocardiogram recordings available for cardiac axis, cardiac interval, repolarization pattern, and J-point analysis. Where available, historical and prolonged single-lead electrocardiogram recordings during electrocardiogram-videotelemetry were analysed. Half the cohort (26/52) had resting 12-lead electrocardiogram abnormalities: 25/26 had repolarization (T wave) abnormalities. These abnormalities were significantly more common in people with alternating hemiplegia than in an age-matched disease control group of 52 people with epilepsy. The average corrected QT interval was significantly shorter in people with alternating hemiplegia than in the disease control group. J wave or J-point changes were seen in six people with alternating hemiplegia. Over half the affected cohort (28/52) had intraventricular conduction delay, or incomplete right bundle branch block, a much higher proportion than in the normal population or disease control cohort (P = 0.0164). Abnormalities in alternating hemiplegia were more common in those ≥16 years old, compared

  6. Early repolarization syndrome: A cause of sudden cardiac death

    Institute of Scientific and Technical Information of China (English)

    Abdi; Ali; Nida; Butt; Azeem; S; Sheikh

    2015-01-01

    Early repolarization syndrome(ERS), demonstrated as J-point elevation on an electrocardiograph, was formerly thought to be a benign entity, but the recent studies have demonstrated that it can be linked to a considerable risk of life- threatening arrhythmias and sudden cardiac death(SCD). Early repolarization characteristics associated with SCD include high-amplitude J-point elevation, horizontal and/or downslopping ST segments, and inferior and/or lateral leads location. The prevalence of ERS varies between 3% and 24%, depending on age, sex and J-point elevation(0.05 m V vs 0.1 m V) being the main determinants.ERS patients are sporadic and they are at a higher risk of having recurrent cardiac events. Implantable cardioverter-defibrillator implantation and isoproterenol are the suggested therapies in this set of patients. On the other hand, asymptomatic patients with ERS are common and have a better prognosis. The risk stratification in asymptomatic patients with ERS still remains a grey area. This review provides an outline of the up-to-date evidence associated with ERS and the risk of life- threatening arrhythmias. Further prospective studies are required to elucidate the mechanisms of ventricular arrhythmogenesis in patients with ERS.

  7. Rosuvastatin blocks hERG current and prolongs cardiac repolarization.

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    Plante, Isabelle; Vigneault, Patrick; Drolet, Benoît; Turgeon, Jacques

    2012-02-01

    Blocking of the potassium current I(Kr) [human ether-a-go-go related gene (hERG)] is generally associated with an increased risk of long QT syndrome (LQTS). The 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitor, rosuvastatin, is a methanesulfonamide derivative, which shows structural similarities with several I(Kr) blockers. Hence, we assessed the effects of rosuvastatin on cardiac repolarization by using in vitro, ex vivo, and in vivo models. Patch clamp experiments on hERG-transfected human embryonic kidney (HEK) 293 cells established the potency of rosuvastatin to block hERG [half maximal inhibitory concentration (IC(50) ) = 195 nM]. We showed in isolated guinea pig hearts that 195 nM rosuvastatin prolonged (basic cycle length of 250 ms; p cancer resistance protein (BCRP), multidrug resistance gene (MDR1)] and influx [organic anion transporting polypeptide (OATP) 2B1] transporters involved in the disposition and cardiac distribution of the drug. Genetic polymorphisms observed for BCRP, MDR1, and OATP2B1, and IC(50) determined for hERG blocking lead us to propose that some patients may be at risk of rosuvastatin-induced LQTS.

  8. Utility of hERG assays as surrogate markers of delayed cardiac repolarization and QT safety.

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    Gintant, Gary A; Su, Zhi; Martin, Ruth L; Cox, Bryan F

    2006-01-01

    HERG (human-ether-a-go-go-related gene) encodes for a cardiac potassium channel that plays a critical role in defining ventricular repolarization. Noncardiovascular drugs associated with a rare but potentially lethal ventricular arrhythmia (Torsades de Pointes) have been linked to delayed cardiac repolarization and block of hERG current. This brief overview will discuss the role of hERG current in cardiac electrophysiology, its involvement in drug-induced delayed repolarization, and approaches used to define drug effects on hERG current. In addition, examples of hERG blocking drugs acting differently (i.e., overt and covert hERG blockade due to multichannel block) together with the utility and limitations of hERG assays as tools to predict the risk of delayed repolarization and proarrhythmia are discussed.

  9. Spatial repolarization heterogeneity detected by magnetocardiography correlates with cardiac iron overload and adverse cardiac events in beta-thalassemia major.

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    Chun-An Chen

    Full Text Available BACKGROUND: Patients with transfusion-dependent beta-thalassemia major (TM are at risk for myocardial iron overload and cardiac complications. Spatial repolarization heterogeneity is known to be elevated in patients with certain cardiac diseases, but little is known in TM patients. The purpose of this study was to evaluate spatial repolarization heterogeneity in patients with TM, and to investigate the relationships between spatial repolarization heterogeneity, cardiac iron load, and adverse cardiac events. METHODS AND RESULTS: Fifty patients with TM and 55 control subjects received 64-channel magnetocardiography (MCG to determine spatial repolarization heterogeneity, which was evaluated by a smoothness index of QTc (SI-QTc, a standard deviation of QTc (SD-QTc, and a QTc dispersion. Left ventricular function and myocardial T2* values were assessed by cardiac magnetic resonance. Patients with TM had significantly greater SI-QTc, SD-QTc, and QTc dispersion compared to the control subjects (all p values<0.001. Spatial repolarization heterogeneity was even more pronounced in patients with significant iron overload (T2*<20 ms, n = 20 compared to those with normal T2* (all p values<0.001. Loge cardiac T2* correlated with SI-QTc (r = -0.609, p<0.001, SD-QTc (r = -0.572, p<0.001, and QTc dispersion (r = -0.622, p<0.001, while all these indices had no relationship with measurements of the left ventricular geometry or function. At the time of study, 10 patients had either heart failure or arrhythmia. All 3 indices of repolarization heterogeneity were related to the presence of adverse cardiac events, with areas under the receiver operating characteristic curves (ranged between 0.79 and 0.86, similar to that of cardiac T2*. CONCLUSIONS: Multichannel MCG demonstrated that patients with TM had increased spatial repolarization heterogeneity, which is related to myocardial iron load and adverse cardiac events.

  10. Cardiac repolarization during hypoglycaemia and hypoxaemia in healthy males: impact of renin-angiotensin system activity

    DEFF Research Database (Denmark)

    Due-Andersen, Rikke; Høi-Hansen, Thomas; Olsen, Niels Vidiendal;

    2008-01-01

    AIMS: Activity in the renin-angiotensin system (RAS) may influence the susceptibility to cardiac arrhythmia. To study the effect of basal RAS activity on cardiac repolarization during myocardial stress induced by hypoglycaemia or hypoxaemia in healthy humans. METHODS AND RESULTS: Ten subjects...

  11. Na/K pump regulation of cardiac repolarization: insights from a systems biology approach

    KAUST Repository

    Bueno-Orovio, Alfonso

    2013-05-15

    The sodium-potassium pump is widely recognized as the principal mechanism for active ion transport across the cellular membrane of cardiac tissue, being responsible for the creation and maintenance of the transarcolemmal sodium and potassium gradients, crucial for cardiac cell electrophysiology. Importantly, sodium-potassium pump activity is impaired in a number of major diseased conditions, including ischemia and heart failure. However, its subtle ways of action on cardiac electrophysiology, both directly through its electrogenic nature and indirectly via the regulation of cell homeostasis, make it hard to predict the electrophysiological consequences of reduced sodium-potassium pump activity in cardiac repolarization. In this review, we discuss how recent studies adopting the systems biology approach, through the integration of experimental and modeling methodologies, have identified the sodium-potassium pump as one of the most important ionic mechanisms in regulating key properties of cardiac repolarization and its rate dependence, from subcellular to whole organ levels. These include the role of the pump in the biphasic modulation of cellular repolarization and refractoriness, the rate control of intracellular sodium and calcium dynamics and therefore of the adaptation of repolarization to changes in heart rate, as well as its importance in regulating pro-arrhythmic substrates through modulation of dispersion of repolarization and restitution. Theoretical findings are consistent across a variety of cell types and species including human, and widely in agreement with experimental findings. The novel insights and hypotheses on the role of the pump in cardiac electrophysiology obtained through this integrative approach could eventually lead to novel therapeutic and diagnostic strategies. © 2013 Springer-Verlag Berlin Heidelberg.

  12. Cardiac repolarization during hypoglycaemia in type 1 diabetes: impact of basal renin-angiotensin system activity

    DEFF Research Database (Denmark)

    Due-Andersen, Rikke; Høi-Hansen, Thomas; Larroude, Charlotte Ellen;

    2008-01-01

    activity affects cardiac repolarization during hypoglycaemia, thereby potentially carrying prognostic information on risk of the 'dead-in-bed syndrome'. METHODS AND RESULTS: Nine subjects with high RAS activity and nine subjects with low RAS activity were subjected to single-blinded placebo...

  13. Ionic mechanisms limiting cardiac repolarization reserve in humans compared to dogs.

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    Jost, Norbert; Virág, László; Comtois, Philippe; Ordög, Balázs; Szuts, Viktória; Seprényi, György; Bitay, Miklós; Kohajda, Zsófia; Koncz, István; Nagy, Norbert; Szél, Tamás; Magyar, János; Kovács, Mária; Puskás, László G; Lengyel, Csaba; Wettwer, Erich; Ravens, Ursula; Nánási, Péter P; Papp, Julius Gy; Varró, András; Nattel, Stanley

    2013-09-01

    The species-specific determinants of repolarization are poorly understood. This study compared the contribution of various currents to cardiac repolarization in canine and human ventricle. Conventional microelectrode, whole-cell patch-clamp, molecular biological and mathematical modelling techniques were used. Selective IKr block (50-100 nmol l(-1) dofetilide) lengthened AP duration at 90% of repolarization (APD90) >3-fold more in human than dog, suggesting smaller repolarization reserve in humans. Selective IK1 block (10 μmol l(-1) BaCl2) and IKs block (1 μmol l(-1) HMR-1556) increased APD90 more in canine than human right ventricular papillary muscle. Ion current measurements in isolated cardiomyocytes showed that IK1 and IKs densities were 3- and 4.5-fold larger in dogs than humans, respectively. IKr density and kinetics were similar in human versus dog. ICa and Ito were respectively ~30% larger and ~29% smaller in human, and Na(+)-Ca(2+) exchange current was comparable. Cardiac mRNA levels for the main IK1 ion channel subunit Kir2.1 and the IKs accessory subunit minK were significantly lower, but mRNA expression of ERG and KvLQT1 (IKr and IKs α-subunits) were not significantly different, in human versus dog. Immunostaining suggested lower Kir2.1 and minK, and higher KvLQT1 protein expression in human versus canine cardiomyocytes. IK1 and IKs inhibition increased the APD-prolonging effect of IKr block more in dog (by 56% and 49%, respectively) than human (34 and 16%), indicating that both currents contribute to increased repolarization reserve in the dog. A mathematical model incorporating observed human-canine ion current differences confirmed the role of IK1 and IKs in repolarization reserve differences. Thus, humans show greater repolarization-delaying effects of IKr block than dogs, because of lower repolarization reserve contributions from IK1 and IKs, emphasizing species-specific determinants of repolarization and the limitations of animal models for

  14. Identifying drug-induced repolarization abnormalities from distinct ECG patterns in congenital long QT syndrome: a study of sotalol effects on T-wave morphology

    DEFF Research Database (Denmark)

    Graff, Claus; Andersen, Mads P; Xue, Joel Q

    2009-01-01

    BACKGROUND: The electrocardiographic QT interval is used to identify drugs with potential harmful effects on cardiac repolarization in drug trials, but the variability of the measurement can mask drug-induced ECG changes. The use of complementary electrocardiographic indices of abnormal repolariz......BACKGROUND: The electrocardiographic QT interval is used to identify drugs with potential harmful effects on cardiac repolarization in drug trials, but the variability of the measurement can mask drug-induced ECG changes. The use of complementary electrocardiographic indices of abnormal...... are typical ECG patterns in LQT2. Blinded to labels, the new morphology measures were tested in a third group of 39 healthy subjects receiving sotalol. Over 3 days the sotalol group received 0, 160 and 320 mg doses, respectively, and a 12-lead Holter ECG was recorded for 22.5 hours each day. Drug...... with QTcF, p ECG patterns in LQT2 carriers effectively quantified repolarization changes induced by sotalol. Further studies are needed to validate whether this measure has...

  15. Cardiac abnormalities after subarachnoid hemorrhage

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    Bilt, I.A.C. van der

    2016-01-01

    Aneurysmal subarachnoid hemorrhage(aSAH) is a devastating neurological disease. During the course of the aSAH several neurological and medical complications may occur. Cardiac abnormalities after aSAH are observed often and resemble stress cardiomyopathy or Tako-tsubo cardiomyopathy(Broken Heart Syn

  16. Sudden cardiac death in dogs with remodeled hearts is associated with larger beat-to-beat variability of repolarization

    DEFF Research Database (Denmark)

    Thomsen, Morten Bækgaard; Truin, Michiel; van Opstal, Jurren M

    2005-01-01

    Increased proarrhythmia in dogs with chronic AV block (AVB) has been explained by ventricular remodeling causing a decrease in repolarization reserve. Beat-to-beat variability of repolarization (BVR) has been suggested to reflect repolarization reserve, in which high variability represents...... diminished reserve and larger propensity for repolarization-dependent ventricular arrhythmia. A subset of chronic AVB dogs (10%) suffers sudden cardiac death (SCD). With the assumption that repolarization defects constitute a potentially lethal proarrhythmic substrate, we hypothesized that BVR in SCD dogs...... are larger than in matched control chronic AVB dogs. From a population of 200 chronic AVB dogs, initially two groups were chosen retrospectively: 8 dogs that died suddenly (SCD) and 8 control dogs. Control dogs had a longer lifespan after AVB (10 to 18 weeks) than SCD dogs (5 to 10 weeks). All dogs had...

  17. Covariate analysis of QTc and T-wave morphology: new possibilities in the evaluation of drugs that affect cardiac repolarization

    DEFF Research Database (Denmark)

    Graff, Claus; Struijk, Johannes J.; Matz, J;

    2010-01-01

    This study adds the dimension of a T-wave morphology composite score (MCS) to the QTc interval-based evaluation of drugs that affect cardiac repolarization. Electrocardiographic recordings from 62 subjects on placebo and 400 mg moxifloxacin were compared with those from 21 subjects on 160 and 320...

  18. Prevention of Pazopanib-Induced Prolonged Cardiac Repolarization and Proarrhythmic Effects

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    Tulay Akman

    2014-11-01

    Full Text Available Background: Pazopanib (PZP may induce prolonged cardiac repolarization and proarrhythmic effects, similarly to other tyrosine kinase inhibitors. Objectives: To demonstrate PZP-induced prolonged cardiac repolarization and proarrhythmic electrophysiological effects and to investigate possible preventive effects of metoprolol and diltiazem on ECG changes (prolonged QT in an experimental rat model. Methods: Twenty-four Sprague-Dawley adult male rats were randomly assigned to 4 groups (n = 6. The first group (normal group received 4 mL of tap water and the other groups received 100 mg/kg of PZP (Votrient® tablet perorally, via orogastric tubes. After 3 hours, the following solutions were intraperitoneally administered to the animals: physiological saline solution (SP, to the normal group and to the second group (control-PZP+SP group; 1 mg/kg metoprolol (Beloc, Ampule, AstraZeneca, to the third group (PZP+metoprolol group; and 1mg/kg diltiazem (Diltiazem, Mustafa Nevzat, to the fourth group (PZP+diltiazem group. One hour after, and under anesthesia, QTc was calculated by recording ECG on lead I. Results: The mean QTc interval values were as follows: normal group, 99.93 ± 3.62 ms; control-PZP+SP group, 131.23 ± 12.21 ms; PZP+metoprolol group, 89.36 ± 3.61 ms; and PZP+diltiazem group, 88.86 ± 4.04 ms. Both PZP+metoprolol and PZP+diltiazem groups had significantly shorter QTc intervals compared to the control-PZP+SP group (p < 0.001. Conclusion: Both metoprolol and diltiazem prevented PZP-induced QT interval prolongation. These drugs may provide a promising prophylactic strategy for the prolonged QTc interval associated with tyrosine kinase inhibitor use.

  19. Evaluation of the effect on cardiac repolarization (QTc interval) of oncologic drugs.

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    Morganroth, J

    2007-01-01

    The 12-lead electrocardiograph (ECG) is the standard safety measurement used in clinical trials to identify drug-induced cardiac adverse effects. Drug-induced prolongation of the QTc interval (the measure of cardiac repolarization change), when excessive and in conjunction with the right risk factors, can degenerate into a polymorphic ventricular tachycardia called torsades de pointes and has become a new focus for new drug development. The assessment of an ECG in clinical practice using machine-defined QTc duration is intrinsically unreliable. Current regulatory concepts have focused on the need for measuring ECG intervals using manual techniques using digital processing in a central ECG laboratory. The QT interval is subject to a large degree of spontaneous variability requiring attention to basic clinical trial design issues such as sample size (use as large a cohort as possible), frequency of measurements taken (at least three to six ECGs at baseline and at many time points on therapy with pharmacokinetic samples if possible), and their accuracy. Since most oncologic products are cytotoxic, a Thorough or Dedicated ECG Trial cannot be conducted and in the usual trail, especially in phase I, all changes seen on the ECG will be attributed to the new oncology drug. For most nononcologic drugs, there is regulatory guidance on how much an effect on QTc duration might be related to the risk of cardiac toxicity. For oncology products, the central tendency magnitude and proportion of outliers needs to be well defined to construct a label if the risk-benefit analysis leads to marketing approval. Clinical cardiac findings such as syncope, ventricular tachyarrhythmias, and other cardiac effects will be important in this analysis.

  20. Assessing common classification methods for the identification of abnormal repolarization using indicators of T-wave morphology and QT interval

    DEFF Research Database (Denmark)

    Shakibfar, Saeed; Graff, Claus; Ehlers, Lars Holger;

    2012-01-01

    volunteers and LQT2 carriers were used to train classification algorithms using measures of T-wave morphology and QTc. The ability to correctly classify a third group of test subjects before and after receiving d,l-sotalol was evaluated using classification rules derived from training. As a single......Various parameters based on QTc and T-wave morphology have been shown to be useful discriminators for drug induced I(Kr)-blocking. Using different classification methods this study compares the potential of these two features for identifying abnormal repolarization on the ECG. A group of healthy...

  1. Electrocardiographic abnormalities and cardiac arrhythmias in structural brain lesions.

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    Katsanos, Aristeidis H; Korantzopoulos, Panagiotis; Tsivgoulis, Georgios; Kyritsis, Athanassios P; Kosmidou, Maria; Giannopoulos, Sotirios

    2013-07-31

    Cardiac arrhythmias and electrocardiographic abnormalities are frequently observed after acute cerebrovascular events. The precise mechanism that leads to the development of these arrhythmias is still uncertain, though increasing evidence suggests that it is mainly due to autonomic nervous system dysregulation. In massive brain lesions sympathetic predominance and parasympathetic withdrawal during the first 72 h are associated with the occurrence of severe secondary complications in the first week. Right insular cortex lesions are also related with sympathetic overactivation and with a higher incidence of electrocardiographic abnormalities, mostly QT prolongation, in patients with ischemic stroke. Additionally, female sex and hypokalemia are independent risk factors for severe prolongation of the QT interval which subsequently results in malignant arrhythmias and poor outcome. The prognostic value of repolarization changes commonly seen after aneurysmal subarachnoid hemorrhage, such as ST segment, T wave, and U wave abnormalities, still remains controversial. In patients with traumatic brain injury both intracranial hypertension and cerebral hypoperfusion correlate with low heart rate variability and increased mortality. Given that there are no firm guidelines for the prevention or treatment of the arrhythmias that appear after cerebral incidents this review aims to highlight important issues on this topic. Selected patients with the aforementioned risk factors could benefit from electrocardiographic monitoring, reassessment of the medications that prolong QTc interval, and administration of antiadrenergic agents. Further research is required in order to validate these assumptions and to establish specific therapeutic strategies.

  2. MiRNA-1/133a clusters regulate adrenergic control of cardiac repolarization.

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    Johannes Besser

    Full Text Available The electrical properties of the heart are primarily determined by the activity of ion channels and the activity of these molecules is permanently modulated and adjusted to the physiological needs by adrenergic signaling. miRNAs are known to control the expression of many proteins and to fulfill distinct functions in the mammalian heart, though the in vivo effects of miRNAs on the electrical activity of the heart are poorly characterized. The miRNAs miR-1 and miR-133a are the most abundant miRNAs of the heart and are expressed from two miR-1/133a genomic clusters. Genetic modulation of miR-1/133a cluster expression without concomitant severe disturbance of general cardiomyocyte physiology revealed that these miRNA clusters govern cardiac muscle repolarization. Reduction of miR-1/133a dosage induced a longQT phenotype in mice especially at low heart rates. Longer action potentials in cardiomyocytes are caused by modulation of the impact of β-adrenergic signaling on the activity of the depolarizing L-type calcium channel. Pharmacological intervention to attenuate β-adrenergic signaling or L-type calcium channel activity in vivo abrogated the longQT phenotype that is caused by modulation of miR-1/133a activity. Thus, we identify the miR-1/133a miRNA clusters to be important to prevent a longQT-phenotype in the mammalian heart.

  3. Molecular/genetic determinants of repolarization and their modification by environmental stress.

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    Rosen, M R; Cohen, I S

    2006-01-01

    Although a variety of factors, inherited or environmental, can influence expression of ion channel proteins to impact on repolarization, that environment can affect genetic determinants of repolarization for intervals of varying duration is a concept that is not as generally appreciated as it should be. In the following pages we review the molecular/genetic determinants of cardiac repolarization and summarize how pathologic events and environmental intrusions can affect these determinants. Understanding the chains of events involved should yield insights into both the causes and potential avenues of treatment for abnormalities of repolarization.

  4. Supratherapeutic dose evaluation and effect of lesinurad on cardiac repolarization: a thorough QT/QTc study

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    Shen Z

    2016-10-01

    Full Text Available Zancong Shen,1 Michael Gillen,2 Kathy Tieu,1 Mai Nguyen,1 Erin Harmon,1 David M Wilson,1 Bradley Kerr,1 Caroline A Lee1 1Ardea Biosciences, Inc., San Diego, CA, 2AstraZeneca LP, Gaithersburg, MD, USA Introduction: Lesinurad is a selective uric acid reabsorption inhibitor approved in the United States and Europe for treatment of gout in combination with a xanthine oxidase inhibitor. A maximum tolerated dose study was conducted to determine the lesinurad supratherapeutic dose, followed by a thorough QTc study to characterize the effect of lesinurad on cardiac repolarization.Methods: The maximum tolerated dose study was a randomized, double-blind, placebo-controlled, single-ascending dose study that enrolled 35 healthy men and women. Lesinurad plasma exposure (maximum observed plasma concentration and area under the plasma concentration versus time curve was determined at doses of 800 mg, 1,200 mg, and 1,600 mg. The thorough QTc study was a double-blind, four-period, placebo-controlled crossover study with 54 healthy men and women who received single doses of lesinurad 1,600 mg (supratherapeutic dose, lesinurad 400 mg, moxifloxacin 400 mg, and placebo in randomized sequence. Digital 12-lead electrocardiograms were recorded at eleven time points over 24 hours in each treatment period. QT intervals were corrected for heart rate using an individual-specific correction factor (QTcI.Results: The upper bound of the one-sided 95% confidence interval for time-matched, placebo-subtracted, baseline-adjusted QTcI intervals (ΔΔQTcI was <10 ms for both the lesinurad 400 mg and 1,600 mg doses. ΔΔQTcI was independent of lesinurad concentrations. No QTcI thresholds >480 ms or QTcI increases >30 ms were observed. Moxifloxacin mean QTcI intervals were >5 ms, and the lower bounds of the 90% confidence interval were >5 ms at 2 hours, 3 hours, and 4 hours, confirming assay sensitivity.Conclusion: Lesinurad, at supratherapeutic doses, does not

  5. Early repolarization with horizontal ST segment may be associated with aborted sudden cardiac arrest: a retrospective case control study

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    Kim Sung

    2012-12-01

    Full Text Available Abstract Background Risk stratification of the early repolarization pattern (ERP is needed to identify malignant early repolarization. J-point elevation with a horizontal ST segment was recently suggested as a malignant feature of the ERP. In this study, the prevalence of the ERP with a horizontal ST segment was examined among survivors of sudden cardiac arrest (SCA without structural heart disease to evaluate the value of ST-segment morphology in risk stratification of the ERP. Methods We reviewed the data of 83 survivors of SCA who were admitted from August 2005 to August 2010. Among them, 25 subjects without structural heart disease were included. The control group comprised 60 healthy subjects who visited our health promotion center; all control subjects were matched for age, sex, and underlying disease (diabetes mellitus, hypertension. Early repolarization was defined as an elevation of the J point of at least 0.1 mV above the baseline in at least two continuous inferior or lateral leads that manifested as QRS slurring or notching. An ST-segment pattern of Results The SCA group included 17 men (64% with a mean age of 49.7 ± 14.5 years. The corrected QTc was not significantly different between the SCA and control groups (432.7 ± 37.96 vs. 420.4 ± 26.3, respectively; p = 0.089. The prevalence of ERP was not statistically different between the SCA and control groups (5/25, 20% vs. 4/60, 6.7%, respectively; p = 0.116. The prevalence of early repolarization with a horizontal ST segment was more frequent in the SCA than in the control group (20% vs. 3.3%, respectively; p = 0.021. Four SCA subjects (16% and one control subject (1.7% had a J-point elevation of >2 mm (p = 0.025. Four SCA subjects (16% and one (1.7% control subject had an ERP in the inferior lead (p = 0.025. Conclusion The prevalence of ERP with a horizontal ST segment was higher in patients with aborted SCA than in matched controls. This result suggests that ST morphology has

  6. ECG phenomena: pseudopreexcitation and repolarization disturbances resembling ST-elevation myocardial infarction caused by an intraatrial rhabdomyoma in a newborn.

    Science.gov (United States)

    Paech, Christian; Gebauer, Roman Antonin

    2014-01-01

    As is known from other reports, a rhabdomyoma or tumor metastasis may alter intracardiac electrical conduction, producing electrical phenomena like pseudopreexcitation or repolarization disturbances resembling ST-elevation myocardial infarction or Brugada's syndrome. We present a newborn with a giant atrial rhabdomyoma and additionally multiple ventricular rhabdomyomas. He presented with several electrocardiogram (ECG) phenomena due to tumor-caused atrial depolarization and repolarization disturbances. Except from the cardiac tumors, the physical status was within normal range. Initial ECG showed a rapid atrial tachycardia with a ventricular rate of 230 bpm, which was terminated by electrical cardioversion. Afterwards, the ECG showed atrial rhythm with frequent atrial premature contractions and deformation of the PR interval with large, broad P waves and loss of discret PR segment, imposing as pseudopreexcitation. The following QRS complex was normal, with seemingly abnormal ventricular repolarization resembeling ST-elevation myocardial infarction. The atrial tumor was resected with consequent vast atrial reconstruction using patch plastic. The ventricular tumors were left without manipulation. After surgery, pseudopreexcitation and repolarization abnormalities vanished entirely and an alternans between sinus rhythm and ectopic atrial rhythm was present. These phenomena were supposably caused by isolated atrial depolarization disturbances due to tumor-caused heterogenous endocardial activation. The seemingly abnormal ventricular repolarization is probably due to repolarization of the atrial mass, superimposed on the ventricular repolarization. Recognizably, the QRS complex before and after surgical resection of the rhabdomyoma is identical, underlining the atrial origin of the repolarization abnormalities before surgery.

  7. Cardiac Arrhythmias and Abnormal Electrocardiograms After Acute Stroke.

    Science.gov (United States)

    Ruthirago, Doungporn; Julayanont, Parunyou; Tantrachoti, Pakpoom; Kim, Jongyeol; Nugent, Kenneth

    2016-01-01

    Cardiac arrhythmias and electrocardiogram (ECG) abnormalities occur frequently but are often underrecognized after strokes. Acute ischemic and hemorrhagic strokes in some particular area of brain can disrupt central autonomic control of the heart, precipitating cardiac arrhythmias, ECG abnormalities, myocardial injury and sometimes sudden death. Identification of high-risk patients after acute stroke is important to arrange appropriate cardiac monitoring and effective management of arrhythmias, and to prevent cardiac morbidity and mortality. More studies are needed to better clarify pathogenesis, localization of areas associated with arrhythmias and practical management of arrhythmias and abnormal ECGs after acute stroke.

  8. Repolarization reserve, arrhythmia and new drug development

    Directory of Open Access Journals (Sweden)

    Yang Li

    2013-05-01

    Full Text Available Repolarization-related lethal arrhythmias have led to the concept of “repolarization reserve”, which may help elucidate the relationship between K+ currents and other components of repolarization. Pharmacological manipulation as well as congenital and cardiac disease may affect repolarization and alter the repolarization reserve, leading to the development of arrhythmias. Pharmacological enhancement of outward currents or suppression of inward currents has been shown to be of therapeutic value. A number of newly found selective ion channel inhibitors or agonists have been investigated for their ability to enhance repolarization reserve and decrease the incidence of arrhythmia. In this paper we review the development, potential mechanisms, clinical application, and pharmacological significance of repolarization reserve in order to better understand, predict and prevent unexplained adverse cardiac events.

  9. A Retrospective Study of Congenital Cardiac Abnormality Associated with Scoliosis

    Science.gov (United States)

    Ucpunar, Hanifi; Sevencan, Ahmet; Balioglu, Mehmet Bulent; Albayrak, Akif; Polat, Veli

    2016-01-01

    Study Design Retrospective study. Purpose To identify the incidence of congenital cardiac abnormalities in patients who had scoliosis and underwent surgical treatment for scoliosis. Overview of Literature Congenital and idiopathic scoliosis (IS) are associated with cardiac abnormalities. We sought to establish and compare the incidence of congenital cardiac abnormalities in patients with idiopathic and congenital scoliosis (CS) who underwent surgical treatment for scoliosis. Methods Ninety consecutive scoliosis patients, who underwent surgical correction of scoliosis, were classified as CS (55 patients, 28 female [51%]) and IS (35 patients, 21 female [60%]). The complete data of the patients, including medical records, plain radiograph and transthoracic echocardiography were retrospectively assessed. Results We found that mitral valve prolapse was the most common cardiac abnormality in both patients with IS (nine patients, 26%) and CS (13 patients, 24%). Other congenital cardiac abnormalities were atrial septal aneurysm (23% of IS patients, 18% of CS patients), pulmonary insufficiency (20% of IS patients, 4% of CS patients), aortic insufficiency (17% of IS patients), atrial septal defect (11% of IS patients, 13% of CS patients), patent foramen ovale (15% of CS patients), dextrocardia (4% of CS patients), bicuspid aortic valve (3% of IS patients), aortic stenosis (2% of CS patients), ventricular septal defect (2% of CS patients), and cardiomyopathy (2% of CS patients). Conclusions We determined the increased incidence of congenital cardiac abnormalities among patients with congenital and IS. Mitral valve prolapse appeared to be the most prevalent congenital cardiac abnormality in both groups. PMID:27114761

  10. Brugada syndrome and right ventricle morphofunctional abnormalities on echocardiography in young male with family anamnesis of sudden cardiac death.

    Science.gov (United States)

    Steiner, Robert; Makarovic, Sandra; Makarovic, Zorin; Bilic-Curcic, Ines

    2014-03-01

    First presented by Brugada and Brugada in 1992, Brugada Syndrome (BrS) is a primary electrical disease of the heart that causes sudden cardiac death or life-threatening ventricular arrhythmias. This disease is hereditary autosomic dominant transmitted and genetically determined. The syndrome has been linked to mutations in SCN5A, the gene encoding for the a-subunit of the sodium channel. Electrocardiogram (ECG) abnormalities indicating Brugada syndrome, include repolarization and depolarization abnormalities in the absence of identifiable structural cardiac abnormalities or other conditions or agents known to lead to ST-segment elevation in the right precordial leads (V1-V3). Intravenous administration of sodium channel blocking drugs may modify the ECG pattern. Ajmaline, flecainide, procainamide and propafenone exaggerate the ST-segment elevation or unmask it when it is initially absent. An implantable cardioverter-defibrillator (ICD) is the only proven effective device treatment for the disease. Although BrS is primary electrical disease, some authors have suggested the presence of morphological and functional abnormalities mainly located in the right ventricle (RV), notably in the outflow tract (RVOT). In this short report we will present a young male, with predisposition and positive family history of sudden cardiac death, with complete diagnostic procedure including propafenon testing unmasking Brugada syndrome. An echosonography revealed dilated apical right ventricle, suggesting BrS is not only electrical disorder, but may include morphofunctional abnormalities, described in previous reports. In addition, we reviewed the possible connection between Brugada syndrome and morphological abnormalities in RV.

  11. Quinidine elicits proarrhythmic changes in ventricular repolarization and refractoriness in guinea-pig.

    Science.gov (United States)

    Osadchii, Oleg E

    2013-04-01

    Quinidine is a class Ia Na(+) channel blocker that prolongs cardiac repolarization owing to the inhibition of I(Kr), the rapid component of the delayed rectifier current. Although quinidine may induce proarrhythmia, the contributing mechanisms remain incompletely understood. This study examined whether quinidine may set proarrhythmic substrate by inducing spatiotemporal abnormalities in repolarization and refractoriness. The monophasic action potential duration (APD), effective refractory periods (ERPs), and volume-conducted electrocardiograms (ECGs) were assessed in perfused guinea-pig hearts. Quinidine was found to produce the reverse rate-dependent prolongation of ventricular repolarization, which contributed to increased steepness of APD restitution. Throughout the epicardium, quinidine elicited a greater APD increase in the left ventricular chamber compared with the right ventricle, thereby enhancing spatial repolarization heterogeneities. Quinidine prolonged APD to a greater extent than ERP, thus extending the vulnerable window for ventricular re-excitation. This change was attributed to increased triangulation of epicardial action potential because of greater APD lengthening at 90% repolarization than at 30% repolarization. Over the transmural plane, quinidine evoked a greater ERP prolongation at endocardium than epicardium and increased dispersion of refractoriness. Premature ectopic beats and monomorphic ventricular tachycardia were observed in 50% of quinidine-treated heart preparations. In summary, abnormal changes in repolarization and refractoriness contribute greatly to proarrhythmic substrate upon quinidine infusion.

  12. Comparison of electrophysiological effects of calcium channel blockers on cardiac repolarization.

    Science.gov (United States)

    Lee, Hyang-Ae; Hyun, Sung-Ae; Park, Sung-Gurl; Kim, Ki-Suk; Kim, Sung Joon

    2016-01-01

    Dihydropyridine (DHP) calcium channel blockers (CCBs) have been widely used to treat of several cardiovascular diseases. An excessive shortening of action potential duration (APD) due to the reduction of Ca(2+) channel current (I Ca) might increase the risk of arrhythmia. In this study we investigated the electrophysiological effects of nicardipine (NIC), isradipine (ISR), and amlodipine (AML) on the cardiac APD in rabbit Purkinje fibers, voltage-gated K(+) channel currents (I Kr, I Ks) and voltage-gated Na(+) channel current (I Na). The concentration-dependent inhibition of Ca(2+) channel currents (I Ca) was examined in rat cardiomyocytes; these CCBs have similar potency on I Ca channel blocking with IC50 (the half-maximum inhibiting concentration) values of 0.142, 0.229, and 0.227 nM on NIC, ISR, and AML, respectively. However, ISR shortened both APD50 and APD90 already at 1 µM whereas NIC and AML shortened APD50 but not APD90 up to 30 µM. According to ion channel studies, NIC and AML concentration-dependently inhibited I Kr and I Ks while ISR had only partial inhibitory effects (NIC and AML could compensate for the AP shortening effects due to the block of I Ca.

  13. Postoperative cardiac arrest in children with congenital heart abnormalities

    OpenAIRE

    2013-01-01

    BACKGROUND The exact survival rates and markers of survival after postoperative cardiac arrest in children with congenital heart abnormalities are unknown. METHODS In this one-year study, we identified children younger than seven years of age with postoperative cardiac arrest in our pediatric cardiac intensive care unit database. Parameters from perioperative, pre-arrest, and resuscitation periods were analyzed for these patients. Comparisons were made between survivors and non-survivors afte...

  14. Cardiac hypertrophy in hypertension. Repolarization abnormalities elicited by rapid lowering of pressure.

    Science.gov (United States)

    Pepi, M; Alimento, M; Maltagliati, A; Guazzi, M D

    1988-01-01

    In hypertension, coronary flow is augmented and oxygen balance is adequate despite an increase in coronary resistance. For the maintenance of flow in the presence of and after regression of ventricular hypertrophy, the ratio of pressure and ventricular mass must remain normal. Coronary reserve would be altered if treatment normalized pressure but not ventricular mass or if pressure were lowered too fast. We investigated 42 patients with primary hypertension. In 28 (Group I) left ventricular mass index (by ultrasound) was within the mean value +2 SD (96 + 38 g/m2) of 145 controls and exceeded these values in the remaining 14 patients (Group 2). The diastolic pressure was lowered rapidly to between 85 and 90 mm Hg with two potent vasodilators, nifedipine (sublingually) and nitroprusside, while a 12-lead electrocardiogram was recorded continuously. During both tests, seven patients in Group 2 (responders) showed inversion of normal T waves, in lead I, aVL, and V3-6. These changes waxed and waned in parallel with the pressure fall and recovery and were not attributable to alterations in adrenergic tone, conduction disturbances, variations, or group differences in the QRS axis, QTc interval, heart rate, left ventricular fractional shortening, wall stress, rate of dimension increase in early diastole, or isovolumic relaxation. A "steal phenomenon'' or passive collapse in compliant coronary lesions during vasodilatation seems unlikely; in fact, patients were free from coronary symptoms, and the electrocardiographic alterations occurred only in seven patients in Group 2, who had a greater left ventricular mass index and required a larger pressure drop to return the diastolic pressure to normal.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Cardiac abnormalities in children with hyperthyroidism.

    Science.gov (United States)

    Lester, L A; Sodt, P C; Rich, B H; Lucky, A W; Hutcheon, N; Arcilla, R A

    1982-01-01

    The cardiac status of 18 hyperthyroid (HT) children (9 black and 9 white) was evaluated by echocardiography. Mitral regurgitation (MR) was diagnosed clinically in 33% (6 of the 9 blacks). None of the 9 white children had MR. Left ventricular end-diastolic diameter (LVEDD) and volume (LVEDV) did not differ from the predicted normal (PN) based on body surface area and heart rate, except in those with MR where increased LVEDD and LVEDV were noted (p less than 0.02). LV mass was +1.75 standard deviations (sigma) of the PN (p less than 0.01), due to increased wall thickness of LVEDV. Left ventricular output (LVO) was +0.35 sigma PN (p = ns); however, when compared to that of normal children, LVO of HT was higher (p less than 0.001) due to the increased heart rate. Enhanced left ventricular contractility was suggested by increased rate of dimensional change during ejection (peak dD/dt-syst), with a mean value of -11.39 cm/sec as compared to the normal of -9.54 cm/sec (p less than 0.01). A linear multivariate regression equation differentiated the cardiac status of HT from that of normal children. Following treatment to euthyroid state, MR disappeared in 2 and became less in 4 patients. LVO, LV mass, and peak dD/dt-syst also became less. Significant cardiac changes occur in children with hyperthyroidism, which may be reversible in part after euthyroidism is restored.

  16. Effects of acute intravenous administration of pentamidine, a typical hERG-trafficking inhibitor, on the cardiac repolarization process of halothane-anesthetized dogs.

    Science.gov (United States)

    Yokoyama, Hirofumi; Nakamura, Yuji; Iwasaki, Hiroshi; Nagayama, Yukitoshi; Hoshiai, Kiyotaka; Mitsumori, Yoshitaka; Sugiyama, Atsushi

    2009-08-01

    Although acute treatment of pentamidine does not directly modify any ionic channel function in the heart at clinically relevant concentrations, its continuous exposure can prolong QT interval. Recent in vitro studies have indicated that hERG trafficking inhibition may play an important role in the onset of pentamidine-induced long QT syndrome. In this study, we examined acute in vivo electropharmacological effects of pentamidine using the halothane-anesthetized canine model (n = 5). The clinically relevant total dose of 4 mg/kg of pentamidine (namely, 1 mg/kg, i.v. over 10 min followed by 3 mg/kg, i.v. over 10 min with a pause of 20 min) decreased the mean blood pressure, ventricular contraction, preload to the left ventricle, and peripheral vascular resistance. Pentamidine also enhanced the atrioventricular conduction in parallel with its cardiohemodynamic actions, but it gradually prolonged both the ventricular repolarization period and effective refractory period, whereas no significant change was detected in the intraventricular conduction. Thus, acute administration of a clinically relevant dose of pentamidine can suppress cardiac function and vascular tone with reflex-mediated increase of sympathetic activity, whereas it may delay the repolarization process, suggesting that inhibition of potassium-channel trafficking might be induced more acutely in vivo than those previously expected in vitro.

  17. Resolution of abnormal cardiac MRI T2 signal following immune suppression for cardiac sarcoidosis.

    Science.gov (United States)

    Crouser, Elliott D; Ruden, Emily; Julian, Mark W; Raman, Subha V

    2016-08-01

    Cardiac MR (CMR) with late gadolinium enhancement is commonly used to detect cardiac damage in the setting of cardiac sarcoidosis. The addition of T2 mapping to CMR was recently shown to enhance cardiac sarcoidosis detection and correlates with increased cardiac arrhythmia risk. This study was conducted to determine if CMR T2 abnormalities and related arrhythmias are reversible following immune suppression therapy. A retrospective study of subjects with cardiac sarcoidosis with abnormal T2 signal on baseline CMR and a follow-up CMR study at least 4 months later was conducted at The Ohio State University from 2011 to 2015. Immune suppression treated participants had a significant reduction in peak myocardial T2 value (70.0±5.5 vs 59.2±6.1 ms, pretreatment vs post-treatment; p=0.017), and 83% of immune suppression treated subjects had objective improvement in cardiac arrhythmias. Two subjects who had received inadequate immune suppression treatment experienced progression of cardiac sarcoidosis. This report indicates that abnormal CMR T2 signal represents an acute inflammatory manifestation of cardiac sarcoidosis that is potentially reversible with adequate immune suppression therapy.

  18. Cardiac abnormalities in children with sickle cell anemia.

    Science.gov (United States)

    Lester, L A; Sodt, P C; Hutcheon, N; Arcilla, R A

    1990-11-01

    The cardiac status of 64 children (ages 0.2 to 18 yr) with sickle cell anemia documented by hemoglobin electrophoresis was evaluated by echocardiography. Left atrial, left ventricular and aortic root dimensions were significantly increased in over 60 percent of these children at all ages compared to values for 99 normal black (non-SCA) control subjects. Left ventricular wall thickness was increased in only 20 percent of older children with sickle cell anemia. Estimated LV mass/m2 and left ventricular cardiac index were increased compared to control subjects (p less than 0.001). Left heart abnormalities expressed as a single composite function, derived from multivariate regression analysis, correlated well with severity of anemia expressed as grams of hemoglobin (r = -0.52, p = less than 0.001) and with percentage of hemoglobin S (r = 0.51, p less than 0.001), but not to the same extent with age. Echocardiographically assessed left ventricular function at rest was comparable to that of control subjects. These data suggest that the major cardiac abnormalities in children are related to the volume overload effects of chronic anemia, and that in this age group, there is no evidence for a distinct "sickle cell cardiomyopathy" or cardiac dysfunction.

  19. Prevalence of cardiac dysfunction and abnormalities in patients with adolescent idiopathic scoliosis requiring surgery.

    Science.gov (United States)

    Liu, Limin; Xiu, Peng; Li, Qian; Song, Yueming; Chen, Rigao; Zhou, Chunguang

    2010-12-01

    The prevalence of cardiac abnormalities in patients with adolescent idiopathic scoliosis in an Asian population has not been reported. A retrospective study was conducted to evaluate the incidence of cardiac abnormalities in these patients. From January 2007 to April 2009, echocardiography and pulmonary function tests were performed in 80 adolescent idiopathic scoliosis patients who required surgical intervention. A thorough analysis of cardiopulmonary functions and cardiac structures was performed. The risk factors, types of cardiac abnormalities, and associations between severity of scoliosis or pulmonary function and cardiac abnormalities were assessed. Cardiac abnormalities were detected by echocardiogram in 25 patients, including 14 with structural abnormalities and 11 with functional abnormalities. The most common functional abnormality was tricuspid regurgitation (9 of 80; 11.3%), whereas atrial septal defect was the most common structural abnormality (7 of 80). Altered hemodynamics occurred in 5 patients, including 3 with ventricular septal defect and 2 with mitral valve dysplasia. Abnormal electrocardiographic findings presented in only 9 of the 25 patients with cardiac abnormalities. No significant associations were found between severity of scoliosis or pulmonary function and cardiac abnormalities. A high incidence of cardiac abnormality exists in patients with adolescent idiopathic scoliosis in this region. Although most patients tolerated surgery, some patients were at risk of decompensation postoperatively. Electrocardiography is of limited value for detecting cardiac problems in patients with adolescent idiopathic scoliosis, we recommend echocardiography as a routine modality in the preoperative evaluation of patients with adolescent idiopathic scoliosis.

  20. Cardiac abnormalities discovered during long-term monitoring for epilepsy.

    Science.gov (United States)

    Herder, Lisa A

    2008-09-01

    During routine EEGs, ambulatory EEGs, prolonged EEGs in the intensive care unit, and long-term monitoring for epilepsy (LTME), trained technologists record cerebral activity as well as a basic electrocardiogram (ECG). The traditional use of this ECG tracing is to differentiate ECG artifact from abnormal brain activity. The past few years of LTME have given rise to a greater appreciation of the importance of ECG recording in patients undergoing continuous video EEG monitoring. The ECG must be reviewed for abnormalities, both ictal and non-ictal related. Although EEG technologists are not formally trained in ECG, abnormalities on ECG may be observed that could warrant further investigation through cardiology services. In addition to treating the patient's neurological issues, it may be possible to bring attention to previously undiagnosed cardiac problems that could seriously threaten the patient's health.

  1. Cardiac abnormalities in acromegaly. Pathophysiology and implications for management.

    Science.gov (United States)

    Vitale, Giovanni; Pivonello, Rosario; Lombardi, Gaetano; Colao, Annamaria

    2004-01-01

    Cardiovascular disease is claimed to be one of the most severe complications of acromegaly, contributing significantly to mortality in this disease. In fact, an excess of growth hormone (GH) and insulin-like growth factor 1 (IGF-I) causes a specific derangement of cardiomyocytes, leading to abnormalities in cardiac muscle structure and function, inducing a specific cardiomyopathy. In the early phase of acromegaly the excess of GH and IGF-I induces a hyperkinetic syndrome, characterized by increased heart rate and increased systolic output. Concentric hypertrophy is the most common feature of cardiac involvement in acromegaly, found in more than two thirds of patients at diagnosis. This abnormality is commonly associated with diastolic dysfunction and eventually with impaired systolic function ending in heart failure, if the GH/IGF-I excess is left untreated. In addition, abnormalities of cardiac rhythm and of heart valves have also been described in acromegaly. The coexistence of other complications, such as arterial hypertension and diabetes mellitus, aggravates acromegalic cardiomyopathy. Successful control of acromegaly induces a decrease in left ventricular mass and an improvement in diastolic function, while the effects of GH/IGF-I suppression on systolic function are more variable. However, since cardiovascular alterations in young patients with short disease duration are milder than in those with longer disease duration, it is likely to be easier to reverse and/or arrest acromegalic cardiomyopathy in young patients with early-onset disease. In conclusion, careful assessments of cardiac function, morphology, and activity are required in patients with acromegaly. An early diagnosis and prompt effective treatment are important in order to reverse acromegalic cardiomyopathy.

  2. Update on the evaluation of a new drug for effects on cardiac repolarization in humans: issues in early drug development

    OpenAIRE

    Salvi, Vaibhav; Karnad, Dilip R.; Panicker, Gopi Krishna; Kothari, Snehal

    2009-01-01

    Following reports of death from cardiac arrhythmias with drugs like terfenadine and cisapride, the International Conference for Harmonization formulated a guidance (E14) document. This specifies that all new drugs must undergo a ‘thorough QT/QTc’ (TQT) study to detect drug-induced QT prolongation, a surrogate marker of ventricular tachycardia, especially torsades de pointes (TdPs). With better understanding of data from several completed TQT studies, regulatory requirements have undergone som...

  3. Ventricular repolarization measures for arrhythmic risk stratification

    Institute of Scientific and Technical Information of China (English)

    Francesco Monitillo; Marta Leone; Caterina Rizzo; Andrea Passantino; Massimo Iacoviello

    2016-01-01

    Ventricular repolarization is a complex electrical phenomenon which represents a crucial stage in electrical cardiac activity. It is expressed on the surface electrocardiogram by the interval between the start of the QRS complex and the end of the T wave or U wave(QT). Several physiological, pathological and iatrogenic factors can influence ventricular repolarization. It has been demonstrated that small perturbations in this process can be a potential trigger of malignant arrhythmias, therefore the analysis of ventricular repolarization represents an interesting tool to implement risk stratification of arrhythmic events in different clinical settings. The aim of this review is to critically revise the traditional methods of static analysis of ventricular repolarization as well as those for dynamic evaluation, their prognostic significance and the possible application in daily clinical practice.

  4. Early Repolarization Syndrome

    Directory of Open Access Journals (Sweden)

    Frederic Sacher

    2015-04-01

    Full Text Available The electrocardiographic pattern of early repolarization (ER is common, with a particularly high prevalence reported amongst athletes and adolescents. It has long been associated with benign outcome [1-3]. Recently, an association between inferolateral ER pattern and sudden cardiac death (SCD has been established by different groups [4-7]. Population-based studies have also reported an increased mortality rate among patients with inferolateral ER pattern compared to controls [7-9]. To bring back together these differences, it is important to focus on the definition of ER pattern used in these different studies as well as the population included. The definition of ER pattern associated with sudden cardiac death was the presence of J point elevation more than or equal to 0.1mV in at least 2 contiguous inferior and/or lateral leads of a standard 12-lead ECG and not ST elevation as it was often the case in the studies with benign outcome. Any study dealing with ER should clearly indicate the definition used. Otherwise it cannot be interpreted. Talking about definition, ER syndrome is an ER pattern (as defined above associated with symptoms (syncope or aborted SCD and/or familial history of SCD as mentioned in the last HRS/EHRA/APHRS Expert Consensus Statement on the Diagnosis and Management of Patients with Inherited Primary Arrhythmia Syndromes [10]. It is important to recognise that having only an ER pattern is not a disease.

  5. [Parameters of cardiac muscle repolarization on the electrocardiogram when changing anatomical and electric position of the heart].

    Science.gov (United States)

    Chaĭkovskiĭ, I A; Baum, O V; Popov, L A; Voloshin, V I; Budnik, N N; Frolov, Iu A; Kovalenko, A S

    2014-01-01

    While discussing the diagnostic value of the single channel electrocardiogram a set of theoretical considerations emerges inevitably, one of the most important among them is the question about dependence of the electrocardiogram parameters from the direction of electrical axis of heart. In other words, changes in what of electrocardiogram parameters are in fact liable to reflect pathological processes in myocardium, and what ones are determined by extracardiac factors, primarily by anatomic characteristics of patients. It is arguable that while analyzing electrocardiogram it is necessary to orient to such physiologically based informative indexes as ST segment displacement. Also, symmetry of the T wave shape is an important parameter which is independent of patients anatomic features. The results obtained are of interest for theoretical and applied aspects of the biophysics of the cardiac electric field.

  6. Cardiac abnormalities assessed by non-invasive techniques in patients with newly diagnosed idiopathic inflammatory myopathies

    DEFF Research Database (Denmark)

    Diederichsen, Louise Pyndt; Simonsen, Jane Angel; Diederichsen, Axel Cosmus Pyndt;

    2015-01-01

    , cardiac troponin-I (TnI), electrocardiogram (standard 12-lead and 48-h Holter monitoring), echocardiography with tissue Doppler measures, cardiac magnetic resonance (CMR) imaging with T2 mapping and semi-quantitative (99m)technetium pyrophosphate ((99m)Tc-PYP) scintigraphy. RESULTS: Dyspnoea was present....... The myocardial (99m)Tc-PYP uptake and CMR results differed between patients and controls, albeit not with statistical significance. Overall, cardiac abnormalities were demonstrated in 9 (64%) of the patients versus 2 (14%) of the controls (p=0.02). CONCLUSIONS: Cardiac abnormalities assessed by TnI, ECG...

  7. Abnormal cardiac enzymes in systemic sclerosis: a report of four patients and review of the literature.

    Science.gov (United States)

    Vasta, B; Flower, V; Bucciarelli-Ducci, C; Brown, S; Korendowych, E; McHugh, N J; Pauling, J D

    2014-03-01

    Cardiac involvement in systemic sclerosis (SSc) is heterogeneous and can include primary involvement of the myocardium, pericardium and coronary arteries or be secondary to cardiac complications of pulmonary and renal disease. Primary cardiac involvement in SSc is uncommon but can result in ventricular dysfunction, organ failure, arrhythmias and death. It can remain clinically silent and the prevalence is likely to be under-reported. We report four cases of SSc associated with a raised serum troponin T (TnT), in a proportion of whom cardiac MRI myocardial abnormalities were detected. These cases highlight the heterogeneity of cardiac involvement in SSc, the role of cardiac MRI and promising biochemical responses to immunosuppression. Cardiac biomarkers such as TnT may be useful screening tools to identify subclinical cardiac disease and assess response to therapeutic intervention.

  8. Sixty-seven Cases of Abnormal Movement of the Cardiac Apex Treated with Bu Xin Tang

    Institute of Scientific and Technical Information of China (English)

    王平; 耿世钊

    2002-01-01

    @@ Bu Xin Tang (heart-reinforcement decoction) was used to treat 67 cases of abnormal movement of the cardiac apex based on differentiation of symptoms and signs. The results showed that, in most patients, there were remarkable improvement notonly for the symptoms but also for the abnormal movement of the cardiac apex. The cured plus remarkably effective rate was 87%, suggesting that it can postponeor prevent coronary heart attacks for the patient of prophase coronary heart disease.

  9. Cardiac Abnormalities in Adult Patients With Polymyositis or Dermatomyositis as Assessed by Noninvasive Modalities

    DEFF Research Database (Denmark)

    Diederichsen, L P; Simonsen, J A; Diederichsen, A C

    2016-01-01

    OBJECTIVE: Cardiac events are a major cause of death in patients with idiopathic inflammatory myopathies. The study objective was in a controlled setting to describe cardiac abnormalities by noninvasive methods in a cohort of patients with polymyositis (PM) or dermatomyositis (DM) and to identify...

  10. Diurnal modulation and sources of variation affecting ventricular repolarization in Warmblood horses

    DEFF Research Database (Denmark)

    Pedersen, Philip Juul; Moeller, Sine B; Flethøj, Mette;

    2014-01-01

    OBJECTIVES: Irregularities in cardiac repolarization are known to predispose for arrhythmias and sudden cardiac death in humans. The QT interval is a quantitative measurement of repolarization, and clinically, the QTc (QT interval corrected for heart rate) and Tpeak to Tend intervals (TpTe) are u...

  11. Abnormal Cardiac Autonomic Regulation in Mice Lacking ASIC3

    Directory of Open Access Journals (Sweden)

    Ching-Feng Cheng

    2014-01-01

    Full Text Available Integration of sympathetic and parasympathetic outflow is essential in maintaining normal cardiac autonomic function. Recent studies demonstrate that acid-sensing ion channel 3 (ASIC3 is a sensitive acid sensor for cardiac ischemia and prolonged mild acidification can open ASIC3 and evoke a sustained inward current that fires action potentials in cardiac sensory neurons. However, the physiological role of ASIC3 in cardiac autonomic regulation is not known. In this study, we elucidate the role of ASIC3 in cardiac autonomic function using Asic3−/− mice. Asic3−/− mice showed normal baseline heart rate and lower blood pressure as compared with their wild-type littermates. Heart rate variability analyses revealed imbalanced autonomic regulation, with decreased sympathetic function. Furthermore, Asic3−/− mice demonstrated a blunted response to isoproterenol-induced cardiac tachycardia and prolonged duration to recover to baseline heart rate. Moreover, quantitative RT-PCR analysis of gene expression in sensory ganglia and heart revealed that no gene compensation for muscarinic acetylcholines receptors and beta-adrenalin receptors were found in Asic3−/− mice. In summary, we unraveled an important role of ASIC3 in regulating cardiac autonomic function, whereby loss of ASIC3 alters the normal physiological response to ischemic stimuli, which reveals new implications for therapy in autonomic nervous system-related cardiovascular diseases.

  12. Pattern recognition of abnormal left ventricle wall motion in cardiac MR.

    Science.gov (United States)

    Lu, Yingli; Radau, Perry; Connelly, Kim; Dick, Alexander; Wright, Graham

    2009-01-01

    There are four main problems that limit application of pattern recognition techniques for recognition of abnormal cardiac left ventricle (LV) wall motion: (1) Normalization of the LV's size, shape, intensity level and position; (2) defining a spatial correspondence between phases and subjects; (3) extracting features; (4) and discriminating abnormal from normal wall motion. Solving these four problems is required for application of pattern recognition techniques to classify the normal and abnormal LV wall motion. In this work, we introduce a normalization scheme to solve the first and second problems. With this scheme, LVs are normalized to the same position, size, and intensity level. Using the normalized images, we proposed an intra-segment classification criterion based on a correlation measure to solve the third and fourth problems. Application of the method to recognition of abnormal cardiac MR LV wall motion showed promising results.

  13. Delayed ventricular repolarization as an anti-arrhythmic principle.

    Science.gov (United States)

    Vaughan Williams, E M

    1985-11-01

    Depolarization of cardiac muscle is achieved by 'fast inward current' through channels which are inactivated within about 1 ms. When the cells are repolarized the process of inactivation of fast channels is rapidly reversed. The class 1 anti-arrhythmic drugs delay the disappearance of inactivation until long after repolarization is complete. In theory, it should be possible to produce a similar extension of refractory period by delaying the repolarization itself. Quinidine and disopyramide caused minor delays of repolarization, but both were primarily class 1 agents, and in addition had undesirable anticholinergic activity. Amiodarone, already in use for many years as an antianginal drug, prolonged action potential duration (APD) and was shown to have an anti-arrhythmic action in rabbits, dogs and man. Although prolongation of APD lengthens QT, a long QT may be caused by phenomena other than prolonged APD, such as heterogeneity of sympathetic drive. Association of long QT with arrhythmia does not, therefore, invalidate the principle that homogeneously prolonged APD should be anti-arrhythmic. In practice, amiodarone, bretylium, sotalol, thyroidectomy, and long-term beta-blockade prolong APD, and are associated with low incidence of arrhythmia. Many mechanisms controlling cardiac repolarization have been proposed, but how repolarization is delayed by individual agents is not fully elucidated.

  14. Cardiac abnormalities in a follow-up study on carriers of Duchenne and Becker muscular dystrophy

    NARCIS (Netherlands)

    van Westrum, S. M. Schade; Hoogerwaard, E. M.; Dekker, L.; Standaar, T. S.; Bakker, E.; Ippel, P. F.; Oosterwijk, J. C.; Majoor-Krakauer, D. F.; van Essen, A. J.; Leschot, N. J.; Wilde, A. A. M.; de Haan, R. J.; de Visser, M.; van der Kooi, A. J.

    2011-01-01

    Objectives: Cardiac involvement has been reported in carriers of dystrophin mutations giving rise to Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD). The progress of these abnormalities during long-term follow-up is unknown. We describe the long-term follow-up of dilated cardio

  15. Cardiac defects, nuchal edema and abnormal lymphatic development are not associated with morphological changes in the ductus venosus

    NARCIS (Netherlands)

    Burger, Nicole B.; Haak, Monique C.; Kok, Evelien; de Groot, Christianne J M; Shou, Weinian; Scambler, Peter J.; Lee, Youngsook; Cho, Eunjin; Christoffels, Vincent M.; Bekker, Mireille N.

    2016-01-01

    Background In human fetuses with cardiac defects and increased nuchal translucency, abnormal ductus venosus flow velocity waveforms are observed. It is unknown whether abnormal ductus venosus flow velocity waveforms in fetuses with increased nuchal translucency are a reflection of altered cardiac fu

  16. Detection of Cardiac Abnormalities from Multilead ECG using Multiscale Phase Alternation Features.

    Science.gov (United States)

    Tripathy, R K; Dandapat, S

    2016-06-01

    The cardiac activities such as the depolarization and the relaxation of atria and ventricles are observed in electrocardiogram (ECG). The changes in the morphological features of ECG are the symptoms of particular heart pathology. It is a cumbersome task for medical experts to visually identify any subtle changes in the morphological features during 24 hours of ECG recording. Therefore, the automated analysis of ECG signal is a need for accurate detection of cardiac abnormalities. In this paper, a novel method for automated detection of cardiac abnormalities from multilead ECG is proposed. The method uses multiscale phase alternation (PA) features of multilead ECG and two classifiers, k-nearest neighbor (KNN) and fuzzy KNN for classification of bundle branch block (BBB), myocardial infarction (MI), heart muscle defect (HMD) and healthy control (HC). The dual tree complex wavelet transform (DTCWT) is used to decompose the ECG signal of each lead into complex wavelet coefficients at different scales. The phase of the complex wavelet coefficients is computed and the PA values at each wavelet scale are used as features for detection and classification of cardiac abnormalities. A publicly available multilead ECG database (PTB database) is used for testing of the proposed method. The experimental results show that, the proposed multiscale PA features and the fuzzy KNN classifier have better performance for detection of cardiac abnormalities with sensitivity values of 78.12 %, 80.90 % and 94.31 % for BBB, HMD and MI classes. The sensitivity value of proposed method for MI class is compared with the state-of-art techniques from multilead ECG.

  17. The Association between Myocardial Iron Load and Ventricular Repolarization Parameters in Asymptomatic Beta-Thalassemia Patients

    Directory of Open Access Journals (Sweden)

    Mehmet Kayrak

    2012-01-01

    Full Text Available Previous studies have demonstrated impaired ventricular repolarization in patients with β-TM. However, the effect of iron overload with cardiac T2* magnetic resonance imaging (MRI on cardiac repolarization remains unclear yet. We aimed to examine relationship between repolarization parameters and iron loading using cardiac T2* MRI in asymptomatic β-TM patients. Twenty-two β-TM patients and 22 age- and gender-matched healthy controls were enrolled to the study. From the 12-lead surface electrocardiography, regional and transmyocardial repolarization parameters were evaluated manually by two experienced cardiologists. All patients were also undergone MRI for cardiac T2* evaluation. Cardiac T2* score <20 msec was considered as iron overload status. Of the QT parameters, QT duration, corrected QT interval, and QT peak duration were significantly longer in the β-TM group compared to the healthy controls. Tp−Te and Tp−Te dispersions were also significantly prolonged in β-TM group compared to healthy controls. (Tp-Te/QT was similar between groups. There was no correlation between repolarization parameters and cardiac T2* MRI values. In conclusion, although repolarization parameters were prolonged in asymptomatic β-TM patients compared with control, we could not find any relation between ECG findings and cardiac iron load.

  18. Coronary artery calcification is associated with atherogenic lipid changes, cardiac dysfunction and morphologic abnormalities in HIV-1 infected black adults

    Institute of Scientific and Technical Information of China (English)

    MENG Qing-yi; DU Jie-fu; LAI Hong; LAI Sheng-han

    2005-01-01

    @@ The heart is an organ frequently affected in the acquired immunodeficiency syndrome.1 But there is little information as to whether the coronary artery calcification can identify asymptomatic individuals at high risk for having cardiac morphological and functional abnormalities and cardiac risk factors in human immunodeficiency virus (HIV)-infected persons. Accordingly, the purpose of this study was to determine whether coronary artery calcification was associated with cardiac morphological and functional abnormalities, atherogenic lipid and C-reactive protein (CRP) changes in a black adult population with HIV-1 infection.

  19. Ventricular repolarization in a rat model of global heart failure.

    Science.gov (United States)

    Krandycheva, Valeria; Kharin, Sergey; Strelkova, Marina; Shumikhin, Konstantin; Sobolev, Aleksey; Shmakov, Dmitry

    2013-07-01

    Isoproterenol in high doses induces infarction-like myocardial damage and structural and functional remodelling of the ventricular myocardium. The purpose of the present study was to investigate ventricular repolarization in a rat model of isoproterenol-induced heart failure. Isoproterenol was administered twice to female Wistar rats (170 mg/kg, s.c., 24 h apart). Four weeks after the injections, cardiac output was measured and unipolar epicardial ventricular electrograms were recorded in situ. Activation-recovery intervals were calculated to assess repolarization. Histological examination of the heart ventricles was also performed. Heart failure in rats treated with isoproterenol was indicated by myocardial histopathological damage and reduced cardiac output. In rats with heart failure, the regional differences in activation-recovery interval prolongation over the ventricular epicardium resulted in increasing heterogeneity in the activation-recovery interval distribution and increasing repolarization heterogeneity of the ventricular subepicardium. Myocardial damage and haemodynamic changes in heart failure induced by isoproterenol were accompanied by significant changes in ventricular repolarization, which were not associated with myocardial hypertrophy.

  20. The association between anger-related personality trait and cardiac autonomic response abnormalities in elderly subjects.

    Science.gov (United States)

    Narita, Kosuke; Murata, Tetsuhito; Takahashi, Tetsuya; Hamada, Toshihiko; Kosaka, Hirotaka; Yoshida, Haruyoshi; Wada, Yuji

    2007-09-01

    Cardiac autonomic response abnormality associated with trait anger has been recognized to elevate blood pressure in daily life, leading to atherosclerotic progression and cardiovascular disease. To clarify the relationship between anger-related personality traits and cardiac autonomic response in healthy elderly subjects, 54 volunteers consisting of 30 male (mean age 62.2+/-5.4) and 24 female (mean age 58.4+/-4.6) subjects underwent testing of heart rate variability (HRV) with head-up tilt. For the evaluation of trait anger, we used a questionnaire corresponding to the trait anger score taken from the State and Trait Anger Expression Inventory. Furthermore, we measured carotid intima-medial thickness (IMT) to evaluate atherosclerotic progression in subjects with anger trait. In female subjects, higher trait anger was positively associated with elevated carotid IMT and the suppression of HRV vagal attenuation from the supine to head-up position, and negatively associated with the HRV sympathetic activity in the head-up position and also with the HRV sympathetic response from the supine to head-up position. In male subjects, trait anger was not significantly associated with carotid IMT or any HRV component with or without head-up tilt testing. We conclude that a simple noninvasive measure, short-term HRV with head-up tilt testing, could be a useful method to investigate the association between cardiac autonomic imbalance and increased risk of atherosclerosis associated with trait anger in healthy elderly subjects.

  1. Some theoretical results on the observability of repolarization heterogeneity on surface ECG.

    Science.gov (United States)

    Mainardi, Luca; Sassi, Roberto

    2013-01-01

    Assessing repolarization heterogeneity (RH) from surface ECG recording is an open issue in modern electrocardiography, despite the fact that several indexes measured on the T-wave have been proposed and tested. To understand how RH occurring at myocite level is reflected on T-wave shapes, in this paper we propose a mathematical framework that combines a simple statistical model of cardiac repolarization times with the dominant T-wave formalism. Within this framework we compare different T-wave features such as T-wave amplitude, T-wave amplitude variability or QT intervals and we describe mathematically how they are linked to the spatial and temporal components of repolarization heterogeneity.

  2. Pulmonary function, cholinergic bronchomotor tone, and cardiac autonomic abnormalities in type 2 diabetic patients

    Directory of Open Access Journals (Sweden)

    Melo E.

    2003-01-01

    Full Text Available This prospective study analyzed the involvement of the autonomic nervous system in pulmonary and cardiac function by evaluating cardiovascular reflex and its correlation with pulmonary function abnormalities of type 2 diabetic patients. Diabetic patients (N = 17 and healthy subjects (N = 17 were evaluated by 1 pulmonary function tests including spirometry, He-dilution method, N2 washout test, and specific airway conductance (SGaw determined by plethysmography before and after aerosol administration of atropine sulfate, and 2 autonomic cardiovascular activity by the passive tilting test and the magnitude of respiratory sinus arrhythmia (RSA. Basal heart rate was higher in the diabetic group (87.8 ± 11.2 bpm; mean ± SD than in the control group (72.9 ± 7.8 bpm, P<0.05. The increase of heart rate at 5 s of tilting was 11.8 ± 6.5 bpm in diabetic patients and 17.6 ± 6.2 bpm in the control group (P<0.05. Systemic arterial pressure and RSA analysis did not reveal significant differences between groups. Diabetes intragroup analysis revealed two behaviors: 10 patients with close to normal findings and 7 with significant abnormalities in terms of RSA, with the latter subgroup presenting one or more abnormalities in other tests and clear evidence of cardiovascular autonomic dysfunction. End-expiratory flows were significantly lower in diabetic patients than in the control group (P<0.05. Pulmonary function tests before and after atropine administration demonstrated comparable responses by both groups. Type 2 diabetic patients have cardiac autonomic dysfunction that is not associated with bronchomotor tone alterations, probably reflecting a less severe impairment than that of type 1 diabetes mellitus. Yet, a reduction of end-expiratory flow was detected.

  3. Abnormal sodium current properties contribute to cardiac electrical and contractile dysfunction in a mouse model of myotonic dystrophy type 1.

    Science.gov (United States)

    Algalarrondo, Vincent; Wahbi, Karim; Sebag, Frédéric; Gourdon, Geneviève; Beldjord, Chérif; Azibi, Kamel; Balse, Elise; Coulombe, Alain; Fischmeister, Rodolphe; Eymard, Bruno; Duboc, Denis; Hatem, Stéphane N

    2015-04-01

    Myotonic dystrophy type 1 (DM1) is the most common neuromuscular disorder and is associated with cardiac conduction defects. However, the mechanisms of cardiac arrhythmias in DM1 are unknown. We tested the hypothesis that abnormalities in the cardiac sodium current (INa) are involved, and used a transgenic mouse model reproducing the expression of triplet expansion observed in DM1 (DMSXL mouse). The injection of the class-I antiarrhythmic agent flecainide induced prominent conduction abnormalities and significantly lowered the radial tissular velocities and strain rate in DMSXL mice compared to WT. These abnormalities were more pronounced in 8-month-old mice than in 3-month-old mice. Ventricular action potentials recorded by standard glass microelectrode technique exhibited a lower maximum upstroke velocity [dV/dt](max) in DMSXL. This decreased [dV/dt](max) was associated with a 1.7 fold faster inactivation of INa in DMSXL myocytes measured by the whole-cell patch-clamp technique. Finally in the DMSXL mouse, no mutation in the Scn5a gene was detected and neither cardiac fibrosis nor abnormalities of expression of the sodium channel protein were observed. Therefore, alterations in the sodium current markedly contributed to electrical conduction block in DM1. This result should guide pharmaceutical and clinical research toward better therapy for the cardiac arrhythmias associated with DM1.

  4. Cardiac potassium channel subtypes

    DEFF Research Database (Denmark)

    Schmitt, Nicole; Grunnet, Morten; Olesen, Søren-Peter

    2014-01-01

    About 10 distinct potassium channels in the heart are involved in shaping the action potential. Some of the K(+) channels are primarily responsible for early repolarization, whereas others drive late repolarization and still others are open throughout the cardiac cycle. Three main K(+) channels...

  5. Disruption of Ah Receptor Signaling during Mouse Development Leads to Abnormal Cardiac Structure and Function in the Adult.

    Directory of Open Access Journals (Sweden)

    Vinicius S Carreira

    Full Text Available The Developmental Origins of Health and Disease (DOHaD Theory proposes that the environment encountered during fetal life and infancy permanently shapes tissue physiology and homeostasis such that damage resulting from maternal stress, poor nutrition or exposure to environmental agents may be at the heart of adult onset disease. Interference with endogenous developmental functions of the aryl hydrocarbon receptor (AHR, either by gene ablation or by exposure in utero to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, a potent AHR ligand, causes structural, molecular and functional cardiac abnormalities and altered heart physiology in mouse embryos. To test if embryonic effects progress into an adult phenotype, we investigated whether Ahr ablation or TCDD exposure in utero resulted in cardiac abnormalities in adult mice long after removal of the agent. Ten-months old adult Ahr-/- and in utero TCDD-exposed Ahr+/+ mice showed sexually dimorphic abnormal cardiovascular phenotypes characterized by echocardiographic findings of hypertrophy, ventricular dilation and increased heart weight, resting heart rate and systolic and mean blood pressure, and decreased exercise tolerance. Underlying these effects, genes in signaling networks related to cardiac hypertrophy and mitochondrial function were differentially expressed. Cardiac dysfunction in mouse embryos resulting from AHR signaling disruption seems to progress into abnormal cardiac structure and function that predispose adults to cardiac disease, but while embryonic dysfunction is equally robust in males and females, the adult abnormalities are more prevalent in females, with the highest severity in Ahr-/- females. The findings reported here underscore the conclusion that AHR signaling in the developing heart is one potential target of environmental factors associated with cardiovascular disease.

  6. ECG-Based Measurements of Drug-induced Repolarization Changes

    DEFF Research Database (Denmark)

    Bhuiyan, Tanveer Ahmed

    The purpose of this thesis is to investigate the abnormal repolarization both in the cellular and the surface ECG along with their relationship. It has been identified that the certain morphological changes of the monophasic action potential are predictor of TdP arrhythmia. Therefore the proporti......The purpose of this thesis is to investigate the abnormal repolarization both in the cellular and the surface ECG along with their relationship. It has been identified that the certain morphological changes of the monophasic action potential are predictor of TdP arrhythmia. Therefore...... the proportional changes of the surface ECG which corresponds to the arrhythmia-triggering MAP morphology is warranted to increase the confidence of determining cardiotoxicity of drugs....

  7. Advising a cardiac disease gene positive yet phenotype negative or borderline abnormal athlete: is sporting disqualification really necessary?

    Science.gov (United States)

    Richard, Pascale; Denjoy, Isabelle; Fressart, Véronique; Wilson, Mathew G; Carré, François; Charron, Philippe

    2012-11-01

    The sudden cardiac death (SCD) of an athlete is a rare and tragic event, often caused by a number of inherited heart muscle disorders, namely the cardiomyopathies and primary arrhythmia syndromes (also known as cardiac ion channelopathies). Recent advances in the understanding of the molecular genetics of these heritable cardiovascular diseases present new challenges for clinicians who manage athletes with these types of heart muscle conditions. Unfortunately, the clinical heterogeneity of many of these SCD diseases are also matched by the genotypic heterogeneity associated with the pathogenesis of the disease. A particularly challenging situation arises when the sports physician and attending cardiologist are presented with an athlete who demonstrates a familial context of inherited cardiac disease or presents mild cardiac abnormalities suggestive of inherited cardiac disease. Alongside the complete cardiac evaluation, genetic testing may be proposed as an additional diagnostic tool in this clinical conundrum. However, debate still remains on how extensive the screening should be, in particular the use and interpretation of genetic testing in that setting. The aim of this review is to examine the role of genetic testing within the diagnostic algorithm of preparticipation screening of athletes. This will be achieved by providing the sports medicine physician with simple current cardiac genetic knowledge for the main inherited cardiac conditions known to cause SCD. Furthermore, it will examine current knowledge for the role of genetic testing upon the prediction of SCD, concluding with its impact on the sport eligibility and disqualification conundrum using case examples from our genetic testing laboratory.

  8. Assessment of cardiac sympathetic nerve abnormalities by {sup 123}I-MIBG (metaiodobenzylguanidine) myocardial scintigraphy in diabetic patients undergoing hemodialysis

    Energy Technology Data Exchange (ETDEWEB)

    Ohashi, Hiroshige; Oda, Hiroshi; Matsuno, Yukihiko [Prefectural Gifu Hospital (Japan)] [and others

    1995-05-01

    We compared cardiac sympathetic nerve abnormalities in patients hemodialyzed because of diabetic nephropathy (DN, n=18) and chronic glomerulonephritis (CGN, n=21). {sup 123}I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy was performed in this study. SPECT and anterior planar myocardial images were obtained 15 minutes after (initial images) and 4 hours after (delayed images) an injection of MIBG. The following results were obtained: (1) SPECT showed more defects in DN than in CGN. (2) The heart to superior mediastinum uptake ratio (H/M) was lower in DN than in CGN. These findings suggest that myocardial uptake of MIBG in DN is significantly impaired because of cardiac sympathetic nerve abnormalities. These abnormalities may affect the prognosis in DN. (author).

  9. Procainamide and lidocaine produce dissimilar changes in ventricular repolarization and arrhythmogenicity in guinea-pig.

    Science.gov (United States)

    Osadchii, Oleg E

    2014-08-01

    Procainamide is class Ia Na(+) channel blocker that may prolong ventricular repolarization secondary to inhibition of IK r , the rapid component of the delayed rectifier K(+) current. In contrast to selective IN a blockers such as lidocaine, procainamide was shown to produce arrhythmogenic effects in the clinical setting. This study examined whether pro-arrhythmic responses to procainamide may be accounted for by drug-induced repolarization abnormalities including impaired electrical restitution kinetics, spatial gradients in action potential duration (APD), and activation-to-repolarization coupling. In perfused guinea-pig hearts, procainamide was found to prolong the QT interval on ECG and left ventricular (LV) epicardial monophasic APD, increased the maximum slope of electrical restitution, enhanced transepicardial APD variability, and eliminated the inverse correlation between the local APD and activation time values determined at distinct epicardial recording sites prior to drug infusion. In contrast, lidocaine had no effect on electrical restitution, the degree of transepicardial repolarization heterogeneities, and activation-to-repolarization coupling. Spontaneous episodes of monomorphic ventricular tachycardia were observed in 57% of procainamide-treated heart preparations. No arrhythmia was induced by lidocaine. In summary, this study suggests that abnormal changes in repolarization may contribute to pro-arrhythmic effects of procainamide.

  10. Sodium valproate-induced congenital cardiac abnormalities in mice are associated with the inhibition of histone deacetylase

    Directory of Open Access Journals (Sweden)

    Rollo Johnathon C

    2010-03-01

    Full Text Available Abstract Background Valproic acid, a widely used anticonvulsant drug, is a potent teratogen resulting in various congenital abnormalities. However, the mechanisms underlying valproic acid induced teratogenesis are nor clear. Recent studies indicate that histone deacetylase is a direct target of valproic acid. Methods In the present study, we have used histological analysis and RT-PCR assays to examine the cardiac abnormalities in mice treated with sodium valproate (NaVP and determined the effects of NaVP on histone deacetylase activity and the expression of heart development-related genes in mouse myocardial cells. Results The experimental data show that NaVP can induce cardiac abnormalities in fetal mice in a dose-dependent manner. NaVP causes a dose-dependent inhibition of hitone deacetylase (HDAC activity in mouse myocardial cells. However, the expression levels of HDAC (both HDAC1 and HDAC2 are not significantly changed in fetal mouse hearts after administration of NaVP in pregnant mice. The transcriptional levels of other heart development-related genes, such as CHF1, Tbx5 and MEF2, are significantly increased in fetal mouse hearts treated with NaVP. Conclusions The study indicates that administration of NaVP in pregnant mice can result in various cardiac abnormalities in fetal hearts, which is associated with an inhibition of histone deacetylase without altering the transcription of this enzyme.

  11. Hypertrophic cardiomyopathy: Cardiac structural and microvascular abnormalities as evaluated with multi-parametric MRI

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yu-Dong, E-mail: njmu_zyd@163.com [Department of Radiology, the First Affiliated Hospital with Nanjing Medical University (China); Li, Meijiao, E-mail: newgljyk@163.com [Department of Radiology, Peking University First Hospital (China); Qi, Liang, E-mail: qiliang1120@126.com [Department of Radiology, the First Affiliated Hospital with Nanjing Medical University (China); Wu, Chen-Jiang, E-mail: njmu_wcj@163.com [Department of Radiology, the First Affiliated Hospital with Nanjing Medical University (China); Wang, Xiaoying, E-mail: cjr.wangxiaoying@vip.163.com [Department of Radiology, Peking University First Hospital (China)

    2015-08-15

    Highlights: • LGE-present HCM had lower K{sup trans}, higher V{sub e} and MTT against LGE-absent HCM and normal group. • LGE-absent had significantly higher V{sub e} and MTT against normal group. • K{sup trans} was not changed between LGE-absent and normal group Microcirculatory dysfunction in HCM closely correlated to structural abnormality. - Abstract: Purpose: To determine the relationship between myocardial structural and microvascular abnormality in hypertrophic cardiomyopathy (HCM) by multi-parametric cardiac MRI. Materials and methods: Twenty-four HCM and eighteen controls were retrospectively included. Left ventricle mass (LVM), LV end-systolic and end-diastolic volume (LVESV, LVEDV), LV ejection fraction (LVEF), and 16-segment wall thickness at ES and ED (SESWT, SEDWT) were assessed with a 2D cine-MRI. Myocardial perfusion (reflected by K{sup trans}), interstitial volume (V{sub e}) and mean transmit time (MTT) were evaluated with a model-dependent dynamic contrast-enhanced MRI. Myocardial fibrosis was assessed with late gadolinium enhancement (LGE) imaging. Results: K{sup trans} was significantly decreased in LGE-present (0.74 ± 0.15 mL/g/min) against LGE-absent (0.55 ± 0.14 mL/g/min, p = 0.030) and normal group (0.81 ± 0.32 mL/g/min, p < 0.001), but was unchanged in LGE-absent against normal group (p > 0.05). V{sub e} and MTT were significantly increased in LGE-present (V{sub e}: 26.7 ± 15.7%; MTT: 28.6 ± 21.3 s) against LGE-absent (37.6 ± 18.3%; 49.8 ± 30.5 s) and normal group (19.7 ± 6.9%; 15.1 ± 3.9 s; all p < 0.001), and were significantly increased in LGE-absent against normal group (p < 0.001). LGE significantly correlated to K{sup trans}, V{sub e}, MTT, and SESWT (ρ = 0.232, −0.247, −0.443, and −0.207, respectively). K{sup trans} negatively correlated to SEDWT and SESWT (ρ = −0.224 and −0.231). V{sub e} and MTT positively correlated to SEDWT (V{sub e}: ρ = 0.223; MTT: ρ = 0.239) and SESWT (V{sub e}: ρ = 0.248; MTT:

  12. Genetic association study of QT interval highlights role for calcium signaling pathways in myocardial repolarization

    Science.gov (United States)

    Arking, Dan E.; Pulit, Sara L.; Crotti, Lia; van der Harst, Pim; Munroe, Patricia B.; Koopmann, Tamara T.; Sotoodehnia, Nona; Rossin, Elizabeth J.; Morley, Michael; Wang, Xinchen; Johnson, Andrew D.; Lundby, Alicia; Gudbjartsson, Daníel F.; Noseworthy, Peter A.; Eijgelsheim, Mark; Bradford, Yuki; Tarasov, Kirill V.; Dörr, Marcus; Müller-Nurasyid, Martina; Lahtinen, Annukka M.; Nolte, Ilja M.; Smith, Albert Vernon; Bis, Joshua C.; Isaacs, Aaron; Newhouse, Stephen J.; Evans, Daniel S.; Post, Wendy S.; Waggott, Daryl; Lyytikäinen, Leo-Pekka; Hicks, Andrew A.; Eisele, Lewin; Ellinghaus, David; Hayward, Caroline; Navarro, Pau; Ulivi, Sheila; Tanaka, Toshiko; Tester, David J.; Chatel, Stéphanie; Gustafsson, Stefan; Kumari, Meena; Morris, Richard W.; Naluai, Åsa T.; Padmanabhan, Sandosh; Kluttig, Alexander; Strohmer, Bernhard; Panayiotou, Andrie G.; Torres, Maria; Knoflach, Michael; Hubacek, Jaroslav A.; Slowikowski, Kamil; Raychaudhuri, Soumya; Kumar, Runjun D.; Harris, Tamara B.; Launer, Lenore J.; Shuldiner, Alan R.; Alonso, Alvaro; Bader, Joel S.; Ehret, Georg; Huang, Hailiang; Kao, W.H. Linda; Strait, James B.; Macfarlane, Peter W.; Brown, Morris; Caulfield, Mark J.; Samani, Nilesh J.; Kronenberg, Florian; Willeit, Johann; Smith, J. Gustav; Greiser, Karin H.; zu Schwabedissen, Henriette Meyer; Werdan, Karl; Carella, Massimo; Zelante, Leopoldo; Heckbert, Susan R.; Psaty, Bruce M.; Rotter, Jerome I.; Kolcic, Ivana; Polašek, Ozren; Wright, Alan F.; Griffin, Maura; Daly, Mark J.; Arnar, David O.; Hólm, Hilma; Thorsteinsdottir, Unnur; Denny, Joshua C.; Roden, Dan M.; Zuvich, Rebecca L.; Emilsson, Valur; Plump, Andrew S.; Larson, Martin G.; O'Donnell, Christopher J.; Yin, Xiaoyan; Bobbo, Marco; D'Adamo, Adamo P.; Iorio, Annamaria; Sinagra, Gianfranco; Carracedo, Angel; Cummings, Steven R.; Nalls, Michael A.; Jula, Antti; Kontula, Kimmo K.; Marjamaa, Annukka; Oikarinen, Lasse; Perola, Markus; Porthan, Kimmo; Erbel, Raimund; Hoffmann, Per; Jöckel, Karl-Heinz; Kälsch, Hagen; Nöthen, Markus M.; consortium, HRGEN; den Hoed, Marcel; Loos, Ruth J.F.; Thelle, Dag S.; Gieger, Christian; Meitinger, Thomas; Perz, Siegfried; Peters, Annette; Prucha, Hanna; Sinner, Moritz F.; Waldenberger, Melanie; de Boer, Rudolf A.; Franke, Lude; van der Vleuten, Pieter A.; Beckmann, Britt Maria; Martens, Eimo; Bardai, Abdennasser; Hofman, Nynke; Wilde, Arthur A.M.; Behr, Elijah R.; Dalageorgou, Chrysoula; Giudicessi, John R.; Medeiros-Domingo, Argelia; Barc, Julien; Kyndt, Florence; Probst, Vincent; Ghidoni, Alice; Insolia, Roberto; Hamilton, Robert M.; Scherer, Stephen W.; Brandimarto, Jeffrey; Margulies, Kenneth; Moravec, Christine E.; Fabiola Del, Greco M.; Fuchsberger, Christian; O'Connell, Jeffrey R.; Lee, Wai K.; Watt, Graham C.M.; Campbell, Harry; Wild, Sarah H.; El Mokhtari, Nour E.; Frey, Norbert; Asselbergs, Folkert W.; Leach, Irene Mateo; Navis, Gerjan; van den Berg, Maarten P.; van Veldhuisen, Dirk J.; Kellis, Manolis; Krijthe, Bouwe P.; Franco, Oscar H.; Hofman, Albert; Kors, Jan A.; Uitterlinden, André G.; Witteman, Jacqueline C.M.; Kedenko, Lyudmyla; Lamina, Claudia; Oostra, Ben A.; Abecasis, Gonçalo R.; Lakatta, Edward G.; Mulas, Antonella; Orrú, Marco; Schlessinger, David; Uda, Manuela; Markus, Marcello R.P.; Völker, Uwe; Snieder, Harold; Spector, Timothy D.; Ärnlöv, Johan; Lind, Lars; Sundström, Johan; Syvänen, Ann-Christine; Kivimaki, Mika; Kähönen, Mika; Mononen, Nina; Raitakari, Olli T.; Viikari, Jorma S.; Adamkova, Vera; Kiechl, Stefan; Brion, Maria; Nicolaides, Andrew N.; Paulweber, Bernhard; Haerting, Johannes; Dominiczak, Anna F.; Nyberg, Fredrik; Whincup, Peter H.; Hingorani, Aroon; Schott, Jean-Jacques; Bezzina, Connie R.; Ingelsson, Erik; Ferrucci, Luigi; Gasparini, Paolo; Wilson, James F.; Rudan, Igor; Franke, Andre; Mühleisen, Thomas W.; Pramstaller, Peter P.; Lehtimäki, Terho J.; Paterson, Andrew D.; Parsa, Afshin; Liu, Yongmei; van Duijn, Cornelia; Siscovick, David S.; Gudnason, Vilmundur; Jamshidi, Yalda; Salomaa, Veikko; Felix, Stephan B.; Sanna, Serena; Ritchie, Marylyn D.; Stricker, Bruno H.; Stefansson, Kari; Boyer, Laurie A.; Cappola, Thomas P.; Olsen, Jesper V.; Lage, Kasper; Schwartz, Peter J.; Kääb, Stefan; Chakravarti, Aravinda; Ackerman, Michael J.; Pfeufer, Arne; de Bakker, Paul I.W.; Newton-Cheh, Christopher

    2014-01-01

    The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal Mendelian Long QT Syndrome (LQTS). Using a genome-wide association and replication study in up to 100,000 individuals we identified 35 common variant QT interval loci, that collectively explain ∼8-10% of QT variation and highlight the importance of calcium regulation in myocardial repolarization. Rare variant analysis of 6 novel QT loci in 298 unrelated LQTS probands identified coding variants not found in controls but of uncertain causality and therefore requiring validation. Several newly identified loci encode for proteins that physically interact with other recognized repolarization proteins. Our integration of common variant association, expression and orthogonal protein-protein interaction screens provides new insights into cardiac electrophysiology and identifies novel candidate genes for ventricular arrhythmias, LQTS,and SCD. PMID:24952745

  13. Cardiac abnormalities in adults with the attenuated form of mucopolysaccharidosis type I

    NARCIS (Netherlands)

    O.I.I. Soliman (Osama Ibrahim Ibrahim); R.G.M. Timmermans (Remco); A. Nemes (Attila); W.B. Vletter (Wim); J.H.P. Wilson (Paul); F.J. ten Cate (Folkert); M.L. Geleijnse (Marcel)

    2007-01-01

    textabstractBackground: Cardiac involvement in mucopolysaccharidosis type I (MPS I) has been studied primarily in its most severe forms. Cardiac involvement, particularly left ventricular (LV) systolic and diastolic function, in the attenuated form of MPS I is less well known. Methods: Cardiac funct

  14. Detection of Left Ventricular Regional Dysfunction and Myocardial Abnormalities Using Complementary Cardiac Magnetic Resonance Imaging in Patients with Systemic Sclerosis without Cardiac Symptoms: A Pilot Study.

    Science.gov (United States)

    Kobayashi, Yasuyuki; Kobayashi, Hitomi; T Giles, Jon; Yokoe, Isamu; Hirano, Masaharu; Nakajima, Yasuo; Takei, Masami

    2016-01-01

    Objective We sought to detect the presence of left ventricular regional dysfunction and myocardial abnormalities in systemic sclerosis (SSc) patients without cardiac symptoms using a complementary cardiac magnetic resonance (CMR) imaging approach. Methods Consecutive patients with SSc without cardiac symptoms and healthy controls underwent CMR on a 1.5 T scanner. The peak systolic regional function in the circumferential and radial strain (Ecc, % and Err, %) were calculated using a feature tracking analysis on the mid-left ventricular slices obtained with cine MRI. In addition, we investigated the myocardial characteristics by contrast MRI. Pharmacological stress and rest perfusion scans were performed to assess perfusion defect (PD) due to micro- or macrovascular impairment, and late gadolinium enhancement (LGE) images were obtained for the assessment of myocarditis and/or fibrosis. Results We compared 15 SSc patients with 10 healthy controls. No statistically significant differences were observed in the baseline characteristics between the patients and healthy controls. The mean peak Err and Ecc of all segments was significantly lower in the patients than the controls (p=0.011 and p=0.003, respectively). Four patients with LGE (28.6%) and seven patients with PD (50.0%) were observed. PD was significantly associated with digital ulcers (p=0.005). Utilizing a linear regression model, the presence of myocardial LGE was significantly associated with the peak Ecc (p=0.024). After adjusting for age, the association between myocardial LGE and the peak Ecc was strengthened. Conclusion A subclinical myocardial involvement, as detected by CMR, was prevalent in the SSc patients without cardiac symptoms. Regional dysfunction might predict the myocardial abnormalities observed in SSc patients without cardiac symptoms.

  15. 心脏再同步治疗对心肌复极离散度的影响%Influence of cardiac resynchronization therapy on myocardial dispersion of repolarization

    Institute of Scientific and Technical Information of China (English)

    陈建明; 孙国建; 吴巧元; 郑良荣; 沈法荣; 王志军; 凌锋; 金红峰; 何浪; 钟诚; 陈旭娇; 汤益民

    2009-01-01

    目的 观察心室不同位点起搏时心电图上心肌复极标志的变化,了解以双心室起搏技术为核心的心脏再同步治疗(CRT)对心肌复极离散的影响.方法 入选接受CRT植入的患者在起搏器植入后1周内记录12导联心电图,分别将起搏器程控为无起搏、右心室内膜下起搏(RV-EndoP)、左心室外膜起搏(LV-EpiP)及双心室同步起搏(BivP)四种不同状态并记录心电图.阅读不同起搏位点时的QRS时限、QT间期及TP.E时限.QTc用Bazett公式(QTc=实测QT/(RR)1/27进行矫正.结果 基线QTc为(489.2±51.2)ms,而RV-EndoP、LV-EpiP起搏导致QTc明显延长[RV-EndoP(537.3±45.7)ms,P<0.05;LV-EpiP(592.4±60.2)ms,P<0.001],而BivP起搏为(491.3±52.7)ms,P>0.05;基线TP.E(113.8±15.7)ms,RV-EndoP、LV-EpiP均导致TP.E明显延长(RV-EndoP(124.8±24.7)ms,P<0.05;LVEpi P(133.3±37.8)ms,P<0.005],BivP时TP.E时限为(109.9±17.1)ms,有轻度缩短,但差异没有统计学意义(P>0.05).结论 左心室外膜起搏可明显延长心肌复极离散指标;双心窒同步起搏可减少由单纯左心室外膜起搏引起的复檄离散度的增大.%Objective To investigate the characteristic of electrocardiogram pacingin different sites and the effects of cardiac resynchronization therapy(CRT)on the dispersion of the repolarization.Methods Forty patients with biventricular pacemaker were included in this study.Standard surface ECGs were recorded continuously while the pacemaker was programmed to biventricular pacing,left ventricular(LV)pacing,right ventricular (RV)pacing and no pacing mode.ECG analysis was performed by electrophysiology specialists.The parameters of repelarization dispersion included QRS duration,QT interval and TP.E duration,and OTc interval were corrected for heart rate using Baser formula.Results When baseline QTc duration was(489.2±51.2)ms,RV-EndoP and LV-EpiP pacing induced QTc increase significantly[RV-EndoP(537.3±45.7)ms,P<0.05;LV-EpiP (592.4±60.2)ms,P<0

  16. Genetic association study of QT interval highlights role for calcium signaling pathways in myocardial repolarization

    DEFF Research Database (Denmark)

    Arking, Dan E; Pulit, Sara L; Crotti, Lia

    2014-01-01

    The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal mendelian long-QT syndrome (LQTS). Usi...

  17. Genetic association study of QT interval highlights role for calcium signaling pathways in myocardial repolarization

    NARCIS (Netherlands)

    Arking, Dan E.; Pulit, Sara L.; Crotti, Lia; Van der Harst, Pim; Munroe, Patricia B.; Koopmann, Tamara T.; Sotoodehnia, Nona; Rossin, Elizabeth J.; Morley, Michael; Wang, Xinchen; Johnson, Andrew D.; Lundby, Alicia; Gudbjartsson, Daniel F.; Noseworthy, Peter A.; Eijgelsheim, Mark; Bradford, Yuki; Tarasov, Kirill V.; Dorr, Marcus; Miiller-Nurasyid, Martina; Lahtinen, Annukka M.; Nolte, Ilja M.; Smith, Albert Vernon; Bis, Joshua C.; Isaacs, Aaron; Newhouse, Stephen J.; Evans, Daniel S.; Post, Wendy S.; Waggott, Daryl; Lyytikainen, Leo-Pekka; Hicks, Andrew A.; Eisele, Lewin; Ellinghaus, David; Hayward, Caroline; Navarro, Pau; Ulivi, Sheila; Tanaka, Toshiko; Tester, David J.; Chatel, Stephanie; Gustafsson, Stefan; Kumari, Meena; Morris, Richard W.; Naluai, Asa T.; Padmanabhan, Sandosh; Kluttig, Alexander; Strohmer, Bernhard; Panayiotou, Andrie G.; Torres, Maria; Knoflach, Michael; Hubacek, Jaroslav A.; Slowikowski, Kamil; Raychaudhuri, Soumya; Kumar, Runjun D.; Harris, Tamara B.; Launer, Lenore J.; Shuldiner, Alan R.; Alonso, Alvaro; Bader, Joel S.; EhreT, Georg; Huang, Hailiang; Kao, W. H. Linda; Strait, James B.; Macfarlane, Peter W.; Brown, Morris; Caulfield, Mark J.; Samani, Nilesh J.; Kronenberg, Florian; Willeit, Johann; Smith, J. Gustav; Greiser, Karin H.; Schwabedissen, Henriette Meyer Zu; Werdan, Karl; Carella, Massimo; Zelante, Leopoldo; Heckbert, Susan R.; Psaty, Bruce M.; Rotter, Jerome I.; Kolcic, Ivana; Poagek, Ozren; Wright, Alan F.; Griffin, Maura; Daly, Mark J.; Arnar, David O.; Holm, Hilma; Thorsteinsdottir, Unnur; Denny, Joshua C.; Roden, Dan M.; Zuvich, Rebecca L.; Emilsson, Valur; Plump, Andrew S.; Larson, Martin G.; O'Donnell, Christopher J.; Yin, Xiaoyan; Bobboll, Marco; D'Adamo, Adamo P.; Iorio, Annamaria; Sinagra, Gianfranco; Carracedo, Angel; Cummings, Steven R.; Nalls, Michael A.; Jula, Antti; Kontula, Kimmo K.; Marjamaa, Annukka; Oikarinen, Lasse; Perola, Markus; Porthan, Kimmo; Erbe, Raimund; Hoffmann, Per; Jockel, Karl-Heinz; Kalsch, Hagen; Nothen, Markus M.; Den Hoed, Marcel; Loos, Ruth J. F.; Thelle, Dag S.; Gieger, Christian; Meitinger, Thomas; Perz, Siegfried; Peters, Annette; Pruchal, Hanna; Sinner, Moritz F.; Waldenberger, Melanie; De Boer, Rudolf A.; Franke, Lude; Van der Vleuten, Pieter A.; Beckmann, Britt Maria; Martens, Eimo; Bardail, Abdennasser; Hofman, Nynke; Wilde, Arthur A. M.; Behr, Elijah R.; Dalageorgou, Chrysoula; Giudicessi, John R.; Medeiros-Domingo, Argelia; Barc, Julien; Kyndt, Florence; Probst, Vincent; Ghidoni, Alice; Insolia, Roberto; Hamilton, Robert M.; Scherer, Stephen W.; Brandimarto, Jeffrey; Margulies, Kenneth; Moravec, Christine E.; Del Greco, Fabiola; Fuchsberger, Christian; O'Connell, Jeffrey R.; Lee, Wai K.; Watt, Graham C. M.; Campbell, Harry; Wild, Sarah H.; El Mokhtari, Nour E.; Frey, Norbert; Asselbergs, Folkert W.; Mateo Leach, Irene; Navis, Gerjan; Van den Berg, Maarten P.; Van Veldhuisen, Dirk J.; Kellis, Manolis; Krijthe, Bouwe P.; Franco, Oscar H.; Hofman, Albert; Kors, Jan A.; Uitterlinden, Andre G.; Witteman, Jacqueline C. M.; Kedenko, Lyudmyla; Lamina, Claudia; Oostra, Ben A.; Abecasis, Goncalo R.; Lakatta, Edward G.; Mulas, Antonella; Orru, Marco; Schlessinger, David; Uda, Manuela; Markus, Marcello R. P.; Volker, Uwe; Snieder, Harold; Spector, Timothy D.; Arnlov, Johan; Lind, Lars; Sundstrom, Johan; Syvanen, Ann-Christine; Kivimaki, Mika; Kahonen, Mika; Mononen, Nina; Raitakari, I. T.; Viikari, Jorma S.; Adamkova, Vera; Kiech, Stefan; Brion, Maria; Nicolaides, Andrew N.; Paulweber, Bernhard; Haerting, Johannes; Dominiczak, Anna F.; Nyberg, Fredrik; Whincup, Peter H.; Hingorani, Aroon D.; Schott, Jean-Jacques; Bezzina, Connie R.; Ingelsson, Erik; Ferrucci, Luigi; Gaspariniin, Paolo; Wilson, James F.; Rudan, Igor; Franke, Andre; Miihleisen, Thomas W.; Pramstaller, Peter P.; Lehtimaki, Terho J.; Paterson, Andrew D.; Parsa, Afshin; Liu, Yongmei; Van Duijn, Cornelia M.; Siscovick, David S.; Gudnason, Vilmundur; Jamshidi, Yalda; Salomaa, Veikko; Felix, Stephan B.; Sanna, Serena; Ritchie, Marylyn D.; Stricker, Bruno H.; Stefansson, Karl; Boyer, Laurie A.; Cappola, Thomas P.; Olsen, Jesper V.; Lage, Kasper; Schwartz, Peter J.; Kaab, Stefan; Chakravarti, Aravinda; Ackerman, Michael J.; Pfeufer, Arne; De Bakker, Paul I. W.; Newton-Cheh, Christopher

    2014-01-01

    The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal mendelian long-QT syndrome (LQTS). Using

  18. Genetic association study of QT interval highlights role for calcium signaling pathways in myocardial repolarization

    NARCIS (Netherlands)

    D.E. Arking (Dan); S.L. Pulit (Sara); L. Crotti (Lia); P. van der Harst (Pim); P. Munroe (Patricia); T.T. Koopmann (Tamara); N. Sotoodehnia (Nona); E. Rossin (Elizabeth); M. Morley (Michael); X. Wang (Xinchen); A.D. Johnson (Andrew); A. Lundby (Alicia); D.F. Gudbjartsson (Daniel); P.A. Noseworthy (Peter); M. Eijgelsheim (Mark); Y. Bradford (Yuki); K.V. Tarasov (Kirill); M. Dörr (Marcus); M. Müller-Nurasyid (Martina); A.M. Lahtinen (Annukka); I.M. Nolte (Ilja); G.D. Smith; J.C. Bis (Joshua); A.J. Isaacs (Aaron); S.J. Newhouse (Stephen); D.S. Evans (Daniel); W.S. Post (Wendy S.); D. Waggott (Daryl); L.-P. Lyytikäinen (Leo-Pekka); A.A. Hicks (Andrew); L. Eisele (Lewin); D. Ellinghaus (David); C. Hayward (Caroline); P. Navarro (Pau); S. Ulivi (Shelia); T. Tanaka (Toshiko); D.J. Tester (David); S. Chatel (Stéphanie); S. Gustafsson (Stefan); M. Kumari (Meena); R. Morris (Richard); A.T. Naluai (Asa); S. Padmanabhan (Sandosh); A. Kluttig (Alexander); B. Strohmer (Bernhard); A.G. Panayiotou (Andrie); M. Torres (Maria); M. Knoflach (Michael); J.A. Hubacek (Jaroslav A.); K. Slowikowski (Kamil); S. Raychaudhuri (Soumya); R.D. Kumar (Runjun); T.B. Harris (Tamara); L.J. Launer (Lenore); A.R. Shuldiner (Alan); A. Alonso (Alvaro); J.S. Bader (Joel); G.B. Ehret (Georg); H. Huang (Hailiang); W.H.L. Kao (Wen); J.B. Strait (James); P.W. Macfarlane (Peter); M.J. Brown (Morris); M. Caulfield (Mark); N.J. Samani (Nilesh); F. Kronenberg (Florian); J. Willeit (Johann); J.G. Smith (J. Gustav); K.H. Greiser (Karin Halina); H.M. Zu Schwabedissen (Henriette Meyer); K. Werdan (Karl); C. Carella (Cintia); L. Zelante (Leopoldo); S.R. Heckbert (Susan); B.M. Psaty (Bruce); J.I. Rotter (Jerome); I. Kolcic (Ivana); O. Polasek (Ozren); A.F. Wright (Alan); M. Griffin (Maura); M.J. Daly (Mark); D.O. Arnar (David); H. Hólm (Hilma); U. Thorsteinsdottir (Unnur); J.C. Denny (Joshua); D.M. Roden (Dan); R.L. Zuvich (Rebecca); V. Emilsson (Valur); A.S. Plump (Andrew); M.G. Larson (Martin); C.J. O'Donnell (Christopher); X. Yin (Xiaoyan); M. Bobbo (Marco); P. d' Adamo (Pio); A. Iorio (Annamaria); G. Sinagra (Gianfranco); A. Carracedo (Angel); S.R. Cummings (Steven); M.A. Nalls (Michael); A. Jula (Antti); K.K. Kontula (Kimmo); A. Marjamaa (Annukka); L. Oikarinen (Lasse); M. Perola (Markus); K. Porthan (Kimmo); R. Erbel (Raimund); P. Hoffmann (Per); K.-H. Jöckel (Karl-Heinz); H. Kälsch (Hagen); M.M. Nöthen (Markus); M. den Hoed (Marcel); R.J.F. Loos (Ruth); D.S. Thelle (Dag); C. Gieger (Christian); T. Meitinger (Thomas); S. Perz (Siegfried); A. Peters (Annette); H. Prucha (Hanna); M.F. Sinner (Moritz); M. Waldenberger (Melanie); R.A. de Boer (Rudolf); L. Franke (Lude); P.A. van der Vleuten (Pieter); B.M. Beckmann (Britt); E. Martens (Eimo); A. Bardai (Abdennasser); N. Hofman (Nynke); A.A.M. Wilde (Arthur); E.R. Behr (Elijah ); C. Dalageorgou (Chrysoula); J.R. Giudicessi (John); A. Medeiros-Domingo (Argelia); J. Barc (Julien); F. Kyndt (Florence); V. Probst (Vincent); A. Ghidoni (Alice); R. Insolia (Roberto); R.M. Hamilton (Robert); S.W. Scherer (Stephen); J. Brandimarto (Jeffrey); K. Margulies (Kenneth); C.E. Moravec (Christine); F. Del Greco M (Fabiola); C. Fuchsberger (Christian); J.R. O'Connell (Jeffery); W.K. Lee (Wai); G.C.M. Watt (Graham); H. Campbell (Harry); S.H. Wild (Sarah); N.E. El Mokhtari (Nour); N. Frey (Norbert); F.W. Asselbergs (Folkert); I.M. Leach (Irene Mateo); G. Navis (Gerjan); M.P. van den Berg (Maarten); D.J. van Veldhuisen (Dirk); M. Kellis (Manolis); B.P. Krijthe (Bouwe); O.H. Franco (Oscar); A. Hofman (Albert); J.A. Kors (Jan); A.G. Uitterlinden (André); J.C.M. Witteman (Jacqueline); L. Kedenko (Lyudmyla); C. Lamina (Claudia); B.A. Oostra (Ben); G.R. Abecasis (Gonçalo); E. Lakatta (Edward); A. Mulas (Antonella); M. Orrù (Marco); D. Schlessinger (David); M. Uda (Manuela); M.R.P. Markus (Marcello R. P.); U. Völker (Uwe); H. Snieder (Harold); T.D. Spector (Timothy); J. Ärnlöv (Johan); L. Lind (Lars); J. Sundstrom (Johan); A.C. Syvanen; M. Kivimaki (Mika); M. Kähönen (Mika); K. Mononen (Kari); O. Raitakari (Olli); J. Viikari (Jorma); V. Adamkova (Vera); S. Kiechl (Stefan); M.-J. Brion (Maria); A.N. Nicolaides (Andrew); B. Paulweber (Bernhard); J. Haerting (Johannes); A. Dominiczak (Anna); F. Nyberg (Fredrik); P.H. Whincup (Peter); A. Hingorani (Aroon); J.-J. Schott (Jean-Jacques); C.R. Bezzina (Connie); E. Ingelsson (Erik); L. Ferrucci (Luigi); P. Gasparini (Paolo); J.F. Wilson (James); I. Rudan (Igor); A. Franke (Andre); T.W. Mühleisen (Thomas); P.P. Pramstaller (Peter Paul); T. Lehtimäki (Terho); A.D. Paterson (Andrew); A. Parsa (Afshin); Y. Liu (Yongmei); C.M. van Duijn (Cock); D.S. Siscovick (David); V. Gudnason (Vilmundur); Y. Jamshidi (Yalda); V. Salomaa (Veikko); S.B. Felix (Stephan); S. Sanna (Serena); M.D. Ritchie (Marylyn); B.H.Ch. Stricker (Bruno); J-A. Zwart (John-Anker); L.A. Boyer (Laurie); T.P. Cappola (Thomas); J.V. Olsen (Jesper); P. Lage (Pedro); P.J. Schwartz (Peter); S. Kääb (Stefan); A. Chakravarti (Aravinda); M. Ackerman (Margaret); A. Pfeufer (Arne); P.I.W. de Bakker (Paul); C. Newton-Cheh (Christopher)

    2014-01-01

    textabstractThe QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal mendelian long-QT syndrome (L

  19. Architecture design of the multi-functional wavelet-based ECG microprocessor for realtime detection of abnormal cardiac events.

    Science.gov (United States)

    Cheng, Li-Fang; Chen, Tung-Chien; Chen, Liang-Gee

    2012-01-01

    Most of the abnormal cardiac events such as myocardial ischemia, acute myocardial infarction (AMI) and fatal arrhythmia can be diagnosed through continuous electrocardiogram (ECG) analysis. According to recent clinical research, early detection and alarming of such cardiac events can reduce the time delay to the hospital, and the clinical outcomes of these individuals can be greatly improved. Therefore, it would be helpful if there is a long-term ECG monitoring system with the ability to identify abnormal cardiac events and provide realtime warning for the users. The combination of the wireless body area sensor network (BASN) and the on-sensor ECG processor is a possible solution for this application. In this paper, we aim to design and implement a digital signal processor that is suitable for continuous ECG monitoring and alarming based on the continuous wavelet transform (CWT) through the proposed architectures--using both programmable RISC processor and application specific integrated circuits (ASIC) for performance optimization. According to the implementation results, the power consumption of the proposed processor integrated with an ASIC for CWT computation is only 79.4 mW. Compared with the single-RISC processor, about 91.6% of the power reduction is achieved.

  20. Significance of cardiac sympathetic nervous system abnormality for predicting vascular events in patients with idiopathic paroxysmal atrial fibrillation

    Energy Technology Data Exchange (ETDEWEB)

    Akutsu, Yasushi; Kaneko, Kyouichi; Kodama, Yusuke; Li, Hui-Ling; Kawamura, Mitsuharu; Asano, Taku; Hamazaki, Yuji; Tanno, Kaoru; Kobayashi, Youichi [Showa University School of Medicine, Division of Cardiology, Department of Medicine, Tokyo (Japan); Suyama, Jumpei; Shinozuka, Akira; Gokan, Takehiko [Showa University School of Medicine, Department of Radiology, Tokyo (Japan)

    2010-04-15

    Neuronal system activity plays an important role for the prognosis of patients with atrial fibrillation (AF). Using {sup 123}I metaiodobenzylguanidine ({sup 123}I-MIBG) scintigraphy, we investigated whether a cardiac sympathetic nervous system (SNS) abnormality would be associated with an increased risk of vascular events in patients with paroxysmal AF. {sup 123}I-MIBG scintigraphy was performed in 69 consecutive patients (67 {+-} 13 years, 62% men) with paroxysmal AF who did not have structural heart disease. SNS integrity was assessed from the heart to mediastinum (H/M) ratio on delayed imaging. Serum concentration of C-reactive protein (CRP) was measured before {sup 123}I-MIBG study. During a mean of 4.5 {+-} 3.6 years follow-up, 19 patients had myocardial infarction, stroke or heart failure (range: 0.2-11.5 years). SNS abnormality (H/M ratio <2.7) and high CRP ({>=}0.3 mg/dl) were associated with the vascular events (58.3% in 14 of 24 patients with SNS abnormality vs 11.1% in 5 of 45 patients without SNS abnormality, p < 0.0001, 52.4% in 11 of 21 patients with high CRP vs 16.7% in 8 of 48 patients without high CRP, p < 0.0001). After adjustment for potential confounding variables such as age, left atrial dimension and left ventricular function, SNS abnormality was an independent predictor of vascular events with a hazard ratio of 4.1 [95% confidence interval (CI): 1.3-12.6, p = 0.014]. Further, SNS abnormality had an incremental and additive prognostic power in combination with high CRP with an adjusted hazard ratio of 4.1 (95% CI: 1.5-10.9, p = 0.006). SNS abnormality is predictive of vascular events in patients with idiopathic paroxysmal AF. (orig.)

  1. Double pharmacological challenge on repolarization opens new avenues for drug safety research

    DEFF Research Database (Denmark)

    Thomsen, Morten Bækgaard

    2007-01-01

    The pharmaceutical industry is testing new potential drugs for their propensity to prolong human cardiac repolarization, and regards this as a sign of proarrhythmic risk. Many studies have dethroned the common perception that prolonged repolarization is a reliable surrogate marker for torsades de...... pointes (TdP) arrhythmia. Both the pharmaceutical industry and the regulatory bodies are neglecting the available proarrhythmia models. In vitro studies have suggested that combined pharmacological hits on repolarization will produce a superior substrate for in vivo proarrhythmia, compared to the single-drug...... assessment. By using consecutive pharmacological challenges, a simple model is proposed, in which combinatorial pharmacology is employed to provoke TdP in the conscious dog. The pharmaceutical industry interested in evaluating the proarrhythmic potential of their present and future drugs now has a simple...

  2. Relation of cardiac abnormalities and CTG-repeat size in myotonic dystrophy.

    Science.gov (United States)

    Finsterer, J; Gharehbaghi-Schnell, E; Stöllberger, C; Fheodoroff, K; Seiser, A

    2001-05-01

    It is unclear if the severity of cardiac involvement in patients with myotonic dystrophy (MD) is related to the size of the CTG-repeat expansion. This open, uncontrolled, observational, prospective study aimed to find out if there is a relation between the severity of cardiac involvement in MD and the CTG-repeat size. In 21 patients with MD, (8 women, 13 men, aged 11-88 years) a detailed cardiologic examination, including history, clinical examination, electrocardiography (ECG), transthoracic echocardiography and ambulatory 24-h ECG, was carried out and cardiac involvement was assessed according to a previously described scoring system. Additionally, the CTG-repeat size was determined from nuclear DNA of blood leukocytes. The correlation between the CTG-repeat size and the mean heart rate, PQ-interval, QTc-interval, fractional shortening, left ventricular enddiastolic diameter, septal thickness, posterior wall thickness, mean heart rate on 24-h ECG and cardiac involvement score was r=0.47, r=0.086, r=0.11, r=-0.27, r=-0.34, r=-0.06, r=-0.12, r=0.16 and r=0.09 (all p>0.05), respectively. In patients 21-30, 31-40 and 41-50 years of age, cardiac involvement increased with increasing CTG-repeat size. In younger patients, the number of CTG-repeats needed to develop a reasonable cardiac involvement was higher than in older patients. Depending on age, cardiac involvement increases with increasing CTG-repeat size obtained from blood leukocytes in patients with MD.

  3. Ivabradine prolongs phase 3 of cardiac repolarization and blocks the hERG1 (KCNH2) current over a concentration-range overlapping with that required to block HCN4.

    Science.gov (United States)

    Lees-Miller, James P; Guo, Jiqing; Wang, Yibo; Perissinotti, Laura L; Noskov, Sergei Y; Duff, Henry J

    2015-08-01

    In Europe, ivabradine has recently been approved to treat patients with angina who have intolerance to beta blockers and/or heart failure. Ivabradine is considered to act specifically on the sinoatrial node by inhibiting the If current (the funny current) to slow automaticity. However, in vitro studies show that ivabradine prolongs phase 3 repolarization in ventricular tissue. No episodes of Torsades de Pointes have been reported in randomized clinical studies. The objective of this study is to assess whether ivabradine blocked the hERG1 current. In the present study we discovered that ivabradine prolongs action potential and blocks the hERG current over a range of concentrations overlapping with those required to block HCN4. Ivabradine produced tonic, rather than use-dependent block. The mutation Y652A significantly suppressed pharmacologic block of hERG by ivabradine. Disruption of C-type inactivation also suppressed block of hERG1 by ivabradine. Molecular docking and molecular dynamics simulations indicate that ivabradine may access the inner cavity of the hERG1 via a lipophilic route and has a well-defined binding site in the closed state of the channel. Structural organization of the binding pockets for ivabradine is discussed. Ivabradine blocks hERG and prolongs action potential duration. Our study is potentially important because it indicates the need for active post marketing surveillance of ivabradine. Importantly, proarrhythmia of a number of other drugs has only been discovered during post marketing surveillance.

  4. Grand rounds from international lupus centres cardiac abnormalities in SLE : pancarditis

    NARCIS (Netherlands)

    Bijl, M; Brouwer, J; Kallenberg, GGM

    2000-01-01

    Many patients with systemic lupus erythematosus (SLE) develop cardiac manifestations during the course of their disease. Pericarditis is most commonly seen, with a reported prevalence of 60%. Myocardial involvement is present in only a minority of patients. In recent years, due to better noninvasive

  5. Cardiac abnormalities assessed by non-invasive techniques in patients with newly diagnosed idiopathic inflammatory myopathies

    DEFF Research Database (Denmark)

    Diederichsen, Louise Pyndt; Simonsen, Jane Angel; Diederichsen, Axel Cosmus Pyndt

    2015-01-01

    inflammatory myopathies (IIM) by means of non-invasive techniques. METHODS: Fourteen patients with IIM (8 polymyositis, 4 dermatomyositis, 2 cancer-associated dermatomyositis) and 14 gender- and age- matched healthy control subjects were investigated. Participant assessments included a cardiac questionnaire...

  6. Congenital left ventricular wall abnormalities in adults detected by gated cardiac multidetector computed tomography: Clefts, aneurysms, diverticula and terminology problems

    Energy Technology Data Exchange (ETDEWEB)

    Erol, Cengiz, E-mail: drcengizerol@yahoo.com [Selcuk University, Selcuklu Faculty of Medicine, Department of Radiology, Alaeddin Keykubat Central Campus, Selcuklu, 42250 Konya (Turkey); Koplay, Mustafa, E-mail: koplaymustafa@hotmail.com [Selcuk University, Selcuklu Faculty of Medicine, Department of Radiology, Alaeddin Keykubat Central Campus, Selcuklu, 42250 Konya (Turkey); Olcay, Ayhan, E-mail: drayhanolcay@gmail.com [29 May Hospital, Department of Cardiology, Vatan Street, Fatih, 34150 Istanbul (Turkey); Kivrak, Ali Sami, E-mail: alisamikivrak@hotmail.com [Selcuk University, Selcuklu Faculty of Medicine, Department of Radiology, Alaeddin Keykubat Central Campus, Selcuklu, 42250 Konya (Turkey); Ozbek, Seda, E-mail: dsadr@hotmail.com [Selcuk University, Selcuklu Faculty of Medicine, Department of Radiology, Alaeddin Keykubat Central Campus, Selcuklu, 42250 Konya (Turkey); Seker, Mehmet, E-mail: hikmet.irfan@hotmail.com [29 May Hospital, Department of Radiology, Vatan Street, Fatih, 34150 Istanbul (Turkey); Paksoy, Yahya, E-mail: yahyapaksoy@yahoo.com [Selcuk University, Selcuklu Faculty of Medicine, Department of Radiology, Alaeddin Keykubat Central Campus, Selcuklu, 42250 Konya (Turkey)

    2012-11-15

    Objectives: Our aim was to evaluate congenital left ventricular wall abnormalities (clefts, aneurysms and diverticula), describe and illustrate imaging features, discuss terminology problems and determine their prevalence detected by cardiac CT in a single center. Materials and methods: Coronary CT angiography images of 2093 adult patients were evaluated retrospectively in order to determine congenital left ventricular wall abnormalities. Results: The incidence of left ventricular clefts (LVC) was 6.7% (141 patients) and statistically significant difference was not detected between the sexes regarding LVC (P = 0.5). LVCs were single in 65.2% and multiple in 34.8% of patients. They were located at the basal to mid inferoseptal segment of the left ventricle in 55.4%, the basal to mid anteroseptal segment in 24.1%, basal to mid inferior segment in 17% and septal-apical septal segment in 3.5% of cases. The cleft length ranged from 5 to 22 mm (mean 10.5 mm) and they had a narrow connection with the left ventricle (mean 2.5 mm). They were contractile with the left ventricle and obliterated during systole. Congenital left ventricular septal aneurysm that was located just under the aortic valve was detected in two patients (0.1%). No case of congenital left ventricular diverticulum was detected. Conclusion: Cardiac CT allows us to recognize congenital left ventricular wall abnormalities which have been previously overlooked in adults. LVC is a congenital structural variant of the myocardium, is seen more frequently than previously reported and should be differentiated from aneurysm and diverticulum for possible catastrophic complications of the latter two.

  7. Right ventricular arrhythmogenesis in failing human heart: the role of conduction and repolarization remodeling

    Science.gov (United States)

    Lou, Qing; Janks, Deborah L.; Holzem, Katherine M.; Lang, Di; Onal, Birce; Ambrosi, Christina M.; Fedorov, Vadim V.; Wang, I-Wen

    2012-01-01

    Increased dispersion of repolarization has been suggested to underlie increased arrhythmogenesis in human heart failure (HF). However, no detailed repolarization mapping data were available to support the presence of increased dispersion of repolarization in failing human heart. In the present study, we aimed to determine the existence of enhanced repolarization dispersion in the right ventricular (RV) endocardium from failing human heart and examine its association with arrhythmia inducibility. RV free wall preparations were dissected from five failing and five nonfailing human hearts, cannulated and coronary perfused. RV endocardium was optically mapped from an ∼6.3 × 6.3 cm2 field of view. Action potential duration (APD), dispersion of APD, and conduction velocity (CV) were quantified for basic cycle lengths (BCL) ranging from 2,000 ms to the functional refractory period. We found that RV APD was significantly prolonged within the failing group compared with the nonfailing group (560 ± 44 vs. 448 ± 39 ms, at BCL = 2,000 ms, P < 0.05). Dispersion of APD was increased in three failing hearts (161 ± 5 vs. 86 ± 19 ms, at BCL = 2,000 ms). APD alternans were induced by rapid pacing in these same three failing hearts. CV was significantly reduced in the failing group compared with the nonfailing group (81 ± 11 vs. 98 ± 8 cm/s, at BCL = 2,000 ms). Arrhythmias could be induced in two failing hearts exhibiting an abnormally steep CV restitution and increased dispersion of repolarization due to APD alternans. Dispersion of repolarization is enhanced across the RV endocardium in the failing human heart. This dispersion, together with APD alternans and abnormal CV restitution, could be responsible for the arrhythmia susceptibility in human HF. PMID:23042951

  8. Early repolarization electrocardiography pattern with unexplained syncope during training in a young black African non-elite athlete: an accidental finding?

    Science.gov (United States)

    Bonny, Aimé; Ditah, Ivo; Amara, Walid; Hamdaoui, Brahim; Frank, Robert; Le Heuzey, Jean-Yves

    2009-01-01

    Until recently it was generally thought that early repolarization is benign. But a recent article in the NEJM (Haissaguerre et al.) suggests that some persons with early repolarization may be at risk of life-threatening ventricular tachyarrhythmia. Unexplained syncope or sudden death occurs mostly during sleep. However, some cases of cardiac arrest during exertion have been reported. We report the case of a 39 year-old black African male with early repolarization pattern on electrocardiogram who regularly experienced dizziness (and one episode of transient loss of consciousness) exclusively while exercising. Detailed examination was normal. Under quinidine therapy, he experienced no further episodes. Increasingly reported cases of cardiac arrest in Africans, and significant prevalence of early repolarization in this population, have to be taken into account since the Haissaguerre et al. report. Further evidence of the lethal consequences of this syndrome are needed, bearing in mind that diagnostic tools for life-threatening arrhythmias are often scarce in sub-Saharan Africa.

  9. Myocyte repolarization modulates myocardial function in aging dogs.

    Science.gov (United States)

    Sorrentino, Andrea; Signore, Sergio; Qanud, Khaled; Borghetti, Giulia; Meo, Marianna; Cannata, Antonio; Zhou, Yu; Wybieralska, Ewa; Luciani, Marco; Kannappan, Ramaswamy; Zhang, Eric; Matsuda, Alex; Webster, Andrew; Cimini, Maria; Kertowidjojo, Elizabeth; D'Alessandro, David A; Wunimenghe, Oriyanhan; Michler, Robert E; Royer, Christopher; Goichberg, Polina; Leri, Annarosa; Barrett, Edward G; Anversa, Piero; Hintze, Thomas H; Rota, Marcello

    2016-04-01

    Studies of myocardial aging are complex and the mechanisms involved in the deterioration of ventricular performance and decreased functional reserve of the old heart remain to be properly defined. We have studied a colony of beagle dogs from 3 to 14 yr of age kept under a highly regulated environment to define the effects of aging on the myocardium. Ventricular, myocardial, and myocyte function, together with anatomical and structural properties of the organ and cardiomyocytes, were evaluated. Ventricular hypertrophy was not observed with aging and the structural composition of the myocardium was modestly affected. Alterations in the myocyte compartment were identified in aged dogs, and these factors negatively interfere with the contractile reserve typical of the young heart. The duration of the action potential is prolonged in old cardiomyocytes contributing to the slower electrical recovery of the myocardium. Also, the remodeled repolarization of cardiomyocytes with aging provides inotropic support to the senescent muscle but compromises its contractile reserve, rendering the old heart ineffective under conditions of high hemodynamic demand. The defects in the electrical and mechanical properties of cardiomyocytes with aging suggest that this cell population is an important determinant of the cardiac senescent phenotype. Collectively, the delayed electrical repolarization of aging cardiomyocytes may be viewed as a critical variable of the aging myopathy and its propensity to evolve into ventricular decompensation under stressful conditions.

  10. Noninvasive imaging modalities and sudden cardiac arrest in the young: can they help distinguish subjects with a potentially life-threatening abnormality from normals?

    Science.gov (United States)

    Printz, Beth Feller

    2012-03-01

    Sudden cardiac arrest (SCA) in the young is always tragic, but fortunately it is an unusual event. When it does occur, it usually happens in active individuals, often while they are participating in physical activity. Depending on the population's characteristics, the most common causes of sudden cardiac arrest in these subjects are hypertrophic cardiomyopathy, congenital coronary abnormalities, arrhythmia in the presence of a structurally normal heart (ion channelopathies or abnormal conduction pathways), aortic rupture, and arrhythmogenic right-ventricular cardiomyopathy. Two-dimensional echocardiography (2-DE) has been proposed as a screening tool that can potentially detect four of these five causes of SCA, and many groups now sponsor community-based 2-DE SCA-screening programs. "Basic" 2-DE screening may include assessment of ventricular volumes, mass, and function; left atrial size; and cardiac and thoracic vascular (including coronary) anatomy. "Advanced" echocardiographic techniques, such as tissue Doppler and strain imaging, can help in diagnosis when the history, electrocardiogram (ECG), and/or standard 2-DE screening suggest there may be an abnormality, e.g., to help differentiate those with "athlete's heart" from hypertrophic or dilated cardiomyopathy. Cardiac magnetic resonance imaging or cardiac computed tomography can be added to increase diagnostic sensitivity and specificity in select cases when an abnormality is suggested during SCA screening. Test availability, cost, and ethical issues related to who to screen, as well as the detection of those with potential disease but low risk, must be balanced when deciding what tests to perform to assess for increased SCA risk.

  11. Chronic Omega-3 Polyunsaturated Fatty Acid Treatment Variably Affects Cellular Repolarization in a Healed Post-MI Arrhythmia Model

    Science.gov (United States)

    Bonilla, Ingrid M.; Nishijima, Yoshinori; Vargas-Pinto, Pedro; Baine, Stephen H.; Sridhar, Arun; Li, Chun; Billman, George E.; Carnes, Cynthia A.

    2016-01-01

    Introduction: Over the last 40 years omega-3 polyunsaturated fatty acids (PUFAs) have been shown to be anti-arrhythmic or pro-arrhythmic depending on the method and duration of administration and model studied. We previously reported that omega-3 PUFAs do not confer anti-arrhythmic properties and are pro-arrhythmic in canine model of sudden cardiac death (SCD). Here, we evaluated the effects of chronic omega-3 PUFA treatment in post-MI animals susceptible (VF+) or resistant (VF−) to ventricular tachyarrhythmias. Methods: Perforated patch clamp techniques were used to measure cardiomyocyte action potential durations (APD) at 50 and 90% repolarization and short term variability of repolarization. The early repolarizing transient outward potassium current Ito was also studied. Results: Omega-3 PUFAs prolonged the action potential in VF− myocytes at both 50 and 90% repolarization. Short term variability of repolarization was increased in both untreated and treated VF− myocytes vs. controls. Ito was unaffected by omega-3 PUFA treatment. Omega-3 PUFA treatment attenuated the action potential prolongation in VF+ myocytes, but did not return repolarization to control values. Conclusions: Omega-3 PUFAs do not confer anti-arrhythmic properties in the setting of healed myocardial infarction in a canine model of SCD. In canines previously resistant to ventricular fibrillation (VF−), omega-3 PUFA treatment prolonged the action potential in VF− myocytes, and may contribute to pro-arrhythmic responses. PMID:27378936

  12. Next-generation sequencing of 100 candidate genes in young victims of suspected sudden cardiac death with structural abnormalities of the heart

    DEFF Research Database (Denmark)

    Hertz, C L; Christiansen, S L; Ferrero-Miliani, Laura;

    2016-01-01

    BACKGROUND: In sudden, unexpected, non-traumatic death in young individuals, structural abnormalities of the heart are frequently identified at autopsy. However, the findings may be unspecific and cause of death may remain unclear. A significant proportion of these cases are most likely caused...... by inherited cardiac diseases, and the cases are categorized as sudden cardiac death (SCD). The purpose of this study was to explore the added diagnostic value of genetic testing by next-generation sequencing (NGS) of a broad gene panel, as a supplement to the traditional forensic investigation in cases...... with non-diagnostic structural abnormalities of the heart. METHODS AND RESULTS: We screened 72 suspected SCD cases (

  13. A dual potassium channel activator improves repolarization reserve and normalizes ventricular action potentials

    DEFF Research Database (Denmark)

    Calloe, Kirstine; Di Diego, José M; Hansen, Rie Schultz

    2016-01-01

    in cultured canine cardiac myocytes and determined whether a dual K(+) current activator can normalize K(+) currents and restore action potential (AP) configuration. METHODS AND RESULTS: Ventricular myocytes were isolated and cultured for up to 48h. Current and voltage clamp recordings were made using patch...... of EADs. Our results suggest a potential benefit of K(+) current activators under conditions of reduced repolarization reserve including heart failure....

  14. Abnormal uptake of technetium-99m hexakis-2-methoxyisobutylisonitrile in a primary cardiac lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Medolago, G.; Virotta, G.; Bertocchi, C. (Ospedali Riuniti di Bergamo (Italy). Dept. of Nuclear Medicine); Piti, A.; Tespili, M.; D' Adda, F. (Ospedali Riuniti di Bergamo (Italy). Dept. of Cardiology); Rottoli, M.R. (Ospedali Riuniti di Bergamo (Italy). Dept. of Neurology); Comotti, B. (Ospedali Riuniti di Bergamo (Italy). Dept. of Hematology); Motta, T. (Ospedali Riuniti di Bergamo (Italy). Dept. of Pathology); Orlandi, C. (Du Pont Pharma, North Billerica, MA (United States))

    1992-03-01

    Abnormally high uptake of technetium-99m hexakis-2-methoxyisobutylisonitrile ({sup 99m}Tc-SESTAMIBI) in the right ventricle and in the septum was observed in a 47-year-old woman initially presenting with dysarthria and left hemiparesis. Endomyocardial biopsy demonstrated a high-grade malignant non-Hodgkin's lymphoma. Complete remission was achieved by combined cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) chemotherpay and radiotherapy of the heart and mediastinum. The post-remission single photon emission tomography (SPET) {sup 99m}Tc-SESTAMIBI study showed a homogeneous distribution pattern, in agreement with echocardiography computed tomography and magnetic resonance imaging. Increased uptake of {sup 99m}Tc-SESTAMIBI, a myocardial perfusion agent, has been observed in some benign and malignant tumours. It may prove to be useful in the diagnosis and follow-up of malignancies. (orig.).

  15. Effects of Na+ channel blockers on extrasystolic stimulation-evoked changes in ventricular conduction and repolarization.

    Science.gov (United States)

    Osadchii, Oleg E

    2014-03-01

    Antiarrhythmic agents which belong to class Ia (quinidine) and Ic (flecainide) reportedly increase propensity to ventricular tachyarrhythmia, whereas class Ib agents (lidocaine and mexiletine) are recognized as safe antiarrhythmics. Clinically, tachyarrhythmia is often initiated by a premature ectopic beat, which increases spatial nonuniformities in ventricular conduction and repolarization thus facilitating reentry. This study examined if electrical derangements evoked by premature excitation may be accentuated by flecainide and quinidine, but unchanged by lidocaine and mexiletine, which would explain the difference in their safety profile. In perfused guinea pig hearts, a premature excitation evoked over late repolarization phase was associated with prolonged epicardial activation time, reduced monophasic action potential duration (APD), and increased transepicardial dispersion of the activation time and APD. Flecainide and quinidine increased conduction slowing evoked by extrasystolic stimulation, prolonged APD, and accentuated spatial heterogeneities in ventricular conduction and repolarization associated with premature excitation. Spontaneous episodes of nonsustained monomorphic ventricular tachycardia were observed in 50% of heart preparations exposed to drug infusion. In contrast, lidocaine and mexiletine had no effect on extrasystolic stimulation-evoked changes in ventricular conduction and repolarization or arrhythmic susceptibility. These findings suggest that flecainide and quinidine may promote arrhythmia by exaggerating electrophysiological abnormalities evoked by ectopic beats.

  16. Cardiac abnormalities in diabetic patients with mutation in the mitochondrial tRNA {sup Leu(UUR)}Gene

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Hiroshi [Hyogo Medical Center for Adults, Akashi (Japan); Shiotani, Hideyuki

    1999-11-01

    An A-to-G transition at position 3243 of the mitochondrial DNA is known to be a pathogenic factor for mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes (MELAS), diabetes and cardiomyopathy. This mutation causes dysfunction of the central nervous system in MELAS. Because the heart, as well as the brain and nervous system, is highly dependent on the energy produced by mitochondrial oxidation, these tissues are more vulnerable to mitochondrial defects. Cardiac abnormalities were assessed in 10 diabetic patients associated with this mutation using echocardiography and {sup 123}I-metaiodobenzylguanidine (MIBG) scintigraphy, and compared with 19 diabetic patients without the mutation. Duration of diabetes, therapy, control of blood glucose and diabetic complications, such as diabetic retinopathy and nephropathy, were not different between the 2 groups. Diabetic patients with the mutation had a significantly thicker interventricular septum (16.8{+-}3.7 vs 11.0{+-}1.6 mm, p<0.001) than those without the mutation. Fractional shortening was lower in diabetic patients with the mutation than those without it (30.7{+-}7.0 vs 42.5{+-}6.6, p<0.001). MIBG uptake on the delayed MIBG image was significantly lower in diabetic patients with the mutation than in those without the mutation (mean value of the heart to mediastinum ratio: 1.6{+-}0.2 vs 2.0{+-}0.4, p>0.05). In conclusion, left ventricular hypertrophy with or without abnormal wall motion and severely reduced MIBG uptake may be characteristic in diabetic patients with a mutation in the mitochondrial tRNA {sup Leu(UUR)} gene. (author)

  17. Pharmacological inhibition of I-K1 by PA-6 in isolated rat hearts affects ventricular repolarization and refractoriness

    DEFF Research Database (Denmark)

    Skarsfeldt, Mark A.; Carstensen, Helena; Skibsbye, Lasse

    2016-01-01

    The inwardly rectifying potassium current (IK1) conducted through Kir2.X channels contribute to repolarization of the cardiac action potential and to stabilization of the resting membrane potential in cardiomyocytes. Our aim was to investigate the effect of the recently discovered IK1 inhibitor PA......-6 on action potential repolarization and refractoriness in isolated rat hearts. Transiently transfected HEK-293 cells expressing IK1 were voltage-clamped with ramp protocols. Langendorff-perfused heart experiments were performed on male Sprague–Dawley rats, effective refractory period, Wenckebach...... experiments, PA-6 prolonged the ventricular action potential duration at 90% repolarization (from 41.8 6.5 msec to 72.6 21.1 msec, 74% compared to baseline, P

  18. Diabetes mellitus and sudden cardiac death: what are the data?

    Science.gov (United States)

    Bergner, Daniel W; Goldberger, Jeffrey J

    2010-01-01

    Diabetes mellitus has long been linked to an increased risk of sudden cardiac death. However, the magnitude of this association, and the mechanism accounting for this phenomenon, have not been precisely defined. In this review, we evaluate the epidemiological data pertaining to the association between diabetes mellitus and sudden cardiac death and discuss various proposed mechanisms that may account for this relationship. Potential factors contributing to the increased risk of sudden cardiac death observed in patients with diabetes mellitus include silent myocardial ischemia, autonomic nervous system dysfunction, abnormal cardiac repolarization, hypoglycemia, a hypercoaguable state secondary to diabetes mellitus, diabetic cardiomyopathy, and impaired respiratory response to hypoxia and hypercapnea. We conclude that diabetes mellitus does appear to be associated with an increased risk of sudden cardiac death. Although this increased risk is relatively modest, given the large number of diabetic patients worldwide, the absolute number of sudden cardiac deaths attributable to diabetes mellitus remains significant. Little evidence exists to support any specific mechanism(s) accounting for this association. Further investigation into the pathophysiology of sudden cardiac death in diabetes mellitus may yield improved risk stratification tools as well as identify novel therapeutic targets.

  19. Cardiac abnormalities in the acquired immunodeficiency syndrome. A prospective study with a clinical-pathological correlation in twenty-one adult patients

    Directory of Open Access Journals (Sweden)

    Herdy Gesmar Volga Haddad

    1999-01-01

    Full Text Available OBJECTIVE - To evaluate the cardiac abnormalities and their evolution during the course of the acquired immunodeficiency syndrome, as well as to correlate clinical and pathological data. METHODS - Twenty-one patients, admitted to the hospital with the diagnosis of acquired immunodeficiency syndrome, were prospectively studied and followed until their death. Age ranged from 19 to 42 years (17 males. ECG and echocardiogram were also obtained every six months. After death, macro- and microscopic examinations were also performed. RESULTS - The most frequent causes of referral to the hospital were: diarrhea or repeated pneumonias, tuberculosis, toxoplasmosis or Kaposi sarcoma. The most frequent findings were acute or chronic pericarditis (42% and dilated cardiomyopathy (19%. Four patients died of cardiac problems: infective endocarditis, pericarditis with pericardial effusion, bacterial myocarditis and infection by Toxoplasma gondii. CONCLUSION - Severe cardiac abnormalities were the cause of death in some patients. In the majority of the patients, a good correlation existed between clinical and anatomical-pathological data. Cardiac evaluation was important to detect early manifestations and treat them accordingly, even in asymptomatic patients.

  20. AKAP13 Rho-GEF and PKD-binding domain deficient mice develop normally but have an abnormal response to β-adrenergic-induced cardiac hypertrophy.

    Directory of Open Access Journals (Sweden)

    Matthew J Spindler

    Full Text Available BACKGROUND: A-kinase anchoring proteins (AKAPs are scaffolding molecules that coordinate and integrate G-protein signaling events to regulate development, physiology, and disease. One family member, AKAP13, encodes for multiple protein isoforms that contain binding sites for protein kinase A (PKA and D (PKD and an active Rho-guanine nucleotide exchange factor (Rho-GEF domain. In mice, AKAP13 is required for development as null embryos die by embryonic day 10.5 with cardiovascular phenotypes. Additionally, the AKAP13 Rho-GEF and PKD-binding domains mediate cardiomyocyte hypertrophy in cell culture. However, the requirements for the Rho-GEF and PKD-binding domains during development and cardiac hypertrophy are unknown. METHODOLOGY/PRINCIPAL FINDINGS: To determine if these AKAP13 protein domains are required for development, we used gene-trap events to create mutant mice that lacked the Rho-GEF and/or the protein kinase D-binding domains. Surprisingly, heterozygous matings produced mutant mice at Mendelian ratios that had normal viability and fertility. The adult mutant mice also had normal cardiac structure and electrocardiograms. To determine the role of these domains during β-adrenergic-induced cardiac hypertrophy, we stressed the mice with isoproterenol. We found that heart size was increased similarly in mice lacking the Rho-GEF and PKD-binding domains and wild-type controls. However, the mutant hearts had abnormal cardiac contractility as measured by fractional shortening and ejection fraction. CONCLUSIONS: These results indicate that the Rho-GEF and PKD-binding domains of AKAP13 are not required for mouse development, normal cardiac architecture, or β-adrenergic-induced cardiac hypertrophic remodeling. However, these domains regulate aspects of β-adrenergic-induced cardiac hypertrophy.

  1. The evaluation of a new marker of transmyocardial repolarization parameters in ischemic stroke patients; T peak-T end (T p-e), T p-e/QTc.

    Science.gov (United States)

    Emektar, Emine; Çorbacıoğlu, Şeref Kerem; Korucu, Osman; Ramadan, Selma; Uzunosmanoğlu, Hüseyin; Kan, Eda; Çevik, Yunsur

    2017-01-21

    The cardiovascular manifestations of acute ischemic stroke have been well known. Several electrocardiography (ECG) abnormalities have been reported in patients following acute stroke, including QT interval prolongation, ST segment deviation and T-wave changes. This study aimed to investigate the changes in transmyocardial repolarization parameters, in ischemic stroke patients. The study is a prospective, blind, and controlled clinical study. The patients without cardiac disease who received ischemic stroke diagnoses were included in the study. ECG was received from the patients in the first hour and 72 h. The P, QT, T p-e, T p-e dispersion, and the T p-e/QT ratio were calculated. Moreover, fifty-five stroke patients and 35 control subjects were included to the study. All dispersion values and T p-e/QTc ratio in patients group were higher than those of control group (p e/QTc ratio in ECGs on third day than ECGs on first day (p e dispersions values in patients who have insular lobe involvement were higher than those of patients who do not have insular lobe involvement (p e and T p-e/QTc, during first 24 and 72 h in acute stroke patients without cardiovascular disease compared with the control group. The physicians should be aware about ventricular dysrhythmias in patients with ischemic stroke and these patients closely observed with cardiac monitoring, especially within first 24 h, and especially patients with insular lobe involvement.

  2. Impact of hypokalemia on electromechanical window, excitation wavelength and repolarization gradients in guinea-pig and rabbit hearts.

    Directory of Open Access Journals (Sweden)

    Oleg E Osadchii

    Full Text Available Normal hearts exhibit a positive time difference between the end of ventricular contraction and the end of QT interval, which is referred to as the electromechanical (EM window. Drug-induced prolongation of repolarization may lead to the negative EM window, which was proposed to be a novel proarrhythmic marker. This study examined whether abnormal changes in the EM window may account for arrhythmogenic effects produced by hypokalemia. Left ventricular pressure, electrocardiogram, and epicardial monophasic action potentials were recorded in perfused hearts from guinea-pig and rabbit. Hypokalemia (2.5 mM K(+ was found to prolong repolarization, reduce the EM window, and promote tachyarrhythmia. Nevertheless, during both regular pacing and extrasystolic excitation, the increased QT interval invariably remained shorter than the duration of mechanical systole, thus yielding positive EM window values. Hypokalemia-induced arrhythmogenicity was associated with slowed ventricular conduction, and shortened effective refractory periods, which translated to a reduced excitation wavelength index. Hypokalemia also evoked non-uniform prolongation of action potential duration in distinct epicardial regions, which resulted in increased spatial variability in the repolarization time. These findings suggest that arrhythmogenic effects of hypokalemia are not accounted for by the negative EM window, and are rather attributed to abnormal changes in ventricular conduction times, refractoriness, excitation wavelength, and spatial repolarization gradients.

  3. Impact of hypokalemia on electromechanical window, excitation wavelength and repolarization gradients in guinea-pig and rabbit hearts.

    Science.gov (United States)

    Osadchii, Oleg E

    2014-01-01

    Normal hearts exhibit a positive time difference between the end of ventricular contraction and the end of QT interval, which is referred to as the electromechanical (EM) window. Drug-induced prolongation of repolarization may lead to the negative EM window, which was proposed to be a novel proarrhythmic marker. This study examined whether abnormal changes in the EM window may account for arrhythmogenic effects produced by hypokalemia. Left ventricular pressure, electrocardiogram, and epicardial monophasic action potentials were recorded in perfused hearts from guinea-pig and rabbit. Hypokalemia (2.5 mM K(+)) was found to prolong repolarization, reduce the EM window, and promote tachyarrhythmia. Nevertheless, during both regular pacing and extrasystolic excitation, the increased QT interval invariably remained shorter than the duration of mechanical systole, thus yielding positive EM window values. Hypokalemia-induced arrhythmogenicity was associated with slowed ventricular conduction, and shortened effective refractory periods, which translated to a reduced excitation wavelength index. Hypokalemia also evoked non-uniform prolongation of action potential duration in distinct epicardial regions, which resulted in increased spatial variability in the repolarization time. These findings suggest that arrhythmogenic effects of hypokalemia are not accounted for by the negative EM window, and are rather attributed to abnormal changes in ventricular conduction times, refractoriness, excitation wavelength, and spatial repolarization gradients.

  4. Low-dose carvedilol reduces transmural heterogeneity of ventricular repolarization in congestive heart failure

    Institute of Scientific and Technical Information of China (English)

    Jiang-hua ZHONG; Xiao-pan CHEN; Mei-ling YUN; Wei-jing LI; Yan-fang CHEN; Zhen YAO

    2007-01-01

    Aim: To study the effects of carvedilol on the transmural heterogeneity of ven-tricular repolarization in rabbits with congestive heart failure (CHF). Methods:Rabbits were randomly divided into 3 groups: control, CHF and carvedilol treated CHF group. Monophasic action potential duration (MAPD) in the 3 myocardial layers was simultaneously recorded. Results: All the rabbits in the CHF group had signs of severe CHF. Compared with the control group, the mean blood pressure and cardiac output were significantly decreased, while peripheral resis-tance was significantly increased in the CHF group. This proved that the CHF model was successful created with adriamycin in this study. Compared to the control group, the ventricular fibrillation threshold (VFT) was remarkably decreased and all MAPD of the 3 myocardial layers were extended in rabbits with CHF. However, the extension of MAPD in the midmyocardium was more obvious. The transmural dispersion of repolarization (TDR) was significantly increased in CHF.Low-dose carvedilol (0.25 mg/kg, twice daily) had no effects on ventricular remodeling. Treatment with low-dose carvedilol significantly increased VFT. Al-though the MAPD of the 3 myocardial layers were further prolonged in the carvedilol treated CHF group, the prolongation of MAPD in the midmyocardium was shorter than those in the epicardium and endocardium. Treatment with low-dose carvedilol significantly decreased TDR in CHF. Conclusion: In the present study, the trans-mural heterogeneity of ventricular repolarization increased in the rabbits with CHF. Low-dose carvedilol decreased the transmural heterogeneity of ventricular repolarization in CHF, which may be related to its direct electrophysiological pro-perty rather than its effect on ventricular remodeling.

  5. Cardiac electrical defects in progeroid mice and Hutchinson–Gilford progeria syndrome patients with nuclear lamina alterations

    Science.gov (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

    2016-01-01

    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

  6. Risk of cardiac arrhythmias during hypoglycemia in patients with type 2 diabetes and cardiovascular risk.

    Science.gov (United States)

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

    2014-05-01

    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.

  7. Heart rate profile during exercise in patients with early repolarization

    Institute of Scientific and Technical Information of China (English)

    Serkan Cay; Goksel Cagirci; Ramazan Atak; Yucel Balbay; Ahmet Duran Demir; Sinan Aydogdu

    2010-01-01

    Background Both early repolarization and altered heart rate profile are associated with sudden death. In this study, we aimed to demonstrate an association between early repolarization and heart rate profile during exercise.Methods A total of 84 subjects were included in the study. Comparable 44 subjects with early repolarization and 40 subjects with normal electrocardiogram underwent exercise stress testing. Resting heart rate, maximum heart rate, heart rate increment and decrement were analyzed.Results Both groups were comparable for baseline characteristics including resting heart rate. Maximum heart rate, heart rate increment and heart rate decrment of the subjects in early repolarization group had significantly decreased maximum heart rate, heart rate increment and heart rate decrement compared to control group (all P<0.05). The lower heart rate increment (<106 beats/min) and heart rate decrement (<95 beats/min) were significantly associated with the presence of early repolarization. After adjustment for age and sex, the multiple-adjusted OR of the risk of presence of early repolarization was 2.98 (95% CI 1.21-7.34) (P=0.018) and 7.73 (95% CI 2.84-21.03) (P <0.001) for the lower heart rate increment and heart rate decrement compared to higher levels, respectively.Conclusions Subjects with early repolarization have altered heart rate profile during exercise compared to control subjects. This can be related to sudden death.

  8. Abnormal splicing in the N-terminal variable region of cardiac troponin T impairs systolic function of the heart with preserved Frank-Starling compensation.

    Science.gov (United States)

    Feng, Han-Zhong; Chen, Guozhen; Nan, Changlong; Huang, Xupei; Jin, Jian-Ping

    2014-09-01

    Abnormal splice-out of the exon 7-encoded segment in the N-terminal variable region of cardiac troponin T (cTnT-ΔE7) was found in turkeys and, together with the inclusion of embryonic exon (eTnT), in adult dogs with a correlation with dilated cardiomyopathy. Overexpression of these cTnT variants in transgenic mouse hearts significantly decreased cardiac function. To further investigate the functional effect of cTnT-ΔE7 or ΔE7+eTnT in vivo under systemic regulation, echocardiography was carried out in single and double-transgenic mice. No atrial enlargement, ventricular hypertrophy or dilation was detected in the hearts of 2-month-old cTnT-ΔE7 and ΔE7+eTnT mice in comparison to wild-type controls, indicating a compensated state. However, left ventricular fractional shortening and ejection fraction were decreased in ΔE7 and ΔE7+eTnT mice, and the response to isoproterenol was lower in ΔE7+eTnT mice. Left ventricular outflow tract velocity and gradient were decreased in the transgenic mouse hearts, indicating decreased systolic function. Ex vivo working heart function showed that high afterload or low preload resulted in more severe decreases in the systolic function and energetic efficiency of cTnT-ΔE7 and ΔE7+eTnT hearts. On the other hand, increases in preload demonstrated preserved Frank-Starling responses and minimized the loss of cardiac function and efficiency. The data demonstrate that the N-terminal variable region of cardiac TnT regulates systolic function of the heart.

  9. High fat diet enhances cardiac abnormalities in SHR rats: Protective role of heme oxygenase-adiponectin axis

    Directory of Open Access Journals (Sweden)

    Cao Jian

    2011-12-01

    Full Text Available Abstract Background High dietary fat intake is a major risk factor for development of cardiovascular and metabolic dysfunction including obesity, cardiomyopathy and hypertension. Methods The present study was designed to examine effect of high fat (HF diet on cardio-vascular structure and function in spontaneously hypertensive rats (SHR, fed HF diet for 15 weeks, a phenotype designed to mimic metabolic syndrome. Results Development of metabolic syndrome like phenotype was confirmed using parameters, including body weight, total cholesterol and blood pressure levels. High fat diet impaired vascular relaxation by acetylcholine and exacerbated cardiac dysfunction in SHRs as evidenced by lower left ventricular function, and higher coronary resistance (CR as compared to controls (p 2- levels in SHR fed a HF diet (p Conclusion In conclusion, this novel study demonstrates that up-regulation of HO-1 improves cardiac and vascular dysfunction by blunting oxidative stress, COX-2 levels and increasing adiponectin levels in hypertensive rats on HF diet.

  10. Temporal complexity of repolarization and mortality in patients with implantable cardioverter defibrillators.

    Science.gov (United States)

    Perkiomaki, Juha S; Couderc, Jean-Philippe; Daubert, James P; Zareba, Wojciech

    2003-10-01

    Increased repolarization variability has been observed in various cardiac conditions. However, data on its relation to heart rate variability and on its value in predicting adverse outcomes in high risk patients are limited. Forty-seven patients with decreased left ventricular function and ICDs had high resolution 10-minute ECG recordings and were followed for 781 +/- 258 days (mean +/- SD) on average. The interval from the R peak to the T wave peak with maximum amplitude (RTmax) and from the R peak to the T wave offset (RToff) were determined automatically on a beat-to-beat basis. Temporal beat-to-beat RTmax and RToff variability were analyzed using traditional summary statistics, a complexity measure (approximate entropy [ApEn]), and the short-term scaling exponent (alpha1). Eight (17%) patients died and 16 (34%) patients experienced death/appropriate ICD shock during follow-up. RTmax-ApEn was significantly higher in patients who died compared with patients who survived (1.24 +/- 0.13 vs 1.01 +/- 0.21, respectively, P=0.008). When RTmax-ApEn was tested together with the alpha1 of the RR intervals, occurrence of ventricular arrhythmias before ICD implantation, and beta-blockers usage in the Cox regression analysis, it still independently predicted mortality; hazard ratio=3.36 (1.28-8.83, 95% CI, P=0.014) for every 0.10-increase in RTmax-ApEn. None of the repolarization variability parameters independently predicted death/appropriate ICD shocks. Increased temporal complexity of repolarization (RTmax-ApEn) independently predicts mortality in ICD patients.

  11. Association of interatrial septal abnormalities with cardiac impulse conduction disorders in adult patients: experience from a tertiary center in Kosovo.

    Directory of Open Access Journals (Sweden)

    Zaim Gashi

    2011-06-01

    Full Text Available Interatrial septal disorders, which include: atrial septal defect, patent foramen ovale and atrial septal aneurysm, are frequent congenital anomalies found in adult patients. Early detection of these anomalies is important to prevent their hemodynamic and/or thromboembolic consequences. The aims of this study were: to assess the association between impulse conduction disorders and anomalies of interatrial septum; to determine the prevalence of different types of interatrial septum abnormalities; to assess anatomic, hemodynamic, and clinical consequences of interatrial septal pathologies. Fifty-three adult patients with impulse conduction disorders and patients without ECG changes but with signs of interatrial septal abnormalities, who were referred to our center for echocardiography, were included in a prospective transesophageal echocardiography study. Intera trial septal anomalies were detected in around 85% of the examined patients.

  12. Mathematical cardiac electrophysiology

    CERN Document Server

    Colli Franzone, Piero; Scacchi, Simone

    2014-01-01

    This book covers the main mathematical and numerical models in computational electrocardiology, ranging from microscopic membrane models of cardiac ionic channels to macroscopic bidomain, monodomain, eikonal models and cardiac source representations. These advanced multiscale and nonlinear models describe the cardiac bioelectrical activity from the cell level to the body surface and are employed in both the direct and inverse problems of electrocardiology. The book also covers advanced numerical techniques needed to efficiently carry out large-scale cardiac simulations, including time and space discretizations, decoupling and operator splitting techniques, parallel finite element solvers. These techniques are employed in 3D cardiac simulations illustrating the excitation mechanisms, the anisotropic effects on excitation and repolarization wavefronts, the morphology of electrograms in normal and pathological tissue and some reentry phenomena. The overall aim of the book is to present rigorously the mathematica...

  13. A class of Monte-Carlo-based statistical algorithms for efficient detection of repolarization alternans.

    Science.gov (United States)

    Iravanian, Shahriar; Kanu, Uche B; Christini, David J

    2012-07-01

    Cardiac repolarization alternans is an electrophysiologic condition identified by a beat-to-beat fluctuation in action potential waveform. It has been mechanistically linked to instances of T-wave alternans, a clinically defined ECG alternation in T-wave morphology, and associated with the onset of cardiac reentry and sudden cardiac death. Many alternans detection algorithms have been proposed in the past, but the majority have been designed specifically for use with T-wave alternans. Action potential duration (APD) signals obtained from experiments (especially those derived from optical mapping) possess unique characteristics, which requires the development and use of a more appropriate alternans detection method. In this paper, we present a new class of algorithms, based on the Monte Carlo method, for the detection and quantitative measurement of alternans. Specifically, we derive a set of algorithms (one an analytical and more efficient version of the other) and compare its performance with the standard spectral method and the generalized likelihood ratio test algorithm using synthetic APD sequences and optical mapping data obtained from an alternans control experiment. We demonstrate the benefits of the new algorithm in the presence of Gaussian and Laplacian noise and frame-shift errors. The proposed algorithms are well suited for experimental applications, and furthermore, have low complexity and are implementable using fixed-point arithmetic, enabling potential use with implantable cardiac devices.

  14. Cardiac Sarcoidosis.

    Science.gov (United States)

    Birnie, David; Ha, Andrew C T; Gula, Lorne J; Chakrabarti, Santabhanu; Beanlands, Rob S B; Nery, Pablo

    2015-12-01

    Studies suggest clinically manifest cardiac involvement occurs in 5% of patients with pulmonary/systemic sarcoidosis. The principal manifestations of cardiac sarcoidosis (CS) are conduction abnormalities, ventricular arrhythmias, and heart failure. Data indicate that an 20% to 25% of patients with pulmonary/systemic sarcoidosis have asymptomatic (clinically silent) cardiac involvement. An international guideline for the diagnosis and management of CS recommends that patients be screened for cardiac involvement. Most studies suggest a benign prognosis for patients with clinically silent CS. Immunosuppression therapy is advocated for clinically manifest CS. Device therapy, with implantable cardioverter defibrillators, is recommended for some patients.

  15. Minimizing repolarization-related proarrhythmic risk in drug development and clinical practice.

    Science.gov (United States)

    Farkas, Attila S; Nattel, Stanley

    2010-03-26

    Proarrhythmia, the development of new or worse arrhythmias in response to drug therapy, is a major limitation to the development and use of new drugs. There are different types of drug-induced proarrhythmia, including long-QT syndrome (LQTS), short-QT syndrome and proarrhythmia related to Na+-channel blockade/conduction impairment. By far the most important form of proarrhythmia at present is drug-induced LQTS and its associated characteristic tachyarrhythmia, torsades de pointes (TdP). TdP arises when cellular action potentials (APs) are excessively prolonged, leading to arrhythmogenic afterdepolarizations, especially early afterdepolarizations (EADs), which trigger complex re-entry in a substrate involving increased transmural dispersion of repolarization. In vitro screening, increasingly involving high-throughput assays, is used to assess potential candidate molecules and eliminate potentially problematic structures at an early stage of development. The most commonly used screening assays assess drug block of the K+ current carried by human ether-à-go-go (hERG) subunits, corresponding to the rapid delayed-rectifier K+ channel, the overwhelmingly most common target of TdP-inducing drugs. In addition, the effects of drugs on AP duration or the in vivo equivalent, QT interval, are often assessed in animal models. Methods available for repolarization-related proarrhythmic risk assessment include in vitro (Langendorff-perfused rabbit or guinea pig hearts) and in vivo models (such as alpha-adrenoceptor-stimulated rabbits, rabbits with reduced repolarization reserve due to block of slow delayed-rectifier current, animals with chronic atrioventricular block or animals with cardiac remodelling caused by congestive heart failure). In silico modelling may be helpful for molecular design of non-hERG blocking candidates and for optimization of compound selection (at the molecular and pharmacological profile levels). Finally, clinical evaluation of effects on

  16. Repolarization features as detectable from electrograms and electrocardiograms

    NARCIS (Netherlands)

    Oosterom, A. van

    2013-01-01

    This contribution discusses the feasibility of extracting the major features of repolarization: its spatio-temporal behaviour, and how much of its global or local behaviour might be deduced from signals that can be observed experimentally. The analysis presented is based on source-volume-conductor c

  17. The effects of sotalol on ventricular repolarization during exercise

    Institute of Scientific and Technical Information of China (English)

    LI Jian; WANG Jia-nan

    2005-01-01

    Objective: Although after pacing animal and human studies have demonstrated a rate-dependent effect of sotalol on ventricular repolarization, there is little information on the effects of sotalol on ventricular repolarization during exercise. This study attempted to show the effects of sotalol on ventricular repolarization during physiological exercise. Methods: Thirty-one healthy volunteers (18 males, 13 females) were enrolled in the study. Each performed a maximal treadmill exercise test according to the Bruce protocol after random treatment with sotalol, propranolol and placebo. Results: Sotalol significantly prolonged QTc(corrected QT) and JTc (corrected JT) intervals at rest compared with propranolol (QTc 324.86 ms vs 305.21 ms, P<0.001; JTc245.04 ms vs 224.17 ms, P<0.001) and placebo (QTc 324.86 ms vs 314.06 ms, P<0.01; JTc 245.04 ms vs. 232.69 ms, P<0.001).The JTc percent reduction increased progressively with each stage of exercise and correlated positively with exercise heart rate(r=0.148, P<0.01). The JTc percent reduction correlation with exercise heart rate did not exist with either propranolol or placebo.Conclusions: These results imply that with sotalol ventricular repolarization is progressively shortened after exercise. Thus the specific class Ⅲ antiarrhythmic activity of sotalol, present as delay of ventricular repolarization, may be attenuated during exercise.Such findings may imply the need to consider other antiarrythmic therapy during periods of stress-induced tachycardia.

  18. Cardiac alterations in human African trypanosomiasis (T.b. gambiense with respect to the disease stage and antiparasitic treatment.

    Directory of Open Access Journals (Sweden)

    Johannes A Blum

    Full Text Available BACKGROUND: In Human African Trypanosomiasis, neurological symptoms dominate and cardiac involvement has been suggested. Because of increasing resistance to the available drugs for HAT, new compounds are desperately needed. Evaluation of cardiotoxicity is one parameter of drug safety, but without knowledge of the baseline heart involvement in HAT, cardiologic findings and drug-induced alterations will be difficult to interpret. The aims of the study were to assess the frequency and characteristics of electrocardiographic findings in the first stage of HAT, to compare these findings to those of second stage patients and healthy controls and to assess any potential effects of different therapeutic antiparasitic compounds with respect to ECG changes after treatment. METHODS: Four hundred and six patients with first stage HAT were recruited in the Democratic Republic of Congo, Angola and Sudan between 2002 and 2007 in a series of clinical trials comparing the efficacy and safety of the experimental treatment DB289 to the standard first stage treatment, pentamidine. These ECGs were compared to the ECGs of healthy volunteers (n = 61 and to those of second stage HAT patients (n = 56. RESULTS: In first and second stage HAT, a prolonged QTc interval, repolarization changes and low voltage were significantly more frequent than in healthy controls. Treatment in first stage was associated with repolarization changes in both the DB289 and the pentamidine group to a similar extent. The QTc interval did not change during treatment. CONCLUSIONS: Cardiac involvement in HAT, as demonstrated by ECG alterations, appears early in the evolution of the disease. The prolongation of the QTC interval comprises a risk of fatal arrhythmias if new drugs with an additional potential of QTC prolongation will be used. During treatment ECG abnormalities such as repolarization changes consistent with peri-myocarditis occur frequently and appear to be associated with the disease

  19. Lesson Twenty-two The early repolarization variant

    Institute of Scientific and Technical Information of China (English)

    鲁端; 王劲

    2007-01-01

    @@ The ST-segment elevation seen in apparently healthy and asymptomatic persons,the so-called early repolarization variant (ERPV)1.Hiss et al reported that 91% of 6014 healthy men in the US Air Force who were between 16 and 58 years old had an ST-segment elevation of 0.1 to 0.3 mV in one or more precordial leads2.The elevation was most common and marked in lead V2.

  20. Study of the cardiac alterations in HIV-infected children consequent to the antiretroviral therapy: prospective study of 47 cases

    Directory of Open Access Journals (Sweden)

    Gesmar Volga Haddad Herdy

    2003-03-01

    Full Text Available OBJECTIVE: Detect of cardiac alterations in children with AIDS and compare their evolution with the administration of only one anti-retroviral and the recent cases who received drugs in combination. METHODS: We prospectively studied 47 children in 3 groups: group 1, 20 cases treated only with zidovudine; group 2, 10 patients treated initially with zidovudine and later with a combination of drugs and in group 3, 17 patients, who receiced two or three since the beginning. In all patients it was done chest X-ray, EKG and echocardiography every 6 months and after death complete pathological study. RESULTS: Among the 45 patients cases 26 (57% were index cases. Malnutrition, diarrhea tachycardia, signs of congestive heart failure, pericardial effusion, abnormal ventricular repolarization and arrhythmias were more frequent in group 1. Echocardiographic abnormalities were present in 10 (50% children of group 1. They were less frequent in the others two groups. In regard to the outcome in group 1, two patients had worsening of sings of cardiomyopaty and 4 died. Cardiac dysfunction in all cases of group 2 and 3 improved with the medication. CONCLUSION:- The children who received combination and their cardiac alterations had more favorable outcome than those who received only one drug.

  1. Change of Cardiac Reserve during Abnormal Pregnancy and Its Evaluation%异常妊娠妇女心脏储备的评估方法及变化规律

    Institute of Scientific and Technical Information of China (English)

    郭兴明; 钟丽莎; 王东; 有凤芝; 肖守中

    2011-01-01

    目的 研究异常妊娠妇女心脏储备的评估方法及变化规律.方法 采用运动心力监测仪对96例异常妊娠、356名正常妊娠及100名健康育龄妇女进行监测,在静息状态下记录心音图,测量第1心音幅值与第2心音幅值之比(S1/S2)、舒张期与收缩期的时限之比(D/S)和心率(HR).结果 正常妊娠组及异常妊娠组的S1/S2和HR明显高于健康育龄组,D/S明显低于健康育龄组(P均<0.001);异常妊娠组的S1/S2和HR明显高于正常妊娠组,D/S明显低于正常妊娠组(P均<0.001).D/S低于1.1及S1/S2高于1.8提示妊娠妇女危险性增加.4种常见异常妊娠的妇女心脏储备水平由低到高分别为子痫、双胎、妊娠性糖尿病和妊娠高血压.结论 妊娠期间调用了心脏储备,特别是异常妊娠妇女心脏负担更加沉重,心脏储备降到更低水平.用S1/S2、D/S和HR评估异常妊娠妇女心脏储备是可行的.%Objective To investigate the change of cardiac reserve during abnormal pregnancy and explore its evaluation methods.Methods Totally 96 women with abnormal pregnancies ( AP group), 356 women with normal pregnancies (NP group) , and 100 women of childbearing age ( CBA group) were monitored by the exercise cardiac contractility monitor (ECCM).Phonoeardiogram of participants at resting status was recorded by ECCM.The amplitude of first heart sound ( S1 ), the amplitude of second heart sound ( S2),cardiac cycle, diastolic duration (D), and systolic duration (S) were detected and then the S1/S2 ratio,the D/S ratio, and heart rate (HR) were calculated.Results Compared with the CBA group, S1/S2 ratio and HR were significantly higher and D/S was significantly lower in both AP group and NP group ( all P < 0.001 ).Compared with the NP group, S17S2 ratio and HR were significantly higher in AP group and D/S was significnatly lower ( all P < 0.001 ).A D/S ratio less than 1.1 or S1/S2 ratio higher than 1.8 was associated with higher risk of poor pregnancy

  2. Evaluation of repolarization dynamics using the QT-RR regression line slope and intercept relationship during 24-h Holter ECG.

    Science.gov (United States)

    Fujiki, Akira; Yoshioka, Ryozo; Sakabe, Masao

    2015-03-01

    QT-RR linear regression consists of two parameters, slope and intercept, and the aim of this study was to evaluate repolarization dynamics using the QT-RR linear regression slope and intercept relationship during 24-h Holter ECG. This study included 466 healthy subjects (54.6 ± 14.6 years; 200 men and 266 women) and 17 patients with ventricular arrhythmias, consisted of 10 patients with idiopathic ventricular fibrillation (IVF) and 7 patients with torsades de pointes (TDP). QT and RR intervals were measured from ECG waves based on a 15-s averaged ECG during 24-h Holter recording using an automatic QT analyzing system. The QT interval dependence on the RR interval was analyzed using a linear regression line for each subject ([QT] = A[RR] + B; where A is the slope and B is the y-intercept). The slope of the QT-RR regression line in healthy subjects was significantly greater in women than in men (0.185 ± 0.036 vs. 0.161 ± 0.033, p Holter ECG may become a simple useful marker for abnormality of ventricular repolarization dynamics.

  3. Arrhythmogenic remodelling of activation and repolarization in the failing human heart.

    Science.gov (United States)

    Holzem, Katherine M; Efimov, Igor R

    2012-11-01

    Heart failure is a major cause of disability and death worldwide, and approximately half of heart failure-related deaths are sudden and presumably due to ventricular arrhythmias. Patients with heart failure have been shown to be at 6- to 9-fold increased risk of sudden cardiac death compared to the general population. (AHA. Heart Disease and Stroke Statistics-2003 Update. Heart and Stroke Facts. Dallas, TX: American Heart Association; 2002) Thus, electrophysiological remodelling associated with heart failure is a leading cause of disease mortality and has been a major investigational focus examined using many animal models of heart failure. While these studies have provided an important foundation for understanding the arrhythmogenic pathophysiology of heart failure, the need for corroborating studies conducted on human heart tissue has been increasingly recognized. Many human heart studies of conduction and repolarization remodelling have now been published and shed some light on important, potentially arrhythmogenic, changes in human heart failure. These studies are being conducted at multiple experimental scales from isolated cells to whole-tissue preparations and have provided insight into regulatory mechanisms such as decreased protein expression, alternative mRNA splicing of ion channel genes, and defective cellular trafficking. Further investigations of heart failure in the human myocardium will be essential for determining possible therapeutic targets to prevent arrhythmia in heart failure and for facilitating the translation of basic research findings to the clinical realm.

  4. Zebrafish: a novel research tool for cardiac (patho)electrophysiology and ion channel disorders.

    Science.gov (United States)

    Verkerk, Arie O; Remme, Carol Ann

    2012-01-01

    The zebrafish is a cold-blooded tropical freshwater teleost with two-chamber heart morphology. A major advantage of the zebrafish for heart studies is that the embryo is transparent, allowing for easy assessment of heart development, heart rate analysis and phenotypic characterization. Moreover, rapid and effective gene-specific knockdown can be achieved using morpholino oligonucleotides. Lastly, zebrafish are small in size, are easy to maintain and house, grow fast, and have large offspring size, making them a cost-efficient research model. Zebrafish embryonic and adult heart rates as well as action potential (AP) shape and duration and electrocardiogram morphology closely resemble those of humans. However, whether the zebrafish is truly an attractive alternative model for human cardiac electrophysiology depends on the presence and gating properties of the various ion channels in the zebrafish heart, but studies into the latter are as yet limited. The rapid component of the delayed rectifier K(+) current (I(Kr)) remains the best characterized and validated ion current in zebrafish myocytes, and zebrafish may represent a valuable model to investigate human I(Kr) channel-related disease, including long QT syndrome. Arguments against the use of zebrafish as model for human cardiac (patho)electrophysiology include its cold-bloodedness and two-chamber heart morphology, absence of t-tubuli, sarcoplamatic reticulum function, and a different profile of various depolarizing and repolarizing ion channels, including a limited Na(+) current density. Based on the currently available literature, we propose that zebrafish may constitute a relevant research model for investigating ion channel disorders associated with abnormal repolarization, but may be less suitable for studying depolarization disorders or Ca(2+)-modulated arrhythmias.

  5. Zebrafish: a novel research tool for cardiac (pathoelectrophysiology and ion channel disorders

    Directory of Open Access Journals (Sweden)

    Arie O Verkerk

    2012-07-01

    Full Text Available The zebrafish is a cold-blooded tropical freshwater teleost with a two-chamber heart morphology, typical for non-mammalian vertebrates. A major advantage of the zebrafish for heart studies is that the embryo is transparent, allowing for easy assessment of heart development, heart rate analysis and phenotypic characterization. Moreover, rapid and effective gene-specific knockdown can be achieved using morpholino oligonucleotides. Lastly, zebrafish are small in size, are easy to maintain and house, grow fast, and have large offspring size, making them a cost-efficient research model. Zebrafish embryonic and adult heart rates as well as action potential shape and duration and electrocardiogram morphology closely resemble those of humans. However, whether the zebrafish is truly an attractive alternative model for human cardiac electrophysiology depends on the presence and gating properties of the various ion channels in the zebrafish heart, but studies into the latter are as yet limited. The rapid component of the delayed rectifier K+ current (IKr remains the best characterized and validated ion current in zebrafish myocytes, and zebrafish may represent a valuable model to investigate human IKr channel related disease, including long QT syndrome. Arguments against the use of zebrafish as model for human cardiac (pathoelectrophysiology include its cold-bloodedness and two-chamber heart morphology, absence of t-tubuli, sarcoplamatic reticulum function, and a different profile of various depolarizing and repolarizing ion channels, including a limited Na+ current density. Based on the currently available literature, we propose that zebrafish may constitute a relevant research model for investigating ion channel disorders associated with abnormal repolarization, but may be less suitable for studying depolarization disorders or Ca2+-modulated arrhythmias.

  6. Leptin decreases heart rate associated with increased ventricular repolarization via its receptor.

    Science.gov (United States)

    Lin, Yen-Chang; Huang, Jianying; Hileman, Stan; Martin, Karen H; Hull, Robert; Davis, Mary; Yu, Han-Gang

    2015-11-15

    Leptin has been proposed to modulate cardiac electrical properties via β-adrenergic receptor activation. The presence of leptin receptors and adipocytes in myocardium raised a question as to whether leptin can directly modulate cardiac electrical properties such as heart rate and QT interval via its receptor. In this work, the role of local direct actions of leptin on heart rate and ventricular repolarization was investigated. We identified the protein expression of leptin receptors at cell surface of sinus node, atrial, and ventricular myocytes isolated from rat heart. Leptin at low doses (0.1-30 μg/kg) decreased resting heart rate; at high doses (150-300 μg/kg), leptin induced a biphasic effect (decrease and then increase) on heart rate. In the presence of high-dose propranolol (30 mg/kg), high-dose leptin only reduced heart rate and sometimes caused sinus pauses and ventricular tachycardia. The leptin-induced inhibition of resting heart rate was fully reversed by leptin antagonist. Leptin also increased heart rate-corrected QT interval (QTc), and leptin antagonist did not. In isolated ventricular myocytes, leptin (0.03-0.3 μg/ml) reversibly increased the action potential duration. These results supported our hypothesis that in addition to indirect pathway via sympathetic tone, leptin can directly decrease heart rate and increase QT interval via its receptor independent of β-adrenergic receptor stimulation. During inhibition of β-adrenergic receptor activity, high concentration of leptin in myocardium can cause deep bradycardia, prolonged QT interval, and ventricular arrhythmias.

  7. The T-peak–T-end Interval as a Marker of Repolarization Abnormality

    DEFF Research Database (Denmark)

    Bhuiyan, Tanveer A.; Graff, Claus; Kanters, Jørgen K.;

    2015-01-01

    a significant increase of both TpTe and QT from baseline is apparent with QT-prolonging drugs, the TpTe/QT ratio remained the same at baseline and after drug administration, thus indicating that prolongation of TpTe is just a fractional part of total QT prolongation. In the presence of notched or flattened T......-waves, the uncertainty associated with measurement of the TpTe interval increases. The errors in TpTe for individual subjects may be substantial, thus complicating the use of TpTe for follow-up of individuals. CONCLUSIONS: The duration of the QT interval and TpTe are closely related. Drugs appear to prolong the Tp...

  8. Níveis de hemoglobina glicosilada e anomalias cardíacas em fetos de mães com diabetes mellitus Glycosylated hemoglobin levels and cardiac abnormalities in fetuses of diabetic mothers

    Directory of Open Access Journals (Sweden)

    Ivo Behle

    1998-06-01

    Full Text Available Avaliou-se, prospectivamente, a existência de relação entre o controle glicêmico materno, na primeira metade da gestação, com a ocorrência de anomalias cardíacas fetais, em gestantes com diabetes mellitus. O nível da hemoglobina glicosilada (HbA1c foi determinado em 127 grávidas, por ocasião da primeira visita pré-natal. Nove eram portadoras de diabetes do tipo I, 77 do tipo II e 41 de Diabetes mellitus gestacional (DMG. Todas foram submetidas a ecocardiografia fetal detalhada na 28ª (±4,1 semana da gestação. Em 31 dos 127 fetos (24,4% foram detectadas anomalias cardíacas. Em 10 (7,87%, foram diagnosticadas anomalias cardíacas estruturais e, em 21 (16,53%, miocardiopatia hipertrófica como anomalia cardíaca isolada. A média das dosagens de HbA1c no grupo de gestantes sem anomalias cardíacas (5,6% foi estatisticamente diferente da média das HbA1c do grupo com anomalias (10,1% (pWe analyze prospectively the existence of a relationship between the mother's glycemic control, in the first half of pregnancy, and the occurrence of abnormal fetal cardiac abnormalities, in pregnant women with diabetes mellitus. In 127 pregnant women, the level of glycosylated hemoglobin was determined on the first visit during prenatal care. Nine patients had type I diabetes, 77 type II and 41 gestational diabetes mellitus (GDM. All mothers were submitted to detailed fetal echocardiography, during the 28th ± 4.127 week of gestation. In 31 (24.4% of the 127 fetuses cardiac anomalies were detected. In 10 (7.87% an isolated cardiac anomaly was identified. Mean HbA1c in the group of pregnant women without cardiac anomalies (5.64% was statistically different from the group with anomalies (10.14% (p<0.0001. The receiver-operator characteristic, representing the balance between sensitivity (92.83% and specificity (98.92% in the diagnosis of structural cardiac abnormalities, showed a cut-off point at the 7.5% HbA1c level. In nine of ten fetuses with

  9. Level of urinary liver-type fatty acid-binding protein is associated with cardiac markers and electrocardiographic abnormalities in type-2 diabetes with chronic kidney disease stage G1 and G2.

    Science.gov (United States)

    Maeda, Yoshiteru; Suzuki, Atsushi; Ishii, Junnichi; Sekiguchi-Ueda, Sahoko; Shibata, Megumi; Yoshino, Yasumasa; Asano, Shogo; Hayakawa, Nobuki; Nakamura, Kazuhiro; Akiyama, Yasukazu; Kitagawa, Fumihiko; Sakuishi, Toshiaki; Fujita, Takashi; Hashimoto, Shuji; Ozaki, Yukio; Itoh, Mitsuyasu

    2015-05-01

    Urinary liver-type fatty acid-binding protein (L-FABP) reflects the degree of stress in proximal tubules of the kidney. We examined the level of L-FABP in type-2 diabetes mellitus (T2DM) patients with chronic kidney disease (CKD) stage G1 and G2, and its relationship with cardiac markers and electrocardiographic (ECG) abnormalities. T2DM patients whose estimated glomerular filtration rate (eGFR) was ≥60 mL/min/1.73 m(2) were recruited [n = 276 (165 males), mean age 64 years]. The median level of urinary L-FABP was 6.6 μg/gCr. Urinary L-FABP showed significant correlation with urinary albumin-to-creatinine ratio (ACR) (r = 0.51, p L-FABP ≤8.4 μg/gCr and ACR ≤30 mg/gCr; group 2, L-FABP ≤8.4 μg/gCr and ACR >30 mg/gCr; group 3, L-FABP >8.4 μg/gCr and ACR ≤30 mg/gCr; group 4, L-FABP >8.4 μg/gCr and ACR >30 mg/gCr). Compared with group 1, group 4 was significantly higher in systolic blood pressure, and eGFR using standardized serum cystatin C, high-sensitivity troponin T, and N-terminal pro-brain natriuretic peptide (NT-proBNP). Group 4 had significantly higher level of NT-proBNP than group 3. Groups 2, 3 and 4 showed more ECG abnormalities than group 1. These findings suggest that simultaneous measurement of urinary L-FABP and ACR should be useful to assess cardiovascular damage reflecting on the elevation of cardiac markers and ECG abnormalities in T2DM with CKD G1 and G2.

  10. [Effect of the heart electric stimulation on repolarization of fish and amphibian ventricular myocardium].

    Science.gov (United States)

    Azarov, Ia É; Kibler, N A; Vaĭshnoraĭte, M A; Tsvetkova, A S; Kharin, S N; Vitiazev, V A; Shmakov, D N

    2013-01-01

    By the method of synchronous multielectrode cartography (24-unipolar leads), distribution of durations and time of end of repolarization were studied on ventricular epicardium of pikes (Esox lucius) and frogs (Rana esculenta) and in ventricular intramural layers of toads (Bufo bufo) at the ectopic heart excitation. The time of arrival of the excitation wave and of the end of repolarization in each lead was determined from the minimum of time derivative of potential at the period of the QRS complex and by minimum of the T wave, respectively. It has been established that at the ventricle electrostimulation, alongside with deceleration and a change of sequence of the myocardium activation, there occurs redistribution of local repolarization durations: in areas of late activation the repolarization being longer than in zones of early activation (p < 0.05). At stimulation, the apicobasal gradient of repolarization is predominantly changed due to electrophysiological processes in the apical areas. In all studied species. at ectopical excitation of the heart ventricle the sequence of its repolarization repeats the depolarization sequence due to delay of activation (in fish) and redistribution of repolarization durations (in amphibians).

  11. Sex Difference in the Repolarization Currents of Rabbit Ventricular Cells

    Institute of Scientific and Technical Information of China (English)

    RUAN Yanfei; LIU Nian; ZHOU Qiang; LI Yang; WANG Lin

    2005-01-01

    Summary: The current difference between male and female rabbit ventricular myocytes was investigated for elucidating the mechanism of longer QT interval and higher incidence of drug-associated torsade de pointes in female rabbits than in male rabbits. Whole cell patch clamp technique was used to record APD, Ito, IK,tail, IK1 and ICa,L of myocytes from left ventricular apex. There was no difference in the membrane capacitance between male and female rabbit myocytes. APD90 was longer in female rabbits (560.4±26.5 ms, n=15) than in male ones (489.0±20.7 ms, n=14), P0.05). The lower IK,tail of female rabbit myocytes may contribute to the longer repolarization and the higher incidence of drug-associated torsade de pointes.

  12. Early repolarization as a predictor of premature ventricular beats.

    Science.gov (United States)

    Matoshvili, Z T; Petriashvili, Sh G; Archadze, A T; Azaladze, I G

    2015-02-01

    Early repolarization pattern (ERP) is a common ECG variant, characterized by J point elevation manifested either as terminal QRS slurring (the transition from the QRS segment to the ST segment) or notching (a positive deflection inscribed on terminal QRS complex) associated with concave upward ST-segment elevation and prominent T waves in at least two contiguous leads. Aim of this observational study was to compare number of premature ventricular beats in the different groups of patients with early repolarization. The result of this observational study shows that there are: 1,74 fold higher number of premature ventricular beats in 41-74 year subgroup VS 19-40 year subgroup; 1,31 fold higher number of premature ventricular beats in male subgroup VS female subgroup (But this difference is not statistically significant, because t=1,49, p=0,141); 2,85 fold higher number of premature ventricular beats in CAD+ERP subgroup VS ERP without CAD subgroup; 1,74 fold higher number of premature ventricular beats in HF+ERP subgroup VS ERP without HF subgroup; 1,81 fold higher number of premature ventricular beats in CAD+ERP subgroup VS CAD without ERP subgroup; 1,58 fold higher number of premature ventricular beats in HF+ERP subgroup VS HF without ERP subgroup; So, CAD+ERP is very arrhythmogenic condition, after this is HF+ERP, Then Age. This study shows that ERP independently increase number of PVB in different groups (CAD, HF). This is principally new and very important result. Also the number of patients is enough to make this conclusion.

  13. Early cardiac failure in a child with Becker muscular dystrophy is due to an abnormally low amount of dystrophin transcript lacking exon 13.

    Science.gov (United States)

    Ishigaki, C; Patria, S Y; Nishio, H; Yoshioka, A; Matsuo, M

    1997-12-01

    Two Japanese brothers with Becker muscular dystrophy were shown by polymerase chain reaction (PCR) and cDNA sequence analysis to produce a dystrophin gene transcript lacking a single exon: that is, number 13. Despite having the same deletion mutation, the brothers showed clearly different clinical phenotypes: the younger brother developed cardiac failure at the age of nine, while the elder brother was asymptomatic. As alternative splicing was not responsible for this clinical difference, the amount of dystrophin transcript was examined by using reverse transcription semi-nested and parallel PCR. The results showed that the amount of the dystrophin transcript in the younger brother was 20% of that of the elder brother. This finding suggested that lesser amount of dystrophin transcript in the younger brother was responsible for the early onset of cardiac failure. This would represent a novel molecular mechanism for dystrophinopathy.

  14. FINE PARTICLE EXPOSURE IS ASSOCIATED WITH ALTERED VENTRICULAR REPOLARIZATION

    Science.gov (United States)

    Exposure to fine airborne particulate matter (PM2.5) has previously been associated with cardiac events, especially in older people with cardiovascular disease and in diabetics. This study examined the cardiac effects of short-term exposures to ambient PM2.5 in a prospective pane...

  15. Serum Levels of Tissue Inhibitors of Metalloproteinase 2 in Patients With Systemic Sclerosis With Duration More Than 2 Years: Correlation With Cardiac and Pulmonary Abnormalities

    Directory of Open Access Journals (Sweden)

    Amira Shahin

    2006-01-01

    with elevated TIMP-2 levels was significantly higher than dSSc patients with normal levels (P=.013. Four patients out of five with elevated TIMP-2 levels showed diastolic dysfunction (80%, compared to 2 out of 15 lSSc patients with normal levels (13.3%, with P=.014. Our research, though involving a small group of patients, points to the probable role of TIMP-2 in the development of pulmonary lesions in dSSc patients and cardiac lesions in lSSc patients with duration equal to or more than 2 years.

  16. Role of the late sodium current in rate-dependent repolarization of the canine ventricle.

    Science.gov (United States)

    Zhang, Hong; Yang, Lin; Yang, Zhao; Zheng, Xiao

    2013-12-31

    Late sodium current I(NaL) is an inward current participating in maintaining the plateau of the action potential. So far its role in the repolarization of canine hearts is not well known. In this paper, by taking advantage of a computer simulation method, we developed a one-dimensional transmural tissue to study the impacts of I(NaL) on rate-dependent repolarization and its ionic basis in the canine ventricle. An OpenMP parallel algorithm was performed on a four-core personal computer to accelerate the simulation. The results demonstrated that action potential durations of midmyocytes showed greater rate dependence than the endo- and epi-myocytes. When the pacing rate was reduced, repolarization of the tissue was prolonged while the transmural dispersion of repolarization (TDR) was enlarged. The enhancement of I(NaL) further amplified this rate-dependent repolarization and TDR meanwhile increased the risk of arrhythmogenesis. I(NaL) was found highly sensitive to the pacing rate by calculating its kinetics. The study suggested that I(NaL) played an important role in the rate-dependent repolarization of the canine ventricle. Selective blockade of I(NaL) could have clinical benefits, especially for such pathological conditions with enhanced I(NaL) as long QT 3 syndrome and heart failure.

  17. Drug-induced Inhibition and Trafficking Disruption of ion Channels: Pathogenesis of QT Abnormalities and Drug-induced Fatal Arrhythmias.

    Science.gov (United States)

    Cubeddu, Luigi X

    2016-01-01

    Risk of severe and fatal ventricular arrhythmias, presenting as Torsade de Pointes (TdP), is increased in congenital and acquired forms of long QT syndromes (LQTS). Drug-induced inhibition of K+ currents, IKs, IKr, IK1, and/or Ito, delay repolarization, prolong QT, and increase the risk of TdP. Drug-induced interference with IKr is the most common cause of acquired LQTS/TdP. Multiple drugs bind to KNCH2-hERG-K+ channels affecting IKr, including antiarrythmics, antibiotics, antivirals, azole-antifungals, antimalarials, anticancer, antiemetics, prokinetics, antipsychotics, and antidepressants. Azithromycin has been recently added to this list. In addition to direct channel inhibition, some drugs interfere with the traffic of channels from the endoplasmic reticulum to the cell membrane, decreasing mature channel membrane density; e.g., pentamidine, geldalamicin, arsenic trioxide, digoxin, and probucol. Other drugs, such as ketoconazole, fluoxetine, norfluoxetine, citalopram, escitalopram, donepezil, tamoxifen, endoxifen, atazanavir, and roxitromycin, induce both direct channel inhibition and impaired channel trafficking. Although many drugs prolong the QT interval, TdP is a rare event. The following conditions increase the risk of drug-induced TdP: a) Disease states/electrolyte levels (heart failure, structural cardiac disease, bradycardia, hypokalemia); b) Pharmacogenomic variables (presence of congenital LQTS, subclinical ion-channel mutations, history of or having a relative with history of drug-induced long QT/TdP); c) Pharmacodynamic and kinetic factors (high doses, women, elderly, metabolism inhibitors, combining two or more QT prolonging drugs, drugs that prolong the QT and increase QT dispersion, and drugs with multiple actions on ion channels). Because most of these conditions are preventable, careful evaluation of risk factors and increased knowledge of drug use associated with repolarization abnormalities are strongly recommended.

  18. 心导管介入治疗先天性心脏病复合畸形的护理%Nursing care of patients with congenital compound heart abnormality treated by interventional therapy of cardiac catheterization

    Institute of Scientific and Technical Information of China (English)

    杨学凤

    2016-01-01

    Objective:To analyze the nursing care of patients with congenital compound heart abnormality treated by interventional therapy of cardiac catheterization.Methods:25 patients with congenital compound heart abnormality treated by interventional therapy of cardiac catheterization were selected.We summarized nursing experience.Results:Closure operation was successful in 24 patients, and 2 patients received cardiac surgery after surgery;1 case of failure due to serious defect. There were 2 cases of hematoma in the puncture site after operation,and the hematoma disappeared after treatment.Mechanical hemolysis,deep venous thrombosis,brachial plexus injury and other serious complications were not occurred in patients. Conclusion:To strengthen the perioperative nursing of patients with congenital heart disease combined malformation in perioperative care can effectively improve the success rate of surgical closure,and avoid the incidence of serious complications.%目的:分析心导管介入治疗先天性心脏病复合畸形的护理。方法:收治心导管介入治疗先天性心脏病复合畸形患者25例,总结护理体会。结果:24例患者封堵手术成功,术后转入心脏外科接受治疗2例;因缺损严重封堵失败1例;术后出现穿刺部位血肿,处理后血肿消失2例;患者未出现机械性溶血、深静脉血栓、臂丛神经损伤等严重并发症。结论:加强先天性心脏病复合畸形患者介入手术的围手术期护理可有效提高手术封堵成功率,避免和减少术后严重并发症发生。

  19. Cyclical Modulation of Human Ventricular Repolarization by Respiration

    Directory of Open Access Journals (Sweden)

    Ben eHanson

    2012-09-01

    Full Text Available Background: Respiratory modulation of autonomic input to the sinus node results in cyclical modulation of heart rate, known as respiratory sinus arrhythmia. We hypothesized that the respiratory cycle may also exert cyclical modulation on ventricular repolarization, which may be separately measurable using local endocardial recordings.Methods and Results: The study included 16 subjects with normal ventricles undergoing routine clinical electrophysiological procedures for supraventricular arrhythmias. Unipolar electrograms were recorded from 10 right and 10 left ventricular endocardial sites. Breathing was voluntarily regulated at 5 fixed frequencies (6, 9, 12, 15 and 30 breaths per minute and heart rate was clamped by RV pacing. Activation-recovery intervals (ARI: a surrogate for APD exhibited significant (p<0.025 cyclical variation at the respiratory frequency in all subjects; ARI shortened with inspiration and lengthened with expiration. Peak-to-peak ARI variation ranged from 0-26 ms; the spatial pattern varied with subject. Arterial blood pressure also oscillated at the respiratory frequency (p<0.025 and lagged behind respiration by between 1.5 s and 0.65s from slowest to fastest breathing rates respectively. Systolic oscillation amplitude was significantly greater than diastolic (14±5 vs. 8±4 mmHg ± SD, p<0.001. Conclusions: Observations in humans with healthy ventricles using multiple left and right ventricular endocardial recordings showed that ARI (APD varied cyclically with respiration.

  20. Effects of neutral sulfate berberine on LPS-induced cardiomyocyte TNF-αsecretion, abnormal calcium cycling, and cardiac dysfunction in rats

    Institute of Scientific and Technical Information of China (English)

    Jing YANG; Hua-dong WANG; Da-xiang LU; Yan-ping WANG; Ren-bin QI; Jing LI; Fei LI; Chu-jie LI

    2006-01-01

    Aim: To evaluate the effect of neutral sulfate berberine on cardiac function, tumornecrosis factor α (TNF-α) release, and intracellular calcium concentration ([Ca2+]i)in cardiomyocytes exposed to lipopolysaccharide (LPS). Methods: Primary cultured rat cardiomyocytes were prepared from ventricles of 3-4-day old SpragueDawley rats. TNF-α concentrations in cell-conditioned media were measured by using a Quantikine enzyme-linked immunosorbent assay kit, and cardiomyocyte [Ca2+]i was measured by using Fura-2/AM. The isolated rat hearts were perfused in the Langendorff mode. Results: LPS at doses of 1, 5, 10, and 20 μg/mL markedly stimulated TNF-α secretion from cardiomyocytes, and neutral sulfate berberine inhibited LPS-induced TNF-α production. Intracellular calcium concentration was significantly decreased after LPS stimulation for 1 h, and increased 2 h after LPS treatment. Pretreatment with neutral sulfate berberine reversed the LPS-induced [Ca2+]i alterations, although neutral sulfate berberine did not inhibit a rapid increase in cardiomyocyte [Ca2+]i induced by LPS. Perfusion of isolated hearts with LPS (100 μg/mL) for 20 min resulted in significantly impaired cardiac performance at 120 min after LPS challenge: the maximal rate of left ventricular pressure rise and fall (±dp/dtmax) decreased compared with the control. In contrast, ±dp/dtmax at 120min in hearts perfused with neutral sulfate berberine (1 μmol/L) for 10 min followed by 20 min LPS (100 μg/mL) was greater than the corresponding value in the LPS group. Conclusion: Neutral sulfate berberine inhibits LPS-stimulated myocardial TNF-α production, impairs calcium cycling, and improves LPS-induced contractile dysfunction in intact heart.

  1. Rastreamento Pré-natal de Anormalidades Cardíacas: Papel da Ultra–sonografia Obstétrica de Rotina renatal Screening of Cardiac Abnormalities: The Role of Routine Obstetrical Ultrasound

    Directory of Open Access Journals (Sweden)

    Tzvi Bacaltchuk

    2001-10-01

    estudo ecográfico, ao passo que apenas 3,4% dos pacientes sem suspeita pré-natal apresentaram alterações do ritmo (p=0,009. Constituíram fatores comparativos significantes entre o grupo com suspeita pré-natal e o sem suspeita a paridade (p=0,029, o parto cesáreo (p=0,006, a internação em unidade de tratamento intensivo (p=0,046 e a escolaridade paterna (p=0,014. À análise multivariada, apenas a presença de alteração do ritmo cardíaco durante a ultra-sonografia obstétrica mostrou-se como variável independente associada à suspeita pré-natal de anormalidade cardíaca. Conclusões: a ultra-sonografia obstétrica de rotina ainda tem sido subutilizada no rastreamento pré-natal de cardiopatias congênitas. O treinamento dirigido dos ultra-sonografistas e a conscientização do meio obstétrico e da própria população podem ser os instrumentos para aumentar a eficácia deste método.Purpose: to evaluate the role of routine obstetrical ultrasound scan in suspecting the presence of fetal congenital heart diseases and severe arrhythmias, as well as the factors involved in its accuracy. Methods: the sample was made up of 77 neonates and infants hospitalized at the Institute of Cardiology of Rio Grande do Sul from May to October of 2000, with confirmed postnatal diagnosis of structural heart disease or severe arrhythmia, whose mothers had been submitted to at least one obstetrical ultrasound scan after 18 weeks of gestation. After informed consent, a customized standard questionnaire was used. Categorical variables were compared using chi² test or Fisher's exact test and a logistic regression model was used to determine independent variables possibly involved in the prenatal suspicion of cardiac abnormalities. Results: in 19 patients (24.6%, obstetrical ultrasound was able to rise prenatal suspicion of structural or rhythm abnormalities. Considering only congenital heart diseases, this prevalence was 19.2% (14/73. In 73.7% of these cases, the cardiac disorder

  2. Experimentally-Based Computational Investigation into Beat-To-Beat Variability in Ventricular Repolarization and Its Response to Ionic Current Inhibition.

    Directory of Open Access Journals (Sweden)

    E Pueyo

    Full Text Available Beat-to-beat variability in repolarization (BVR has been proposed as an arrhythmic risk marker for disease and pharmacological action. The mechanisms are unclear but BVR is thought to be a cell level manifestation of ion channel stochasticity, modulated by cell-to-cell differences in ionic conductances. In this study, we describe the construction of an experimentally-calibrated set of stochastic cardiac cell models that captures both BVR and cell-to-cell differences in BVR displayed in isolated canine action potential measurements using pharmacological agents. Simulated and experimental ranges of BVR are compared in control and under pharmacological inhibition, and the key ionic currents determining BVR under physiological and pharmacological conditions are identified. Results show that the 4-aminopyridine-sensitive transient outward potassium current, Ito1, is a fundamental driver of BVR in control and upon complete inhibition of the slow delayed rectifier potassium current, IKs. In contrast, IKs and the L-type calcium current, ICaL, become the major contributors to BVR upon inhibition of the fast delayed rectifier potassium current, IKr. This highlights both IKs and Ito1 as key contributors to repolarization reserve. Partial correlation analysis identifies the distribution of Ito1 channel numbers as an important independent determinant of the magnitude of BVR and drug-induced change in BVR in control and under pharmacological inhibition of ionic currents. Distributions in the number of IKs and ICaL channels only become independent determinants of the magnitude of BVR upon complete inhibition of IKr. These findings provide quantitative insights into the ionic causes of BVR as a marker for repolarization reserve, both under control condition and pharmacological inhibition.

  3. The role of late I Na in development of cardiac arrhythmias.

    Science.gov (United States)

    Antzelevitch, Charles; Nesterenko, Vladislav; Shryock, John C; Rajamani, Sridharan; Song, Yejia; Belardinelli, Luiz

    2014-01-01

    Late I Na is an integral part of the sodium current, which persists long after the fast-inactivating component. The magnitude of the late I Na is relatively small in all species and in all types of cardiomyocytes as compared with the amplitude of the fast sodium current, but it contributes significantly to the shape and duration of the action potential. This late component had been shown to increase in several acquired or congenital conditions, including hypoxia, oxidative stress, and heart failure, or due to mutations in SCN5A, which encodes the α-subunit of the sodium channel, as well as in channel-interacting proteins, including multiple β subunits and anchoring proteins. Patients with enhanced late I Na exhibit the type-3 long QT syndrome (LQT3) characterized by high propensity for the life-threatening ventricular arrhythmias, such as Torsade de Pointes (TdP), as well as for atrial fibrillation. There are several distinct mechanisms of arrhythmogenesis due to abnormal late I Na, including abnormal automaticity, early and delayed after depolarization-induced triggered activity, and dramatic increase of ventricular dispersion of repolarization. Many local anesthetic and antiarrhythmic agents have a higher potency to block late I Na as compared with fast I Na. Several novel compounds, including ranolazine, GS-458967, and F15845, appear to be the most selective inhibitors of cardiac late I Na reported to date. Selective inhibition of late I Na is expected to be an effective strategy for correcting these acquired and congenital channelopathies.

  4. Derivation of Human Induced Pluripotent Stem (iPS) Cells to Heritable Cardiac Arrhythmias

    Science.gov (United States)

    2016-03-14

    Inherited Cardiac Arrythmias; Long QT Syndrome (LQTS); Brugada Syndrome (BrS); Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT); Early Repolarization Syndrome (ERS); Arrhythmogenic Cardiomyopathy (AC, ARVD/C); Hypertrophic Cardiomyopathy (HCM); Dilated Cardiomyopathy (DCM); Muscular Dystrophies (Duchenne, Becker, Myotonic Dystrophy); Normal Control Subjects

  5. Relationship between Ambient Fine Particles and Ventricular Repolarization Changes and Heart Rate Variability of Elderly People with Heart Disease in Beijing, China

    Institute of Scientific and Technical Information of China (English)

    XU Mei Mei; JIA Yu Ping; LI Guo Xing; LIU Li Qun; MO Yun Zheng; JIN Xiao Bin; PAN Xiao Chuan

    2013-01-01

    Objective To explore the effects of particulate matters less than 2.5 μm in aerodynamic diameter (PM2.5) on heart repolarization/depolarization and heart rate variability (HRV). Methods We conducted a panel study for elderly subjects with heart disease in Beijing from 2007 to 2008. PM2.5 was measured at a fixed station for 20 h continuously each day while electrocardiogram (ECG) indexes of 42 subjects were also recorded repeatedly. Meteorological data was obtained from the China Meteorological Data Sharing Service System. A mixed linear regression model was used to estimate the associations between PM2.5 and the ECG indexes. The model was adjusted for age, body mass index, sex, day of the week and meteorology. Results Significant adverse effects of PM2.5 on ECG indexes reflecting HRV were observed statistically and the strongest effect of PM2.5 on HRV was on lag 1 day in our study. However, there were no associations between PM2.5 and ECG indexes reflecting heart repolarization/depolarization. Additionally, the effects of PM2.5 on subjects with hypertension were larger than on the subjects without hypertension. Conclusion This study showed ambient PM2.5 could affect cardiac autonomic function of the elderly people with heart disease, and subjects with hypertension appeared to be more susceptive to the autonomic dysfunction induced by PM2.5.

  6. An estimate of the dispersion of repolarization times based on a biophysical model of the ECG.

    Science.gov (United States)

    Sassi, Roberto; Mainardi, Luca T

    2011-12-01

    Temporal heterogeneity of ventricular repolarization is a key quantity for the development of ventricular reentrant arrhythmia. In this paper, we introduce the V-index, a novel ECG-based estimator of the standard deviation of ventricular myocytes' repolarization times s(ϑ). Differently from other ECG metrics of repolarization heterogeneity, the V-index was derived from the analysis of a biophysical model of the ECG, where repolarization is described by the dominant T-wave (DTW) paradigm. The model explains the shape of T-waves in each lead as a projection of a main waveform (the DTW) and its derivatives weighted by scalars, the lead factors. A mathematical formula is derived to link the heterogeneity of ventricular repolarization s(ϑ) and the V-index. The formula was verified using synthetic 12-lead ECGs generated with a direct electrophysiological model for increasing values of s(ϑ) (in the range 20-70 ms). A linear relationship between the V-index and s(ϑ) was observed, V ≈ 0.675 s(ϑ) + 1.8 ms (R(2) = 0.9992). Finally, 68 ECGs from the E-OTH-12-0068-010 database of the Telemetric and Holter ECG Warehouse were analyzed. The V-index coherently increased after sotalol administration, a drug known to have QT-prolonging potential (p < 0.001).

  7. Introduction: December 2015 HeartWeek Issue of Cardiology in the Young - Highlights of HeartWeek 2015: Challenges and Dilemmas of Pediatric Cardiac Care including Heart Failure in Children and Congenital Abnormalities of the Coronary Arteries.

    Science.gov (United States)

    Jacobs, Jeffrey P

    2015-12-01

    This December Issue of Cardiology in the Young represents the 13th annual publication in Cardiology in the Young generated from the two meetings that composed "HeartWeek in Florida". "HeartWeek in Florida", the joint collaborative project sponsored by the Cardiac Centre at the Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, together with Johns Hopkins All Children's Heart Institute of Saint Petersburg, Florida, averages over 1000 attendees every year and is now recognised as one of the major planks of continuing medical and nursing education for those working in the fields of diagnosis and treatment of cardiac disease in the foetus, neonate, infant, child, and adult. "HeartWeek in Florida" combines the International Symposium on Congenital Heart Disease, organised by All Children's Hospital and Johns Hopkins Medicine, and entering its 16th year, with the Annual Postgraduate Course in Paediatric Cardiovascular Disease, organised by The Children's Hospital of Philadelphia entering its 19th year. This December 2015 Issue of Cardiology in the Young features highlights of the two meetings that compose HeartWeek. Johns Hopkins All Children's Heart Institute's 15th Annual International Symposium on Congenital Heart Disease was held at the Renaissance Vinoy Resort & Golf Club, Saint Petersburg, Florida, from Friday, 6 February, 2015, to Monday, 9 February, 2015. This Symposium was co-sponsored by The American Association for Thoracic Surgery and its special focus was "Congenital Abnormalities of the Coronary Arteries". The Children's Hospital of Philadelphia's annual meeting - Cardiology 2015, the 18th Annual Update on Paediatric and Congenital Cardiovascular Disease: "Challenges and Dilemmas" - was held at the Hyatt Regency Scottsdale Resort and Spa at Gainey Ranch, Scottsdale, Arizona, from Wednesday, 11 February, 2015, to Sunday, 15 February, 2015. We would like to acknowledge the tremendous contributions made to paediatric and congenital cardiac care

  8. Effect of Autonomic Nervous System on the Transmurai Dispersion of Ventricular Repolarization in Intact Canine

    Institute of Scientific and Technical Information of China (English)

    张存泰; 徐大文; 李泱; 刘念; 王琳; 陆再英

    2004-01-01

    Summary: The effect of the autonomic nerves on the transmural dispersion of ventricular repolarization in intact canine was investigated. By using the monophasic action potential (MAP) recording technique, monophasic action potentials (MAPs) of the epicardium (Epi), midmyocardium (Mid)and endocardium (Endo) were recorded simultaneously by specially designed plunge-needle electrodes at the left ventricular free wall in 12 open-chest dogs. MAPD90 and transmural dispersion of repolarization among three myocardial layers as well as the incidence of the EAD before autonomic nervous stimulation and during autonomic nervous stimulation were compared. The results showed that the MAPD90 of Epi, Mid and Endo before autonomic nervous stimulation were 278±11 ms,316± 16 ms and 270± 12 ms respectively, the MAPD90of Mid was significantly longer than that of Epi or Endo (P<0.01). MAPD90 of Epi, Mid and Endo were shortened by 19±4 ms, 45±6 ms,18± 3 ms respectively during sympathetic stimulation. Compared with that of the control, the transmural dispersion of repolarization during sympathetic stimulation was shortened from 44 ± 4 ms to 15±3 ms (P<0. 01), but early afterdepolarizations were elicited in the Mid of 5 dogs (41 0%)during sympathetic stimulation. Parasympathetic stimulation did not significantly affect the MAPD90 in the three layers. It is concluded that there is the transmural dispersion of ventricular repolarization in intact canine. Sympathetic stimulation can reduce transmural dispersion of repolarization, but it can produce early afterdepolarizations in the Mid. Parasympathetic stimulation does not significantly affect the transmural dispersion of ventricular repolarization.

  9. Non dominant-negative KCNJ2 gene mutations leading to Andersen-Tawil syndrome with an isolated cardiac phenotype.

    Science.gov (United States)

    Limberg, Maren M; Zumhagen, Sven; Netter, Michael F; Coffey, Alison J; Grace, Andrew; Rogers, Jane; Böckelmann, Doris; Rinné, Susanne; Stallmeyer, Birgit; Decher, Niels; Schulze-Bahr, Eric

    2013-05-01

    Andersen-Tawil syndrome (ATS) is characterized by dysmorphic features, periodic paralyses and abnormal ventricular repolarization. After genotyping a large set of patients with congenital long-QT syndrome, we identified two novel, heterozygous KCNJ2 mutations (p.N318S, p.W322C) located in the C-terminus of the Kir2.1 subunit. These mutations have a different localization than classical ATS mutations which are mostly located at a potential interaction face with the slide helix or at the interface between the C-termini. Mutation carriers were without the key features of ATS, causing an isolated cardiac phenotype. While the N318S mutants regularly reached the plasma membrane, W322C mutants primarily resided in late endosomes. Co-expression of N318S or W322C with wild-type Kir2.1 reduced current amplitudes only by 20-25 %. This mild loss-of-function for the heteromeric channels resulted from defective channel trafficking (W322C) or gating (N318S). Strikingly, and in contrast to the majority of ATS mutations, neither mutant caused a dominant-negative suppression of wild-type Kir2.1, Kir2.2 and Kir2.3 currents. Thus, a mild reduction of native Kir2.x currents by non dominant-negative mutants may cause ATS with an isolated cardiac phenotype.

  10. Meiotic abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-12-31

    Chapter 19, describes meiotic abnormalities. These include nondisjunction of autosomes and sex chromosomes, genetic and environmental causes of nondisjunction, misdivision of the centromere, chromosomally abnormal human sperm, male infertility, parental age, and origin of diploid gametes. 57 refs., 2 figs., 1 tab.

  11. An Electromechanical Left Ventricular Wedge Model to Study the Effects of Deformation on Repolarization during Heart Failure

    Directory of Open Access Journals (Sweden)

    B. M. Rocha

    2015-01-01

    Full Text Available Heart failure is a major and costly problem in public health, which, in certain cases, may lead to death. The failing heart undergo a series of electrical and structural changes that provide the underlying basis for disturbances like arrhythmias. Computer models of coupled electrical and mechanical activities of the heart can be used to advance our understanding of the complex feedback mechanisms involved. In this context, there is a lack of studies that consider heart failure remodeling using strongly coupled electromechanics. We present a strongly coupled electromechanical model to study the effects of deformation on a human left ventricle wedge considering normal and hypertrophic heart failure conditions. We demonstrate through a series of simulations that when a strongly coupled electromechanical model is used, deformation results in the thickening of the ventricular wall that in turn increases transmural dispersion of repolarization. These effects were analyzed in both normal and failing heart conditions. We also present transmural electrograms obtained from these simulations. Our results suggest that the waveform of electrograms, particularly the T-wave, is influenced by cardiac contraction on both normal and pathological conditions.

  12. Role of gap junction channel in the development of beat-to-beat action potential repolarization variability and arrhythmias.

    Science.gov (United States)

    Magyar, Janos; Banyasz, Tamas; Szentandrassy, Norbert; Kistamas, Kornel; Nanasi, Peter P; Satin, Jonathan

    2015-01-01

    The short-term beat-to-beat variability of cardiac action potential duration (SBVR) occurs as a random alteration of the ventricular repolarization duration. SBVR has been suggested to be more predictive of the development of lethal arrhythmias than the action potential prolongation or QT prolongation of ECG alone. The mechanism underlying SBVR is not completely understood but it is known that SBVR depends on stochastic ion channel gating, intracellular calcium handling and intercellular coupling. Coupling of single cardiomyocytes significantly decreases the beat-to-beat changes in action potential duration (APD) due to the electrotonic current flow between neighboring cells. The magnitude of this electrotonic current depends on the intercellular gap junction resistance. Reduced gap junction resistance causes greater electrotonic current flow between cells, and reduces SBVR. Myocardial ischaemia (MI) is known to affect gap junction channel protein expression and function. MI increases gap junction resistance that leads to slow conduction, APD and refractory period dispersion, and an increase in SBVR. Ultimately, development of reentry arrhythmias and fibrillation are associated post-MI. Antiarrhythmic drugs have proarrhythmic side effects requiring alternative approaches. A novel idea is to target gap junction channels. Specifically, the use of gap junction channel enhancers and inhibitors may help to reveal the precise role of gap junctions in the development of arrhythmias. Since cell-to-cell coupling is represented in SBVR, this parameter can be used to monitor the degree of coupling of myocardium.

  13. Longitudinal changes in intracardiac repolarization lability in patients with implantable cardioverter-defibrillator

    Directory of Open Access Journals (Sweden)

    Abhilash eGuduru

    2013-08-01

    Full Text Available Background─While it is known that elevated baseline intracardiac repolarization lability is associated with the risk of fast ventricular tachycardia (FVT /ventricular fibrillation (VF, the effect of its longitudinal changes on the risk of FVT/VF is unknown. Methods and Results─Near-field (NF right ventricular (RV intracardiac electrograms (EGMs were recorded every 3-6 months at rest in 248 patients with structural heart disease (mean age 61.2±13.3; 185[75%] male; 162[65.3%] ischemic cardiomyopathy and implanted cardioverter-defibrillator (ICD or cardiac resynchronization therapy defibrillator (CRT-D [201 (81% primary prevention]. Intracardiac beat-to-beat QT variability index (QTVINF was measured on NF RV EGM. During the first study phase (median 18 months, participants made on average 2.4 visits. Then remote follow-up was continued for an additional median period of 3 years. Average QTVINF did not change during the first year after ICD implantation (-0.342±0.603 at baseline vs. -0.262±0.552 at 6 months vs. -0.334±0.603 at 12 months; however, it decreased thereafter (-0.510±0.603 at 18 months; P=0.042. Adjusted population-averaged GEE model showed that the odds of developing FVT/VF increased by 75% for each 1 unit increase in QTVINF. (OR 1.75 [95%CI 1.05-2.92]; P=0.031. However, individual patient–specific QTVINF trends (increasing, decreasing, flat varied from patient to patient. For a given patient, the odds of developing FVT/VF were not associated with increasing or decreasing QTVINF over time (OR 1.27; [95%CI 0.05–30.10]; P = 0.881.Conclusion─While on average the odds of FVT/VF increased with an increase in QTVINF, patient-specific longitudinal trends in QTVINF did not affect the odds of FVT/VF.

  14. The contribution of ventricular apicobasal and transmural repolarization patterns to the development of the T wave body surface potentials in frogs (Rana temporaria) and pike (Esox lucius).

    Science.gov (United States)

    Vaykshnorayte, Marina A; Azarov, Jan E; Tsvetkova, Alena S; Vityazev, Vladimir A; Ovechkin, Alexey O; Shmakov, Dmitry N

    2011-05-01

    The study aimed at the simultaneous determination of the transmural and apicobasal differences in the repolarization timing and the comparison of the contributions of these two repolarization gradients to the development of the body surface T wave potentials in animals with the single heart ventricle (fishes and amphibians). Unipolar potentials were measured on the body surface, epicardium and in the intramural (subepicardial, Epi; midmyocardial; and subendocardial, Endo) ventricular layers of 9 pike and 8 frogs. Activation times, repolarization times and activation-recovery intervals were determined. A transmural gradient in repolarization durations in frogs (Endo>Epi, Ppike that produces a repolarization sequence from Endo to Epi (Endopike and frogs.

  15. Cardiac manifestations of myotonic dystrophy type 1

    DEFF Research Database (Denmark)

    Petri, Helle; Vissing, John; Witting, Nanna;

    2012-01-01

    To estimate the degree of cardiac involvement regarding left ventricular ejection fraction, conduction abnormalities, arrhythmia, risk of sudden cardiac death (SCD) and the associations between cardiac involvement and cytosine-thymine-guanine (CTG)-repeat, neuromuscular involvement, age and gende...... in patients with myotonic dystrophy type 1 (MD1)....

  16. Correlation between arterial wall stiffness, N-terminal prohormone of brain natriuretic peptide, functional and structural myocardial abnormalities in patients with type 2 diabetes mellitus and cardiac autonomic neuropathy

    Directory of Open Access Journals (Sweden)

    Viktoriya Aleksandrovna Serhiyenko

    2013-12-01

    Full Text Available Aim. To assess arterial wall stiffness, plasma levels of of N-terminal prohormone of brain natriuretic peptide (NT-proBNP, as well as functional state and structure of the myocardium in patients with type 2 diabetes mellitus (T2DM and cardiac autonomic neuropathy (CAN.Materials and Methods. The study involved a total of 65 patients with T2DM. 12 had no evidence of cardiovascular disease (CVD or CAN, 14 were diagnosed with subclinical stage of CAN, 18 – with functional stage, and 21 – with organic stage. We measured aortic pulse wave velocity (PWV, aortic augmentation index (AIx, brachial artery AIx, ambulatory arterial stiffness index (AASI and plasma levels of NT-proBNP. Clinical examination included ECG, Holter monitoring, ambulatory BP measurement and echocardiography.Results. Patients with isolated T2DM showed a trend for increased vascular wall stiffness. PWV was increased in patients with subclinical stage of CAN. Aortic and brachial AIx, PWV and AASI were elevated in patients with functional stage of CAN, PWV being significantly higher vs. subclinical CAN subgroup. Organic stage was characterized by pathologically increased values of all primary parameters; PWV and AASI were significantly higher compared with other groups. Development and progression of CAN was accompanied by an increase in NT-proBNP plasma levels. Concentration of NT-proBNP was in direct correlation with left ventricular mass (LVM and PWV. PWV and LVM values also directly correlated between themselves.Conclusion. Development and progression of CAN in patients with T2DM is accompanied by an increase in vascular wall stiffness. The elevation of plasma NT-proBNP in patients with T2DM correlates with the development of CAN and is significantly and independently associated with an increase in LVM and PWV. Our data suggests the pathophysiological interconnection between metabolic, functional and structural myocardial abnormalities in patients with T2DM and CAN.

  17. Assessment of cardiac sympathetic nerve integrity with positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Raffel, David M. E-mail: raffel@umich.edu; Wieland, Donald M

    2001-07-01

    The autonomic nervous system plays a critical role in the regulation of cardiac function. Abnormalities of cardiac innervation have been implicated in the pathophysiology of many heart diseases, including sudden cardiac death and congestive heart failure. In an effort to provide clinicians with the ability to regionally map cardiac innervation, several radiotracers for imaging cardiac sympathetic neurons have been developed. This paper reviews the development of neuronal imaging agents and discusses their emerging role in the noninvasive assessment of cardiac sympathetic innervation.

  18. Leukocyte abnormalities.

    Science.gov (United States)

    Gabig, T G

    1980-07-01

    Certain qualitative abnormalities in neutrophils and blood monocytes are associated with frequent, severe, and recurrent bacterial infections leading to fatal sepsis, while other qualitative defects demonstrated in vitro may have few or no clinical sequelae. These qualitative defects are discussed in terms of the specific functions of locomotion, phagocytosis, degranulation, and bacterial killing.

  19. Bifid cardiac apex in a 25-year-old male with sudden cardiac death.

    Science.gov (United States)

    Wu, Annie; Kay, Deborah; Fishbein, Michael C

    2014-01-01

    Although a bifid cardiac apex is common in certain marine animals, it is an uncommon finding in humans. When present, bifid cardiac apex is usually associated with other congenital heart anomalies. We present a case of bifid cardiac apex that was an incidental finding in a 25-year-old male with sudden cardiac death from combined drug toxicity. On gross examination, there was a bifid cardiac apex with a 2-cm long cleft. There were no other significant gross or microscopic abnormalities. This case represents the very rare occurrence of a bifid cardiac apex as an isolated cardiac anomaly.

  20. Surface Electrocardiogram Predictors of Sudden Cardiac Arrest

    Science.gov (United States)

    Abdelghani, Samy A.; Rosenthal, Todd M.; Morin, Daniel P.

    2016-01-01

    Background: Heart disease is a major cause of death in industrialized nations, with approximately 50% of these deaths attributable to sudden cardiac arrest. If patients at high risk for sudden cardiac arrest can be identified, their odds of surviving fatal arrhythmias can be significantly improved through prophylactic implantable cardioverter defibrillator placement. This review summarizes the current knowledge pertaining to surface electrocardiogram (ECG) predictors of sudden cardiac arrest. Methods: We conducted a literature review focused on methods of predicting sudden cardiac arrest through noninvasive electrocardiographic testing. Results: Several electrocardiographic-based methods of risk stratification of sudden cardiac arrest have been studied, including QT prolongation, QRS duration, fragmented QRS complexes, early repolarization, Holter monitoring, heart rate variability, heart rate turbulence, signal-averaged ECG, T wave alternans, and T-peak to T-end. These ECG findings have shown variable effectiveness as screening tools. Conclusion: At this time, no individual ECG finding has been found to be able to adequately stratify patients with regard to risk for sudden cardiac arrest. However, one or more of these candidate surface ECG parameters may become useful components of future multifactorial risk stratification calculators. PMID:27660578

  1. Sudden cardiac death risk stratification.

    Science.gov (United States)

    Deyell, Marc W; Krahn, Andrew D; Goldberger, Jeffrey J

    2015-06-01

    Arrhythmic sudden cardiac death (SCD) may be caused by ventricular tachycardia/fibrillation or pulseless electric activity/asystole. Effective risk stratification to identify patients at risk of arrhythmic SCD is essential for targeting our healthcare and research resources to tackle this important public health issue. Although our understanding of SCD because of pulseless electric activity/asystole is growing, the overwhelming majority of research in risk stratification has focused on SCD-ventricular tachycardia/ventricular fibrillation. This review focuses on existing and novel risk stratification tools for SCD-ventricular tachycardia/ventricular fibrillation. For patients with left ventricular dysfunction or myocardial infarction, advances in imaging, measures of cardiac autonomic function, and measures of repolarization have shown considerable promise in refining risk. Yet the majority of SCD-ventricular tachycardia/ventricular fibrillation occurs in patients without known cardiac disease. Biomarkers and novel imaging techniques may provide further risk stratification in the general population beyond traditional risk stratification for coronary artery disease alone. Despite these advances, significant challenges in risk stratification remain that must be overcome before a meaningful impact on SCD can be realized.

  2. Action potential repolarization and a fast after-hyperpolarization in rat hippocampal pyramidal cells.

    Science.gov (United States)

    Storm, J F

    1987-04-01

    1. The repolarization of the action potential, and a fast after-hyperpolarization (a.h.p.) were studied in CA1 pyramidal cells (n = 76) in rat hippocampal slices (28-37 degrees C). Single spikes were elicited by brief (1-3 ms) current pulses, at membrane potentials close to rest (-60 to -70 mV). 2. Each action potential was followed by four after-potentials: (a) the fast a.h.p., lasting 2-5 ms; (b) an after-depolarization; (c) a medium a.h.p., (50-100 ms); and (d) a slow a.h.p. (1-2 s). Both the fast a.h.p. and the slow a.h.p. (but not the medium a.h.p.) were inhibited by Ca2+-free medium or Ca2+-channel blockers (Co2+, Mn2+ or Cd2+); but tetraethylammonium (TEA; 0.5-2 nM) blocked only the fast a.h.p., and noradrenaline (2-5 microM) only the slow a.h.p. This suggests that two Ca2+-activated K+ currents were involved: a fast, TEA-sensitive one (IC) underlying the fast a.h.p., and a slow noradrenaline-sensitive one (IAHP) underlying the slow a.h.p. 3. Like the fast a.h.p., spike repolarization seems to depend on a Ca2+-dependent K+ current of the fast, TEA-sensitive kind (IC). The repolarization was slowed by Ca2+-free medium, Co2+, Mn2+, Cd2+, or TEA, but not by noradrenaline. Charybdotoxin (CTX; 30 nM), a scorpion toxin which blocks the large-conductance Ca2+-activated K+ channel in muscle, had a similar effect to TEA. The effects of TEA and Cd2+ (or Mn2+) showed mutual occlusion. Raising the external K+ concentration reduced the fast a.h.p. and slowed the spike repolarization, whereas Cl- loading of the cell was ineffective. 4. The transient K+ current, IA, seems also to contribute to spike repolarization, because: (a) 4-aminopyridine (4-AP; 0.1 mM), which blocks IA, slowed the spike repolarization; (b) depolarizing pre-pulses, which inactivate IA, had a similar effect; (c) hyperpolarizing pre-pulses speeded up the spike repolarization; (d) the effects of 4-AP and pre-pulses persisted during Ca2+ blockade (like IA); and (e) depolarizing pre-pulses reduced the

  3. Anion channelrhodopsins for inhibitory cardiac optogenetics

    Science.gov (United States)

    Govorunova, Elena G.; Cunha, Shane R.; Sineshchekov, Oleg A.; Spudich, John L.

    2016-01-01

    Optical control of the heart muscle is a promising strategy for cardiology because it is more specific than traditional electrical stimulation, and allows a higher temporal resolution than pharmacological interventions. Anion channelrhodopsins (ACRs) from cryptophyte algae expressed in cultured neonatal rat ventricular cardiomyocytes produced inhibitory currents at less than one-thousandth of the light intensity required by previously available optogenetic tools, such as the proton pump archaerhodopsin-3 (Arch). Because of their greater photocurrents, ACRs permitted complete inhibition of cardiomyocyte electrical activity under conditions in which Arch was inefficient. Most importantly, ACR expression allowed precisely controlled shortening of the action potential duration by switching on the light during its repolarization phase, which was not possible with previously used optogenetic tools. Optical shortening of cardiac action potentials may benefit pathophysiology research and the development of optogenetic treatments for cardiac disorders such as the long QT syndrome. PMID:27628215

  4. Effects of hypokalemia on transmural dispersion of ventricular repolarization in left ventricular myocardium

    Institute of Scientific and Technical Information of China (English)

    Jiang-Hua Zhong; Shi-Juan Lu; Mo-Shui Chen; Zi-Bin Chen; Liu Wang; Ping-Sheng Wu

    2013-01-01

    Objective: To observe effects of hypokalemia on transmural heterogeneity of ventricular repolarization in left ventricular myocardium of rabbit, and explore the role of hypokalemia in malignant ventricular arrhythmia (MVA). Methods: A total of 20 rabbits were randomly divided into control group and hypokalemic group. Isolated hearts in the control group were simply perfused with modified Tyrode's solution, and were perfused with hypokalemic Tyrode's solution in hypokalemic group. Ventricular fibrillation threshold (VFT), 90% monophasic action potential repolarization duration (APD90) of subepicardial, midmyocardial and subendocardial myocardium, transmural dispersion of repolarization (TDR) and Cx43 protein expression in three layers of myocardium were measured in both groups. Results: VFT in the control group and the hypokalemic group were (13.40±2.95) V, and (7.00±1.49) V, respectively. There was a significant difference between two groups (P<0.01). APD90 of three myocardial layers in the hypokalemic group were significantly prolonged than those in the control group (P<0.01). APD90 in the hypokalemic group and the control group were (38.10±10.29) ms and (23.70±5.68) ms, and TDR were (52.90±14.55) ms and (36.10±12.44) ms, respectively. APD90 and TDR in the hypokalemic group were significantly higher than those in the control group (P<0.05), and the increase in APD90 of midmyocardium was more significant in the hypokalemic group. Cx43 protein expression of all three myocardial layers were decreased significantly in the hypokalemic group (P<0.01), and Cx43 was significantly increased (P<0.05). Reduction of Cx43 protein expression was more significant in the midmyocardium. Conclusions: Hypokalemic can increase transmural heterogeneity of Cx43 expression and repolarization in left ventricular myocardium of rabbit, and decrease VFT and can induce MVA more easily.

  5. Differential expression of hERG1 channel isoforms reproduces properties of native I(Kr) and modulates cardiac action potential characteristics

    DEFF Research Database (Denmark)

    Larsen, Anders Peter; Olesen, Søren-Peter

    2010-01-01

    The repolarizing cardiac rapid delayed rectifier current, I(Kr), is composed of ERG1 channels. It has been suggested that two isoforms of the ERG1 protein, ERG1a and ERG1b, both contribute to I(Kr). Marked heterogeneity in the kinetic properties of native I(Kr) has been described. We hypothesized...

  6. Kv3.1 uses a timely resurgent K(+) current to secure action potential repolarization.

    Science.gov (United States)

    Labro, Alain J; Priest, Michael F; Lacroix, Jérôme J; Snyders, Dirk J; Bezanilla, Francisco

    2015-12-17

    High-frequency action potential (AP) transmission is essential for rapid information processing in the central nervous system. Voltage-dependent Kv3 channels play an important role in this process thanks to their high activation threshold and fast closure kinetics, which reduce the neuron's refractory period. However, premature Kv3 channel closure leads to incomplete membrane repolarization, preventing sustainable AP propagation. Here, we demonstrate that Kv3.1b channels solve this problem by producing resurgent K(+) currents during repolarization, thus ensuring enough repolarizing power to terminate each AP. Unlike previously described resurgent Na(+) and K(+) currents, Kv3.1b's resurgent current does not originate from recovery of channel block or inactivation but results from a unique combination of steep voltage-dependent gating kinetics and ultra-fast voltage-sensor relaxation. These distinct properties are readily transferrable onto an orthologue Kv channel by transplanting the voltage-sensor's S3-S4 loop, providing molecular insights into the mechanism by which Kv3 channels contribute to high-frequency AP transmission.

  7. The Effect of a Novel Highly Selective Inhibitor of the Sodium/Calcium Exchanger (NCX) on Cardiac Arrhythmias in In Vitro and In Vivo Experiments

    OpenAIRE

    Kohajda, Zsófia; Farkas-Morvay, Nikolett; Jost, Norbert; Nagy, Norbert; Geramipour, Amir; Horváth, András; Varga, Richárd S.; Hornyik, Tibor; Corici, Claudia; Acsai, Károly; Horváth, Balázs; Prorok, János; Ördög, Balázs; Déri, Szilvia; Tóth, Dániel

    2016-01-01

    Background In this study the effects of a new, highly selective sodium-calcium exchanger (NCX) inhibitor, ORM-10962 were investigated on cardiac NCX current, Ca2+ transients, cell shortening and in experimental arrhythmias. The level of selectivity of the novel inhibitor on several major transmembrane ion currents (L-type Ca2+ current, major repolarizing K+ currents, late Na+ current, Na+/K+ pump current) was also determined. Methods Ion currents in single dog ventricular cells (cardiac myocy...

  8. Anti- or profibrillatory effects of Na+ channel blockade depend on the site of application relative to gradients in repolarization

    Directory of Open Access Journals (Sweden)

    Ruben Coronel

    2010-06-01

    Full Text Available Introduction. Sodium channel blockers are associated with arrhythmic sudden death, although they are considered antiarrhythmic agents. The mechanism of these opposing effects is unknown. Methods. We used a model of induction of ventricular fibrillation (VF based on selective perfusion of the vascular beds of isolated porcine hearts (n=8. One bed was perfused with sotalol (220 µM, the adjacent bed with pinacidil (80 µM, leading to repolarization heterogeneity (late repolarization in the sotalol-, early in the pinacidil-area. Premature stimulation from the area with the short action potential was performed. Epicardial activation/repolarization mapping was done. Results. In 3 of the 8 hearts VF was inducible prior to infusion of flecainide. In those hearts the Fibrillation Factor (FF, the interval between the last activation of the premature beat (S2 in the late repolarizing (sotalol domain and the earliest S2 repolarization in the early repolarizing (pinacidil domain, was significantly shorter than in the hearts without VF (33+/-22 vs 93+/-11 ms, m+/-SEM, p<0.05. In the 3 hearts with VF flecainide was infused in the pinacidil domain after defibrillation. This led to shortening of the line of block, local delay of S2 activation and repolarization, an increase in FF and failure to induce VF. In the 5 hearts without VF, flecainide was subsequently infused in the sotalol domain. This led to a local delay of S2 activation, a shortening of FF (by 47+/- 3 ms and successful induction of VF in 3 hearts. In the 2 remaining hearts FF did not decrease enough (maximally 13 ms to allow reentry. Conclusions Sodium channel blockade applied to myocardium with a short refractory period is antifibrillatory whereas sodium channel blockade of myocardium with a long refractory period is profibrillatory. Our study provides a mechanistic basis for pro- and anti-arrhythmic effects of sodium channel blockers in the absence of structural heart disease.

  9. New aspects of HERG K⁺ channel function depending upon cardiac spatial heterogeneity.

    Directory of Open Access Journals (Sweden)

    Pen Zhang

    Full Text Available HERG K(+ channel, the genetic counterpart of rapid delayed rectifier K(+ current in cardiac cells, is responsible for many cases of inherited and drug-induced long QT syndromes. HERG has unusual biophysical properties distinct from those of other K(+ channels. While the conventional pulse protocols in patch-clamp studies have helped us elucidate these properties, their limitations in assessing HERG function have also been progressively noticed. We employed AP-clamp techniques using physiological action potential waveforms recorded from various regions of canine heart to study HERG function in HEK293 cells and identified several novel aspects of HERG function. We showed that under AP-clamp IHERG increased gradually with membrane repolarization, peaked at potentials around 20-30 mV more negative than revealed by pulse protocols and at action potential duration (APD to 60%-70% full repolarization, and fell rapidly at the terminal phase of repolarization. We found that the rising phase of IHERG was conferred by removal of inactivation and the decaying phase resulted from a fall in driving force, which were all determined by the rate of membrane repolarization. We identified regional heterogeneity and transmural gradient of IHERG when quantified with the area covered by IHERG trace. In addition, we observed regional and transmural differences of IHERG in response to dofetilide blockade. Finally, we characterized the influence of HERG function by selective inhibition of other ion currents. Based on our results, we conclude that the distinct biophysical properties of HERG reported by AP-clamp confer its unique function in cardiac repolarization thereby in antiarrhythmia and arrhythmogenesis.

  10. 瓜蒌薤白半夏汤对不稳定性心绞痛心脏室壁运动的影响%The effects of gualouxiebaibanxia decoction on the cardiac ventricular wall motion abnormalities in unstable angina pectoris

    Institute of Scientific and Technical Information of China (English)

    林培森

    2012-01-01

    目的观察瓜蒌薤白半夏汤对不稳定性心绞痛(UAP)心脏室壁运动异常的疗效.方法将120例经心彩超证实有心脏室壁运动异常的UAP患者随机分为治疗组与对照组,每组各60例.对照组采用常规的西药治疗,治疗组在西药治疗基础上加用瓜蒌薤白半夏汤,疗程均为1个月.结果与对照组比较,治疗组在缓解心绞痛发作方面的有效率优于对照组(93.3% VS 83.3%),治疗组在胸痹证候改善方面的有效率也优于对照组(86.6% VS 73.3%),治疗组在改善心电图方面的有效率也优于对照组(81.6% VS 63.3%),治疗组在改善心脏室壁运动异常的有效率也优于对照组(78.3% VS 65%),差异均有显著性意义(P<0.05).结论应用瓜蒌薤白半夏汤治疗UAP疗效确切,可明显改善心电图及心脏室壁运动异常.%Objective: To observe the curative effects of gualouxiebaibanxia decoction on the cardiac ventricular wall motion abnormalities in unstable angina pectoris. Methods: 120 cases of patients with ustable angina pectoris and cardiac ventricular wall motion abnormalities were randomly divided into two groups, treatment group and control group, 60 cases in each group. Control group was treated with western medicine and treatment group with gualouxiebaibanxia decoction and western medicine for one month. Results: Compared with the control group, the efficacy of treatment group was better in relieving angina pectoris(81.6% VS 63.3%), improving chest syndrome(86.6% VS 73.3%), improving electrocardiograph (81.6% VS 63.3%), and improving cardiac ventricular wall motion abnormalities(78.3% VS 65%). The differences were significant (P <0.05). Conclusion: It is effective that treating unstable angina pectoris with gualouxiebaibanxia decoction, which can significantly improve electrocardiograph and cardiac ventricular wall motion abnormalities.

  11. Cardiac arrest

    Science.gov (United States)

    ... Article.jsp. Accessed June 16, 2014. Myerburg RJ, Castellanos A. Approach to cardiac arrest and life-threatening ... PA: Elsevier Saunders; 2011:chap 63. Myerburg RJ, Castellanos A. Cardiac arrest and audden aardiac death. In: ...

  12. Archaerhodopsin voltage imaging: synaptic calcium and BK channels stabilize action potential repolarization at the Drosophila neuromuscular junction.

    Science.gov (United States)

    Ford, Kevin J; Davis, Graeme W

    2014-10-29

    The strength and dynamics of synaptic transmission are determined, in part, by the presynaptic action potential (AP) waveform at the nerve terminal. The ion channels that shape the synaptic AP waveform remain essentially unknown for all but a few large synapses amenable to electrophysiological interrogation. The Drosophila neuromuscular junction (NMJ) is a powerful system for studying synaptic biology, but it is not amenable to presynaptic electrophysiology. Here, we demonstrate that Archaerhodopsin can be used to quantitatively image AP waveforms at the Drosophila NMJ without disrupting baseline synaptic transmission or neuromuscular development. It is established that Shaker mutations cause a dramatic increase in neurotransmitter release, suggesting that Shaker is predominantly responsible for AP repolarization. Here we demonstrate that this effect is caused by a concomitant loss of both Shaker and slowpoke (slo) channel activity because of the low extracellular calcium concentrations (0.2-0.5 mM) used typically to assess synaptic transmission in Shaker. In contrast, at physiological extracellular calcium (1.5 mM), the role of Shaker during AP repolarization is limited. We then provide evidence that calcium influx through synaptic CaV2.1 channels and subsequent recruitment of Slo channel activity is important, in concert with Shaker, to ensure proper AP repolarization. Finally, we show that Slo assumes a dominant repolarizing role during repetitive nerve stimulation. During repetitive stimulation, Slo effectively compensates for Shaker channel inactivation, stabilizing AP repolarization and limiting neurotransmitter release. Thus, we have defined an essential role for Slo channels during synaptic AP repolarization and have revised our understanding of Shaker channels at this model synapse.

  13. Athletes at Risk for Sudden Cardiac Death

    Science.gov (United States)

    Subasic, Kim

    2010-01-01

    High school athletes represent the largest group of individuals affected by sudden cardiac death, with an estimated incidence of once or twice per week. Structural cardiovascular abnormalities are the most frequent cause of sudden cardiac death. Athletes participating in basketball, football, track, soccer, baseball, and swimming were found to…

  14. [Andersen-Tawil syndrome: a review of its clinical and genetic diagnosis with emphasis on cardiac manifestations].

    Science.gov (United States)

    Márquez, Manlio F; Totomoch-Serra, Armando; Vargas-Alarcón, Gilberto; Cruz-Robles, David; Pellizzon, Oscar A; Cárdenas, Manuel

    2014-01-01

    The Andersen-Tawil syndrome is a cardiac ion channel disease that is inherited in an autosomal dominant way and is classified as type 7 of the congenital long QT syndromes. Affected gene is KCNJ2, which forms the inward rectifier potassium channel designated Kir2.1. This protein is involved in stabilizing the resting membrane potential and controls the duration of the action potential in skeletal muscle and heart. It also participates in the terminal repolarization phase of the action potential in ventricular myocytes and is a major component responsible for the correction in the potassium current during phase 3 of the action potential repolarization. Kir 2.1 channel has a predominant role in skeletal muscle, heart and brain. Alterations in this channel produce flaccid paralysis, arrhythmias, impaired skeletal development primarily in extremities and facial area. In this review we address the disease from the point of view of clinical and molecular diagnosis with emphasis on cardiac manifestations.

  15. 中期孕妇胎儿心脏畸形超声心动图表现与染色体异常的相关性%Correlation between fetal cardiac malformations echocardiography and chromosomal abnormalities in mid-pregnancy

    Institute of Scientific and Technical Information of China (English)

    陈兵勇; 尹晓云; 陈婕; 黄继才; 李景珊

    2015-01-01

    Objective To explore the correlation between fetal cardiac malformations echocardiography and chromosomal abnormalities in mid-pregnancy. Methods A total of 5 000 cases of women in mid-pregnancy in our hospital from March 2012 to December 2014 who received prenatal ultrasound and karyotype examination were in-cluded in the study. And correlation between fetal cardiac malformations echocardiography and chromosomal abnor-malities was analyzed. Results In 60 fetal cardiac malformation cases, there were 16 chromosomal abnormalities cas-es which accounting for 26.67%(16/60), including 1 case of X monomer, 3 cases of trisomy 13, 7 cases of trisomy 18, and 5 cases of trisomy 21. While in 16 fetal congenital heart disease (CHD) cases, all X monomer and trisomy 13 cas-es, 60%of trisomy 21 cases and 85.71%of trisomy 18 cases were found with varying degrees of extracardiac malfor-mations. Conclusion Fetal cardiac malformations are closely related with chromosomal abnormalities. Therefore malformations should be carefully considered if fetal cardiac malformations were found in ultrasound screening, and a chromosome examination would be clinically recommended.%目的:检测中期孕妇胎儿心脏畸形超声心动图与染色体异常变异,探讨其可能存在的关系。方法对本院2012年3月至2014年12月收治的5000例中期孕妇进行产前超声与染色体核型检查,综合比较分析胎儿心脏畸形超声心动图表现和染色体异常的关系。结果60例心脏畸形胎儿确诊病例中伴染色体异常者16例,占26.67%(16/60),其中X单体1例,13-三体3例,18-三体7例,21-三体5例。16例先天性心脏病(CHD)胎儿中,全部的X单体和13-三体、60%的21-三体以及85.71%的18-三体患儿均伴有不同程度的心外器官的畸形。结论胎儿心脏结构畸形与染色体异常关系密切,产前超声筛查发现心脏畸形时应仔细检查胎儿是否合并心外系统畸形,并结合临床筛查指标建议行染色体检查。

  16. Fetal cardiac rhabdomyoma: case report

    Directory of Open Access Journals (Sweden)

    Seyed Mostafa Ghavami

    2016-07-01

    Full Text Available Background: The primary manifestation of cardiac tumors in embryonic period is a very rare condition. Cardiac rhabdomyomas most frequently arise in the ventricular myocardium, they may also occur in the atria and the epicardial surface. In spite of its benign nature, the critical location of the tumor inside the heart can lead to lethal arrhythmias and chamber obstruction. Multiple rhabdomyomas are strongly associated with tuberous sclerosis which is associated with mental retardation and epilepsy of variable severity. Ultrasonography as a part of routine prenatal screening, is the best method for the diagnosis of cardiac rhabdomyomas. In the review of articles published in Iran, fetal cardiac rhabdomyoma was not reported. Case presentation: We report a case of cardiac rhabdomyoma on a 24-year-old gravid 1, referred to Day Medical Imaging Center for routine evaluation of fetal abnormalities at 31 weeks of her gestational age. Ultrasonographic examination displayed a homogenous echogenic mass (13×9mm, originating from the left ventricle of the fetal heart. It was a normal pregnancy without any specific complications. Other organs of the fetus were found normal and no cardiac abnormalities were appeared. No Pericardial fluid effusion was found. The parents did not have consanguineous marriage. They did not also have any specific disease such as tuberous sclerosis. Conclusion: The clinical features of cardiac rhabdomyomas vary widely, depending on the location, size, and number of tumors in the heart. Although cardiac rhabdomyoma is a benign tumor in many affected fetuses, an early prenatal diagnosis of the tumor is of great significance in making efficient planning and providing adequate follow up visits of the patients and the complications such as, heart failure and outlet obstruction of cardiac chambers.

  17. Local Left Ventricular Epicardial J Waves and Late Potentials in Brugada Syndrome Patients with Inferolateral Early Repolarization Pattern.

    Science.gov (United States)

    Nagase, Satoshi; Tanaka, Masamichi; Morita, Hiroshi; Nakagawa, Koji; Wada, Tadashi; Murakami, Masato; Nishii, Nobuhiro; Nakamura, Kazufumi; Ito, Hiroshi; Ohe, Tohru; Kusano, Kengo F

    2017-01-01

    Background: Brugada syndrome (BrS) is characterized by J-point or ST-segment elevation on electrocardiograms (ECGs) and increased risk of ventricular fibrillation (VF). In BrS, epicardial depolarization abnormality with delayed potential on the right ventricular outflow tract is reportedly the predominant mechanism underlying VF. Yet VF occurrence is also associated with early repolarization (ER) pattern in the inferolateral ECG leads, which may represent the inferior and/or left lateral ventricular myocardium. The aim of this study was to examine epicardial electrograms recorded directly at the left ventricle (LV) in BrS patients after VF episodes. Methods: In 12 BrS patients who had experienced VF episodes and 17 control subjects, a multipolar catheter was introduced into the left lateral coronary vein for unipolar and bipolar electrogram recordings at the LV epicardium. Both inferior and lateral ER patterns on ECG were observed in three BrS patients and six control subjects. Results: In the epicardium, prominent J waves were detected using unipolar recording, and potentials after the QRS complex were detected using bipolar recording in three of the 12 BrS patients. These three patients also showed both inferior and lateral ER patterns on ECG. Neither prominent J waves nor potentials after the QRS complex were recorded at the endocardium of the LV in any of these three patients; nor were they seen at the epicardium in any of the control subjects. These features were accentuated on pilsicainide administration (n = 2) but diminished on constant atrial pacing (n = 3) and isoproterenol administration (n = 1). The J waves observed through unipolar recording coincided with the potentials after QRS complex observed through bipolar recording and with the inferolateral ER patterns on ECG. Conclusions: We recorded prominent J waves in unipolar electrogram and potentials after QRS complex in bipolar electrogram at the LV epicardium in BrS patients with global ER pattern

  18. Local Left Ventricular Epicardial J Waves and Late Potentials in Brugada Syndrome Patients with Inferolateral Early Repolarization Pattern

    Science.gov (United States)

    Nagase, Satoshi; Tanaka, Masamichi; Morita, Hiroshi; Nakagawa, Koji; Wada, Tadashi; Murakami, Masato; Nishii, Nobuhiro; Nakamura, Kazufumi; Ito, Hiroshi; Ohe, Tohru; Kusano, Kengo F.

    2017-01-01

    Background: Brugada syndrome (BrS) is characterized by J-point or ST-segment elevation on electrocardiograms (ECGs) and increased risk of ventricular fibrillation (VF). In BrS, epicardial depolarization abnormality with delayed potential on the right ventricular outflow tract is reportedly the predominant mechanism underlying VF. Yet VF occurrence is also associated with early repolarization (ER) pattern in the inferolateral ECG leads, which may represent the inferior and/or left lateral ventricular myocardium. The aim of this study was to examine epicardial electrograms recorded directly at the left ventricle (LV) in BrS patients after VF episodes. Methods: In 12 BrS patients who had experienced VF episodes and 17 control subjects, a multipolar catheter was introduced into the left lateral coronary vein for unipolar and bipolar electrogram recordings at the LV epicardium. Both inferior and lateral ER patterns on ECG were observed in three BrS patients and six control subjects. Results: In the epicardium, prominent J waves were detected using unipolar recording, and potentials after the QRS complex were detected using bipolar recording in three of the 12 BrS patients. These three patients also showed both inferior and lateral ER patterns on ECG. Neither prominent J waves nor potentials after the QRS complex were recorded at the endocardium of the LV in any of these three patients; nor were they seen at the epicardium in any of the control subjects. These features were accentuated on pilsicainide administration (n = 2) but diminished on constant atrial pacing (n = 3) and isoproterenol administration (n = 1). The J waves observed through unipolar recording coincided with the potentials after QRS complex observed through bipolar recording and with the inferolateral ER patterns on ECG. Conclusions: We recorded prominent J waves in unipolar electrogram and potentials after QRS complex in bipolar electrogram at the LV epicardium in BrS patients with global ER pattern

  19. Ventricular repolarization time, location of pacing stimulus and current pulse amplitude conspire to determine arrhythmogenicity in mice

    DEFF Research Database (Denmark)

    Speerschneider, T; Grubb, Søren Jahn; Olesen, S P;

    2016-01-01

    AIM: In this study, we investigate the impact of altered action potential durations (APD) on ventricular repolarization time and proarrhythmia in mice with and without genetic deletion of the K(+) -channel-interacting protein 2 (KChIP2(-/-) and WT respectively). Moreover, we examine...

  20. Attenuated ventricular β-adrenergic response and reduced repolarization reserve in a rabbit model of chronic heart failure

    DEFF Research Database (Denmark)

    Nissen, Jakob Dahl; Thomsen, Morten Bækgaard; Bentzen, Bo Hjorth

    2012-01-01

    mortality but profound structural, functional, and electrical remodeling and compare with nonpaced controls. Pacing increased heart weight/body weight ratio and decreased left ventricular fractional shortening in tachypaced only. Electrocardiogram recordings during sinus rhythm revealed QTc prolongation...... remodeling but very low mortality. Isokalemic and hyperkalemic responses indicate downregulation of functional IKs. Increased short-term variability during hypokalemia unmasks a reduced repolarization reserve....

  1. The relationship of non-sustained ventricular tachycardia and cardiac death in patients with congestive heart failure%充血性心力衰竭患者非持续性室性心动过速与心脏性死亡的关系

    Institute of Scientific and Technical Information of China (English)

    罗昭林; 何作云; 钟杭美

    2000-01-01

    目的:探讨充血性心力衰竭(CHF)患者非持续性室性心动过速(NSVT)与心脏性死亡之间的关系。方法:对52例CHF伴NSVT患者,根据住院期间是否发生心脏性死亡,分为死亡组(13例),存活组(39例),分析两组心电图及临床特征。结果:死亡组NSVT的发作阵数高,频率快,每阵持续搏动数多,QRS波时限宽,多形性VT发生率高(P0.05),但死亡组左室射血分数明显低于存活组(P0.05). The left ventricular ejection fraction was lower in cardiac death group than in survivor group( P<0.001). Conclusion:The higher episodes in 24 hours,the faster rate, the more beats in episodes,the longer duration of QRS complex wave of VT,especially the patients with polymorphic VT and ventricular depolarization and repolarization abnormal are in higher danger of cardiac death.

  2. 糖耐量异常对冠心病支架植入术后主要心脏事件的影响%Impact of abnormal glucose metabolism on major adverse cardiac event in patients after coronary artery gent implantation

    Institute of Scientific and Technical Information of China (English)

    纪军; 何胜虎

    2008-01-01

    目的 探讨糖耐量异常对冠心病支架植入术后冠心病患者主要心脏事件的影响.方法 215例冠状动脉造影资料齐全的支架术后的患者,分为合并2型糖尿病(2-DM)组(A组)、糖耐量异常组(B组)、糖代谢正常组(NDM)(C组),比较三组在住院期间和随访期间发生典型心绞痛、非致死性心肌梗死、心源性死亡和靶血管重建等主要心脏事件(MACE)的发生率.结果 A组与B组主要心脏事件发生率显著高于C组(P<0.01);A组与B组间差异无统计学意义;A组再狭窄发生率高于B组(P<0.01).结论 冠心病合并糖耐量异常患者与冠心病合并糖尿病患者一样,有较高的心脏事件发生率,故对合并糖耐量异常的冠心病患者应及早干预,积极控制血糖.%Objective To investigate impact of abnormal slucose metabolism on major adverse cardiac event in patients after coronary artery stent implantation.Methods Two hundred and fifteen patients whose data were available were enrolled in this study,and the patients were divided into 3 groups,diabetes group(group A),abnormal glucose metabolism group(group B),normal glucose tolerance group(group C).The clinica,coronary artery lesion characteristics and major adverse cardiac event(MACE)rate during in hospital and follow up periods were compared.Resuits There was a higher occurrence of MACE in group A and group B than that in group C(P<0.01).There was no significant difference between group A and group B.Conclusion The patients of coronary heart disease with abnormal slucose metabolism have higher MACE rate than abnormal slueese metabolism.

  3. Clinical frontiers in electrocardiographic early repolarization syndrome: does a good guy turn bad now?

    Institute of Scientific and Technical Information of China (English)

    Xingpeng Liu; Ashok Shah; Frédéric Sacher; Nicolas Derval; Amir S. Jadidi; Mélèze Hocini; Michel Haissaguerre

    2010-01-01

    @@ Early repolarization pattern (ERP) is a common electrocardiographic (ECG) variant, characterized by J point elevation manifested either as QRS slurring (at the transition from the QRS segment to the ST segment) or notching (a positive deflection inscribed on terminal S wave), ST-segment elevation with upper concavity and prominent T waves in at least two contiguous leads.1,2 The prevalence of ERP in normal population varies from 1 % to 13%, depending on the age (predominant in young adults), the race (highest amongst black population), and the criterion for J point elevation (0.05 mV vs. 0.1 mV).3-7 In addition, higher incidence of ERP exists in males, athletes and individuals with high vagal tone or selective loss of sympathetic tone (e.g. spinal cord injury).8

  4. A Principal Component Regression Approach for Estimating Ventricular Repolarization Duration Variability

    Directory of Open Access Journals (Sweden)

    Pasi A. Karjalainen

    2007-01-01

    Full Text Available Ventricular repolarization duration (VRD is affected by heart rate and autonomic control, and thus VRD varies in time in a similar way as heart rate. VRD variability is commonly assessed by determining the time differences between successive R- and T-waves, that is, RT intervals. Traditional methods for RT interval detection necessitate the detection of either T-wave apexes or offsets. In this paper, we propose a principal-component-regression- (PCR- based method for estimating RT variability. The main benefit of the method is that it does not necessitate T-wave detection. The proposed method is compared with traditional RT interval measures, and as a result, it is observed to estimate RT variability accurately and to be less sensitive to noise than the traditional methods. As a specific application, the method is applied to exercise electrocardiogram (ECG recordings.

  5. Cardiac strength-interval curves calculated using a bidomain tissue with a parsimonious ionic current

    Science.gov (United States)

    Roth, Bradley J.

    2017-01-01

    The strength-interval curve plays a major role in understanding how cardiac tissue responds to an electrical stimulus. This complex behavior has been studied previously using the bidomain formulation incorporating the Beeler-Reuter and Luo-Rudy dynamic ionic current models. The complexity of these models renders the interpretation and extrapolation of simulation results problematic. Here we utilize a recently developed parsimonious ionic current model with only two currents—a sodium current that activates rapidly upon depolarization INa and a time-independent inwardly rectifying repolarization current IK—which reproduces many experimentally measured action potential waveforms. Bidomain tissue simulations with this ionic current model reproduce the distinctive dip in the anodal (but not cathodal) strength-interval curve. Studying model variants elucidates the necessary and sufficient physiological conditions to predict the polarity dependent dip: a voltage and time dependent INa, a nonlinear rectifying repolarization current, and bidomain tissue with unequal anisotropy ratios. PMID:28222136

  6. Hepato-cardiac disorders

    Institute of Scientific and Technical Information of China (English)

    Yasser; Mahrous; Fouad; Reem; Yehia

    2014-01-01

    Understanding the mutual relationship between the liver and the heart is important for both hepatologists and cardiologists. Hepato-cardiac diseases can be classified into heart diseases affecting the liver, liver diseases affecting the heart, and conditions affecting the heart and the liver at the same time. Differential diagnoses of liver injury are extremely important in a cardiologist’s clinical practice calling for collaboration between cardiologists and hepatologists due to the many other diseases that can affect the liver and mimic haemodynamic injury. Acute and chronic heart failure may lead to acute ischemic hepatitis or chronic congestive hepatopathy. Treatment in these cases should be directed to the primary heart disease. In patients with advanced liver disease, cirrhotic cardiomyopathy may develop including hemodynamic changes, diastolic and systolic dysfunctions, reduced cardiac performance and electrophysiological abnormalities. Cardiac evaluation is important for patients with liver diseases especially before and after liver transplantation. Liver transplantation may lead to the improvement of all cardiac changes and the reversal of cirrhotic cardiomyopathy. There are systemic diseases that may affect both the liver and the heart concomitantly including congenital, metabolic and inflammatory diseases as well as alcoholism. This review highlights these hepatocardiac diseases

  7. Prognostic Value of a New Marker of Ventricular Repolarization in Cirrhotic Patients

    Science.gov (United States)

    Salgado, Angelo Antunes; Barbosa, Paulo Roberto Benchimol; Ferreira, Alinne Gimenez; Reis, Camila Aparecida de Souza Segrégio; Terra, Carlos

    2016-01-01

    Background There is still debate about the relationship between changes in ventricular repolarization on the surface electrocardiogram and cirrhosis severity. Objective To study the relationship between variables related to ventricular repolarization and the clinical severity of the cirrhotic disease. Methods We selected 79 individuals with hepatic cirrhosis, classified according to the Child-Pugh-Turcotte criteria (Child A, B, and C). We measured the QT and corrected QT (QTc) intervals, and the interval between the peak and the end of the T wave (TpTe), and we identified their minimum, maximum, and mean values in the 12-lead electrocardiogram. We also calculated the dispersion of the QT (DQT) and QTc (DQTc) intervals. Results In 12 months of clinical follow-up, nine subjects underwent hepatic transplantation (Child A: 0 [0%]; Child B: 6 [23.1%]; Child C: 3 [18.8%]; p = 0.04) and 12 died (Child A: 3 [12.0%]; Child B: 4 [15.4%]; Child C: 5 [31.3%]; p = 0.002). No significant differences were observed between the cirrhotic groups related to the minimum, maximum, and mean values for the QT, QTc, TpTe, DQT, and DQTc intervals. A minimum TpTe interval ≤ 50 ms was a predictor for the composite endpoints of death or liver transplantation with a sensitivity of 90% and a specificity of 57% (p = 0.005). In the Cox multivariate analysis, the Child groups and a minimum TpTe of ≤ 50 ms were independent predictors of the composite endpoints. Conclusion The intervals QT, QTc, DQT, DQTc, and TpTe have similar distributions between different severity stages in cirrhotic disease. The TpTe interval proved to be a prognostic marker in subjects with cirrhosis, regardless of disease severity (NCT01433848).

  8. Cardiac Malpositions

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Shi Joon; Im, Chung Gie; Yeon, Kyung Mo; Hasn, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1979-06-15

    Cardiac Malposition refers to any position of the heart other than a left-sided heart in a situs solitus individual. Associated cardiac malformations are so complex that even angiocardiographic and autopsy studies may not afford an accurate information. Although the terms and classifications used to describe the internal cardiac anatomy and their arterial connections in cardiac malpositions differ and tend to be confusing, common agreement exists on the need for a segmental approach to diagnosis. Authors present 18 cases of cardiac malpositions in which cardiac catheterization and angiocardiography were done at the Department of Radiology, Seoul National University Hospital between 1971 and 1979. Authors analyzed the clinical, radiographic, operative and autopsy findings with the emphasis on the angiocardiographic findings. The results are as follows: 1. Among 18 cases with cardiac malpositions, 6 cases had dextrocardia with situs inversus, 9 cases had dextrocardia with situs solitus and 3 cases had levocardia with situs inversus. 2. There was no genuine exception to visceroatrial concordance rule. 3. Associated cardiac malpositions were variable and complex with a tendency of high association of transposition and double outlet varieties with dextrocardia in situs solitus and levocardia in situs inversus. Only one in 6 cases of dextrocardia with situs inversus had pure transposition. 4. In two cases associated pulmonary atresia was found at surgery which was not predicted by angiocardiography. 5. Because many of the associated complex lesions can be corrected surgically provided the diagnosis is accurate, the selective biplane angiocardiography with or without cineradiography is essential.

  9. Processing and analysis of cardiac optical mapping data obtained with potentiometric dyes.

    Science.gov (United States)

    Laughner, Jacob I; Ng, Fu Siong; Sulkin, Matthew S; Arthur, R Martin; Efimov, Igor R

    2012-10-01

    Optical mapping has become an increasingly important tool to study cardiac electrophysiology in the past 20 years. Multiple methods are used to process and analyze cardiac optical mapping data, and no consensus currently exists regarding the optimum methods. The specific methods chosen to process optical mapping data are important because inappropriate data processing can affect the content of the data and thus alter the conclusions of the studies. Details of the different steps in processing optical imaging data, including image segmentation, spatial filtering, temporal filtering, and baseline drift removal, are provided in this review. We also provide descriptions of the common analyses performed on data obtained from cardiac optical imaging, including activation mapping, action potential duration mapping, repolarization mapping, conduction velocity measurements, and optical action potential upstroke analysis. Optical mapping is often used to study complex arrhythmias, and we also discuss dominant frequency analysis and phase mapping techniques used for the analysis of cardiac fibrillation.

  10. International Conference on Harmonisation; guidance on S7B Nonclinical Evaluation of the Potential for Delayed Ventricular Repolarization (QT Interval Prolongation) by Human Pharmaceuticals; availability. Notice.

    Science.gov (United States)

    2005-10-20

    The Food and Drug Administration (FDA) is announcing the availability of a guidance entitled "S7B Nonclinical Evaluation of the Potential for Delayed Ventricular Repolarization (QT Interval Prolongation) by Human Pharmaceuticals." The guidance was prepared under the auspices of the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH). The guidance describes a nonclinical testing strategy for assessing the potential of a test substance to delay ventricular repolarization and includes information concerning nonclinical assays and an integrated risk assessment. The guidance is intended to facilitate the nonclinical assessment of the effects of pharmaceuticals on ventricular repolarization and proarrhythmic risk.

  11. Mouse ECG findings in aging, with conduction system affecting drugs and in cardiac pathologies: Development and validation of ECG analysis algorithm in mice.

    Science.gov (United States)

    Merentie, Mari; Lipponen, Jukka A; Hedman, Marja; Hedman, Antti; Hartikainen, Juha; Huusko, Jenni; Lottonen-Raikaslehto, Line; Parviainen, Viktor; Laidinen, Svetlana; Karjalainen, Pasi A; Ylä-Herttuala, Seppo

    2015-12-01

    Mouse models are extremely important in studying cardiac pathologies and related electrophysiology, but very few mouse ECG analysis programs are readily available. Therefore, a mouse ECG analysis algorithm was developed and validated. Surface ECG (lead II) was acquired during transthoracic echocardiography from C57Bl/6J mice under isoflurane anesthesia. The effect of aging was studied in young (2-3 months), middle-aged (14 months) and old (20-24 months) mice. The ECG changes associated with pharmacological interventions and common cardiac pathologies, that is, acute myocardial infarction (AMI) and progressive left ventricular hypertrophy (LVH), were studied. The ECG raw data were analyzed with an in-house ECG analysis program, modified specially for mouse ECG. Aging led to increases in P-wave duration, atrioventricular conduction time (PQ interval), and intraventricular conduction time (QRS complex width), while the R-wave amplitude decreased. In addition, the prevalence of arrhythmias increased during aging. Anticholinergic atropine shortened PQ time, and beta blocker metoprolol and calcium-channel blocker verapamil increased PQ interval and decreased heart rate. The ECG changes after AMI included early JT elevation, development of Q waves, decreased R-wave amplitude, and later changes in JT/T segment. In progressive LVH model, QRS complex width was increased at 2 and especially 4 weeks timepoint, and also repolarization abnormalities were seen. Aging, drugs, AMI, and LVH led to similar ECG changes in mice as seen in humans, which could be reliably detected with this new algorithm. The developed method will be very useful for studies on cardiovascular diseases in mice.

  12. G-protein-coupled inward rectifier potassium current contributes to ventricular repolarization

    DEFF Research Database (Denmark)

    Liang, Bo; Nissen, Jakob D; Laursen, Morten;

    2014-01-01

    The purpose of this study was to investigate the functional role of G-protein-coupled inward rectifier potassium (GIRK) channels in the cardiac ventricle.......The purpose of this study was to investigate the functional role of G-protein-coupled inward rectifier potassium (GIRK) channels in the cardiac ventricle....

  13. Andersen syndrome: an association of periodic paralysis, cardiac arrhythmia and dysmorphic abnormalities Síndrome de Andersen: uma associação de paralisia periódica com arritmia cardíaca e alterações dismórficas

    Directory of Open Access Journals (Sweden)

    Célia H. Tengan

    2006-09-01

    Full Text Available Andersen syndrome (AS is a rare disease characterized by the presence of periodic paralysis (PP, cardiac arrhythmia and dysmorphic abnormalities. We report herein the first Brazilian patient presenting AS who also had obesity, obstructive sleep apnea (OSA and daytime sleepiness. Clinical and genetic evaluation of six family members demonstrated that four had dysmorphic abnormalities but none had PP or cardiac arrhythmia. Sequencing of KCNJ2 revealed the R218W mutation in the index patient and her 6-year-old daughter, who presented dysmorphic abnormalities (micrognathia, clinodactyly of fourth and fifth fingers, short stature and OSA. Three relatives had clinodactyly as the only manifestation but the R218W mutation was absent, suggesting that this characteristic may be influenced by another gene. OSA accompanied by dysmorphic features may be related to AS.A síndrome de Andersen (SA é doença rara caracterizada pela presença de paralisia periódica (PP, arritmia cardíaca e anormalidades dismórficas. Relatamos o primeiro paciente brasileiro apresentando SA, e que também apresenta obesidade e apnéia obstrutiva do sono (AOS. Avaliações clínica e genética de seis familiares demonstraram que quatro apresentavam alterações dismórficas mas nenhum tinha PP ou arritmia cardíaca. O sequenciamento do gene KCNJ2 revelou a mutação R218W no paciente índex e sua filha de 6 anos, que apresentava alterações dismórficas (micrognatia, clinodactilia do quarto e quinto dedos, baixa estatura e AOS. Três familiares tinham clinodactilia como única manifestação mas a mutação R218W estava ausente, sugerindo que esta característica seja influenciada por outro gene. A AOS associada a alterações dismórficas pode estar relacionada à SA.

  14. Reduced Right Ventricular Function Predicts Long-Term Cardiac Re-Hospitalization after Cardiac Surgery.

    Directory of Open Access Journals (Sweden)

    Leela K Lella

    Full Text Available The significance of right ventricular ejection fraction (RVEF, independent of left ventricular ejection fraction (LVEF, following isolated coronary artery bypass grafting (CABG and valve procedures remains unknown. The aim of this study is to examine the significance of abnormal RVEF by cardiac magnetic resonance (CMR, independent of LVEF in predicting outcomes of patients undergoing isolated CABG and valve surgery.From 2007 to 2009, 109 consecutive patients (mean age, 66 years; 38% female were referred for pre-operative CMR. Abnormal RVEF and LVEF were considered 30 days outcomes included, cardiac re-hospitalization, worsening congestive heart failure and mortality. Mean clinical follow up was 14 months.Forty-eight patients had reduced RVEF (mean 25% and 61 patients had normal RVEF (mean 50% (p<0.001. Fifty-four patients had reduced LVEF (mean 30% and 55 patients had normal LVEF (mean 59% (p<0.001. Patients with reduced RVEF had a higher incidence of long-term cardiac re-hospitalization vs. patients with normal RVEF (31% vs.13%, p<0.05. Abnormal RVEF was a predictor for long-term cardiac re-hospitalization (HR 3.01 [CI 1.5-7.9], p<0.03. Reduced LVEF did not influence long-term cardiac re-hospitalization.Abnormal RVEF is a stronger predictor for long-term cardiac re-hospitalization than abnormal LVEF in patients undergoing isolated CABG and valve procedures.

  15. Abnormal echocardiography in patients with type 2 diabetes and relation to symptoms and clinical characteristics

    DEFF Research Database (Denmark)

    Jørgensen, Peter Godsk; Jensen, Magnus T; Mogelvang, Rasmus;

    2016-01-01

    OBJECTIVES: We aimed to determine the prevalence of echocardiographic abnormalities and their relation to clinical characteristics and cardiac symptoms in a large, contemporary cohort of patients with type 2 diabetes. RESULTS: A total of 1030 patients with type 2 diabetes participated...... with abnormal echocardiography along with dyspnoea and characteristic chest pain (p characteristics had sufficient sensitivity and specificity to accurately identify patients with abnormal echocardiography. CONCLUSION: Echocardiographic abnormalities...... are very common in outpatients with type 2 diabetes, but neither cardiac symptoms nor clinical characteristics are effective to identify patients with echocardiographic abnormalities....

  16. Cardiac cameras.

    Science.gov (United States)

    Travin, Mark I

    2011-05-01

    Cardiac imaging with radiotracers plays an important role in patient evaluation, and the development of suitable imaging instruments has been crucial. While initially performed with the rectilinear scanner that slowly transmitted, in a row-by-row fashion, cardiac count distributions onto various printing media, the Anger scintillation camera allowed electronic determination of tracer energies and of the distribution of radioactive counts in 2D space. Increased sophistication of cardiac cameras and development of powerful computers to analyze, display, and quantify data has been essential to making radionuclide cardiac imaging a key component of the cardiac work-up. Newer processing algorithms and solid state cameras, fundamentally different from the Anger camera, show promise to provide higher counting efficiency and resolution, leading to better image quality, more patient comfort and potentially lower radiation exposure. While the focus has been on myocardial perfusion imaging with single-photon emission computed tomography, increased use of positron emission tomography is broadening the field to include molecular imaging of the myocardium and of the coronary vasculature. Further advances may require integrating cardiac nuclear cameras with other imaging devices, ie, hybrid imaging cameras. The goal is to image the heart and its physiological processes as accurately as possible, to prevent and cure disease processes.

  17. 早期复极综合征与特发性室颤及猝死%Idiopathic ventricular fibrillation and sudden death associated with early repolarization syndrome.

    Institute of Scientific and Technical Information of China (English)

    陈漠水

    2011-01-01

    Early repolarization syndrome (ERS) is a well-recognized idiopathic electrocardiographic phenomenon characterized by prominent J wave and a positive large T wave and ST-segment elevation, concave to the top, predominantly in left precordial (V3~V6 ) leads. It was generally thought that ERS is benign, but recently a growing number of case reports indicate that in some instances, ERS repeatedly induces idiopathic ventricular fibrillation which causes sudden death, suggesting that ERS is associated with idiopathic ventricular fibrillation and sudden death.However, the mechanism of its arrhythmogenic potential still remains unknown. Therefore, patients with ERS who have chest pain, unexplained syncope or other symptoms and at high risks of family history of sudden death should be automatically transferred implantable cardiac defibrillator (ICD) to improve the prognosis. This review summarizes the current state of knowledge concerning ERS associated with idiopathic ventricular fibrillation and sudden death.%早期复极综合征(ERS)是一种以心电图上表现为J波增大或J点抬高,胸前导联V3-V6弓背向下的ST段抬高和高大而直立的T波的特征性的心电改变,通常认为是一种正常心电图的良性变异,但近来报道早期复极综合征在一些情况下可诱发特发性心室颤动,导致猝死,机制尚未明确.对于有胸痛、晕厥等症状或(和)猝死家族史等的高危ERS患者,应植入型心脏自动转律除颤器(ICD)以改善预后.

  18. Prevalence of Brugada-type ECG pattern and early ventricular repolarization pattern in Tunisian athletes

    Directory of Open Access Journals (Sweden)

    Ouali S

    2011-04-01

    Full Text Available Sana Ouali1, Helmi Ben Salem1, Sami Hammas1, Elyes Neffeti1, Fahmi Remedi1, Abdallah Mahdhaoui2, Essia Boughzela1, Rafik Mankai31Department of Cardiology, Sahloul Hospital, Sousse, Tunisia; 2Department of Cardiology, Farhat Hached, Sousse, Tunisia; 3Central Sports Medicine Centre of El Menzah, TunisiaIntroduction: No data regarding the prevalence of the Brugada-type electrocardiogram (ECG pattern and the early ventricular repolarization pattern (ERP in the North African population were available. The aims of this study were to determine the frequency of Brugada-type ECG pattern and ERP in Tunisia and to evaluate ECG descriptors of ventricular repolarization in a population of athletes.Methods: Over a 2-year period, resting 12-lead ECG recordings were analyzed from athletes (n = 540; 348 males; age 18.3 ± 2.4 years. Brugada-type ECG pattern was defined as Type 1, 2, or 3, and ERP was characterized by an elevation of the J point in the inferior and/or lateral leads. The population was divided into three groups of athletes: ERP group; Brugada-type ECG pattern group; and control group, with neither ERP nor Brugada ECG pattern. Clinical and electrocardiographic parameters were compared among the study groups.Results: Nine subjects (1.66% had a Brugada-type ECG pattern. None of them had the coved-type, 3 (0.6% had the Type 2, and 6 (1.1% had the Type 3. All subjects were asymptomatic. A Brugada-type ECG pattern was observed in seven males. No female had the Type 2 Brugada ECG pattern. ECG parameters were similar among Brugada-type ECG pattern and control athletes. ERP (119 subjects, 22% was obtained in 98 males. Heart rate was lower, the QRS duration shorter and QT and Tpeak–Tend intervals were longer in ERP than control groups.Conclusion: The results indicate that the frequency of the Brugada-type ECG pattern and ERP were respectively 1.66% and 22.00% in athletes, being more prevalent in males. The ERP group experienced shorter QRS duration and

  19. Two components of delayed rectifier K+ current in heart:molecular basis,functional diversity,and contribution to repolarization

    Institute of Scientific and Technical Information of China (English)

    Jian-hua CHENG; Itsuo KODAMA

    2004-01-01

    Delayed rectifier K+ current (IK) is the major outward current responsible for ventricular repolarization. Two components of IK (IKr and IKs) have been identified in many mammalian species including humans. IKr. plays a pivotal role in normal ventricular repolarization. A prolongation of action potential duration (APD) under a variety of conditions would favor the activation of IKs so that to prevent excessive repolarization delay causing early afterdepolarization. The pore-forming α subunits of IKr and IKs are composed of HERG (KCNH2) and KvLQT l (KCNQ l), respectively. KvLQT l is associated with a function-altering β subunit, minK to form IKs. HERG may be associated with minK (KCNE1) and/or minK-related protein (MiRP1) to form IKr, but the issue remains to be established. IKs is enhanced, whereas IKr is usually attenuated by β-adrenergic stimulation via cyclic adenosine 31,51-monophosphate (cAMP)/protein kinase A-dependent pathways. There exist regional differences in the density of IKr and IKs transmurally (endo-epicardial) and along the apico-basal axis, contributing to the spatial heterogeneity of ventricular repolarization. A decrease of IKr or IKs by mutations in either HERG, KvLQTl, or KCNE family results in inherited long QT syndrome (LQTS) with high risk for Torsades de pointes (TdP)-type polymorphic ventricular tachycardia and ventricular fibrillation. As to the pharmacological treatment and prevention of ventricular tachyarrhythmias, selectively block of IKs is expected to be more beneficial than selectively block of IKr in terms of homogeneous prolongation of refractoriness at high heart rates especially in diseased hearts including myocardial ischemia.

  20. Lack of significant effect of bilastine administered at therapeutic and supratherapeutic doses and concomitantly with ketoconazole on ventricular repolarization: results of a thorough QT study (TQTS) with QT-concentration analysis.

    Science.gov (United States)

    Tyl, Benoît; Kabbaj, Meriam; Azzam, Sara; Sologuren, Ander; Valiente, Román; Reinbolt, Elizabeth; Roupe, Kathryn; Blanco, Nathalie; Wheeler, William

    2012-06-01

    The effect of bilastine on cardiac repolarization was studied in 30 healthy participants during a multiple-dose, triple-dummy, crossover, thorough QT study that included 5 arms: placebo, active control (400 mg moxifloxacin), bilastine at therapeutic and supratherapeutic doses (20 mg and 100 mg once daily, respectively), and bilastine 20 mg administered with ketoconazole 400 mg. Time-matched, triplicate electrocardiograms (ECGs) were recorded with 13 time points extracted predose and 16 extracted over 72 hours post day 4 dosing. Four QT/RR corrections were implemented: QTcB; QTcF; a linear individual correction (QTcNi), the primary correction; and a nonlinear one (QTcNnl). Moxifloxacin was associated with a significant increase in QTcNi at all time points between 1 and 12 hours, inclusively. Bilastine administration at 20 mg and 100 mg had no clinically significant impact on QTc (maximum increase in QTcNi, 5.02 ms; upper confidence limit [UCL] of the 1-sided, 95% confidence interval, 7.87 ms). Concomitant administration of ketoconazole and bilastine 20 mg induced a clinically relevant increase in QTc (maximum increase in QTcNi, 9.3 ms; UCL, 12.16 ms). This result was most likely related to the cardiac effect of ketoconazole because for all time points, bilastine plasma concentrations were lower than those observed following the supratherapeutic dose.

  1. Cardiac hybrid imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gaemperli, Oliver [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); University Hospital Zurich, Nuclear Cardiology, Cardiovascular Center, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland)

    2014-05-15

    Hybrid cardiac single photon emission computed tomography (SPECT)/CT imaging allows combined assessment of anatomical and functional aspects of cardiac disease. In coronary artery disease (CAD), hybrid SPECT/CT imaging allows detection of coronary artery stenosis and myocardial perfusion abnormalities. The clinical value of hybrid imaging has been documented in several subsets of patients. In selected groups of patients, hybrid imaging improves the diagnostic accuracy to detect CAD compared to the single imaging techniques. Additionally, this approach facilitates functional interrogation of coronary stenoses and guidance with regard to revascularization procedures. Moreover, the anatomical information obtained from CT coronary angiography or coronary artery calcium scores (CACS) adds prognostic information over perfusion data from SPECT. The use of cardiac hybrid imaging has been favoured by the dissemination of dedicated hybrid systems and the release of dedicated image fusion software, which allow simple patient throughput for hybrid SPECT/CT studies. Further technological improvements such as more efficient detector technology to allow for low-radiation protocols, ultra-fast image acquisition and improved low-noise image reconstruction algorithms will be instrumental to further promote hybrid SPECT/CT in research and clinical practice. (orig.)

  2. Haemodynamic findings on cardiac CT in children with congenital heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Hyun Woo [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, Seoul (Korea, Republic of)

    2011-02-15

    In patients with congenital heart disease, haemodynamic findings demonstrated on cardiac CT might provide useful hints for understanding the haemodynamics of cardiac defects. In contrast to morphological features depicted on cardiac CT, such haemodynamic findings on cardiac CT have not been comprehensively reviewed in patients with congenital heart disease. This article describes normal haemodynamic phenomena of cardiovascular structures and various abnormal haemodynamic findings with their mechanisms and clinical significance on cardiac CT in patients with congenital heart disease. (orig.)

  3. Urine - abnormal color

    Science.gov (United States)

    ... medlineplus.gov/ency/article/003139.htm Urine - abnormal color To use the sharing features on this page, please enable JavaScript. The usual color of urine is straw-yellow. Abnormally colored urine ...

  4. Cardiac CT Angiography in Congestive Heart Failure.

    Science.gov (United States)

    Levine, Avi; Hecht, Harvey S

    2015-06-01

    Cardiac CT angiography has become an important tool for the diagnosis and treatment of congestive heart failure. Differentiation of ischemic from nonischemic cardiomyopathy; evaluation of myocardial perfusion; characterization of hypertrophic cardiomyopathy, left ventricular noncompaction, and arrhythmogenic right ventricular dysplasia; and delineation of congenital heart defects and valvular abnormalities are the primary diagnostic applications. Therapeutic use includes visualization of the coronary venous anatomy for optimal implementation of cardiac resynchronization therapy and evaluation of left ventricular assist devices and transplant vasculopathy.

  5. Cardiac ion channels in health and disease.

    Science.gov (United States)

    Amin, Ahmad S; Tan, Hanno L; Wilde, Arthur A M

    2010-01-01

    Cardiac electrical activity depends on the coordinated propagation of excitatory stimuli through the heart and, as a consequence, the generation of action potentials in individual cardiomyocytes. Action potential formation results from the opening and closing (gating) of ion channels that are expressed within the sarcolemma of cardiomyocytes. Ion channels possess distinct genetic, molecular, pharmacologic, and gating properties and exhibit dissimilar expression levels within different cardiac regions. By gating, ion channels permit ion currents across the sarcolemma, thereby creating the different phases of the action potential (e.g., resting phase, depolarization, repolarization). The importance of ion channels in maintaining normal heart rhythm is reflected by the increased incidence of arrhythmias in inherited diseases that are linked to mutations in genes encoding ion channels or their accessory proteins and in acquired diseases that are associated with changes in ion channel expression levels or gating properties. This review discusses ion channels that contribute to action potential formation in healthy hearts and their role in inherited and acquired diseases.

  6. Cardiac echinococcosis

    Directory of Open Access Journals (Sweden)

    Ivanović-Krstić Branislava A.

    2002-01-01

    Full Text Available Cardiac hydatid disease is rare. We report on an uncommon hydatid cyst localized in the right ventricular wall, right atrial wall tricuspid valve left atrium and pericard. A 33-year-old woman was treated for cough, fever and chest pain. Cardiac echocardiograpic examination revealed a round tumor (5.8 x 4 cm in the right ventricular free wall and two smaller cysts behind that tumor. There were cysts in right atrial wall and tricuspidal valve as well. Serologic tests for hydatidosis were positive. Computed tomography finding was consistent with diagnosis of hydatid cyst in lungs and right hylar part. Surgical treatment was rejected due to great risk of cardiac perforation. Medical treatment with albendazole was unsuccessful and the patient died due to systemic hydatid involvement of the lungs, liver and central nervous system.

  7. Cardiac diastolic dysfunction in high-fat diet fed mice is associated with lipotoxicity without impairment of cardiac energetics in vivo

    NARCIS (Netherlands)

    Abdurrachim, Desiree; Ciapaite, Jolita; Wessels, Bart; Nabben, Miranda; Luiken, Joost J. F. P.; Nicolay, Klaas; Prompers, Jeanine J.

    2014-01-01

    Obesity is often associated with abnormalities in cardiac morphology and function. This study tested the hypothesis that obesity-related cardiomyopathy is caused by impaired cardiac energetics. In a mouse model of high-fat diet (HFD)-induced obesity, we applied in vivo cardiac P-31 magnetic resonanc

  8. Common cardiac arrhythmias: recognition and treatment.

    Science.gov (United States)

    Talmers, F N; Kinhal, V; Sabharwal, S; Weissler, A M

    1981-04-01

    Cardiac arrhythmias are commonly seen in the everyday practice of medicine by the physician. Although certain arrhythmias may be suspected clinically, precise diagnosis is made by electrocardiographic recording of the abnormal rhythm. Once the arrhythmia has been recorded, the next steps are proper electrocardiographic diagnosis and selection of proper treatment. The specific mode of therapy and the speed with which it is delivered will depend not only on the type of arrhythmia, but also on the hemodynamic consequences of the rhythm abnormality on the patient's cardiovascular system. The purpose of this paper is to discuss the electrocardiographic criteria of common cardiac arrhythmias as well as current concepts regarding therapy.

  9. A fatal combination in an old lady: Tako-Tsubo cardiomyopathy, long QT syndrome, and cardiac hypertrophy.

    Science.gov (United States)

    Wedekind, Horst; Müller, Joachim G; Ribbing, Michael; Skurzewski, Paul; Bozzetti, Christoph; Meyer-Krahmer, Hans-Joachim; Böcker, Dirk

    2009-06-01

    Tako-Tsubo cardiomyopathy (TT-CM), also called stress-induced cardiomyopathy or transient left ventricular (LV) apical ballooning syndrome, is characterized by transient apical or midventricular LV dysfunction that mimics myocardial infarction, but in the absence of significant coronary artery disease. The onset of TT-CM is typically triggered by an acute medical illness or by intense emotional, psychological, or physical stress. During the acute phase, a disturbed repolarization with QT prolongation in the surface ECG is frequently obvious. Despite the generally good prognosis of TT-CM, severe clinical courses have been reported due to the depressed LV function with cardiogenic shock or malignant tachyarrhythmias. We report an unusual presentation of a patient with TT-CM and recurrent episodes of torsades de pointes tachyarrhythmias. In this patient, we identified pre- and coexisting congenital long QT syndrome and severe cardiac hypertrophy--all of them associated with disturbed myocardial repolarization and predisposed the patient to malignant tachyarrhythmias.

  10. Beta-adrenergic stimulation reverses the IKr–IKs dominant pattern during cardiac action potential

    Science.gov (United States)

    Banyasz, Tamas; Jian, Zhong; Horvath, Balazs; Khabbaz, Shaden; Izu, Leighton T.; Chen-Izu, Ye

    2014-01-01

    β-adrenergic stimulation differentially modulates different K+ channels and thus fine-tunes cardiac action potential (AP) repolarization. However, it remains unclear how the proportion of IKs, IKr, and IK1 current in the same cell would be altered by β-adrenergic stimulation, which would change the relative contribution of individual K+ current to the total repolarization reserve. In this study we used an innovative AP-clamp Sequential Dissection technique to directly record the dynamic –IKs, IKr, IK1– currents during the AP in guinea pig ventricular myocytes under physiologically relevant conditions. Our data provide quantitative measures of the magnitude and time course of IKs, IKr, IK1 currents in the same cell under its own steady-state AP, in a physiological milieu, and with preserved Ca2+ homeostasis. We found that isoproterenol treatment significantly enhanced IKs, moderately increased IK1, but slightly decreased IKr in a dose-dependent manner. The dominance pattern of the K+ currents was IKr>IK1>IKs at the control condition, but reversed to IKrcardiac repolarization during AP at different adrenergic states. In conclusion, the β-adrenergic stimulation fine-tunes the cardiac AP morphology by shifting the power of different K+ currents in a dose-dependent manner. This Knowledge is important for designing anti-arrhythmic drug strategies to treat the hearts exposed to various sympathetic tones. PMID:24535581

  11. Cardiac Rehabilitation

    Science.gov (United States)

    ... your risk of future heart problems, and to improve your health and quality of life. Cardiac rehabilitation programs increase ... exercise routine at home or at a local gym. You may also continue to ... health concerns. Education about nutrition, lifestyle and weight loss ...

  12. Reduction in dynamin-2 is implicated in ischaemic cardiac arrhythmias.

    Science.gov (United States)

    Shi, Dan; Xie, Duanyang; Zhang, Hong; Zhao, Hong; Huang, Jian; Li, Changming; Liu, Yi; Lv, Fei; The, Erlinda; Liu, Yuan; Yuan, Tianyou; Wang, Shiyi; Chen, Jinjin; Pan, Lei; Yu, Zuoren; Liang, Dandan; Zhu, Weidong; Zhang, Yuzhen; Li, Li; Peng, Luying; Li, Jun; Chen, Yi-Han

    2014-10-01

    Ischaemic cardiac arrhythmias cause a large proportion of sudden cardiac deaths worldwide. The ischaemic arrhythmogenesis is primarily because of the dysfunction and adverse remodelling of sarcolemma ion channels. However, the potential regulators of sarcolemma ion channel turnover and function in ischaemic cardiac arrhythmias remains unknown. Our previous studies indicate that dynamin-2 (DNM2), a cardiac membrane-remodelling GTPase, modulates ion channels membrane trafficking in the cardiomyocytes. Here, we have found that DNM2 plays an important role in acute ischaemic arrhythmias. In rat ventricular tissues and primary cardiomyocytes subjected to acute ischaemic stress, the DNM2 protein and transcription levels were markedly down-regulated. This DNM2 reduction was coupled with severe ventricular arrhythmias. Moreover, we identified that the down-regulation of DNM2 within cardiomyocytes increases the action potential amplitude and prolongs the re-polarization duration by depressing the retrograde trafficking of Nav1.5 and Kir2.1 channels. These effects are likely to account for the DNM2 defect-induced arrhythmogenic potentials. These results suggest that DNM2, with its multi-ion channel targeting properties, could be a promising target for novel antiarrhythmic therapies.

  13. Flecainide attenuates rate adaptation of ventricular repolarization in guinea-pig heart

    DEFF Research Database (Denmark)

    Osadchii, Oleg E.

    2016-01-01

    examined flecainide effect on adaptation of the QT interval and ventricular action potential duration (APD) to abrupt reductions of the cardiac cycle length. DESIGN: ECG and ventricular epicardial and endocardial monophasic APD were recorded in isolated, perfused guinea-pig heart preparations upon...... a sustained cardiac acceleration (rapid pacing for 30 s), and following a single perturbation of the cycle length evoked by extrasystolic stimulation. RESULTS: Sustained increase in heart rate was associated with progressive bi-exponential shortening of the QT interval and APD. Flecainide prolonged...

  14. Heterotaxy syndromes and abnormal bowel rotation

    Energy Technology Data Exchange (ETDEWEB)

    Newman, Beverley [Stanford University, Lucile Packard Children' s Hospital, Department of Radiology, Stanford, CA (United States); Koppolu, Raji; Sylvester, Karl [Lucile Packard Children' s Hospital at Stanford, Department of Surgery, Stanford, CA (United States); Murphy, Daniel [Lucile Packard Children' s Hospital at Stanford, Department of Cardiology, Stanford, CA (United States)

    2014-05-15

    Bowel rotation abnormalities in heterotaxy are common. As more children survive cardiac surgery, the management of gastrointestinal abnormalities has become controversial. To evaluate imaging of malrotation in heterotaxy with surgical correlation and provide an algorithm for management. Imaging reports of heterotaxic children with upper gastrointestinal (UGI) and/or small bowel follow-through (SBFT) were reviewed. Subsequently, fluoroscopic images were re-reviewed in conjunction with CT/MR studies. The original reports and re-reviewed images were compared and correlated with surgical findings. Nineteen of 34 children with heterotaxy underwent UGI, 13/19 also had SBFT. In 15/19 reports, bowel rotation was called abnormal: 11 malrotation, 4 non-rotation, no cases of volvulus. Re-review, including CT (10/19) and MR (2/19), designated 17/19 (90%) as abnormal, 10 malrotation (abnormal bowel arrangement, narrow or uncertain length of mesentery) and 7 non-rotation (small bowel and colon on opposite sides plus low cecum with probable broad mesentery). The most useful CT/MR findings were absence of retroperitoneal duodenum in most abnormal cases and location of bowel, especially cecum. Abnormal orientation of mesenteric vessels suggested malrotation but was not universal. Nine children had elective bowel surgery; non-rotation was found in 4/9 and malrotation was found in 5/9, with discrepancies (non-rotation at surgery, malrotation on imaging) with 4 original interpretations and 1 re-review. We recommend routine, early UGI and SBFT studies once other, urgent clinical concerns have been stabilized, with elective laparoscopic surgery in abnormal or equivocal cases. Cross-sectional imaging, usually obtained for other reasons, can contribute diagnostically. Attempting to assess mesenteric width is important in differentiating non-rotation from malrotation and more accurately identifies appropriate surgical candidates. (orig.)

  15. An activation-repolarization time metric to predict localized regions of high susceptibility to re-entry

    Science.gov (United States)

    Child, Nicholas; Bishop, Martin J.; Hanson, Ben; Coronel, Ruben; Opthof, Tobias; Bourkens, Bastiaan; Walton, Richard; Efimov, Igor; Bostock, Julian; Hill, Yolanda; Rinaldi, Christopher A; Razavi, Reza; Gill, Jaswinder; Taggart, Peter

    2015-01-01

    Background Initiation of re-entrant ventricular tachycardia (VT) involves complex interactions between activation and repolarization wavefronts. Recent experimental work has identified the time interval between S2 repolarization proximal to a line of functional block and the activation at the adjacent distal side, as a critical determinant of re-entry. Objective We hypothesized: (1) an algorithm could be developed which would generate a spatial map of this interval (designated the “re-entry vulnerability index”-RVI); (2) that this would accurately identify a pathway of re-entry as well as rotor formation in animal experiments and in a computational model; and, (3) that it would be possible to generate an RVI map in humans during routine clinical procedures and co-register with anatomical and electrophysiological features. Methods and Results An algorithm was developed which sampled all points on a multielectrode grid and calculated RVI between all pairs of electrodes within a given radius. The algorithm successfully identified the spatial region with increased susceptibility to re-entry in an established Langendorff pig heart model and the site of re-entry and rotor formation in an optically mapped sheep heart model and corresponding computational simulations. The feasibility of RVI mapping was evaluated during a clinical procedure by co-registering with the anatomy and physiology in a patient undergoing a VT ablation. Conclusions We developed an algorithm to calculate a re-entry vulnerability index from intervals between local repolarization and activation times at all adjacent points over a multielectrode grid. The algorithm accurately identified the region of re-entry in two animal models of functional re-entry. The possibility of clinical application was demonstrated in a patient with VT. PMID:25863160

  16. A major role for calcium-dependent potassium current in action potential repolarization in adrenal chromaffin cells.

    Science.gov (United States)

    Pancrazio, J J; Johnson, P A; Lynch, C

    1994-12-30

    To determine the extent which Ca dependent K current (IKCa) contributes during an action potential (AP), bovine chromaffin cells were voltage-clamped using a pre-recorded AP as the command voltage waveform. Based on (1) differential sensitivity of IKCa and Ca-independent K current (IK) to tetraethylammonium; (2) measurements of AP currents under conditions where Ca activation of IKCa had been abolished; and (3) blockade by charybdotoxin, IKCa comprised 70-90% of the outward K current during AP repolarization. In addition, observations are made concerning the form of AP-evoked Ca current.

  17. Cardiac Calcification

    Directory of Open Access Journals (Sweden)

    Morteza Joorabian

    2011-05-01

    Full Text Available There is a spectrum of different types of cardiac"ncalcifications with the importance and significance"nof each type of cardiac calcification, especially"ncoronary artery calcification. Radiologic detection of"ncalcifications within the heart is quite common. The"namount of coronary artery calcification correlates"nwith the severity of coronary artery disease (CAD."nCalcification of the aortic or mitral valve may indicate"nhemodynamically significant valvular stenosis."nMyocardial calcification is a sign of prior infarction,"nwhile pericardial calcification is strongly associated"nwith constrictive pericarditis. A spectrum of different"ntypes of cardiac calcifications (linear, annular,"ncurvilinear,... could be seen in chest radiography and"nother imaging modalities. So a carful inspection for"ndetection and reorganization of these calcifications"nshould be necessary. Numerous modalities exist for"nidentifying coronary calcification, including plain"nradiography, fluoroscopy, intravascular ultrasound,"nMRI, echocardiography, and conventional, helical and"nelectron-beam CT (EBCT. Coronary calcifications"ndetected on EBCT or helical CT can be quantifie,"nand a total calcification score (Cardiac Calcification"nScoring may be calculated. In an asymptomatic"npopulation and/or patients with concomitant risk"nfactors like diabetes mellitus, determination of the"npresence of coronary calcifications identifies the"npatients at risk for future myocardial infarction and"ncoronary artery disease. In patients without coronary"ncalcifications, future cardiovascular events could"nbe excluded. Therefore, detecting and recognizing"ncalcification related to the heart on chest radiography"nand other imaging modalities such as fluoroscopy, CT"nand echocardiography may have important clinical"nimplications.

  18. The use of variability of repolarization for monitoring of arrhythmic risk : "the rocking of the boat"

    NARCIS (Netherlands)

    Oosterhoff, P.

    2011-01-01

    The majority of deaths in the western world are of cardiovascular origin. Approximately 60% of these cardiovascular deaths are sudden. Implantation of an implantable cardioverter defibrillator (ICD) has been proven effective in preventing sudden cardiac death in patients at increased risk. An ICD ca

  19. Early repolarization in mice causes overestimation of ventricular activation time by the QRS duration

    NARCIS (Netherlands)

    Boukens, B.J.; Hoogendijk, M.G.; Verkerk, A.O.; Linnenbank, A.; Dam, P.M. van; Remme, C.A.; Fiolet, J.W.; Opthof, T.; Christoffels, V.M.; Coronel, R.

    2013-01-01

    AIMS: Transgenic mice are frequently used to investigate the role of genes involved in cardiac conduction. The QRS duration calculated from the electrocardiogram (ECG) is a commonly used measure for ventricular conduction time. However, the relation between ventricular activation and QRS duration ca

  20. Potassium currents in the heart: functional roles in repolarization, arrhythmia and therapeutics.

    Science.gov (United States)

    Chiamvimonvat, Nipavan; Chen-Izu, Ye; Clancy, Colleen E; Deschenes, Isabelle; Dobrev, Dobromir; Heijman, Jordi; Izu, Leighton; Qu, Zhilin; Ripplinger, Crystal M; Vandenberg, Jamie I; Weiss, James N; Koren, Gideon; Banyasz, Tamas; Grandi, Eleonora; Sanguinetti, Michael C; Bers, Donald M; Nerbonne, Jeanne M

    2016-11-03

    This is the second of the two White Papers from the fourth UC Davis Cardiovascular Symposium Systems Approach to Understanding Cardiac Excitation-Contraction Coupling and Arrhythmias (3-4 March 2016), a biennial event that brings together leading experts in different fields of cardiovascular research. The theme of the 2016 symposium was 'K(+) channels and regulation', and the objectives of the conference were severalfold: (1) to identify current knowledge gaps; (2) to understand what may go wrong in the diseased heart and why; (3) to identify possible novel therapeutic targets; and (4) to further the development of systems biology approaches to decipher the molecular mechanisms and treatment of cardiac arrhythmias. The sessions of the Symposium focusing on the functional roles of the cardiac K(+) channel in health and disease, as well as K(+) channels as therapeutic targets, were contributed by Ye Chen-Izu, Gideon Koren, James Weiss, David Paterson, David Christini, Dobromir Dobrev, Jordi Heijman, Thomas O'Hara, Crystal Ripplinger, Zhilin Qu, Jamie Vandenberg, Colleen Clancy, Isabelle Deschenes, Leighton Izu, Tamas Banyasz, Andras Varro, Heike Wulff, Eleonora Grandi, Michael Sanguinetti, Donald Bers, Jeanne Nerbonne and Nipavan Chiamvimonvat as speakers and panel discussants. This article summarizes state-of-the-art knowledge and controversies on the functional roles of cardiac K(+) channels in normal and diseased heart. We endeavour to integrate current knowledge at multiple scales, from the single cell to the whole organ levels, and from both experimental and computational studies.

  1. Cardiac function in trisomy 21 fetuses

    NARCIS (Netherlands)

    Clur, S. A. B.; Rengerink, K. Oude; Ottenkamp, J.; Bilardo, C. M.

    2011-01-01

    Objectives Trisomy 21 is associated with an increased nuchal translucency thickness (NT), abnormal ductus venosus (DV) flow at 11-14 weeks' gestation and congenital heart defects (CHD), and cardiac dysfunction has been hypothesized as the link between them. We therefore aimed to investigate whether

  2. Hereditary urea cycle abnormality

    Science.gov (United States)

    ... vitro so the specific genetic cause is known. Teamwork between parents, the affected child, and doctors can help prevent severe illness. Alternative Names Abnormality of the urea cycle - hereditary; Urea cycle - hereditary abnormality Images Male urinary system Urea cycle References Lichter-Konecki ...

  3. Cardiac electromechanics and the forward/inverse problems of electrocardiology.

    Science.gov (United States)

    Buist, M; Smith, N P; Pullan, A J

    2005-01-01

    The mechanical motion of the heart plays a role in determining the waveforms observed in an ECG. This study is designed to ascertain, from a theoretical perspective, the influence of this motion. This is achieved through an analysis of a detailed forward model including a full bidomain description and a strongly coupled model of cardiac electromechanics. Simulations were run on identical problems with and without the inclusion of mechanical deformation and the results were analyzed with a view towards the inverse problem of electrocardiology. Initial results have shown the QRS complex to be largely invariant under deformation, but significant changes in T wave morphology have been observed. Further analysis has revealed that it is the effect of the cell-level mechanics on repolarization that is primarily responsible for these changes as opposed to the tissue deformation.

  4. Cardiac MRI and CT features of inheritable and congenital conditions associated with sudden cardiac death

    Energy Technology Data Exchange (ETDEWEB)

    Sparrow, Patrick; Merchant, Naeem; Provost, Yves; Doyle, Deirdre; Nguyen, Elsie; Paul, Narinder [University Health Network and Mount Sinai Hospital, Division of Cardiothoracic Imaging, Department of Medical Imaging, Toronto, Ontario (Canada)

    2009-02-15

    Cardiac MRI (CMR) and electrocardiogram (ECG)-gated multi-detector computed tomography (MDCT) are increasingly important tools in the identification and assessment of cardiac-related disease processes, including those associated with sudden cardiac death (SCD). While the commonest cause of SCD is coronary artery disease (CAD), in patients under 35 years inheritable cardiomyopathies such as hypertrophic cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy are important aetiologies. CMR in particular offers both accurate delineation of the morphological abnormalities associated with these and other conditions and the possibility for risk stratification for development of ventricular arrhythmias with demonstration of macroscopic scar by delayed enhancement imaging with intravenous gadolinium. (orig.)

  5. THE EFFICACY OF MELDONIUM IN REDUCTION OF CARDIAC ELECTRICAL INSTABILITY IN PATIENTS WITH ISCHEMIC STROKE

    Directory of Open Access Journals (Sweden)

    A. A. Abdullaev

    2015-09-01

    Full Text Available Aim. To study meldonium effect in the combination therapy for ventricular repolarization disorders and cardiac electrical instability in patients with ischemic stroke.Material and methods. Patients (n=46 with acute phase of ischemic stroke were included in a randomized, open-label, uncontrolled study. Patients were randomized into two groups. Group 1 patients (n=25 had been receiving meldonium (Mildronate;Grindex,Latvia;Pharmstandard,Russia, 1.0 g/day intravenously once daily, as a part of standard therapy for 10 days since admission to the hospital. Group 2 patients (n=21 had standard therapy alone. A standart 12-lead ECG, ventricular late potentials (VLP, 24-hour Holter monitoring, troponin test were performed at the baseline and after 10 days.Results. Patients of the group 1 as compared to the group 2 demonstrated more significant positive effect on the clinical condition of patients with ischemic stroke, ventricular repolarization, reduction of frequency (from 3.7±0.5 to 2.1±0.4; p<0.05 and duration (from 6.6±1, 3 to 4.0±1.1 min; p<0.05 of painless myocardial ischemia episodes and VLP (from 48 to 32%.Conclusion. Adding meldonium to standard therapy in patients with acute phase of ischemic stroke can have a positive effect on the clinical condition, repolarization disorders on ECG, frequency of VLP and episodes of painless myocardial ischemia detection. This may have a positive effect on the electrical stability and prevention of cardiac arrhythmias. 

  6. THE EFFICACY OF MELDONIUM IN REDUCTION OF CARDIAC ELECTRICAL INSTABILITY IN PATIENTS WITH ISCHEMIC STROKE

    Directory of Open Access Journals (Sweden)

    A. A. Abdullaev

    2014-01-01

    Full Text Available Aim. To study meldonium effect in the combination therapy for ventricular repolarization disorders and cardiac electrical instability in patients with ischemic stroke.Material and methods. Patients (n=46 with acute phase of ischemic stroke were included in a randomized, open-label, uncontrolled study. Patients were randomized into two groups. Group 1 patients (n=25 had been receiving meldonium (Mildronate;Grindex,Latvia;Pharmstandard,Russia, 1.0 g/day intravenously once daily, as a part of standard therapy for 10 days since admission to the hospital. Group 2 patients (n=21 had standard therapy alone. A standart 12-lead ECG, ventricular late potentials (VLP, 24-hour Holter monitoring, troponin test were performed at the baseline and after 10 days.Results. Patients of the group 1 as compared to the group 2 demonstrated more significant positive effect on the clinical condition of patients with ischemic stroke, ventricular repolarization, reduction of frequency (from 3.7±0.5 to 2.1±0.4; p<0.05 and duration (from 6.6±1, 3 to 4.0±1.1 min; p<0.05 of painless myocardial ischemia episodes and VLP (from 48 to 32%.Conclusion. Adding meldonium to standard therapy in patients with acute phase of ischemic stroke can have a positive effect on the clinical condition, repolarization disorders on ECG, frequency of VLP and episodes of painless myocardial ischemia detection. This may have a positive effect on the electrical stability and prevention of cardiac arrhythmias. 

  7. Exercise-induced cardiac fatigue in low handicap polo horses

    Directory of Open Access Journals (Sweden)

    CAO Bello

    2014-01-01

    Full Text Available Physical exercise leads to several changes in the cardiovascular system of horses and may induce abnormalities that are not observed at rest. Little is known about the cardiac effects of intense physical exercise performed by horses in polo competitions. This study aimed at identifying if exercise-induced cardiac fatigue is observed in healthy polo ponies. We examined 25 equine athletes before and after a training match. The results demonstrated post-exercise electrocardiographic alteration such as cardiac arrhythmia, QTc prolongation, abnormal T waves and ST-segment elevation. The post-exercise echocardiogram showed interventricular septum and left ventricle free wall thickness reduction, systolic volume decreased and ejection fraction decreased. These results suggest that polo causes exercise-induced cardiac fatigue. It was not possible to establish accurately the etiology of this abnormality, nor its long-term consequences.

  8. Effect of Lidocaine and Amiodarone on Transmural Heterogeneityricular Repolarization in Isolated Rabbit Hearts Model of Sustained Global Ischemia

    Institute of Scientific and Technical Information of China (English)

    YOU Binquan; PU Jun; LIU Nian; YU Ronghui; RUAN Yanfei; LI Yang; WANG Lin

    2005-01-01

    To study the effect of of lidocaine and amiodarone on the transmural heterogeneity of ventricular repolarization in isolated rabbit hearts model of sustained global ischemia and to explore the mechanisms underlying the antiarrhythmic activity of lidocaine and amiodarone, rabbits were randomly divided into 4 groups: control group, ischemia group, lidocaine group and amiodarone group. By the monophasic action potential (MAP) recording technique, MAPs of recorded across the left ventricular free wall in rabbit hearts perfused transmural dispersion of repolarization (TDR) and arrhythmic induced by ischemia. Our results showed that TDR of three myocardial layers in ischemia group were significantly lengthened after ischemia. TDR was increased from 17.5±3.9 ms to 31.2±4.6 ms at the time that concided with the onset of sustained ventricle arrhythmic. Amiodarone could decrease TDR, but lidocaine could increase TDR at initial ischemia, and no significant difference was found at other ischemia time points. 5 cases had ventriclar arrhythmia in ischemia group (62.5 %), but no case in lidocaine group (P<0.01) and only 1 case in amiodarone group had ventrilar arrhythmia (P< 0.01). No significant difference was found between amiodarone group and lidocaine group. It is concluded that TDR of of three myocardial layers increases significantly at ischemia and it is closely associated with development of ventricular arrhythmia, and amiodarone could decrease TDR, but lidocaine could increase TDR at initial ischemia and has no effects at other ischemia time points.

  9. Different mechanisms underlying the repolarization of narrow and wide action potentials in pyramidal cells and interneurons of cat motor cortex.

    Science.gov (United States)

    Chen, W; Zhang, J J; Hu, G Y; Wu, C P

    1996-07-01

    Two different types of action potentials were observed among the pyramidal cells and interneurons in cat motor cortex: the narrow action potentials and the wide action potentials. These two types of action potentials had similar rising phases (528.8 +/- 77.0 vs 553.1 +/- 71.8 mV/ms for the maximal rising rate), but differed in spike duration (0.44 +/- 0.09 vs 1.40 +/- 0.39 ms) and amplitude (57.31 +/- 8.22 vs 72.52 +/- 8.31 mV), implying that the ionic currents contributing to repolarization of these action potentials are different. Here we address this issue by pharmacological manipulation and using voltage-clamp technique in slices of cat motor cortex. Raising extracellular K+ concentration (from 3 mM to 10 mM), applying a low dose of 4-aminopyridine (2-200 microM) or administering a low concentration of tetraethylammonium (0.2-1.0 mM) each not only broadened the narrow action potentials, but also increased their amplitudes. In contrast, high K+ medium or low dose of tetraethylammonium only broadened the wide action potentials, leaving their amplitudes unaffected, and 4-aminopyridine had only a slight broadening effect on the wide spikes. These results implied that K+ currents were involved in the repolarization of both types of action potentials, and that the K+ currents in the narrow action potentials seemed to activate much earlier than those in the wide spikes. This early activated K+ current may counteract the rapid sodium current, yielding the extremely brief duration and small amplitude of the narrow spikes. The sensitivity of the narrow spikes to 4-aminopyridine may not be mainly attributed to blockade of the classical A current (IA), because depolarizing the membrane potential to inactivate IA did not reproduce the effects of 4-aminopyridine. Blockade of Ca2+ influx slowed the last two-thirds repolarization of the wide action potentials. On the contrary, the narrow action potentials were not affected by Ca(2+)-current blockers, but if they were first

  10. Electrocardiography as the First Step for the Further Examination of Cardiac Involvement in Myasthenia Gravis

    Directory of Open Access Journals (Sweden)

    Takao Kato

    2016-01-01

    Full Text Available Introduction. Cardiac involvement of myasthenia gravis (MG accompanies a poor prognosis. In the present study, we aimed to investigate the relationship between ECG abnormality and cardiac involvement. Methods. Of 178 patients diagnosed with MG between 2001 and 2013 at our hospital, we retrospectively analyzed consecutive 58 patients who underwent both ECG and echocardiography and without underlying cardiovascular disease. ECG abnormalities were defined by computer-assigned Minnesota-codes. Cardiac damage was defined as either (1 ejection fraction (EF 8 on echocardiography. Results. Thirty-three patients (56.8% had ECG abnormality. An elevated E/e′ was observed in patients with ECG abnormality compared to those without ECG abnormality (11.2±3.2, 8.7±2.2, resp., p=0.03. Among patients with ECG abnormality, 14 of 15 patients showed cardiac damage. Among patients without ECG abnormality, 6 of 33 patients showed cardiac damage (p=0.003. Reduced EF was observed in five patients (8.6% with ECG abnormality and none in patients without ECG abnormality. Conclusions. ECG may aid as the first step for the further examination of cardiac damage in patients with MG.

  11. Cardiac manifestations of Pallister-Killian syndrome.

    Science.gov (United States)

    Tilton, Richard K; Wilkens, Alisha; Krantz, Ian D; Izumi, Kosuke

    2014-05-01

    Pallister-Killian syndrome (PKS) is a sporadic multisystem genetic diagnosis characterized by facial dysmorphia, variable developmental delay and intellectual impairment, hypotonia, hearing loss, seizures, differences in skin pigmentation, temporal alopecia, diaphragmatic hernia, congenital heart defects, and other systemic abnormalities. Although congenital heart defects have been described in association with PKS, the full spectrum of heart disease is still not entirely known. Here, we describe the pattern of cardiac findings of 81 probands with PKS who have had at least one cardiac evaluation, demonstrating structural heart difference in 37% of our cohort (n = 30). Septal defects such as atrial or ventricular septal defects (n = 12) were the most commonly seen congenital heart differences. Additional findings included the occasional occurrence of bicuspid aortic valve, aortic dilatation, and cardiac hypertrophy/cardiomyopathy. We suggest cardiac evaluation for all individuals with PKS at the time of diagnosis as well as subsequent longitudinal follow-up to monitor for the development of cardiomyopathy and aortic dilatation.

  12. Cardiac sarcoidosis. State of the art

    Directory of Open Access Journals (Sweden)

    Muñoz-Ortiz, Edison

    2016-10-01

    Full Text Available Sarcoidosis is a rare disease of unknown etiology, described over 80 years ago. It is a multisystemic disorder characterized by the presence of granulomatous lesions without caseation. Cardiac involvement varies according to the region, but it is generally accepted that 5 % of patients with systemic sarcoidosis have cardiac infiltration with clinical evidence; however, autopsy studies indicate that up to 20 % to 30 % of patients with sarcoidosis have myocardial involvement. Several factors -environmental, occupational and infectious- have been proposed as triggers of the process in individuals with genetic predisposition. Cardiac sarcoidosis may have a wide range of presentations and may even be asymptomatic; the most common manifestations are heart failure, abnormal heart rhythm and lethal ventricular arrhythmias. Treatment includes medications for heart failure, steroids and immune-suppressants, management of lethal arrhythmias with ablation and/or implantable cardioverter defibrillator and cardiac transplantation in severe cases.

  13. Magnetic resonance imaging of congenital abnormalities of the thoracic aorta

    Energy Technology Data Exchange (ETDEWEB)

    Soler, R.; Rodriguez, E.; Requejo, I.; Fernandez, R. [Department of Radiology, Hospital Juan Canalejo, La Coruma (Spain); Raposo, I. [Department of Pediatric Cardiology, Hospital Juan Canalejo, La Coruna (Spain)

    1998-05-01

    This article outlines the ability of MR imaging in the detection and presurgical evaluation of congenital abnormalities of the thoracic aorta (CATA). Congenital abnormalities of the thoracic aorta may be found incidentally on chest radiographs in patients without symptoms, or it can be associated with clinical findings which are very variable depending on the association with congenital cardiac malformations or vascular ring. When CATA is suspected as the cause of anomalies in the mediastinum in asymptomatic patients, confirmation of the abnormality should be by MR imaging allowing precise evaluation of the thoracic aorta and origin of the principal arteries. When CATA is considered because clinical findings indicate coarctation of the aorta, vascular ring or associated cardiac disorder, evaluation with ultrasound can be complemented by MR, which in most cases will replace the diagnostic catheterization. (orig.) With 12 figs., 24 refs.

  14. Beta-adrenergic stimulation reverses the I Kr-I Ks dominant pattern during cardiac action potential.

    Science.gov (United States)

    Banyasz, Tamas; Jian, Zhong; Horvath, Balazs; Khabbaz, Shaden; Izu, Leighton T; Chen-Izu, Ye

    2014-11-01

    β-Adrenergic stimulation differentially modulates different K(+) channels and thus fine-tunes cardiac action potential (AP) repolarization. However, it remains unclear how the proportion of I Ks, I Kr, and I K1 currents in the same cell would be altered by β-adrenergic stimulation, which would change the relative contribution of individual K(+) current to the total repolarization reserve. In this study, we used an innovative AP-clamp sequential dissection technique to directly record the dynamic I Ks, I Kr, and I K1 currents during the AP in guinea pig ventricular myocytes under physiologically relevant conditions. Our data provide quantitative measures of the magnitude and time course of I Ks, I Kr, and I K1 currents in the same cell under its own steady-state AP, in a physiological milieu, and with preserved Ca(2+) homeostasis. We found that isoproterenol treatment significantly enhanced I Ks, moderately increased I K1, but slightly decreased I Kr in a dose-dependent manner. The dominance pattern of the K(+) currents was I Kr > I K1 > I Ks at the control condition, but reversed to I Kr < I K1 < I Ks following β-adrenergic stimulation. We systematically determined the changes in the relative contribution of I Ks, I Kr, and I K1 to cardiac repolarization during AP at different adrenergic states. In conclusion, the β-adrenergic stimulation fine-tunes the cardiac AP morphology by shifting the power of different K(+) currents in a dose-dependent manner. This knowledge is important for designing antiarrhythmic drug strategies to treat hearts exposed to various sympathetic tones.

  15. "Jeopardy" in Abnormal Psychology.

    Science.gov (United States)

    Keutzer, Carolin S.

    1993-01-01

    Describes the use of the board game, Jeopardy, in a college level abnormal psychology course. Finds increased student interaction and improved application of information. Reports generally favorable student evaluation of the technique. (CFR)

  16. Chromosomal Abnormalities in ADHD

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2002-07-01

    Full Text Available The prevalence of fragile X syndrome, velocardiofacial syndrome (VCFS, and other cytogenetic abnormalities among 100 children (64 boys with combined type ADHD and normal intelligence was assessed at the NIMH and Georgetown University Medical Center.

  17. Abnormal menstrual periods (image)

    Science.gov (United States)

    ... may have a variety of causes, such as endometrial hyperplasia, endometrial polyps, uterine fibroids, and abnormal thyroid or ... the endometrium becomes unusually thick it is called endometrial ... Hyperplasia may cause profuse or extended menstrual bleeding.

  18. Chromosomal abnormalities and autism

    Directory of Open Access Journals (Sweden)

    Farida El-Baz

    2016-01-01

    Conclusion: Chromosomal abnormalities were not detected in the studied autistic children, and so the relation between the genetics and autism still needs further work up with different study methods and techniques.

  19. Approximate analytical solutions for excitation and propagation in cardiac tissue

    Science.gov (United States)

    Greene, D'Artagnan; Shiferaw, Yohannes

    2015-04-01

    It is well known that a variety of cardiac arrhythmias are initiated by a focal excitation in heart tissue. At the single cell level these currents are typically induced by intracellular processes such as spontaneous calcium release (SCR). However, it is not understood how the size and morphology of these focal excitations are related to the electrophysiological properties of cardiac cells. In this paper a detailed physiologically based ionic model is analyzed by projecting the excitation dynamics to a reduced one-dimensional parameter space. Based on this analysis we show that the inward current required for an excitation to occur is largely dictated by the voltage dependence of the inward rectifier potassium current (IK 1) , and is insensitive to the detailed properties of the sodium current. We derive an analytical expression relating the size of a stimulus and the critical current required to induce a propagating action potential (AP), and argue that this relationship determines the necessary number of cells that must undergo SCR in order to induce ectopic activity in cardiac tissue. Finally, we show that, once a focal excitation begins to propagate, its propagation characteristics, such as the conduction velocity and the critical radius for propagation, are largely determined by the sodium and gap junction currents with a substantially lesser effect due to repolarizing potassium currents. These results reveal the relationship between ion channel properties and important tissue scale processes such as excitation and propagation.

  20. Abnormal protein aggregationand neurodegenerativediseases

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Abnormal protein aggregation or amyloid is the major cause ofmany neurodegenerative disorders. The present review focuses on the correlation between sequence and structure features of proteins related to the diseases and abnormal protein aggregation. Recent progress has improved our knowledge on understand-ing the mechanism of amyloid formation. We suggest a nucleation model for ordered protein aggregation, which can also explain pathogenesis mechanisms of these neurodegenerative diseases in vivo.

  1. [Cardiac toxicity of 5-fluorouracil].

    Science.gov (United States)

    Fournier, C; Benahmed, M; Blondeau, M

    1989-02-01

    A 67 year-old patient receives 5-fluorouracil for vocal chord cancer. During the perfusion, atypical angina pain occurs, accompanied with offset of ST above the baseline in standard leads and in V4 through V6. The pain subsides spontaneously in 45 minutes. These ECG alterations are followed 48 hours later by diffuse inverted T waves with lengthened QT. Cardiac ultrasonography and isotopic angiography do not show any abnormality of the left ventricular function, but myocardial tomoscintigraphy with labelled thallium show a lower hypofixation on exertion. The cardiac toxicity of 5-fluorouracil is in frequent. It is usually believed that it involves a coronary spasm, as suggested by the ECG tracing in the reported cases. The incident, which may be painful or painless, may result in a myocardial infarction or even sudden death during the perfusion. Therefore, it is advisable to discontinue the treatment as soon as an angina-type pain occurs.

  2. Cardiac abnormalities in youth with obesity and type 2 diabetes

    Science.gov (United States)

    Childhood obesity has been linked to cardiovascular disease (CVD) risk in adulthood. Of great concern is the expected increase in the population's CVD burden in relation to childhood obesity. This is compounded by the risk related to chronic hyperglycemia exposure in youth with type 2 diabetes. We h...

  3. Abnormalities of the QT interval in primary disorders of autonomic failure

    Science.gov (United States)

    Choy, A. M.; Lang, C. C.; Roden, D. M.; Robertson, D.; Wood, A. J.; Robertson, R. M.; Biaggioni, I.

    1998-01-01

    BACKGROUND: Experimental evidence shows that activation of the autonomic nervous system influences ventricular repolarization and, therefore, the QT interval on the ECG. To test the hypothesis that the QT interval is abnormal in autonomic dysfunction, we examined ECGs in patients with severe primary autonomic failure and in patients with congenital dopamine beta-hydroxylase (DbetaH) deficiency who are unable to synthesize norepinephrine and epinephrine. SUBJECTS AND METHODS: Maximal QT and rate-corrected QT (QTc) intervals and adjusted QTc dispersion [(maximal QTc - minimum QTc on 12 lead ECG)/square root of the number of leads measured] were determined in blinded fashion from ECGs of 67 patients with primary autonomic failure (36 patients with multiple system atrophy [MSA], and 31 patients with pure autonomic failure [PAF]) and 17 age- and sex-matched healthy controls. ECGs of 5 patients with congenital DbetaH deficiency and 6 age- and sex-matched controls were also analyzed. RESULTS: Patients with MSA and PAF had significantly prolonged maximum QTc intervals (492+/-58 ms(1/2) and 502+/-61 ms(1/2) [mean +/- SD]), respectively, compared with controls (450+/-18 ms(1/2), P parasympathetic and sympathetic failure have abnormally prolonged QT interval and increased QT dispersion. However, QT interval in patients with congenital DbetaH deficiency was not significantly different from controls. It is possible, therefore, that QT abnormalities in patients with primary autonomic failure are not solely caused by lesions of the sympathetic nervous system, and that the parasympathetic nervous system is likely to have a modulatory role in ventricular repolarization.

  4. Computer-based analysis of cardiac state using entropies, recurrence plots and Poincare geometry.

    Science.gov (United States)

    Chua, K C; Chandran, V; Acharya, U R; Lim, C M

    2008-01-01

    Heart rate variability refers to the regulation of the sinoatrial node, the natural pacemaker of the heart by the sympathetic and parasympathetic branches of the autonomic nervous system. Heart rate variability is important because it provides a window to observe the heart's ability to respond to normal regulatory impulses that affect its rhythm. A computer-based intelligent system for analysis of cardiac states is very useful in diagnostics and disease management. Parameters are extracted from the heart rate signals and analysed using computers for diagnostics. This paper describes the analysis of normal and seven types of cardiac abnormal signals using approximate entropy (ApEn), sample entropy (SampEn), recurrence plots and Poincare plot patterns. Ranges of these parameters for various cardiac abnormalities are presented with an accuracy of more than 95%. Among the two entropies, ApEn showed better performance for all the cardiac abnormalities. Typical Poincare and recurrence plots are shown for various cardiac abnormalities.

  5. A computational investigation of cardiac caveolae as a source of persistent sodium current

    Directory of Open Access Journals (Sweden)

    Ian M. Besse

    2011-11-01

    Full Text Available Recent studies of cholesterol-rich membrane microdomains, called caveolae, reveal that caveolae are reservoirs of recruitable sodium ion channels. Caveolar channels constitute a substantial and previously unrecognized source of sodium current in cardiac cells. In this paper we model for the first time caveolar sodium currents and their contributions to cardiac action potential morphology. We show that the beta-agonist-induced opening of caveolae may have substantial impacts on peak overshoot, maximum upstroke velocity, and ultimately conduction velocity. Additionally, we show that prolonged action potentials and the formation of potentially arrhythmogenic afterdepolarizations, can arise if caveolae open intermittently throughout the action potential. Our simulations suggest that there may exist routes to delayed repolarization, and the arrhythmias associated with such delays, that are independent of channelopathies.

  6. Heart rate, blood pressure and repolarization effects of an energy drink as compared to coffee.

    Science.gov (United States)

    Brothers, R Matthew; Christmas, Kevin M; Patik, Jordan C; Bhella, Paul S

    2016-03-01

    The goal of this study was to investigate the impact of energy drinks on haemodynamic and cardiac physiology. Comparisons were made to coffee as well as water consumption. In Protocol #1 the caffeine content was normalized to body weight to represent a controlled environment. Heart rate, blood pressure and cardiac QTc interval were assessed in 15 participants, on 4 days, prior to and for 6·5 h postconsumption of (i) energy drink (2 mg caffeine per kg body weight; low dose), (ii) energy drink (3 mg caffeine per kg body weight; medium dose), (iii) coffee (2 mg caffeine per kg body weight) and (iv) 250 ml water. In Protocol #2, the beverages were consumed in volumes that they are purchased to represent real-life conditions. The aforementioned measurements were repeated in 15 participants following (i) 1 16 oz can of energy drink (16 oz Monster), (ii) 1 24 oz can of energy drink (24 oz Monster), (iii) 1 packet of Keurig K-Cup Starbucks coffee (coffee) and (iv) 250 ml water. The order of the beverages was performed in a randomized double-blinded fashion. For both protocols, QTc interval, heart rate and systolic blood pressure were unchanged in any condition (P>0·05). Diastolic blood pressure and mean blood pressure were slightly elevated in Protocol #1 (P0·05). These findings suggest that acute consumption of these commonly consumed beverages has no negative effect on cardiac QTc interval.

  7. CAPSAICIN SUPPLEMENTATION FAILS TO MODULATE AUTONOMIC AND CARDIAC ELECTROPHYSIOLOGIC ACTIVITY DURING EXERCISE IN THE OBESE: WITH VARIANTS OF UCP2 AND UCP3 POLYMORPHISM

    Directory of Open Access Journals (Sweden)

    Ki Ok Shin

    2008-09-01

    Full Text Available We investigated the effects of capsaicin supplementation (150mg on alterations of autonomic nervous system (ANS activity associated with adverse effects of cardiac depolarization-repolarization intervals during aerobic exercise in obese humans. Nine obese males (26.1 ± 1.5 yrs volunteered between study designed. The cardiac ANS activities evaluated by means of heart rate variability of power spectral analysis and cardiac QT interval were continuously measured during 5-min rest and 30-min exercise at 50% of maximal ventilation threshold (50%VTmax on stationary ergometer with placebo (CON or capsaicin (CAP oral administration chosen at random. The uncoupling protein (UCP 2 and UCP 3 genetic variants of the subjects were analyzed by noninvasive genotyping method from collecting buccal mucosa cells. The results indicated that there were no significant differences in cardiac ANS activities during rest and exercise between CON and CAP trials. Although no significant difference, A/A allele of UCP2 polymorphism showed a reduced sympathetic nervous system (SNS index activity compared to G/G + G/A allele during exercise intervention in our subjects. On the other hand, the data on cardiac QT interval showed no significant difference, indicating that oral administration of capsaicin did not cause any adverse effect on cardiac depolarization-repolarization. In conclusion, our results suggest that capsaicin supplementation 1 h before exercise intervention has no effect on cardiac ANS activities and cardiac electrical stability during exercise in obese individuals. Further studies should also consider genetic variants for exercise efficacy against obesity

  8. Cardiac MRI in Athletes

    NARCIS (Netherlands)

    Luijkx, T.

    2012-01-01

    Cardiac magnetic resonance imaging (CMR) is often used in athletes to image cardiac anatomy and function and is increasingly requested in the context of screening for pathology that can cause sudden cardiac death (SCD). In this thesis, patterns of cardiac adaptation to sports are investigated with C

  9. Pharmacological inhibition of I-K1 by PA-6 in isolated rat hearts affects ventricular repolarization and refractoriness

    DEFF Research Database (Denmark)

    Skarsfeldt, Mark A.; Carstensen, Helena; Skibsbye, Lasse;

    2016-01-01

    .1 14.7 msec, 67%, P ventricular fibrillation was observed in two of six hearts. Neither atrial ERP nor duration of atrial fibrillation was altered following PA-6 application. The results show that pharmacological inhibition...... cycle length, and ventricular effective refractory period were determined following 200 nmol/L PA-6 perfusion. 200 nmol/L PA-6 resulted in a significant timelatency in drug effect on the IK1 current expressed in HEK-293 cells, giving rise to a maximal effect at 20 min. In the Langendorff-perfused heart...... experiments, PA-6 prolonged the ventricular action potential duration at 90% repolarization (from 41.8 6.5 msec to 72.6 21.1 msec, 74% compared to baseline, P ventricular effective refractory period compared to baseline (from 34.8 4.6 msec to 58...

  10. Resilient RTN fast spiking in Kv3.1 null mice suggests redundancy in the action potential repolarization mechanism.

    Science.gov (United States)

    Porcello, Darrell M; Ho, Chi Shun; Joho, Rolf H; Huguenard, John R

    2002-03-01

    Fast spiking (FS), GABAergic neurons of the reticular thalamic nucleus (RTN) are capable of firing high-frequency trains of brief action potentials, with little adaptation. Studies in recombinant systems have shown that high-voltage-activated K(+) channels containing the Kv3.1 and/or Kv3.2 subunits display biophysical properties that may contribute to the FS phenotype. Given that RTN expresses high levels of Kv3.1, with little or no Kv3.2, we tested whether this subunit was required for the fast action potential repolarization mechanism essential to the FS phenotype. Single- and multiple-action potentials were recorded using whole-cell current clamp in RTN neurons from brain slices of wild-type and Kv3.1-deficient mice. At 23 degrees C, action potentials recorded from homozygous Kv3.1 deficient mice (Kv3.1(-/-)) compared with their wild-type (Kv3.1(+/+)) counterparts had reduced amplitudes (-6%) and fast after-hyperpolarizations (-16%). At 34 degrees C, action potentials in Kv3.1(-/-) mice had increased duration (21%) due to a reduced rate of repolarization (-30%) when compared with wild-type controls. Action potential trains in Kv3.1(-/-) were associated with a significantly greater spike decrement and broadening and a diminished firing frequency versus injected current relationship (F/I) at 34 degrees C. There was no change in either spike count or maximum instantaneous frequency during low-threshold Ca(2+) bursts in Kv3.1(-/-) RTN neurons at either temperature tested. Our findings show that Kv3.1 is not solely responsible for fast spikes or high-frequency firing in RTN neurons. This suggests genetic redundancy in the system, possibly in the form of other Kv3 members, which may suffice to maintain the FS phenotype in RTN neurons in the absence of Kv3.1.

  11. Over-phosphorylation of FKBP12.6, phospholamban,relating to exacerbation of cardiac arrhythmias and failure

    Institute of Scientific and Technical Information of China (English)

    De-zaiDAI

    2004-01-01

    AIM: Cardiac arrhythmias occur severely in diseased and failing hearts and remain an important cause of mortality in cardiovascular disorders. It was intended to explore mechanisms of abnormal ion channels underlying cardiac arrhythmias and failure and in responses to drug interventions. METHODS: Chronic infarction plus isoproterenol (ISO) medication or L-thyroxin (THY) repetitive medication promote cardiac remodeling and exaggerated

  12. [Hair shaft abnormalities].

    Science.gov (United States)

    Itin, P H; Düggelin, M

    2002-05-01

    Hair shaft disorders may lead to brittleness and uncombable hair. In general the hair feels dry and lusterless. Hair shaft abnormalities may occur as localized or generalized disorders. Genetic predisposition or exogenous factors are able to produce and maintain hair shaft abnormalities. In addition to an extensive history and physical examination the most important diagnostic examination to analyze a hair shaft problem is light microscopy. Therapy of hair shaft disorders should focus to the cause. In addition, minimizing traumatic influences to hair shafts, such as dry hair with an electric dryer, permanent waves and dyes is important. A short hair style is more suitable for such patients with hair shaft disorders.

  13. Abnormalities of gonadal differentiation.

    Science.gov (United States)

    Berkovitz, G D; Seeherunvong, T

    1998-04-01

    Gonadal differentiation involves a complex interplay of developmental pathways. The sex determining region Y (SRY) gene plays a key role in testis determination, but its interaction with other genes is less well understood. Abnormalities of gonadal differentiation result in a range of clinical problems. 46,XY complete gonadal dysgenesis is defined by an absence of testis determination. Subjects have female external genitalia and come to clinical attention because of delayed puberty. Individuals with 46,XY partial gonadal dysgenesis usually present in the newborn period for the valuation of ambiguous genitalia. Gonadal histology always shows an abnormality of seminiferous tubule formation. A diagnosis of 46,XY true hermaphroditism is made if the gonads contain well-formed testicular and ovarian elements. Despite the pivotal role of the SRY gene in testis development, mutations of SRY are unusual in subjects with a 46,XY karyotype and abnormal gonadal development. 46,XX maleness is defined by testis determination in an individual with a 46,XX karyotype. Most affected individuals have a phenotype similar to that of Klinefelter syndrome. In contrast, subjects with 46,XX true hermaphroditism usually present with ambiguous genitalia. The majority of subjects with 46,XX maleness have Y sequences including SRY in genomic DNA. However, only rare subjects with 46,XX true hermaphroditism have translocated sequences encoding SRY. Mosaicism and chimaerism involving the Y chromosome can also be associated with abnormal gonadal development. However, the vast majority of subjects with 45,X/46,XY mosaicism have normal testes and normal male external genitalia.

  14. Cortical Abnormalities in ADHD

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2003-12-01

    Full Text Available Grey-matter abnormalities at the cortical surface and regional brain size were mapped by high-resolution MRI and surface-based, computational image analytical techniques in a group of 27 children and adolescents with attention deficit hyperactivity disorder (ADHD and 46 controls, matched by age and sex, at the University of California at Los Angeles.

  15. Neurological abnormalities predict disability

    DEFF Research Database (Denmark)

    Poggesi, Anna; Gouw, Alida; van der Flier, Wiesje

    2014-01-01

    To investigate the role of neurological abnormalities and magnetic resonance imaging (MRI) lesions in predicting global functional decline in a cohort of initially independent-living elderly subjects. The Leukoaraiosis And DISability (LADIS) Study, involving 11 European centres, was primarily aimed...

  16. Lacrimal system abnormalities.

    Science.gov (United States)

    Moore, B D

    1994-03-01

    This report outlines several of the more important abnormalities of the lacrimal system in infants and young children. Although rare, alacrima can be a very difficult clinical problem to treat. The most common cause of alacrima is the Riley-Day syndrome. Nasolacrimal duct obstruction is a very common anomaly in children. The clinical appearance and treatment of this disorder are discussed.

  17. Hysteresis of electrocardiographic depolarization-repolarization intervals during dynamic physical exercise and subsequent recovery.

    Science.gov (United States)

    Lewis, M J; Short, A L

    2006-02-01

    The post-exercise electrocardiographic QT interval is shortened relative to that at similar heart rates during exercise or pre-exercise rest. This lag in QT adaptation to the recovering heart rate is described as "hysteresis". No previous studies have quantified the influence of ECG electrode placement on hysteresis following physical exercise. Six males and six females of similar age, mass and aerobic fitness undertook progressive sub-maximal bicycle exercise. A three-channel ECG was recorded continuously during pre-exercise, exercise and recovery. Beat-to-beat NN (cardiac interval) and QT(a) interval (Q wave onset to T wave apex) data were measured for each sinus heart beat. QT(a)-NN hysteresis was calculated as the difference in QT(a) magnitude at identical heart rates during the rest/exercise and post-exercise recovery periods. There were some significant (p ECG electrode placement in future investigations.

  18. The enhancement of cardiac toxicity by concomitant administration of Berberine and macrolides.

    Science.gov (United States)

    Zhi, Duo; Feng, Pan-Feng; Sun, Jia-Liang; Guo, Fengfeng; Zhang, Rui; Zhao, Xin; Li, Bao-Xin

    2015-08-30

    As is well-known, hERG plays an essential role in phase III repolarization of cardiac action potentials. Blocking of hERG channels can lead to LQTS. Inhibition of the metabolism of CYPs activities may elevate plasma levels, to further increase accumulation of drug on cardiac. The elevated serum levels may however elicit unexpected toxicities. Therefore, the inhibition tests of hERG and CYP are central to the preclinical studies because they may lead to severe cardiac toxicity. Berberine is widely used as an antibacterial agent and often combined with macrolides to treat gastropathy. Our objective was to assess cardiac toxicity during the combined use of Berberine with macrolides. (1) Azithromycin reduced hERG currents by accelerated channel inactivation. (2) The combination of Berberine with Azithromycin reduced hERG currents, producing an inhibitive effect stronger than use of a single drug alone, due to the high binding affinity for the onset of inactivation. (3) When cells were perfused concomitantly with Berberine and Clarithromycin, they showed a stronger inhibitive effect on hERG currents by decreasing the time constant for the onset of inactivation. (4) The combined administration of Berberine with Clarithromycin had a powerful inhibitive effect on CYP3A activities than use of a single drug alone. Collectively, these results demonstrated that concomitant use of Berberine with macrolides may require close monitoring because of potential drug toxicities, especially cardiac toxicity.

  19. Review Article of Cardiac Amyloidosis

    Directory of Open Access Journals (Sweden)

    Jittiporn PURATTANAMAL

    2010-06-01

    Full Text Available Cardiac amyloidosis is a term that means the deposit of abnormal proteins in the myocardium leading to global thickening of the heart walls. The clinical character is that of infiltrative cardiomyopathy. AL amyloidosis is the most common type that involves cardiac failure. Cardiac amyloid precedes clinical congestive heart failure, especially right-sided heart failure. Laboratory investigations have identified the amyloid fibril proteins deposited in the organ tissues. Immunofixation tests are the most sensitive that recognize the paraprotein mean light chain protein or immunoglobulin subtype deposit. Prognosis is poor if AL amyloidosis is untreated. Treatment of systemic involvement in AL amyloidosis is via chemotherapy such as melphalan and prednisolone. UK experts have reported the results of treatment in AL amyloidosis. Regardless of the use of adjunctive chemotherapy, the five-year survival after heart transplantation was generally poorer for AL (20 % at five years, but similar for non-AL amyloidosis (64 % at five years, than heart transplants in other cases. Progression of the systemic disease contributed to increased mortality. A specific treatment that increases the chances of survival is unknown.

  20. Inherited arrhythmias: The cardiac channelopathies

    Directory of Open Access Journals (Sweden)

    Shashank P Behere

    2015-01-01

    Full Text Available Ion channels in the myocardial cellular membrane are responsible for allowing the cardiac action potential. Genetic abnormalities in these channels can predispose to life-threatening arrhythmias. We discuss the basic science of the cardiac action potential; outline the different clinical entities, including information regarding overlapping diagnoses, touching upon relevant genetics, new innovations in screening, diagnosis, risk stratification, and management. The special considerations of sudden unexplained death and sudden infant death syndrome are discussed. Scientists and clinicians continue to reconcile the rapidly growing body of knowledge regarding the molecular mechanisms and genetics while continuing to improve our understanding of the various clinical entities and their diagnosis and management in clinical setting. Two separate searches were run on the National Center for Biotechnology Information′s website. The first using the term cardiac channelopathies was run on the PubMed database using filters for time (published in past 5 years and age (birth-18 years, yielding 47 results. The second search using the medical subject headings (MeSH database with the search terms "Long QT Syndrome" (MeSH and "Short QT Syndrome" (MeSH and "Brugada Syndrome" (MeSH and "Catecholaminergic Polymorphic Ventricular Tachycardia" (MeSH, applying the same filters yielded 467 results. The abstracts of these articles were studied, and the articles were categorized and organized. Articles of relevance were read in full. As and where applicable, relevant references and citations from the primary articles where further explored and read in full.

  1. Ion channelopathy and hyperphosphorylation contributing to cardiac arrhythmias

    Institute of Scientific and Technical Information of China (English)

    De-zai DAI; Feng YU

    2005-01-01

    The occurrence of cardiac arrhythmias is related to the abnormality of ion channels not only in sarcolemma but also in the sarcoplasmic reticulum, which regulates the process of calcium release and up-take intracellularly. Patterns of ion channelopathy in the sarcolemma can be divided into single channel disorder from gene mutations and multiple channels disorder in a diseased hypertrophied heart. Abnormal RyR2, FKBP12.6, SERCA2a, and PLB are also involved in the initiation of cardiac arrhythmias. Maladjustment by hyperphosphorylation on the ion channels in the sarcolemma and RyR2-FKBP12.6 and SERCA2a-PLB is discussed. Hyperphosphorylation, which is the main abnormality upstream to ion channels, can be targeted for suppressing the deterioration of ion channelopathy in terms of new drug discovery in the treatment and prevention of malignant cardiac arrhythmias.

  2. IS CONSANGUINEOUS MARRIAGE RESPONSIBLE FOR CONGENITAL CARDIAC AND EXTRA-CARDIAC ANOMALIES?

    Directory of Open Access Journals (Sweden)

    Nutan Nalini

    2016-03-01

    Full Text Available BACKGROUND This article is about the stillbirth in which we found significant numbers of cardiac as well as extracardiac defects, in combination or separately. In this article, we would like to emphasize the anomalies found in consanguineous marriages. AIM To correlate the prevalence of cardiac as well as extracardiac anomalies in consanguineous marriages. Especially, here we would like to focus on the cardiac lesions. MATERIAL AND METHOD The study was carried out in 44 still birth foetuses with detailed account of parentage. Significant number of cases with cardiac and extracardiac anomalies was found. RESULTS Out of total 44 stillbirth foetuses, 13 stillbirths were from consanguineous marriages in which 09 had cardiac anomalies. Interrupted aortic arch-02, Abnormal origin of right Subclavian artery- 01, Tetralogy of Fallot- 01, VSD- 04, ASD-01. The extra cardiac findings included Gastroschisis-01, Anencephaly with spina bifida-01, cleft lip/palate-01, polydactyly and syndactyly of ring and little finger-01, limb deformity-01, hydrocephalus-01, craniothoracopagus-01. CONCLUSION Considering the high incidence of cardiac and extracardiac anomalies in consanguineous parentage we must try to create an awareness to avoid the practice of consanguineous marriages in society.

  3. Cardiac troponin T mutations in Chinese patients with hypertrophic cardiomyopathy

    Institute of Scientific and Technical Information of China (English)

    吴恒芳; 杨笛; 万文辉; 卞智萍; 徐晋丹; 马文珠; 张寄南

    2004-01-01

    @@ Hypertrophic cardiomyopathy (HCM) is a myocardial disorder characterized by unexplained ventricular hypertrophy and myofibrillar disarray, with a prevalence of about 0.2% in general population. HCM is associated with gene abnormalities. Nearly 200 mutations have been described in ten genes in patients with HCM.1 Cardiac troponin T (cTnT) is an essential component of the troponin complex and plays a central role in the calcium regulation of contractions in cardiac myocytes

  4. Nitrofurantoin and congenital abnormalities

    DEFF Research Database (Denmark)

    Czeizel, A.E.; Rockenbauer, M.; Sørensen, Henrik Toft;

    2001-01-01

    Objective: To study human teratogenic potential of oral nitrofurantoin treatment during pregnancy. Materials and Methods: Pair analysis of cases with congenital abnormalities and matched population controls in the population-based dataset of the Hungarian Case-Control Surveillance of Congenital...... or fetuses with Down’s syndrome (patient controls), 23 (2.8%) pregnant women were treated with nitrofurantoin. The above differences between population controls and cases may be connected with recall bias, because the case-control pair analysis did not indicate a teratogenic potential of nitrofurantoin use...... during the second and the third months of gestation, i.e. in the critical period for major congenital abnormalities. Conclusion: Treatment with nitrofurantoin during pregnancy does not present detectable teratogenic risk to the fetus....

  5. Significance of Cardiac Rehabilitation on Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Krutika Gajjar

    2012-06-01

    Full Text Available Considering the high mortality and morbidity rate associated with cardiovascular diseases, Cardiacrehabilitation (CR is regarded for prevention and management of cardiovascular diseases. CR servicesare generally provided in an outpatient as comprehensive, long-term programs involving medicalevaluation, prescribed exercise, cardiac risk factor modification, education and counseling. This includesnutritional therapies, weight loss program management of lipid abnormalities with diet and medication,blood pressure control, diabetes management and stress management. The exercise component of a totalapproach to rehabilitation helps to overcome the fears and anxieties that so many people experience aftera heart attack. Aerobic exercise training program improves cardiovascular fitness in both healthyindividual and cardiac patients. Cardiac rehabilitation prevents and treat cardiovascular disease, reducescardiac risk factors, improving patient’s exercise capacity and enhancing quality of life. Aerobicexercise with intensity of approximately 60 to 70% of the maximal heart rate for 30 to 60 minutes, 3 to 4times a week, for 4 to 6 weeks enhances exercise capacity.

  6. Extracorporeal life support in pediatric cardiac patients

    Directory of Open Access Journals (Sweden)

    Matteo Di NARDO

    2016-10-01

    Full Text Available Extracorporeal Life Support (ECLS is a valuable tool in the management of neonates and older children with severe cardiac or respiratory failure. In this review, we focus on ECLS when used for neonatal and pediatric cardiac disease. Strict selection of patients and timely deployment are necessary to optimize outcomes. Although every attempt should be made to deploy ECLS urgently rather than emergently, extracorporeal cardiopulmonary resuscitation (ECPR is being increasingly used and reasonable survival rates have been achieved after initiation of ECLS during active compressions of the chest following in-hospital cardiac arrest. Contraindications to ECLS are falling over time, although lethal chromosomal abnormalities, severe irreversible brain injury, and extremely low gestational age and weight (<32 weeks gestation or <1.5 kg remain firm contraindications.

  7. Uncertainty Visualization in Forward and Inverse Cardiac Models.

    Science.gov (United States)

    Burton, Brett M; Erem, Burak; Potter, Kristin; Rosen, Paul; Johnson, Chris R; Brooks, Dana H; Macleod, Rob S

    2013-01-01

    Quantification and visualization of uncertainty in cardiac forward and inverse problems with complex geometries is subject to various challenges. Specific to visualization is the observation that occlusion and clutter obscure important regions of interest, making visual assessment difficult. In order to overcome these limitations in uncertainty visualization, we have developed and implemented a collection of novel approaches. To highlight the utility of these techniques, we evaluated the uncertainty associated with two examples of modeling myocardial activity. In one case we studied cardiac potentials during the repolarization phase as a function of variability in tissue conductivities of the ischemic heart (forward case). In a second case, we evaluated uncertainty in reconstructed activation times on the epicardium resulting from variation in the control parameter of Tikhonov regularization (inverse case). To overcome difficulties associated with uncertainty visualization, we implemented linked-view windows and interactive animation to the two respective cases. Through dimensionality reduction and superimposed mean and standard deviation measures over time, we were able to display key features in large ensembles of data and highlight regions of interest where larger uncertainties exist.

  8. Differential Diagnosis of Cardiac Malposition by Fetal Echocardiography

    Institute of Scientific and Technical Information of China (English)

    Ying WU; Feng TAO; Tao LIU; Ling ZANG; Shi-long LIU

    2009-01-01

    Objectives To explore the method and operating skill of fetal echocardiography in diagnosing cardiac malposition. Methods 91 consecutive fetuses were studied (control: 50 cases, cardiac malposition : 41 cases) between 2003 and 2008. The position of fetal heart was evaluated according to the fetal posture and the visceral situs by fetal routine scan-ning. The detailed echocardiography should be performed in the differential diagnosis of cardiac lesions when the heart was found to be abnormal position. Results In the control group, all fetuses were levocardia. 39 cases of cardiac mal-positions were detected by fetal echocardiography, included 25 fetuses with dextrocardia, 6 mesocard, 5 with levover-sion of heart, 3 common heart of conjoined twins and 2 extrathorax heart. Two of dextroversion were missed by fetal routine scanning, but found by autopsy or operation after birth. Conclusions When the abnormal visceral situs was found by fetal routine scanning, there is exceedingly high incidence of cardiac malpositions. Proficiently operating skill of fetal echocardiography is helpful to detect abnormal fetal cardiac position.

  9. Cardiac tamponade (image)

    Science.gov (United States)

    Cardiac tamponade is a condition involving compression of the heart caused by blood or fluid accumulation in the space ... they cannot adequately fill or pump blood. Cardiac tamponade is an emergency condition that requires hospitalization.

  10. What Is Cardiac Rehabilitation?

    Science.gov (United States)

    ANSWERS by heart Treatments + Tests What Is Cardiac Rehabilitation? A cardiac rehabilitation (rehab) program takes place in a hospital or ... special help in making lifestyle changes. During your rehabilitation program you’ll… • Have a medical evaluation to ...

  11. [Molecular abnormalities in lymphomas].

    Science.gov (United States)

    Delsol, G

    2010-11-01

    Numerous molecular abnormalities have been described in lymphomas. They are of diagnostic and prognostic value and are taken into account for the WHO classification of these tumors. They also shed some light on the underlying molecular mechanisms involved in lymphomas. Overall, four types of molecular abnormalities are involved: mutations, translocations, amplifications and deletions of tumor suppressor genes. Several techniques are available to detect these molecular anomalies: conventional cytogenetic analysis, multicolor FISH, CGH array or gene expression profiling using DNA microarrays. In some lymphomas, genetic abnormalities are responsible for the expression of an abnormal protein (e.g. tyrosine-kinase, transcription factor) detectable by immunohistochemistry. In the present review, molecular abnormalities observed in the most frequent B, T or NK cell lymphomas are discussed. In the broad spectrum of diffuse large B-cell lymphomas microarray analysis shows mostly two subgroups of tumors, one with gene expression signature corresponding to germinal center B-cell-like (GCB: CD10+, BCL6 [B-Cell Lymphoma 6]+, centerine+, MUM1-) and a subgroup expressing an activated B-cell-like signature (ABC: CD10-, BCL6-, centerine-, MUM1+). Among other B-cell lymphomas with well characterized molecular abnormalies are follicular lymphoma (BCL2 deregulation), MALT lymphoma (Mucosa Associated Lymphoid Tissue) [API2-MALT1 (mucosa-associated-lymphoid-tissue-lymphoma-translocation-gene1) fusion protein or deregulation BCL10, MALT1, FOXP1. MALT1 transcription factors], mantle cell lymphoma (cycline D1 [CCND1] overexpression) and Burkitt lymphoma (c-Myc expression). Except for ALK (anaplastic lymphoma kinase)-positive anaplastic large cell lymphoma, well characterized molecular anomalies are rare in lymphomas developed from T or NK cells. Peripheral T cell lymphomas not otherwise specified are a heterogeneous group of tumors with frequent but not recurrent molecular abnormalities

  12. Feeling Abnormal: Simulation of Deviancy in Abnormal and Exceptionality Courses.

    Science.gov (United States)

    Fernald, Charles D.

    1980-01-01

    Describes activity in which student in abnormal psychology and psychology of exceptional children classes personally experience being judged abnormal. The experience allows the students to remember relevant research, become sensitized to the feelings of individuals classified as deviant, and use caution in classifying individuals as abnormal.…

  13. Cardiac involvement in children with neuro-muscular disorders

    Directory of Open Access Journals (Sweden)

    E. N. Arkhipova

    2015-01-01

    Full Text Available Many inherited neuromuscular disorders include cardiac involvement as a typical clinical feature. Among the most common of them is the group of muscular dystrophies. Dilated cardiomyopathy, ventricular arrhythmias, atrial fibrillations, atrioventricular and intraventricular conduction abnormalities, and sudden cardiac death are well known pathological findings in Duchenne muscular dystrophies, myotonic dystrophy type I and 2, Emery-Dreifuss muscular dystrophies and different types of limb-girdle muscular dystrophies and other disorders. Detection of cardiac pathology in patients with different muscular dystrophies is possible with ECG, echocardiography and cardiovascular magnetic resonance imaging, which are recommended for screening and early cardioprotective treatment.

  14. Genetic disorders with both hearing loss and cardiovascular abnormalities.

    Science.gov (United States)

    Belmont, John W; Craigen, William; Martinez, Hugo; Jefferies, John Lynn

    2011-01-01

    There has been a growing appreciation for conditions that affect hearing and which are accompanied by significant cardiovascular disorders. In this chapter we consider several broad classes of conditions including deafness due to abnormal structural development of the inner ear, those with physiological abnormalities in the inner ear sensory apparatus, and conditions with progressive loss of function of sensory cells or middle ear functions. Because of shared developmental controls, inner ear malformations are often associated with congenital heart defects and can be part of complex syndromes that affect other organs and neurodevelopmental outcome. Physiological disorders of the hair cells can lead to hearing loss and can be associated with cardiac arrhythmias, especially long QT syndrome. In addition, cellular energy defects such as mitochondrial disorders can affect maintenance of hair cells and are often associated with cardiomyopathy. Lysosomal storage diseases and other disorders affecting connective tissue can lead to chronic middle ear disease, with conductive hearing loss and also cause cardiac valve disease and/or cardiomyopathy. The genetic basis for these conditions is heterogeneous and includes chromosomal/genomic disorders, de novo dominant mutations, and familial dominant, autosomal-recessive, and mitochondrial (matrilineal) inheritance. Taken together, there are more than 100 individual genes implicated in genetic hearing impairment that are also associated with congenital and/or progressive cardiac abnormalities. These genes encode transcription factors, chromatin remodeling factors, components of signal transduction pathways, ion channels, mitochondrial proteins and assembly factors, extracellular matrix proteins, and enzymes involved in lysosomal functions.

  15. Cardiac sodium channelopathies

    NARCIS (Netherlands)

    Amin, A.S.; Asghari-Roodsari, A.; Tan, H.L.

    2010-01-01

    Cardiac sodium channel are protein complexes that are expressed in the sarcolemma of cardiomyocytes to carry a large inward depolarizing current (I-Na) during phase 0 of the cardiac action potential. The importance of I-Na for normal cardiac electrical activity is reflected by the high incidence of

  16. Estudo cardiológico longitudinal em crianças expostas ao vírus da imunodeficiência humana tipo 1 por via perinatal Cardiac longitudinal study of children perinatally exposed to human immunodeficiency virus type 1

    Directory of Open Access Journals (Sweden)

    Maria Suely Bezerra Diógenes

    2005-10-01

    natural history in children perinatally exposed to HIV-1. METHODS: Eighty-four children exposed to HIV-1 were evaluated by serial clinical, electrocardiographic (ECG, and Doppler-echocardiographic (ECHO examinations. RESULTS: Group I - (seroreversion - 43 children (51.2%. Absence of clinical abnormalities. ECG: incomplete right bundle branch block (RBBB 5 cases. ECHO: atrial septal defect (ASD and ventricular septal defect (VSD - 1 case each. Group II - 41 HIV-infected children (48.8%, of whom 51.2% were found to have cardiac abnormalities. Asymptomatic or mildly symptomatic children without immunosuppression: no clinical and echocardiographic abnormalities; ECG: incomplete right bundle branch block (RBBB - (2 cases. Children with moderate and severe symptoms and immunological impairment: the following abnormalities were found: 1 clinical (31.7%-isolated tachycardia (1 case, congestive heart failure (12 cases. 2 electrocardiographic (43.9%- sinus tachycardia associated with other abnormalities (10 cases, incomplete right bundle branch block (5 cases, left anterior hemiblock (1 case, right anterior hemiblock (1 case, changes in ventricular repolarization (11 cases, right ventricular overload (2 cases, left ventricular overload (1 case, right QRS axis deviation (1 case, and arrhythmias (3 cases. 3 echocardiographic (26.8%- dilated cardiomyopathy (5 cases, pericardial effusion with tamponade (2 cases, pulmonary hypertension (2 cases, and mitral valve prolapse (1 case. CONCLUSION: Cardiac involvement was a characteristic of the HIV-infected group. Higher prevalence of abnormalities was found among children belonging to the most advanced clinical and immunological category. The most commonly observed clinical, electrocardiographic and echocardiographic findings were congestive heart failure (CHF, changes in ventricular repolarization, and dilated cardiomyopathy, respectively. The latter was reversible in one case. Electrocardiogram changes were significantly more frequent than

  17. Enabling microscale and nanoscale approaches for bioengineered cardiac tissue.

    Science.gov (United States)

    Chan, Vincent; Raman, Ritu; Cvetkovic, Caroline; Bashir, Rashid

    2013-03-26

    In this issue of ACS Nano, Shin et al. present their finding that the addition of carbon nanotubes (CNT) in gelatin methacrylate (GelMA) results in improved functionality of bioengineered cardiac tissue. These CNT-GelMA hybrid materials demonstrate cardiac tissue with enhanced electrophysiological performance; improved mechanical integrity; better cell adhesion, viability, uniformity, and organization; increased beating rate and lowered excitation threshold; and protective effects against cardio-inhibitory and cardio-toxic drugs. In this Perspective, we outline recent progress in cardiac tissue engineering and prospects for future development. Bioengineered cardiac tissues can be used to build "heart-on-a-chip" devices for drug safety and efficacy testing, fabricate bioactuators for biointegrated robotics and reverse-engineered life forms, treat abnormal cardiac rhythms, and perhaps one day cure heart disease with tissue and organ transplants.

  18. [Sudden cardiac death in individuals with normal hearts: an update].

    Science.gov (United States)

    González-Melchor, Laila; Villarreal-Molina, Teresa; Iturralde-Torres, Pedro; Medeiros-Domingo, Argelia

    2014-01-01

    Sudden death (SD) is a tragic event and a world-wide health problem. Every year, near 4-5 million people experience SD. SD is defined as the death occurred in 1h after the onset of symptoms in a person without previous signs of fatality. It can be named "recovered SD" when the case received medical attention, cardiac reanimation effective defibrillation or both, surviving the fatal arrhythmia. Cardiac channelopathies are a group of diseases characterized by abnormal ion channel function due to genetic mutations in ion channel genes, providing increased susceptibility to develop cardiac arrhythmias and SD. Usually the death occurs before 40 years of age and in the autopsy the heart is normal. In this review we discuss the main cardiac channelopathies involved in sudden cardiac death along with current management of cases and family members that have experienced such tragic event.

  19. Strategies for the prevention of sudden cardiac death during sports.

    Science.gov (United States)

    Corrado, Domenico; Drezner, Jonathan; Basso, Cristina; Pelliccia, Antonio; Thiene, Gaetano

    2011-04-01

    Sudden cardiac death of a young athlete is the most tragic event in sports and devastates the family, the sports medicine team, and the local community. Such a fatality represents the first manifestation of cardiac disease in up to 80% of young athletes who remain asymptomatic before sudden cardiac arrest occurs; this explains the limited power of screening modalities based solely on history and physical examination. The long-running Italian experience showed that electrocardiogram (ECG) screening definitively improves the sensitivity of pre-participation evaluation for heart diseases and substantially reduces the risk of death in the athletic field (primary prevention). However, some cardiac conditions, such as coronary artery diseases, present no abnormalities on 12-lead ECG. Moreover, cardiac arrest due to non-penetrating chest injury (commotio cordis) cannot be prevented by screening. This justifies the efforts for implementing programmes of early external defibrillation of unpredictable arrhythmic cardiac arrest. This article reviews the epidemiology of sudden cardiac arrest in the athlete in terms of incidence, sport-related risk, underlying causes, and the currently available prevention programmes such as pre-participation screening and early external defibrillation by using automated external defibrillators. The best strategy is to combine synergistically primary prevention of sudden cardiac death by pre-participation identification of athletes affected by at-risk cardiomyopathies and secondary prevention with back-up defibrillation of unpredictable sudden cardiac arrest on the athletic field.

  20. Cardiac muscarinic receptor overexpression in sudden infant death syndrome.

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    Angelo Livolsi

    Full Text Available BACKGROUND: Sudden infant death syndrome (SIDS remains the leading cause of death among infants less than 1 year of age. Disturbed expression of some neurotransmitters and their receptors has been shown in the central nervous system of SIDS victims but no biological abnormality of the peripheral vago-cardiac system has been demonstrated to date. The present study aimed to seek vago-cardiac abnormalities in SIDS victims. The cardiac level of expression of muscarinic receptors, as well as acetylcholinesterase enzyme activity were investigated. METHODOLOGY/PRINCIPAL FINDINGS: Left ventricular samples and blood samples were obtained from autopsies of SIDS and children deceased from non cardiac causes. Binding experiments performed with [(3H]NMS, a selective muscarinic ligand, in cardiac membrane preparations showed that the density of cardiac muscarinic receptors was increased as shown by a more than doubled B(max value in SIDS (n = 9 SIDS versus 8 controls. On average, the erythrocyte acetylcholinesterase enzyme activity was also significantly increased (n = 9 SIDS versus 11 controls. CONCLUSIONS: In the present study, it has been shown for the first time that cardiac muscarinic receptor overexpression is associated with SIDS. The increase of acetylcholinesterase enzyme activity appears as a possible regulatory mechanism.

  1. In Silico Investigation into Cellular Mechanisms of Cardiac Alternans in Myocardial Ischemia

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    Jiaqi Liu

    2016-01-01

    Full Text Available Myocardial ischemia is associated with pathophysiological conditions such as hyperkalemia, acidosis, and hypoxia. These physiological disorders may lead to changes on the functions of ionic channels, which in turn form the basis for cardiac alternans. In this paper, we investigated the roles of hyperkalemia and calcium handling components played in the genesis of alternans in ischemia at the cellular level by using computational simulations. The results show that hyperkalemic reduced cell excitability and delayed recovery from inactivation of depolarization currents. The inactivation time constant τf of L-type calcium current (ICaL increased obviously in hyperkalemia. One cycle length was not enough for ICaL to recover completely. Alternans developed as a result of ICaL responding to stimulation every other beat. Sarcoplasmic reticulum calcium-ATPase (SERCA2a function decreased in ischemia. This change resulted in intracellular Ca (Cai alternans of small magnitude. A strong Na+-Ca2+ exchange current (INCX increased the magnitude of Cai alternans, leading to APD alternans through excitation-contraction coupling. Some alternated repolarization currents contributed to this repolarization alternans.

  2. In Silico Investigation into Cellular Mechanisms of Cardiac Alternans in Myocardial Ischemia

    Science.gov (United States)

    Liu, Jiaqi; Zhao, Xiaopeng

    2016-01-01

    Myocardial ischemia is associated with pathophysiological conditions such as hyperkalemia, acidosis, and hypoxia. These physiological disorders may lead to changes on the functions of ionic channels, which in turn form the basis for cardiac alternans. In this paper, we investigated the roles of hyperkalemia and calcium handling components played in the genesis of alternans in ischemia at the cellular level by using computational simulations. The results show that hyperkalemic reduced cell excitability and delayed recovery from inactivation of depolarization currents. The inactivation time constant τf of L-type calcium current (ICaL) increased obviously in hyperkalemia. One cycle length was not enough for ICaL to recover completely. Alternans developed as a result of ICaL responding to stimulation every other beat. Sarcoplasmic reticulum calcium-ATPase (SERCA2a) function decreased in ischemia. This change resulted in intracellular Ca (Cai) alternans of small magnitude. A strong Na+-Ca2+ exchange current (INCX) increased the magnitude of Cai alternans, leading to APD alternans through excitation-contraction coupling. Some alternated repolarization currents contributed to this repolarization alternans. PMID:28070211

  3. Cardiac arrhythmia and heart failure: From bench to bedside

    Institute of Scientific and Technical Information of China (English)

    Yong-Fu Xiao

    2011-01-01

    @@ Cardiac arrhythmia is an abnormal rate and/or rhythm of a heart due to its abnormal electrical impulse origination and/or propagation.Various etiologies can cause arrhythnuas.Heart failure(HF)is a clinical syndrome due to an impaired heart that can not pump sufficient blood to meet the systemic metabolic needs.The common causes of HF include myocardial infarction,hypertension,valvular heart disease,and cardiomyopathy.

  4. Russia: An Abnormal Country

    Directory of Open Access Journals (Sweden)

    Steven Rosefielde

    2005-06-01

    Full Text Available Andrei Shleifer and Daniel Treisman recently rendered a summary verdict on the post Soviet Russian transition experience finding that the Federation had become a normal country with the west's assistance, and predicting that it would liberalize and develop further like other successful nations of its type. This essay demonstrates that they are mistaken on the first count, and are likely to be wrong on the second too. It shows factually, and on the norms elaborated by Pareto, Arrow and Bergson that Russia is an abnormal political economy unlikely to democratize, westernize or embrace free enterprise any time soon

  5. Abnormal ionization in sonoluminescence

    Science.gov (United States)

    Zhang, Wen-Juan; An, Yu

    2015-04-01

    Sonoluminescence is a complex phenomenon, the mechanism of which remains unclear. The present study reveals that an abnormal ionization process is likely to be present in the sonoluminescing bubble. To fit the experimental data of previous studies, we assume that the ionization energies of the molecules and atoms in the bubble decrease as the gas density increases and that the decrease of the ionization energy reaches about 60%-70% as the bubble flashes, which is difficult to explain by using previous models. Project supported by the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20120002110031) and the National Natural Science Foundation of China (Grant No. 11334005).

  6. Signs of cardiac autonomic imbalance and proarrhythmic remodeling in FTO deficient mice.

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    Luca Carnevali

    Full Text Available In humans, variants of the fat mass and obesity associated (FTO gene have recently been associated with obesity. However, the physiological function of FTO is not well defined. Previous investigations in mice have linked FTO deficiency to growth retardation, loss of white adipose tissue, increased energy metabolism and enhanced systemic sympathetic activation. In this study we investigated for the first time the effects of global knockout of the mouse FTO gene on cardiac function and its autonomic neural regulation. ECG recordings were acquired via radiotelemetry in homozygous knockout (n = 12 and wild-type (n = 8 mice during resting and stress conditions, and analyzed by means of time- and frequency-domain indexes of heart rate variability. In the same animals, cardiac electrophysiological properties (assessed by epicardial mapping and structural characteristics were investigated. Our data indicate that FTO knockout mice were characterized by (i higher heart rate values during resting and stress conditions, (ii heart rate variability changes (increased LF to HF ratio, (iii larger vulnerability to stress-induced tachyarrhythmias, (iv altered ventricular repolarization, and (v cardiac hypertrophy compared to wild-type counterparts. We conclude that FTO deficiency in mice leads to an imbalance of the autonomic neural modulation of cardiac function in the sympathetic direction and to a potentially proarrhythmic remodeling of electrical and structural properties of the heart.

  7. High-threshold, Kv3-like potassium currents in magnocellular neurosecretory neurons and their role in spike repolarization.

    Science.gov (United States)

    Shevchenko, Talent; Teruyama, Ryoichi; Armstrong, William E

    2004-11-01

    We identified Kv3-like high-threshold K+ currents in hypothalamic supraoptic neurons using whole cell recordings in hypothalamic slices and in acutely dissociated neurons. Tetraethylammonium (TEA)-sensitive currents (Kv3-like channels. In slices, tests with 0.01-0.7 mM TEA produced an IC50 of 200-300 nM for both fast and persistent currents. The fast transient current was similar to currents associated with the expression of Kv3.4 subunits, given that it was sensitive to BDS-I (100 nM). The persistent TEA-sensitive current appeared similar to those attributed to Kv3.1/3.2 subunits. Although qualitatively similar, oxytocin (OT) and vasopressin (VP) neurons in slices differed in the stronger presence of persistent current in VP neurons. In both cell types, the IC50 for TEA-induced spike broadening was similar to that observed for current suppression in voltage clamp. However, TEA had a greater effect on the spike width of VP neurons than of OT neurons. Immunochemical studies revealed a stronger expression of the Kv3.1b alpha-subunit in VP neurons, which may be related to the greater importance of this current type in VP spike repolarization. Because OT and VP neurons are not considered fast firing, but do exhibit frequency- and calcium-dependent spike broadening, Kv3-like currents may be important for maintaining spike width and calcium influx within acceptable limits during repetitive firing.

  8. Kv3.4 subunits enhance the repolarizing efficiency of Kv3.1 channels in fast-spiking neurons.

    Science.gov (United States)

    Baranauskas, Gytis; Tkatch, Tatiana; Nagata, Keiichi; Yeh, Jay Z; Surmeier, D James

    2003-03-01

    Neurons with the capacity to discharge at high rates--'fast-spiking' (FS) neurons--are critical participants in central motor and sensory circuits. It is widely accepted that K+ channels with Kv3.1 or Kv3.2 subunits underlie fast, delayed-rectifier (DR) currents that endow neurons with this FS ability. Expression of these subunits in heterologous systems, however, yields channels that open at more depolarized potentials than do native Kv3 family channels, suggesting that they differ. One possibility is that native channels incorporate a subunit that modifies gating. Molecular, electrophysiological and pharmacological studies reported here suggest that a splice variant of the Kv3.4 subunit coassembles with Kv3.1 subunits in rat brain FS neurons. Coassembly enhances the spike repolarizing efficiency of the channels, thereby reducing spike duration and enabling higher repetitive spike rates. These results suggest that manipulation of K3.4 subunit expression could be a useful means of controlling the dynamic range of FS neurons.

  9. Somatic membrane potential and Kv1 channels control spike repolarization in cortical axon collaterals and presynaptic boutons.

    Science.gov (United States)

    Foust, Amanda J; Yu, Yuguo; Popovic, Marko; Zecevic, Dejan; McCormick, David A

    2011-10-26

    The shape of action potentials invading presynaptic terminals, which can vary significantly from spike waveforms recorded at the soma, may critically influence the probability of synaptic neurotransmitter release. Revealing the conductances that determine spike shape in presynaptic boutons is important for understanding how changes in the electrochemical context in which a spike is generated, such as subthreshold depolarization spreading from the soma, can modulate synaptic strength. Utilizing recent improvements in the signal-to-noise ratio of voltage-sensitive dye imaging in mouse brain slices, we demonstrate that intracortical axon collaterals and en passant presynaptic terminals of layer 5 pyramidal cells exhibit a high density of Kv1 subunit-containing ion channels, which generate a slowly inactivating K(+) current critically important for spike repolarization in these compartments. Blockade of the current by low doses of 4-aminopyridine or α-dendrotoxin dramatically slows the falling phase of action potentials in axon collaterals and presynaptic boutons. Furthermore, subthreshold depolarization of the soma broadened action potentials in collaterals bearing presynaptic boutons, an effect abolished by blocking Kv1 channels with α-dendrotoxin. These results indicate that action potential-induced synaptic transmission may operate through a mix of analog-digital transmission owing to the properties of Kv1 channels in axon collaterals and presynaptic boutons.

  10. Mechanisms of cardiac pain.

    Science.gov (United States)

    Foreman, Robert D; Garrett, Kennon M; Blair, Robert W

    2015-04-01

    Angina pectoris is cardiac pain that typically is manifested as referred pain to the chest and upper left arm. Atypical pain to describe localization of the perception, generally experienced more by women, is referred to the back, neck, and/or jaw. This article summarizes the neurophysiological and pharmacological mechanisms for referred cardiac pain. Spinal cardiac afferent fibers mediate typical anginal pain via pathways from the spinal cord to the thalamus and ultimately cerebral cortex. Spinal neurotransmission involves substance P, glutamate, and transient receptor potential vanilloid-1 (TRPV1) receptors; release of neurokinins such as nuclear factor kappa b (NF-kb) in the spinal cord can modulate neurotransmission. Vagal cardiac afferent fibers likely mediate atypical anginal pain and contribute to cardiac ischemia without accompanying pain via relays through the nucleus of the solitary tract and the C1-C2 spinal segments. The psychological state of an individual can modulate cardiac nociception via pathways involving the amygdala. Descending pathways originating from nucleus raphe magnus and the pons also can modulate cardiac nociception. Sensory input from other visceral organs can mimic cardiac pain due to convergence of this input with cardiac input onto spinothalamic tract neurons. Reduction of converging nociceptive input from the gallbladder and gastrointestinal tract can diminish cardiac pain. Much work remains to be performed to discern the interactions among complex neural pathways that ultimately produce or do not produce the sensations associated with cardiac pain.

  11. [Abnormal positions of the heart. An analysis on 1039 cases].

    Science.gov (United States)

    Mătăsaru, Silvia; Crupa, Maria; Felea, Doina; Cosmescu, Adriana; Barbacariu, Liliana; Petroaie, Antoneta

    2003-01-01

    The aim was to study the impact of the cardiac malpositions into the group of the 1039 congenital heart diseases registered in the Pediatric Outpatient Department of "Sf. Spiridon" hospital. All patients were investigated noninvasively using clinical examination, electrocardiogram, routine Roentgenogram, two-dimensional and Doppler echocardiography, abdominal echography and, only in two cases, cardiac catheterisation. 23 (2.21%) from 1039 congenital heart diseases registered were cardiac malpositions: dextroposition--3 cases (13.04%), dextrocardia--7 cases (30.43%) and situs inversus--13 cases (56.52%). Most of the children were boys (65.21%), 70% from all cases coming from urban area. Only 3 children had structural cardiac anomalies: two cases with dextrocardia (one with atrial septal defect and one with atrioventricular canal) and one with situs inversus and tetralogy of Fallot, two of them suffering surgical correction. Psychological impact was the main problem of these children, especially during the adolescence, except the two cases with structural cardiac abnormalities who needed following and surgical treatment.

  12. A Rare Stapes Abnormality

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    Hala Kanona

    2015-01-01

    Full Text Available The aim of this study is to increase awareness of rare presentations, diagnostic difficulties alongside management of conductive hearing loss and ossicular abnormalities. We report the case of a 13-year-old female reporting progressive left-sided hearing loss and high resolution computed tomography was initially reported as normal. Exploratory tympanotomy revealed an absent stapedius tendon and lack of connection between the stapes superstructure and footplate. The footplate was fixed. Stapedotomy and stapes prosthesis insertion resulted in closure of the air-bone gap by 50 dB. A review of world literature was performed using MedLine. Middle ear ossicular discontinuity can result in significant conductive hearing loss. This can be managed effectively with surgery to help restore hearing. However, some patients may not be suitable or decline surgical intervention and can be managed safely conservatively.

  13. Examination of the findings on {sup 201}Tl, {sup 123}I-BMIPP dual cardiac SPECT in acute phase of Kawasaki disease

    Energy Technology Data Exchange (ETDEWEB)

    Koga, Yutaka [Matsushita-Kotobuki Electronics Industries Ltd., Ohzu, Ehime (Japan); Ishizuka, Takehiro; Otabe, Hiroyuki; Kori, Takeo; Ota, Toshiko; Suzuki, Kazushige

    1999-02-01

    In 42 cases with acute phase of Kawasaki disease (3-27 days since pathopoiesis), {sup 201}Tl, {sup 123}I-BMIPP dual cardiac SPECT was performed and the reduction of the isotope-uptake was macroscopically assessed. On cardiac SPECT, 28 of 42 cases (67%), and 19 of 30 cases (63%) who were normal on electrocardiogram, echocardiogram and blood CK levels showed abnormal images. In a part of cases showing abnormal cardiac SPECT, coronary arteriography was performed, and constrictive lesions with more than 25% were not observed. In acute phase of Kawasaki disease, the risk of cardiac complication was thought to be low. But these results suggest that there are cardiac complications detectable by {sup 201}Tl, {sup 123}I-BMIPP dual cardiac SPECT. This cardiac lesions were thought to be intramyocardinal microangiitis or abnormal coronary micro circulation cased by myocarditis associating microangiitis. (K.H.)

  14. Examination of the findings on [sup 201]Tl, [sup 123]I-BMIPP dual cardiac SPECT in acute phase of Kawasaki disease

    Energy Technology Data Exchange (ETDEWEB)

    Koga, Yutaka (Matsushita-Kotobuki Electronics Industries Ltd., Ohzu, Ehime (Japan)); Ishizuka, Takehiro; Otabe, Hiroyuki; Kori, Takeo; Ota, Toshiko; Suzuki, Kazushige

    1999-02-01

    In 42 cases with acute phase of Kawasaki disease (3-27 days since pathopoiesis), [sup 201]Tl, [sup 123]I-BMIPP dual cardiac SPECT was performed and the reduction of the isotope-uptake was macroscopically assessed. On cardiac SPECT, 28 of 42 cases (67%), and 19 of 30 cases (63%) who were normal on electrocardiogram, echocardiogram and blood CK levels showed abnormal images. In a part of cases showing abnormal cardiac SPECT, coronary arteriography was performed, and constrictive lesions with more than 25% were not observed. In acute phase of Kawasaki disease, the risk of cardiac complication was thought to be low. But these results suggest that there are cardiac complications detectable by [sup 201]Tl, [sup 123]I-BMIPP dual cardiac SPECT. This cardiac lesions were thought to be intramyocardinal microangiitis or abnormal coronary micro circulation cased by myocarditis associating microangiitis. (K.H.)

  15. Stimulating endogenous cardiac regeneration

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    Amanda eFinan

    2015-09-01

    Full Text Available The healthy adult heart has a low turnover of cardiac myocytes. The renewal capacity, however, is augmented after cardiac injury. Participants in cardiac regeneration include cardiac myocytes themselves, cardiac progenitor cells, and peripheral stem cells, particularly from the bone marrow compartment. Cardiac progenitor cells and bone marrow stem cells are augmented after cardiac injury, migrate to the myocardium, and support regeneration. Depletion studies of these populations have demonstrated their necessary role in cardiac repair. However, the potential of these cells to completely regenerate the heart is limited. Efforts are now being focused on ways to augment these natural pathways to improve cardiac healing, primarily after ischemic injury but in other cardiac pathologies as well. Cell and gene therapy or pharmacological interventions are proposed mechanisms. Cell therapy has demonstrated modest results and has passed into clinical trials. However, the beneficial effects of cell therapy have primarily been their ability to produce paracrine effects on the cardiac tissue and recruit endogenous stem cell populations as opposed to direct cardiac regeneration. Gene therapy efforts have focused on prolonging or reactivating natural signaling pathways. Positive results have been demonstrated to activate the endogenous stem cell populations and are currently being tested in clinical trials. A potential new avenue may be to refine pharmacological treatments that are currently in place in the clinic. Evidence is mounting that drugs such as statins or beta blockers may alter endogenous stem cell activity. Understanding the effects of these drugs on stem cell repair while keeping in mind their primary function may strike a balance in myocardial healing. To maximize endogenous cardiac regeneration,a combination of these approaches couldameliorate the overall repair process to incorporate the participation ofmultiple cell players.

  16. Cardiac dysfunction after aneurysmal subarachnoid hemorrhage : Relationship with outcome

    NARCIS (Netherlands)

    van der Bilt, Ivo; Hasan, Djo; van den Brink, Renee; Cramer, Maarten-Jan; van der Jagt, Mathieu; van Kooten, Fop; Meertens, John; van den Berg, Maarten; Groen, Rob; ten Cate, Folkert; Kamp, Otto; Goette, Marco; Horn, Janneke; Groeneveld, Johan; Vandertop, Peter; Algra, Ale; Visser, Frans; Wilde, Arthur; Rinkel, Gabriel

    2014-01-01

    OBJECTIVE: To assess whether cardiac abnormalities after aneurysmal subarachnoid hemorrhage (aSAH) are associated with delayed cerebral ischemia (DCI) and clinical outcome, independent from known clinical risk factors for these outcomes. METHODS: In a prospective, multicenter cohort study, we perfor

  17. Cystic Fibrosis in a Female Infant with Cardiac, Ocular, and Musculoskeletal Anomalies

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    Azhar Farooqui

    2015-01-01

    Full Text Available Cystic fibrosis (CF remains the most common hereditary disease in the western population. Its concomitant presence with other congenital abnormalities is a rare phenomenon with very little documentation. In this case report we describe a case of cystic fibrosis in a female infant with cardiac, ocular, and musculoskeletal abnormalities. A brief literature review is also provided.

  18. Electrocardiographic and Echocardiographic Abnormalities in Chronic Alcoholics

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    H.D. Attar

    2017-01-01

    Full Text Available Objective: Alcohol is most commonly abused drug worldwide. It has been shown to produce toxic effects in almost every organ system in the body. Many of these medical conditions can be attributed to direct effects of alcohol whereas others are indirect sequelae that may result from nutritional deficiencies or predisposition to trauma. Alcohol consumption has been associated with a variety of cardio vascular disorders this study was thus undertaken to know the Electrocardiographic and Echocardiographic abnormalities in asymptomatic chronic alcoholic patients. Materials and Methods: 50 Patients attending the out-patient clinic & who were admitted in Al Ameen Medical College Hospital and District hospital, Bijapur were selected for the study. It was a prospective study design subjects in age group 20-40, having history of chronic alcoholism as defined, for more than 5 years were evaluated by electrocardiography and echocardiography. Patients with known diabetics, hypertensive and cardiovascular disorders were excluded from the study group. Results: The prevalence of cardiovascular abnormalities in patients of chronic alcoholism is 37% in our study. Most common ECG changes are sinus tachycardia (18%, and Non specific ST-T changes (9%. Most common 2D ECHO changes was increased posterior wall thickness (11% and followed by increased interventricular septum thickness and decreased ejection fraction (<40%. The prevalence of cardio vascular abnormalities are more with increased duration of alcohol consumption and also high in advanced age group. Conclusions: This study confirms that many electrocardiographic as well as echocardiographic changes occur prior to symptomatic cardiac disorders established to be caused by chronic alcohol intake such as alcoholic cardiomyopathy .which probably are early indictors of ongoing effects of alcohol and are reversible during the early stages detected by non invasive investigations like Electrocardiography and

  19. Preoperative cardiac computed tomography for demonstration of congenital cardiac septal defect in adults

    Energy Technology Data Exchange (ETDEWEB)

    Eom, Hye-Joung; Yang, Dong Hyun; Kang, Joon-Won; Lim, Tae-Hwan [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Cardiac Imaging Center, Asan Medical Center, Seoul (Korea, Republic of); Kim, Dae-Hee; Song, Jong-Min; Kang, Duk-Hyun; Song, Jae-Kwan [University of Ulsan College of Medicine, Department of Cardiology and Heart Institute, Cardiac Imaging Center, Asan Medical Center, Seoul (Korea, Republic of); Kim, Joon Bum; Jung, Sung-Ho; Choo, Suk Jung; Chung, Cheol Hyun; Lee, Jae Won [University of Ulsan College of Medicine, Department of Cardiothoracic surgery, Cardiac Imaging Center, Asan Medical Center, Seoul (Korea, Republic of)

    2015-06-01

    We aimed to evaluate the role of preoperative cardiac computed tomography (CT) for adults with congenital cardiac septal defect (CSD). Sixty-five consecutive patients who underwent preoperative CT and surgery for CSD were included. The diagnostic accuracy of CT and the concordance rate of the subtype classification of CSD were evaluated using surgical findings as the reference standard. Sixty-five patients without CSD who underwent cardiac valve surgery were used as a control group. An incremental value of CT over echocardiography was described retrospectively. Sensitivity and specificity of CT for diagnosis of CSD were 95 % and 100 %, respectively. The concordance rate of subtype classification was 91 % in CT and 92 % in echocardiography. The maximum size of the defect measured by CT correlated well with surgical measurement (r = 0.82), and the limit of agreement was -0.9 ± 7.42 mm. In comparison with echocardiography, CT was able to detect combined abnormalities in three cases, and exclusively provided correct subtype classification or clarified suspected abnormal findings found on echocardiography in seven cases. Cardiac CT can accurately demonstrates CSD in preoperative adult patients. CT may have an incremental role in preoperative planning, particularly in those with more complex anatomy. (orig.)

  20. Depth Attenuation Degree Based Visualization for Cardiac Ischemic Electrophysiological Feature Exploration

    Science.gov (United States)

    Liu, Lei; Zuo, Wangmeng; Zhang, Henggui

    2016-01-01

    Although heart researches and acquirement of clinical and experimental data are progressively open to public use, cardiac biophysical functions are still not well understood. Due to the complex and fine structures of the heart, cardiac electrophysiological features of interest may be occluded when there is a necessity to demonstrate cardiac electrophysiological behaviors. To investigate cardiac abnormal electrophysiological features under the pathological condition, in this paper, we implement a human cardiac ischemic model and acquire the electrophysiological data of excitation propagation. A visualization framework is then proposed which integrates a novel depth weighted optic attenuation model into the pathological electrophysiological model. The hidden feature of interest in pathological tissue can be revealed from sophisticated overlapping biophysical information. Experiment results verify the effectiveness of the proposed method for intuitively exploring and inspecting cardiac electrophysiological activities, which is fundamental in analyzing and explaining biophysical mechanisms of cardiac functions for doctors and medical staff. PMID:28004002

  1. Myocardial bioenergetic abnormalities in experimental uremia

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    Chesser AMS

    2016-05-01

    Full Text Available Alistair MS Chesser,1 Steven M Harwood,2 Martin J Raftery,1 Muhammad M Yaqoob1,2 1Department of Nephrology, Barts Health NHS Trust, Royal London Hospital, 2Translational Medicine and Therapeutics, William Harvey Research Institute, John Vane Science Centre, Queen Mary University of London, London, UK Purpose: Cardiac bioenergetics are known to be abnormal in experimental uremia as exemplified by a reduced phosphocreatine (PCr/adenosine triphosphate (ATP ratio. However, the progression of these bioenergetic changes during the development of uremia still requires further study and was therefore investigated at baseline, 4 weeks and 8 weeks after partial nephrectomy (PNx. Methods: A two-stage PNx uremia model in male Wistar rats was used to explore in vivo cardiac and skeletal muscles' bioenergetic changes over time. High-energy phosphate nucleotides were determined by phosphorus-31 nuclear magnetic resonance (31P-NMR and capillary zone electrophoresis. Results: 31P-NMR spectroscopy revealed lower PCr/ATP ratios in PNx hearts compared to sham (SH-operated animals 4 weeks after PNx (median values given ± SD, 0.64±0.16 PNx, 1.13±0.31 SH, P<0.02. However, 8 weeks after PNx, the same ratio was more comparable between the two groups (0.84±0.15 PNx, 1.04±0.44 SH, P= not significant, suggestive of an adaptive mechanism. When 8-week hearts were prestressed with dobutamine, the PCr/ATP ratio was again lower in the PNx group (1.08±0.36 PNx, 1.55±0.38 SH, P<0.02, indicating a reduced energy reserve during the progression of uremic heart disease. 31P-NMR data were confirmed by capillary zone electrophoresis, and the changes in myocardial bioenergetics were replicated in the skeletal muscle. Conclusion: This study provides evidence of the changes that occur in myocardial energetics in experimental uremia and highlights how skeletal muscle bioenergetics mirror those found in the cardiac tissue and so might potentially serve as a practical surrogate tissue

  2. Raf-mediated cardiac hypertrophy in adult Drosophila.

    Science.gov (United States)

    Yu, Lin; Daniels, Joseph; Glaser, Alex E; Wolf, Matthew J

    2013-07-01

    In response to stress and extracellular signals, the heart undergoes a process called cardiac hypertrophy during which cardiomyocytes increase in size. If untreated, cardiac hypertrophy can progress to overt heart failure that causes significant morbidity and mortality. The identification of molecular signals that cause or modify cardiomyopathies is necessary to understand how the normal heart progresses to cardiac hypertrophy and heart failure. Receptor tyrosine kinase (RTK) signaling is essential for normal human cardiac function, and the inhibition of RTKs can cause dilated cardiomyopathies. However, neither investigations of activated RTK signaling pathways nor the characterization of hypertrophic cardiomyopathy in the adult fly heart has been previously described. Therefore, we developed strategies using Drosophila as a model to circumvent some of the complexities associated with mammalian models of cardiovascular disease. Transgenes encoding activated EGFR(A887T), Ras85D(V12) and Ras85D(V12S35), which preferentially signal to Raf, or constitutively active human or fly Raf caused hypertrophic cardiomyopathy as determined by decreased end diastolic lumen dimensions, abnormal cardiomyocyte fiber morphology and increased heart wall thicknesses. There were no changes in cardiomyocyte cell numbers. Additionally, activated Raf also induced an increase in cardiomyocyte ploidy compared with control hearts. However, preventing increases in cardiomyocyte ploidy using fizzy-related (Fzr) RNAi did not rescue Raf-mediated cardiac hypertrophy, suggesting that Raf-mediated polyploidization is not required for cardiac hypertrophy. Similar to mammals, the cardiac-specific expression of RNAi directed against MEK or ERK rescued Raf-mediated cardiac hypertrophy. However, the cardiac-specific expression of activated ERK(D334N), which promotes hyperplasia in non-cardiac tissues, did not cause myocyte hypertrophy. These results suggest that ERK is necessary, but not sufficient, for

  3. Raf-mediated cardiac hypertrophy in adult Drosophila

    Directory of Open Access Journals (Sweden)

    Lin Yu

    2013-07-01

    In response to stress and extracellular signals, the heart undergoes a process called cardiac hypertrophy during which cardiomyocytes increase in size. If untreated, cardiac hypertrophy can progress to overt heart failure that causes significant morbidity and mortality. The identification of molecular signals that cause or modify cardiomyopathies is necessary to understand how the normal heart progresses to cardiac hypertrophy and heart failure. Receptor tyrosine kinase (RTK signaling is essential for normal human cardiac function, and the inhibition of RTKs can cause dilated cardiomyopathies. However, neither investigations of activated RTK signaling pathways nor the characterization of hypertrophic cardiomyopathy in the adult fly heart has been previously described. Therefore, we developed strategies using Drosophila as a model to circumvent some of the complexities associated with mammalian models of cardiovascular disease. Transgenes encoding activated EGFRA887T, Ras85DV12 and Ras85DV12S35, which preferentially signal to Raf, or constitutively active human or fly Raf caused hypertrophic cardiomyopathy as determined by decreased end diastolic lumen dimensions, abnormal cardiomyocyte fiber morphology and increased heart wall thicknesses. There were no changes in cardiomyocyte cell numbers. Additionally, activated Raf also induced an increase in cardiomyocyte ploidy compared with control hearts. However, preventing increases in cardiomyocyte ploidy using fizzy-related (Fzr RNAi did not rescue Raf-mediated cardiac hypertrophy, suggesting that Raf-mediated polyploidization is not required for cardiac hypertrophy. Similar to mammals, the cardiac-specific expression of RNAi directed against MEK or ERK rescued Raf-mediated cardiac hypertrophy. However, the cardiac-specific expression of activated ERKD334N, which promotes hyperplasia in non-cardiac tissues, did not cause myocyte hypertrophy. These results suggest that ERK is necessary, but not sufficient, for Raf

  4. Is it time for cardiac innervation imaging?

    Energy Technology Data Exchange (ETDEWEB)

    Knuuti, J. [Turku Univ., Turku (Finland) Turku PET Center; Sipola, P. [Kuopio Univ., Kuopio (Finland)

    2005-03-01

    The autonomic nervous system plays an important role in the regulation of cardiac function and the regional distribution of cardiac nerve terminals can be visualized using scintigraphic techniques. The most commonly used tracer is iodine-123-metaiodobenzylguanidine (MIBG) but C-11-hydroxyephedrine has also been used with PET. When imaging with MIBG, the ratio of heart-to-mediastinal counts is used as an index of tracer uptake, and regional distribution is also assessed from tomographic images. The rate of clearance of the tracer can also be measured and indicates the function of the adrenergic system. Innervation imaging has been applied in patients with susceptibility to arrythmias, coronary artery disease, hypertrophic and dilated cardiomyopathy and anthracycline induced cardiotoxicity. Abnormal adrenergic innervation or function appear to exist in many pathophysiological conditions indicating that sympathetic neurons are very susceptible to damage. Abnormal findings in innervation imaging also appear to have significant prognostic value especially in patients with cardiomyopathy. Recently, it has also been shown that innervation imaging can monitor drug-induced changes in cardiac adrenergic activity. Although innervation imaging holds great promise for clinical use, the method has not received wider clinical acceptance. Larger randomized studies are required to confirm the value of innervation imaging in various specific indications.

  5. Marketing cardiac CT programs.

    Science.gov (United States)

    Scott, Jason

    2010-01-01

    There are two components of cardiac CT discussed in this article: coronary artery calcium scoring (CACS) and coronary computed tomography angiography (CCTA).The distinctive advantages of each CT examination are outlined. In order to ensure a successful cardiac CT program, it is imperative that imaging facilities market their cardiac CT practices effectively in order to gain a competitive advantage in this valuable market share. If patients receive quality care by competent individuals, they are more likely to recommend the facility's cardiac CT program. Satisfied patients will also be more willing to come back for any further testing.

  6. Communication and abnormal behaviour.

    Science.gov (United States)

    Crown, S

    1979-01-01

    In this paper the similarities between normal and abnormal behaviour are emphasized and selected aspects of communication, normal and aberrant, between persons are explored. Communication in a social system may be verbal or non-verbal: one person's actions cause a response in another person. This response may be cognitive, behavioural or physiological. Communication may be approached through the individual, the social situation or social interaction. Psychoanalysis approaches the individual in terms of the coded communications of psychoneurotic symptoms or psychotic behaviour; the humanist-existential approach is concerned more with emotional expression. Both approaches emphasize the development of individual identity. The interaction between persons and their social background is stressed. Relevant are sociological concepts such as illness behaviour, stigma, labelling, institutionalization and compliance. Two approaches to social interactions are considered: the gamesplaying metaphor, e.g. back pain as a psychosocial manipulation--the 'pain game'; and the 'spiral of reciprocal perspectives' which emphasizes the interactional complexities of social perceptions. Communicatory aspects of psychological treatments are noted: learning a particular metaphor such as 'resolution' of the problem (psychotherapy), learning more 'rewarding' behaviour (learning theory) or learning authenticity or self-actualization (humanist-existential).

  7. Effects of Obesity on Cardiovascular Hemodynamics, Cardiac Morphology, and Ventricular Function.

    Science.gov (United States)

    Alpert, Martin A; Omran, Jad; Bostick, Brian P

    2016-12-01

    Obesity produces a variety of hemodynamic alterations that may cause changes in cardiac morphology which predispose to left and right ventricular dysfunction. Various neurohormonal and metabolic alterations commonly associated with obesity may contribute to these abnormalities of cardiac structure and function. These changes in cardiovascular hemodynamics, cardiac morphology, and ventricular function may, in severely obese patients, predispose to heart failure, even in the absence of other forms of heart disease (obesity cardiomyopathy). In normotensive obese patients, cardiac involvement is commonly characterized by elevated cardiac output, low peripheral vascular resistance, and increased left ventricular (LV) end-diastolic pressure. Sleep-disordered breathing may lead to pulmonary arterial hypertension and, in association with left heart failure, may contribute to elevation of right heart pressures. These alterations, in association with various neurohormonal and metabolic abnormalities, may produce LV hypertrophy; impaired LV diastolic function; and less commonly, LV systolic dysfunction. Many of these alterations are reversible with substantial voluntary weight loss.

  8. Tuberous sclerosis and cardiac tumors: new electrocardiographic finding in an infant.

    Science.gov (United States)

    Aslan, Eyup; Sap, Fatih; Sert, Ahmet; Odabas, Dursun

    2014-10-01

    Cardiac rhabdomyoma, the primary cardiac tumor most often diagnosed in children, is frequently present in patients with tuberous sclerosis. Most pediatric patients with rhabdomyoma are asymptomatic; however, various electrocardiographic abnormalities can be detected, such as Wolff-Parkinson-White syndrome, ectopic atrial tachycardia, and atrioventricular node dysfunction. We describe the case of a 10-month-old infant girl who had tuberous sclerosis and multiple cardiac rhabdomyomas. Her electrocardiographic presentation was notable for dome-shaped T waves and no ST segment in some leads. To our knowledge, this electrocardiographic finding has not been described in patients with tuberous sclerosis and cardiac masses.

  9. Disruption of cardiac cholinergic neurons enhances susceptibility to ventricular arrhythmias

    Science.gov (United States)

    Jungen, Christiane; Scherschel, Katharina; Eickholt, Christian; Kuklik, Pawel; Klatt, Niklas; Bork, Nadja; Salzbrunn, Tim; Alken, Fares; Angendohr, Stephan; Klene, Christiane; Mester, Janos; Klöcker, Nikolaj; Veldkamp, Marieke W.; Schumacher, Udo; Willems, Stephan; Nikolaev, Viacheslav O.; Meyer, Christian

    2017-01-01

    The parasympathetic nervous system plays an important role in the pathophysiology of atrial fibrillation. Catheter ablation, a minimally invasive procedure deactivating abnormal firing cardiac tissue, is increasingly becoming the therapy of choice for atrial fibrillation. This is inevitably associated with the obliteration of cardiac cholinergic neurons. However, the impact on ventricular electrophysiology is unclear. Here we show that cardiac cholinergic neurons modulate ventricular electrophysiology. Mechanical disruption or pharmacological blockade of parasympathetic innervation shortens ventricular refractory periods, increases the incidence of ventricular arrhythmia and decreases ventricular cAMP levels in murine hearts. Immunohistochemistry confirmed ventricular cholinergic innervation, revealing parasympathetic fibres running from the atria to the ventricles parallel to sympathetic fibres. In humans, catheter ablation of atrial fibrillation, which is accompanied by accidental parasympathetic and concomitant sympathetic denervation, raises the burden of premature ventricular complexes. In summary, our results demonstrate an influence of cardiac cholinergic neurons on the regulation of ventricular function and arrhythmogenesis. PMID:28128201

  10. Right ventricular dysfunction after cardiac surgery - diagnostic options

    DEFF Research Database (Denmark)

    Grønlykke, Lars; Ravn, Hanne Berg; Gustafsson, Finn;

    2017-01-01

    Right ventricular (RV) failure after cardiac surgery is associated with an ominous prognosis. The etiology of RV failure is multifaceted and the ability to recognize RV failure early is paramount in order to initiate timely treatment. The present review focuses on different diagnostic modalities......, reproducibility and comparability of the next generation of diagnostic modalities we propose to use simple, but obtainable echocardiographic measurements and ultimately the insertion of a pulmonary artery catheter (PAC) in order to diagnose RV failure after cardiac surgery....... for RV function and discusses the normal versus abnormal findings in RV monitoring after cardiac surgery and the limitations of the applicable diagnostic modalities. There are specific challenges in RV assessment after cardiac surgery due to a loss of longitudinal contraction and a concomitant gain...

  11. Phospholemman: a novel cardiac stress protein.

    Science.gov (United States)

    Cheung, Joseph Y; Zhang, Xue-Qian; Song, Jianliang; Gao, Erhe; Rabinowitz, Joseph E; Chan, Tung O; Wang, Jufang

    2010-08-01

    Phospholemman (PLM), a member of the FXYD family of regulators of ion transport, is a major sarcolemmal substrate for protein kinases A and C in cardiac and skeletal muscle. In the heart, PLM co-localizes and co-immunoprecipitates with Na(+)-K(+)-ATPase, Na(+)/Ca(2+) exchanger, and L-type Ca(2+) channel. Functionally, when phosphorylated at serine(68), PLM stimulates Na(+)-K(+)-ATPase but inhibits Na(+)/Ca(2+) exchanger in cardiac myocytes. In heterologous expression systems, PLM modulates the gating of cardiac L-type Ca(2+) channel. Therefore, PLM occupies a key modulatory role in intracellular Na(+) and Ca(2+) homeostasis and is intimately involved in regulation of excitation-contraction (EC) coupling. Genetic ablation of PLM results in a slight increase in baseline cardiac contractility and prolongation of action potential duration. When hearts are subjected to catecholamine stress, PLM minimizes the risks of arrhythmogenesis by reducing Na(+) overload and simultaneously preserves inotropy by inhibiting Na(+)/Ca(2+) exchanger. In heart failure, both expression and phosphorylation state of PLM are altered and may partly account for abnormalities in EC coupling. The unique role of PLM in regulation of Na(+)-K(+)-ATPase, Na(+)/Ca(2+) exchanger, and potentially L-type Ca(2+) channel in the heart, together with the changes in its expression and phosphorylation in heart failure, make PLM a rational and novel target for development of drugs in our armamentarium against heart failure. Clin Trans Sci 2010; Volume 3: 189-196.

  12. Effect of NIP-142 on potassium channel alpha-subunits Kv1.5, Kv4.2 and Kv4.3, and mouse atrial repolarization.

    Science.gov (United States)

    Tanaka, Hikaru; Namekata, Iyuki; Hamaguchi, Shogo; Kawamura, Taro; Masuda, Hiroyuki; Tanaka, Yoshio; Iida-Tanaka, Naoko; Takahara, Akira

    2010-01-01

    Effects of NIP-142, a benzopyran compound which terminates experimental atrial arrhythmia, on potassium channel alpha-subunits and mouse atrial repolarization were examined. NIP-142 concentration-dependently blocked the outward current through potassium channel alpha subunits Kv1.5, Kv4.2 and Kv4.3 expressed in Xenopus oocytes. In isolated mouse atrial myocardia, NIP-142 prolonged the action potential duration and effective refractory period, and increased the contractile force. These results suggest that NIP-142 blocks the potassium channels underlying the transient and sustained outward currents, which may contribute to its antiarrhythmic activity.

  13. Kv2 Channel Regulation of Action Potential Repolarization and Firing Patterns in Superior Cervical Ganglion Neurons and Hippocampal CA1 Pyramidal Neurons

    OpenAIRE

    Liu, Pin W.; Bean, Bruce P.

    2014-01-01

    Kv2 family “delayed-rectifier” potassium channels are widely expressed in mammalian neurons. Kv2 channels activate relatively slowly and their contribution to action potential repolarization under physiological conditions has been unclear. We explored the function of Kv2 channels using a Kv2-selective blocker, Guangxitoxin-1E (GxTX-1E). Using acutely isolated neurons, mixed voltage-clamp and current-clamp experiments were done at 37°C to study the physiological kinetics of channel gating and ...

  14. Sex-Based Differences in Cardiac Arrhythmias, ICD Utilisation and Cardiac Resynchronisation Therapy.

    Science.gov (United States)

    Ghani, A; Maas, A H E M; Delnoy, P P H M; Ramdat Misier, A R; Ottervanger, J P; Elvan, A

    2011-01-01

    Many important differences in the presentation and clinical course of cardiac arrhythmias are present between men and women that should be accounted for in clinical practice. In this paper, we review published data on gender differences in cardiac excitable properties, supraventricular tachycardias, ventricular tachycardias, sudden cardiac death, and the utilisation of implantable defibrillators and cardiac resynchronisation therapy. Women have a higher heart rate at rest, and a longer QT interval than men. They further have a narrower QRS complex and lower QRS voltages on the 12-lead ECG with more often non-specific repolarisation abnormalities at rest. Supraventricular tachycardias, such as AV nodal reentrant tachycardia, are twice as frequent in women compared with men. Atrial fibrillation, however, has a 1.5-fold higher prevalence in men. The triggers for idiopathic right ventricular outflow tract tachycardia (VT) initiation are gender specific, i.e. hormonal changes play an important role in the occurrence of these VTs in women. There are clear-cut gender differences in acquired and congenital LQTS. Brugada syndrome affects men more commonly and severely than women. Sudden cardiac death is less prevalent in women at all ages and occurs 10 years later in women than in men. This may be related to the later onset of clinically manifest coronary heart disease in women. Among patients who receive ICDs and CRT devices, women appear to be under-represented, while they may benefit even more from these novel therapies.

  15. Systemic abnormalities in liver disease

    Institute of Scientific and Technical Information of China (English)

    Masami Minemura; Kazuto Tajiri; Yukihiro Shimizu

    2009-01-01

    Systemic abnormalities often occur in patients with liver disease. In particular, cardiopulmonary or renal diseases accompanied by advanced liver disease can be serious and may determine the quality of life and prognosis of patients. Therefore, both hepatologists and non-hepatologists should pay attention to such abnormalities in the management of patients with liver diseases.

  16. Abnormal pressure in hydrocarbon environments

    Science.gov (United States)

    Law, B.E.; Spencer, C.W.

    1998-01-01

    Abnormal pressures, pressures above or below hydrostatic pressures, occur on all continents in a wide range of geological conditions. According to a survey of published literature on abnormal pressures, compaction disequilibrium and hydrocarbon generation are the two most commonly cited causes of abnormally high pressure in petroleum provinces. In young (Tertiary) deltaic sequences, compaction disequilibrium is the dominant cause of abnormal pressure. In older (pre-Tertiary) lithified rocks, hydrocarbon generation, aquathermal expansion, and tectonics are most often cited as the causes of abnormal pressure. The association of abnormal pressures with hydrocarbon accumulations is statistically significant. Within abnormally pressured reservoirs, empirical evidence indicates that the bulk of economically recoverable oil and gas occurs in reservoirs with pressure gradients less than 0.75 psi/ft (17.4 kPa/m) and there is very little production potential from reservoirs that exceed 0.85 psi/ft (19.6 kPa/m). Abnormally pressured rocks are also commonly associated with unconventional gas accumulations where the pressuring phase is gas of either a thermal or microbial origin. In underpressured, thermally mature rocks, the affected reservoirs have most often experienced a significant cooling history and probably evolved from an originally overpressured system.

  17. Cardiac Procedures and Surgeries

    Science.gov (United States)

    ... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More Cardiac Procedures and Surgeries Updated:Sep 16,2016 If you've had ... degree of coronary artery disease (CAD) you have. Cardiac Procedures and Surgeries Angioplasty Also known as Percutaneous Coronary Interventions [PCI], ...

  18. [Advances in cardiac pacing].

    Science.gov (United States)

    de Carranza, María-José Sancho-Tello; Fidalgo-Andrés, María Luisa; Ferrer, José Martínez; Mateas, Francisco Ruiz

    2012-01-01

    This article contains a review of the current status of remote monitoring and follow-up involving cardiac pacing devices and of the latest developments in cardiac resynchronization therapy. In addition, the most important articles published in the last year are discussed.

  19. Non-invasive Mapping of Cardiac Arrhythmias.

    Science.gov (United States)

    Shah, Ashok; Hocini, Meleze; Haissaguerre, Michel; Jaïs, Pierre

    2015-08-01

    Since more than 100 years, 12-lead electrocardiography (ECG) is the standard-of-care tool, which involves measuring electrical potentials from limited sites on the body surface to diagnose cardiac disorder, its possible mechanism, and the likely site of origin. Several decades of research has led to the development of a 252-lead ECG and computed tomography (CT) scan-based three-dimensional electro-imaging modality to non-invasively map abnormal cardiac rhythms including fibrillation. These maps provide guidance towards ablative therapy and thereby help advance the management of complex heart rhythm disorders. Here, we describe the clinical experience obtained using non-invasive technique in mapping the electrical disorder and guide the catheter ablation of atrial arrhythmias (premature atrial beat, atrial tachycardia, atrial fibrillation), ventricular arrhythmias (premature ventricular beats), and ventricular pre-excitation (Wolff-Parkinson-White syndrome).

  20. Cardiac sarcoidosis mimicking right ventricular dysplasia.

    Science.gov (United States)

    Shiraishi, Jun; Tatsumi, Tetsuya; Shimoo, Kazutoshi; Katsume, Asako; Mani, Hiroki; Kobara, Miyuki; Shirayama, Takeshi; Azuma, Akihiro; Nakagawa, Masao

    2003-02-01

    A 59-year-old woman with skin sarcoidosis was admitted to hospital for assessment of complete atrioventricular block. Cross-sectional echocardiography showed that the apical free wall of the right ventricle was thin and dyskinetic with dilation of the right ventricle. Thallium-201 myocardial imaging revealed a normal distribution. Both gallium-67 and technetium-99m pyrophosphate scintigraphy revealed no abnormal uptake in the myocardium. Right ventriculography showed chamber dilation and dyskinesis of the apical free wall, whereas left ventriculography showed normokinesis, mimicking right ventricular dysplasia. Cardiac sarcoidosis was diagnosed on examination of an endomyocardial biopsy specimen from the right ventricle. A permanent pacemaker was implanted to manage the complete atrioventricular block. After steroid treatment, electrocardiography showed first-degree atrioventricular block and echocardiography revealed an improvement in the right ventricular chamber dilation. Reports of cardiac sarcoidosis mimicking right ventricular dysplasia are extremely rare and as this case shows, right ventricular involvement may be one of its manifestations.

  1. Biomaterials for cardiac regeneration

    CERN Document Server

    Ruel, Marc

    2015-01-01

    This book offers readers a comprehensive biomaterials-based approach to achieving clinically successful, functionally integrated vasculogenesis and myogenesis in the heart. Coverage is multidisciplinary, including the role of extracellular matrices in cardiac development, whole-heart tissue engineering, imaging the mechanisms and effects of biomaterial-based cardiac regeneration, and autologous bioengineered heart valves. Bringing current knowledge together into a single volume, this book provides a compendium to students and new researchers in the field and constitutes a platform to allow for future developments and collaborative approaches in biomaterials-based regenerative medicine, even beyond cardiac applications. This book also: Provides a valuable overview of the engineering of biomaterials for cardiac regeneration, including coverage of combined biomaterials and stem cells, as well as extracellular matrices Presents readers with multidisciplinary coverage of biomaterials for cardiac repair, including ...

  2. Electroanatomic Correlates of Depolarization Abnormalities in Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy

    NARCIS (Netherlands)

    Tanawuttiwat, Tanyanan; Te Riele, Anneline S J M; Philips, Binu; James, Cynthia A; Murray, Brittney; Tichnell, Crystal; Sawant, Abhishek C; Calkins, Hugh; Tandri, Harikrishna

    2016-01-01

    BACKGROUND: Epsilon waves and other depolarization abnormalities in the right precordial leads are thought to represent delayed activation of the right ventricular outflow tract in arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C). However, no study has directly correlated cardiac e

  3. Computational approaches to understand cardiac electrophysiology and arrhythmias

    Science.gov (United States)

    Roberts, Byron N.; Yang, Pei-Chi; Behrens, Steven B.; Moreno, Jonathan D.

    2012-01-01

    Cardiac rhythms arise from electrical activity generated by precisely timed opening and closing of ion channels in individual cardiac myocytes. These impulses spread throughout the cardiac muscle to manifest as electrical waves in the whole heart. Regularity of electrical waves is critically important since they signal the heart muscle to contract, driving the primary function of the heart to act as a pump and deliver blood to the brain and vital organs. When electrical activity goes awry during a cardiac arrhythmia, the pump does not function, the brain does not receive oxygenated blood, and death ensues. For more than 50 years, mathematically based models of cardiac electrical activity have been used to improve understanding of basic mechanisms of normal and abnormal cardiac electrical function. Computer-based modeling approaches to understand cardiac activity are uniquely helpful because they allow for distillation of complex emergent behaviors into the key contributing components underlying them. Here we review the latest advances and novel concepts in the field as they relate to understanding the complex interplay between electrical, mechanical, structural, and genetic mechanisms during arrhythmia development at the level of ion channels, cells, and tissues. We also discuss the latest computational approaches to guiding arrhythmia therapy. PMID:22886409

  4. A Case of Infantile Cardiac Rhabdomyoma Complicated by Tuberous Sclerosis

    Science.gov (United States)

    Serikawa, Takehiro; Takahashi, Yasuhiro; Kikuchi, Akira; Takakuwa, Koichi; Usuda, Tohei; Hasegawa, Satoshi; Tanaka, Kenichi

    2010-01-01

    We experienced a case with fetal cardiac tumor, which was diagnosed by prenatal ultrasonographic examination, and the diagnosis was confirmed after birth. A pregnancy woman of the 26th week of gestation was referred to our hospital for close examinations of fetal cardiac tumor. Ultrasonographic examinations revealed single homogeneous tumor with the diameter of 14 mm intracardiac space. The tumor was considered to emerge from the ventricular septum and to be occupied in left ventricle. Other cardiac abnormalities were not detected. The fetus was diagnosed to be complicated with the intracardiac tumor, and with the possible rhabdomyoma of heart. The serial ultrasonographic examinations revealed that the fetal cardiac function was normal. The size of the tumor gradually increased, although the fetal cardiac function revealed within normal range. The patient delivered a female infant weighing 2716g with the Apgar score of 9 and 10 at one and 5 minutes after delivery. The infant was confirmed to have cardiac tumors after examination by pediatric cardiologist, and the cardiac function of the infant was diagnosed as normal condition. The computed tomography of the head revealed the intracranial multiple calcification lesions, which indicated the symptoms of tuberous sclerosis.

  5. Incidental cardiac findings on computed tomography imaging of the thorax

    Directory of Open Access Journals (Sweden)

    El-Gendi Hossam

    2010-12-01

    Full Text Available Abstract Background Investigation of pulmonary pathology with computed tomography also allows visualisation of the heart and major vessels. We sought to explore whether clinically relevant cardiac pathology could be identified on computed tomography pulmonary angiograms (CTPA requested for the exclusion of pulmonary embolism (PE. 100 consecutive CT contrast-enhanced pulmonary angiograms carried out for exclusion of PE at a single centre were assessed retrospectively by two cardiologists. Findings Evidence of PE was reported in 5% of scans. Incidental cardiac findings included: aortic wall calcification (54%, coronary calcification (46%, cardiomegaly (41%, atrial dilatation (18%, mitral annulus calcification (15%, right ventricular dilatation (11%, aortic dilatation (8% and right ventricular thrombus (1%. Apart from 3 (3% reports describing cardiomegaly, no other cardiac findings were described in radiologists' reports. Other reported pulmonary abnormalities included: lung nodules (14%, lobar collapse/consolidation (8%, pleural effusion (2%, lobar collapse/consolidation (8%, emphysema (6% and pleural calcification (4%. Conclusions CTPAs requested for the exclusion of PE have a high yield of cardiac abnormalities. Although these abnormalities may not have implications for acute clinical management, they may, nevertheless, be important in long-term care.

  6. Cardiac tumors: echo assessment.

    Science.gov (United States)

    Mankad, Rekha; Herrmann, Joerg

    2016-12-01

    Cardiac tumors are exceedingly rare (0.001-0.03% in most autopsy series). They can be present anywhere within the heart and can be attached to any surface or be embedded in the myocardium or pericardial space. Signs and symptoms are nonspecific and highly variable related to the localization, size and composition of the cardiac mass. Echocardiography, typically performed for another indication, may be the first imaging modality alerting the clinician to the presence of a cardiac mass. Although echocardiography cannot give the histopathology, certain imaging features and adjunctive tools such as contrast imaging may aid in the differential diagnosis as do the adjunctive clinical data and the following principles: (1) thrombus or vegetations are the most likely etiology, (2) cardiac tumors are mostly secondary and (3) primary cardiac tumors are mostly benign. Although the finding of a cardiac mass on echocardiography may generate confusion, a stepwise approach may serve well practically. Herein, we will review such an approach and the role of echocardiography in the assessment of cardiac masses.

  7. Imaging findings of sternal abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Franquet, T. [Dept. of Radiology, Hospital de Sant Pau, Universidad Autonoma de Barcelona (Spain); Gimenez, A. [Dept. of Radiology, Hospital de Sant Pau, Universidad Autonoma de Barcelona (Spain); Alegret, X. [Dept. of Radiology, Hospital de Sant Pau, Universidad Autonoma de Barcelona (Spain); Sanchis, E. [Dept. of Radiology, Hospital de Sant Pau, Universidad Autonoma de Barcelona (Spain); Rivas, A. [Dept. of Radiology, Hospital Vall d`Hebron, Universidad Autonoma de Barcelona (Spain)

    1997-05-01

    Radiographic findings in the sternal abnormalities are often nonspecific, showing appearances from a localized benign lesion to an aggressive lesion as seen with infections and malignant neoplasms. A specific diagnosis of sternal abnormalities can be suggested on the basis of CT and MR characteristics. Familiarity with the presentation and variable appearance of sternal abnormalities may aid the radiologist is suggesting a specific diagnosis. We present among others characteristic radiographic findings of hemangioma, chondrosarcoma, hydatid disease, and SAPHO syndrome. In those cases in which findings are not specific, cross-sectional imaging modalities may help the clinician in their management. (orig.)

  8. System for the diagnosis and monitoring of coronary artery disease, acute coronary syndromes, cardiomyopathy and other cardiac conditions

    Science.gov (United States)

    Schlegel, Todd T. (Inventor); Arenare, Brian (Inventor)

    2008-01-01

    Cardiac electrical data are received from a patient, manipulated to determine various useful aspects of the ECG signal, and displayed and stored in a useful form using a computer. The computer monitor displays various useful information, and in particular graphically displays various permutations of reduced amplitude zones and kurtosis that increase the rapidity and accuracy of cardiac diagnoses. New criteria for reduced amplitude zones are defined that enhance the sensitivity and specificity for detecting cardiac abnormalities.

  9. hERG (KCNH2 or Kv11.1) K+ channels: screening for cardiac arrhythmia risk.

    Science.gov (United States)

    Bowlby, Mark R; Peri, Ravi; Zhang, Howard; Dunlop, John

    2008-11-01

    Testing new compounds for pro-arrhythmic potential has focused in recent years on avoiding activity at the hERG K+ channel, as hERG block is a common feature of many pro-arrhythmic compounds associated with Torsades de Pointes in humans. Blockers of hERG are well known to prolong cardiac action potentials and lead to long QT syndrome, and activators, although rarer, can lead to short QT syndrome. The most reliable assays of hERG utilize stable cell lines, and include ligand binding, Rb+ flux and electrophysiology (both automated and manual). These assays can be followed by measurement of activity at other ion channels contributing to cardiac contractility and detailed action potential/repolarization measurements in cardiac tissue. An integrated risk assessment for pro-arrhythmic potential is ultimately required, as the constellation of ion channel activities and potencies, along with the mechanism/kinetics of ion channel block, may ultimately be the best predictor of cardiac risk in vivo.

  10. Presynaptic Ca2+-activated K+ channels in glutamatergic hippocampal terminals and their role in spike repolarization and regulation of transmitter release.

    Science.gov (United States)

    Hu, H; Shao, L R; Chavoshy, S; Gu, N; Trieb, M; Behrens, R; Laake, P; Pongs, O; Knaus, H G; Ottersen, O P; Storm, J F

    2001-12-15

    Large-conductance Ca(2+)-activated K(+) channels (BK, also called Maxi-K or Slo channels) are widespread in the vertebrate nervous system, but their functional roles in synaptic transmission in the mammalian brain are largely unknown. By combining electrophysiology and immunogold cytochemistry, we demonstrate the existence of functional BK channels in presynaptic terminals in the hippocampus and compare their functional roles in somata and terminals of CA3 pyramidal cells. Double-labeling immunogold analysis with BK channel and glutamate receptor antibodies indicated that BK channels are targeted to the presynaptic membrane facing the synaptic cleft in terminals of Schaffer collaterals in stratum radiatum. Whole-cell, intracellular, and field-potential recordings from CA1 pyramidal cells showed that the presynaptic BK channels are activated by calcium influx and can contribute to repolarization of the presynaptic action potential (AP) and negative feedback control of Ca(2+) influx and transmitter release. This was observed in the presence of 4-aminopyridine (4-AP, 40-100 microm), which broadened the presynaptic compound action potential. In contrast, the presynaptic BK channels did not contribute significantly to regulation of action potentials or transmitter release under basal experimental conditions, i.e., without 4-AP, even at high stimulation frequencies. This is unlike the situation in the parent cell bodies (CA3 pyramidal cells), where BK channels contribute strongly to action potential repolarization. These results indicate that the functional role of BK channels depends on their subcellular localization.

  11. Inflammation and cardiac dysfunction during sepsis, muscular dystrophy, and myocarditis

    Directory of Open Access Journals (Sweden)

    Ying Li

    2013-12-01

    Full Text Available Inflammation plays an important role in cardiac dysfunction under different situations. Acute systemic inflammation occurring in patients with severe burns, trauma, and inflammatory diseases causes cardiac dysfunction, which is one of the leading causes of mortality in these patients. Acute sepsis decreases cardiac contractility and impairs myocardial compliance. Chronic inflammation such as that occurring in Duchenne muscular dystropshy and myocarditis may cause adverse cardiac remodeling including myocyte hypertrophy and death, fibrosis, and altered myocyte function. However, the underlying cellular and molecular mechanisms for inflammatory cardiomyopathy are still controversial probably due to multiple factors involved. Potential mechanisms include the change in circulating blood volume; a direct inhibition of myocyte contractility by cytokines (tumor necrosis factor (TNF-a, interleukin (IL-1b; abnormal nitric oxide and reactive oxygen species (ROS signaling; mitochondrial dysfunction; abnormal excitation-contraction coupling; and reduced calcium sensitivity at the myofibrillar level and blunted b-adrenergic signaling. This review will summarize recent advances in diagnostic technology, mechanisms, and potential therapeutic strategies for inflammation-induced cardiac dysfunction.

  12. Vagal cardiac efferent innervation in F344 rats: Effects of chronic intermittent hypoxia.

    Science.gov (United States)

    Cheng, Zixi Jack

    2017-03-01

    Chronic intermittent hypoxia (CIH), which is a physiological consequence of obstructive sleep apnea, reduces baroreflex control of heart rate (HR). Previously, we showed that the heart rate (HR) response to electrical stimulation of the vagal efferent nerve was significantly increased following CIH in F344 rats. Since vagal cardiac efferent from the nucleus ambiguus (NA) project to cardiac ganglia and regulate HR, we hypothesized that vagal cardiac efferent innervation of cardiac ganglia is reorganized. Young adult F344 rats were exposed either to room air (RA) or to intermittent hypoxia for 35-50days. Fluorescent tracer DiI was injected into the NA to label vagal efferent innervation of cardiac ganglia which had been counterstained by Fluoro-Gold (FG) injections (i.p). Confocal microscopy was used to examine vagal cardiac efferent axons and terminals in cardiac ganglia. NA axons entered cardiac ganglia and innervated principal neurons (PNs) with robust basket endings in both RA control and CIH animals. In addition, the percentage of PNs which were innervated by DiI-labeled fibers in ganglia was similar. In CIH rats, abnormally large swollen cardiac axon segments and disorganized terminals as well as leaky endings were observed. In general, vagal efferent terminal varicosities around PNs appeared larger and the number of varicosities was significantly increased. Interestingly, some cardiac axons had sprouting-like terminal structures in the cardiac ganglia as well as in cardiac muscle, which had not been found in RA control. Finally, CIH increased the size of PNs and reduced the ratio of nucleus to PN somata. Thus, CIH significantly remodeled the structure of vagal cardiac axons and terminals in cardiac ganglia as well as cardiac PNs.

  13. [Drowning versus cardiac ischemia: Cardiac arrest of an 11-year-old boy at a swimming lake].

    Science.gov (United States)

    Födinger, A; Wöss, C; Semsroth, S; Stadlbauer, K H; Wenzel, V

    2015-11-01

    This report describes a case of sudden cardiac arrest and subsequent attempted cardiopulmonary resuscitation of an 11-year-old child on the shores of a swimming lake. Reports of eyewitnesses excluded the obviously suspected diagnosis of a drowning accident. The result of the autopsy was sudden cardiac death due to a congenital coronary anomaly (abnormal left coronary artery, ALCA). Favored by vigorous physical activity, this anomaly can lead to malignant arrhythmias because the ectopic coronary artery with its intramural course through the aortic wall is compressed during every systole. This pathology was not known to the boy or his family; in fact he liked sports but had suffered of a syncope once which was not followed up. Without a strong suspicion it is difficult to diagnose a coronary artery anomaly and it is often missed even in college athletes. Tragically, sudden cardiac arrest may be the first symptom of an undiagnosed abnormal coronary artery. Following syncope or chest pain during exercise with a normal electrocardiogram (ECG) cardiac imaging, such as computed tomography (CT) or angiography should be initiated in order to enable surgical repair of an abnormal coronary artery.

  14. Skin - abnormally dark or light

    Science.gov (United States)

    ... ency/article/003242.htm Skin - abnormally dark or light To use the sharing features on this page, ... the hands. The bronze color can range from light to dark (in fair-skinned people) with the ...

  15. Pregnancy Complications: Umbilical Cord Abnormalities

    Science.gov (United States)

    ... defects. These tests may include a detailed ultrasound, amniocentesis (to check for chromosomal abnormalities) and in some ... the provider may recommend additional tests, such as amniocentesis and a detailed ultrasound, to diagnose or rule ...

  16. Molecular Basis of Cardiac Myxomas

    Directory of Open Access Journals (Sweden)

    Pooja Singhal

    2014-01-01

    Full Text Available Cardiac tumors are rare, and of these, primary cardiac tumors are even rarer. Metastatic cardiac tumors are about 100 times more common than the primary tumors. About 90% of primary cardiac tumors are benign, and of these the most common are cardiac myxomas. Approximately 12% of primary cardiac tumors are completely asymptomatic while others present with one or more signs and symptoms of the classical triad of hemodynamic changes due to intracardiac obstruction, embolism and nonspecific constitutional symptoms. Echocardiography is highly sensitive and specific in detecting cardiac tumors. Other helpful investigations are chest X-rays, magnetic resonance imaging and computerized tomography scan. Surgical excision is the treatment of choice for primary cardiac tumors and is usually associated with a good prognosis. This review article will focus on the general features of benign cardiac tumors with an emphasis on cardiac myxomas and their molecular basis.

  17. Unique cardiac and cerebral anomalies with chondrodysplasia punctata.

    Science.gov (United States)

    Ciske, D J; Waggoner, D J; Dowton, S B

    1998-01-06

    Chondrodysplasia punctata (CDP) is associated with a variety of genetic and nongenetic conditions. We report a girl with CDP, complex congenital cardiac disease, central nervous system (CNS) anomalies, and clinical findings that resemble those of the sibs described by Toriello et al. [1993, Am J Med Genet 47:797-799]. The cardiac defects and CNS abnormalities reported are unique in the context of CDP and may serve to expand the phenotypic spectrum of the unique form of CDP described by Toriello et al. [1993].

  18. Primary gastric teratoma on the cardiac orifice in an adult

    Institute of Scientific and Technical Information of China (English)

    Liu Liu; Wen Zhuang; Zhong Chen; Yong Zhou; Xiao-Ran Huang

    2009-01-01

    Gastric teratoma (GT) is a seldom seen congenital abnormality. GT always occurs in children. The greater curvature and posterior wall of the stomach are the most common sites involving GT. We diagnosed a case of GT located on the inferior wall of the cardiac orifice in a 20-year-old man. To the best of our knowledge, this is the first case of GT located on the wall of the cardiac orifice in an adult in the English literature. We report this unusual case as an addition to this rare disease usually found in children. Computed tomography combined with endoscopic ultrasonography can be selected to diagnose GT.

  19. Cardiac amyloidosis detection with pyrophosphate-99mTc scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Souza, D.S.F.; Ichiki, W.A.; Coura Filho, G.B.; Izaki, M.; Giorgi, M.C.P.; Soares Junior, J; Meneghetti, J.C. [Universidade de Sao Paulo (FM/USP), SP (Brazil). Fac. de Medicina. Instituto do Coracao. Servico de Medicina Nuclear e Imagem Molecular

    2008-07-01

    Full text: Introduction: Amyloidosis is a rare disease, characterized by extracellular deposition of insoluble amyloid fibrils in organs and tissues. It may affect virtually any system, preferably heart, kidneys and liver. The cardiac involvement produces a spectrum of clinical features, usually with progressive dysfunction. Early diagnosis is important for institution of appropriate therapy. Case report: Male patient, 75 years old, with diagnosed congestive heart failure functional class III and Mobitz II second-degree atrial-ventricular block, was hospitalized for implantation of definitive cardiac pacemaker. Patient mentioned history of worsening effort dyspnoea over a one-month period, progressing to minimum effort, orthopnea, paroxysmal nocturnal dyspnoea and paroxysms of dry cough, and swelling of lower limbs. Echocardiography showed diffuse hypertrophy of left ventricle (LV), with systolic dysfunction due to diffuse hypokinesia and hyperrefringent aspect in the septum. It was questioned a cardiac infiltrating process. Cardiac amyloidosis was considered as a diagnostic hypothesis. The patient underwent a pyrophosphate-{sup 99m}Tc scintigraphy, which showed abnormal tracer uptake in the heart projection, with diffuse pattern on the left ventricle walls, compatible with the clinical suspicion cardiac amyloidosis, which was later confirmed by endomyocardial biopsy. Discussion: In this case report, the patient had clinical and other auxiliary examinations, such as electrocardiography and Doppler echocardiography, compatible with cardiac amyloidosis, which led to implementation with pyrophosphate-{sup 99m}Tc scintigraphy and later endomyocardial biopsy. Cardiac amyloidosis occurs in about half the cases of primary amyloidosis (AL) and is rare in secondary amyloidosis (AA). Its clinical presentation is polymorphic and it can be classified into four distinctive types: restrictive cardiomyopathy, systolic dysfunction, postural hypotension and conduction disorders

  20. Cardiac Tumors; Tumeurs cardiaques

    Energy Technology Data Exchange (ETDEWEB)

    Laissy, J.P.; Fernandez, P. [Centre Hospitalier Universitaire Bichat Claude Bernard, Service d' Imagerie, 76 - Rouen (France); Mousseaux, E. [Hopital Europeen Georges Pompidou (HEGP), Service de Radiologie Cardio Vasculaire et Interventionnelle, 75 - Paris (France); Dacher, J.N. [Centre Hospitalier Universitaire Charles Nicolle, 75 - Rouen (France); Crochet, D. [Centre Hospitalier Universitaire, Hopital Laennec, Centre Hemodynamique, Radiologie Thoracique et Vasculaire, 44 - Nantes (France)

    2004-04-01

    Metastases are the most frequent tumors of the heart even though they seldom are recognized. Most primary cardiac tumors are benign. The main role of imaging is to differentiate a cardiac tumor from thrombus and rare pseudo-tumors: tuberculoma, hydatid cyst. Echocardiography is the fist line imaging technique to detect cardiac tumors, but CT and MRl arc useful for further characterization and differential diagnosis. Myxoma of the left atrium is the most frequent benign cardiac tumor. It usually is pedunculated and sometimes calcified. Sarcoma is the most frequent primary malignant tumor and usually presents as a sessile infiltrative tumor. Lymphoma and metastases are usually recognized by the presence of known tumor elsewhere of by characteristic direct contiguous involvement. Diagnosing primary and secondary pericardial tumors often is difficult. Imaging is valuable for diagnosis, characterization, pre-surgical evaluation and follow-up. (author)

  1. Socially differentiated cardiac rehabilitation

    DEFF Research Database (Denmark)

    Meillier, Lucette Kirsten; Nielsen, Kirsten Melgaard; Larsen, Finn Breinholt;

    2012-01-01

    to a standard rehabilitation programme (SRP). If patients were identified as socially vulnerable, they were offered an extended version of the rehabilitation programme (ERP). Excluded patients were offered home visits by a cardiac nurse. Concordance principles were used in the individualised programme elements......%. Patients were equally distributed to the SRP and the ERP. No inequality was found in attendance and adherence among referred patients. Conclusions: It seems possible to overcome unequal referral, attendance, and adherence in cardiac rehabilitation by organisation of systematic screening and social......Aim: The comprehensive cardiac rehabilitation (CR) programme after myocardial infarction (MI) improves quality of life and results in reduced cardiac mortality and recurrence of MI. Hospitals worldwide face problems with low participation rates in rehabilitation programmes. Inequality...

  2. Cardiac arrest - cardiopulmonary resuscitation

    Institute of Scientific and Technical Information of China (English)

    Basri Lenjani; Besnik Elshani; Nehat Baftiu; Kelmend Pallaska; Kadir Hyseni; Njazi Gashi; Nexhbedin Karemani; Ilaz Bunjaku; Taxhidin Zaimi; Arianit Jakupi

    2014-01-01

    Objective:To investigate application of cardiopulmonary resuscitation(CPR) measures within the golden minutes inEurope.Methods:The material was taken from theUniversityClinical Center ofKosovo -EmergencyCentre inPristina, during the two(2) year period(2010-2011).The collected date belong to the patients with cardiac arrest have been recorded in the patients' log book protocol at the emergency clinic.Results:During the2010 to2011 in the emergency center of theCUCK inPristina have been treated a total of269 patients with cardiac arrest, of whom159 or59.1% have been treated in2010, and110 patients or40.9% in2011.Of the269 patients treated in the emergency centre,93 or34.6% have exited lethally in the emergency centre, and176 or 65.4% have been transferred to other clinics.In the total number of patients with cardiac arrest, males have dominated with186 cases, or69.1%.The average age of patients included in the survey was56.7 year oldSD±16.0 years.Of the269 patients with cardiac arrest, defibrillation has been applied for93 or34.6% of patients.In the outpatient settings defibrillation has been applied for3 or3.2% of patients.Patients were defibrillated with application of one to four shocks. Of27 cases with who have survived cardiac arrest, none of them have suffered cardiac arrest at home,3 or11.1% of them have suffered cardiac arrest on the street, and24 or88.9% of them have suffered cardiac arrest in the hospital.5 out of27 patients survived have ended with neurological impairment.Cardiac arrest cases were present during all days of the week, but frequently most reported cases have been onMonday with32.0% of cases, and onFriday with24.5% of cases. Conclusions:All survivors from cardiac arrest have received appropriate medical assistance within10 min from attack, which implies that if cardiac arrest occurs near an institution health care(with an opportunity to provide the emergent health care) the rate of survival is higher.

  3. Cardiac imaging in adults

    Energy Technology Data Exchange (ETDEWEB)

    Jaffe, C.C.

    1987-01-01

    This book approaches adult cardiac disease from the correlative imaging perspective. It includes chest X-rays and angiographs, 2-dimensional echocardiograms with explanatory diagrams for clarity, plus details on digital radiology, nuclear medicine techniques, CT and MRI. It also covers the normal heart, valvular heart disease, myocardial disease, pericardial disease, bacterial endocarditis, aortic aneurysm, cardiac tumors, and congenital heart disease of the adult. It points out those aspects where one imaging technique has significant superiority.

  4. Port Access Cardiac Surgery.

    Science.gov (United States)

    Viganó, Mario; Minzioni, Gaetano; Spreafico, Patrizio; Rinaldi, Mauro; Pasquino, Stefano; Ceriana, Piero; Locatelli, Alessandro

    2000-10-01

    The port-access technique for cardiac surgery was recently developed at Stanford University in California as a less invasive method to perform some cardiac operations. The port-access system has been described in detail elsewhere. It is based on femoral arterial and venous access for cardiopulmonary bypass (CPB) and on the adoption of a specially designed triple-lumen catheter described originally by Peters, and subsequently modified and developed in the definitive configuration called the endoaortic clamp.

  5. Awareness in cardiac anesthesia.

    LENUS (Irish Health Repository)

    Serfontein, Leon

    2010-02-01

    Cardiac surgery represents a sub-group of patients at significantly increased risk of intraoperative awareness. Relatively few recent publications have targeted the topic of awareness in this group. The aim of this review is to identify areas of awareness research that may equally be extrapolated to cardiac anesthesia in the attempt to increase understanding of the nature and significance of this scenario and how to reduce it.

  6. Post cardiac injury syndrome

    DEFF Research Database (Denmark)

    Nielsen, S L; Nielsen, F E

    1991-01-01

    The post-pericardiotomy syndrome is a symptom complex which is similar in many respects to the post-myocardial infarction syndrome and these are summarized under the diagnosis of the Post Cardiac Injury Syndrome (PCIS). This condition, which is observed most frequently after open heart surgery, i...... on the coronary vessels, with cardiac tamponade and chronic pericardial exudate. In the lighter cases, PCIS may be treated with NSAID and, in the more severe cases, with systemic glucocorticoid which has a prompt effect....

  7. Autonomic cardiac innervation

    OpenAIRE

    Hasan, Wohaib

    2013-01-01

    Autonomic cardiac neurons have a common origin in the neural crest but undergo distinct developmental differentiation as they mature toward their adult phenotype. Progenitor cells respond to repulsive cues during migration, followed by differentiation cues from paracrine sources that promote neurochemistry and differentiation. When autonomic axons start to innervate cardiac tissue, neurotrophic factors from vascular tissue are essential for maintenance of neurons before they reach their targe...

  8. Infected cardiac hydatid cyst

    OpenAIRE

    Ceviz, M; Becit, N; Kocak, H.

    2001-01-01

    A 24 year old woman presented with chest pain and palpitation. The presence of a semisolid mass—an echinococcal cyst or tumour—in the left ventricular apex was diagnosed by echocardiography, computed tomography, and magnetic resonance imaging. The infected cyst was seen at surgery. The cyst was removed successfully by using cardiopulmonary bypass with cross clamp.


Keywords: cardiac hydatid cyst; infected cardiac hydatid cyst

  9. Cardiac applications of optogenetics.

    Science.gov (United States)

    Ambrosi, Christina M; Klimas, Aleksandra; Yu, Jinzhu; Entcheva, Emilia

    2014-08-01

    In complex multicellular systems, such as the brain or the heart, the ability to selectively perturb and observe the response of individual components at the cellular level and with millisecond resolution in time, is essential for mechanistic understanding of function. Optogenetics uses genetic encoding of light sensitivity (by the expression of microbial opsins) to provide such capabilities for manipulation, recording, and control by light with cell specificity and high spatiotemporal resolution. As an optical approach, it is inherently scalable for remote and parallel interrogation of biological function at the tissue level; with implantable miniaturized devices, the technique is uniquely suitable for in vivo tracking of function, as illustrated by numerous applications in the brain. Its expansion into the cardiac area has been slow. Here, using examples from published research and original data, we focus on optogenetics applications to cardiac electrophysiology, specifically dealing with the ability to manipulate membrane voltage by light with implications for cardiac pacing, cardioversion, cell communication, and arrhythmia research, in general. We discuss gene and cell delivery methods of inscribing light sensitivity in cardiac tissue, functionality of the light-sensitive ion channels within different types of cardiac cells, utility in probing electrical coupling between different cell types, approaches and design solutions to all-optical electrophysiology by the combination of optogenetic sensors and actuators, and specific challenges in moving towards in vivo cardiac optogenetics.

  10. [Diagnosticum of abnormalities of plant meiotic division].

    Science.gov (United States)

    Shamina, N V

    2006-01-01

    Abnormalities of plant meiotic division leading to abnormal meiotic products are summarized schematically in the paper. Causes of formation of monads, abnormal diads, triads, pentads, polyads, etc. have been observed in meiosis with both successive and simultaneous cytokinesis.

  11. Memetics clarification of abnormal behavior

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: Biological medicine is hard to fully and scientifically explain the etiological factor and pathogenesis of abnormal behaviors; while, researches on philosophy and psychology (including memetics) are beneficial to better understand and explain etiological factor and pathogenesis of abnormal behaviors. At present, the theory of philosophy and psychology is to investigate the entity of abnormal behavior based on the views of memetics.METHODS: Abnormal behavior was researched in this study based on three aspects, including instinctive behavior disorder, poorly social-adapted behavior disorder and mental or body disease associated behavior disorder. Most main viewpoints of memetics were derived from "The Meme Machine", which was written by Susan Blackmore. When questions about abnormal behaviors induced by mental and psychological diseases and conduct disorder of teenagers were discussed, some researching achievements which were summarized by authors previously were added in this study, such as aggressive behaviors, pathologically aggressive behaviors, etc.RESULTS: The abnormal behaviors mainly referred to a part of people's substandard behaviors which were not according with the realistic social environment, culture background and the pathologic behaviors resulted from people's various psychological diseases. According to the theory of "meme", it demonstrated that the relevant behavioral obstacles of various psychological diseases, for example, the unusual behavior of schizophrenia, were caused, because the old meme was destroyed thoroughly but the new meme was unable to establish; psychoneurosis and personality disorder were resulted in hard establishment of meme; the behavioral obstacles which were ill-adapted to society, for example, various additional and homosexual behaviors, were because of the selfish replications and imitations of "additional meme" and "homosexual meme"; various instinct behavioral and congenital intelligent obstacles were not significance

  12. Calmodulin is essential for cardiac IKS channel gating and assembly: impaired function in long-QT mutations

    DEFF Research Database (Denmark)

    Shamgar, Liora; Ma, Lijuan; Schmitt, Nicole;

    2006-01-01

    The slow IKS K+ channel plays a major role in repolarizing the cardiac action potential and consists of the assembly of KCNQ1 and KCNE1 subunits. Mutations in either KCNQ1 or KCNE1 genes produce the long-QT syndrome, a life-threatening ventricular arrhythmia. Here, we show that long-QT mutations...... located in the KCNQ1 C terminus impair calmodulin (CaM) binding, which affects both channel gating and assembly. The mutations produce a voltage-dependent macroscopic inactivation and dramatically alter channel assembly. KCNE1 forms a ternary complex with wild-type KCNQ1 and Ca(2+)-CaM that prevents...... the risk of ventricular arrhythmias. Udgivelsesdato: 2006-Apr-28...

  13. Thyroid abnormality in perimenopausal women with abnormal uterine bleeding

    Directory of Open Access Journals (Sweden)

    Prasanna Byna

    2015-11-01

    Full Text Available Background: AUB is a common but complicated clinical presentation and occurs in 15-20% of women between menarche to menopause and significantly affects the women's health. Women with thyroid dysfunction often have menstrual irregularities, infertility and increased morbidity during pregnancy. The objective of present study is to find the correlation between thyroid disorders and AUB in perimenopausal women attending gynecology OPD. Methods: In the present study, fifty five patients with AUB were included and were evaluated for the cause including thyroid abnormality. Thyroid function tests were done in all patients. Results: Among 55 patients, 12 patients were diagnosed as hypothyroidism and 7 as hyperthyroidism, women with AUB 36 (65.4% were euthyroid. Among 19 women with thyroid abnormality, heavy menstrual bleeding was seen in 8 (42% women, 6 (31.57% had polymenorrhagia, 5 (26.31% had oligomenorrhoea. The frequent menstrual abnormality in women with hypothyroidism (12 women was heavy menstrual bleeding in 5 (41.6% women, 3 (25% had oligomennorhoea, 4 (33.3% had polymenorrhagia. Out of 7 women with hyperthyroidism, 2 (28.57% had oligomenorrhoea, 3 (42.8% had heavy menstrual bleeding, 2 (28.57% had polymenorrhagia. In a total of 55 patients with AUB, 11 (20% had structural abnormalities in uterus and ovaries. 5 (9% had adenomyosis, 3 (5.4% had ovarian cysts, 3 (5.4% had fibroids. Conclusions: It is important to screen all women for thyroid abnormality who are presenting with AUB especially with non-structural causes of AUB. Correction of thyroid abnormalities also relieves AUB. This will avoid unnecessary hormonal treatment and surgery. [Int J Res Med Sci 2015; 3(11.000: 3250-3253

  14. Usefulness of Cardiac Sympathetic Nerve Imaging Using (123)Iodine-Metaiodobenzylguanidine Scintigraphy for Predicting Sudden Cardiac Death in Patients With Heart Failure.

    Science.gov (United States)

    Kasama, Shu; Toyama, Takuji; Kurabayashi, Masahiko

    2016-01-01

    The autonomic nervous system plays an important role in the human heart. Activation of the cardiac sympathetic nervous system is a cardinal pathophysiological abnormality associated with the failing human heart. Myocardial imaging using (123)I-metaiodobenzylguanidine (MIBG), an analog of norepinephrine, can be used to investigate the activity of norepinephrine, the predominant neurotransmitter of the sympathetic nervous system. Many clinical trials have demonstrated that (123)I-MIBG scintigraphic parameters predict cardiac adverse events, especially sudden cardiac death, in patients with heart failure. In this review, we summarize results from published studies that have focused on the use of cardiac sympathetic nerve imaging using (123)I-MIBG scintigraphy for risk stratification of sudden cardiac death in patients with heart failure.

  15. A novel association of biventricular cardiac noncompaction and diabetic embryopathy: case report and review of the literature.

    Science.gov (United States)

    Woo, Jennifer S; Perez-Rosendahl, Mari; Haydel, Dana; Perens, Gregory; Fishbein, Michael C

    2015-01-01

    Diabetic embryopathy refers to a constellation of congenital malformations arising in the setting of poorly controlled maternal diabetes mellitus. Cardiac abnormalities are the most frequently observed findings, with a 5-fold risk over normal pregnancies. Although a diverse spectrum of cardiac defects has been documented, cardiac noncompaction morphology has not been associated with this syndrome. In this report, we describe a novel case of biventricular cardiac noncompaction in a neonate of a diabetic mother. The patient was a late preterm female with right anotia, caudal dysgenesis, multiple cardiac septal and aortic arch defects, and biventricular cardiac noncompaction. Examination of both ventricles demonstrated spongy myocardium with increased myocardial trabeculation greater than 50% left ventricular thickness and greater than 75% right ventricular thickness, with hypoplasia of the bilateral papillary muscles, consistent with noncompaction morphology. Review of the literature highlights the importance of gene expression and epigenomic regulation in cardiac embryogenesis.

  16. Pentoxifylline Attenuates Cardiac Remodeling Induced by Tobacco Smoke Exposure

    Energy Technology Data Exchange (ETDEWEB)

    Minicucci, Marcos; Oliveira, Fernando; Santos, Priscila; Polegato, Bertha; Roscani, Meliza; Fernandes, Ana Angelica; Lustosa, Beatriz; Paiva, Sergio; Zornoff, Leonardo; Azevedo, Paula, E-mail: paulasa@fmb.unesp.br [Faculdade de Medicina de Botucatu, Universidade Estadual Paulista, São Paulo, SP (Brazil)

    2016-05-15

    Tobacco smoke exposure is an important risk factor for cardiac remodeling. Under this condition, inflammation, oxidative stress, energy metabolism abnormalities, apoptosis, and hypertrophy are present. Pentoxifylline has anti‑inflammatory, anti-apoptotic, anti-thrombotic and anti-proliferative properties. The present study tested the hypothesis that pentoxifylline would attenuate cardiac remodeling induced by smoking. Wistar rats were distributed in four groups: Control (C), Pentoxifylline (PX), Tobacco Smoke (TS), and PX-TS. After two months, echocardiography, invasive blood pressure measurement, biochemical, and histological studies were performed. The groups were compared by two-way ANOVA with a significance level of 5%. TS increased left atrium diameter and area, which was attenuated by PX. In the isolated heart study, TS lowered the positive derivate (+dp/dt), and this was attenuated by PX. The antioxidants enzyme superoxide dismutase and glutathione peroxidase were decreased in the TS group; PX recovered these activities. TS increased lactate dehydrogenase (LDH) and decreased 3-hydroxyacyl Coenzyme A dehydrogenases (OH-DHA) and citrate synthase (CS). PX attenuated LDH, 3-OH-DHA and CS alterations in TS-PX group. TS increased IL-10, ICAM-1, and caspase-3. PX did not influence these variables. TS induced cardiac remodeling, associated with increased inflammation, oxidative stress, apoptosis, and changed energy metabolism. PX attenuated cardiac remodeling by reducing oxidative stress and improving cardiac bioenergetics, but did not act upon cardiac cytokines and apoptosis.

  17. Characterisation of peripartum cardiomyopathy by cardiac magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Mouquet, Frederic; Groote, Pascal de; Bouabdallaoui, Nadia; Dagorn, Joel; Lamblin, Nicolas; Bauters, Christophe [Pole de Cardiologie et Maladies Vasculaires, CHRU Lille et Universite Lille 2, Lille Cedex (France); Lions, Christophe; Willoteaux, Serge; Beregi, Jean Paul [Radiologie et Imagerie Cardiovasculaire, CHRU Lille et Universite Lille 2, Lille Cedex (France); Deruelle, Philippe [Gynecologie-Maternite, CHRU Lille et Universite Lille 2, Lille Cedex (France)

    2008-12-15

    Peripartum cardiomyopathy (PPCM) is a rare cause of heart failure. Only half of the patients recover normal cardiac function. We assessed the usefulness of magnetic resonance imaging (MRI) and late enhancement imaging to detect myocardial fibrosis in order to predict cardiac function recovery in patients with peripartum cardiomyopathy. Among a consecutive series of 1,037 patients referred for heart failure treatment or prognostic evaluation between 1999 and 2006, eight women had confirmed PPCM. They all underwent echocardiography and cardiac MRI for assessment of left ventricular anatomy, systolic function and detection of myocardial fibrosis through late enhancement imaging. Mean ({+-} SD) baseline left ventricular ejection fraction (LVEF) was 28 {+-} 4%. After a follow-up of 50 {+-} 9 months, half the patients recovered normal cardiac function (LVEF = 58 {+-} 4%) and four did not (LVEF = 35 {+-} 6%). None of the eight patients exhibited abnormal myocardial late enhancement. No difference in MRI characteristics was observed between the two groups. Patients with PPCM do not exhibit a specific cardiac MRI pattern and particularly no myocardial late enhancement. It suggests that myocardial fibrosis does not play a major role in the limitation of cardiac function recovery after PPCM. (orig.)

  18. Depression and Cardiac Disease: Epidemiology, Mechanisms, and Diagnosis

    Directory of Open Access Journals (Sweden)

    Jeff C. Huffman

    2013-01-01

    Full Text Available In patients with cardiovascular disease (CVD, depression is common, persistent, and associated with worse health-related quality of life, recurrent cardiac events, and mortality. Both physiological and behavioral factors—including endothelial dysfunction, platelet abnormalities, inflammation, autonomic nervous system dysfunction, and reduced engagement in health-promoting activities—may link depression with adverse cardiac outcomes. Because of the potential impact of depression on quality of life and cardiac outcomes, the American Heart Association has recommended routine depression screening of all cardiac patients with the 2- and 9-item Patient Health Questionnaires. However, despite the availability of these easy-to-use screening tools and effective treatments, depression is underrecognized and undertreated in patients with CVD. In this paper, we review the literature on epidemiology, phenomenology, comorbid conditions, and risk factors for depression in cardiac disease. We outline the associations between depression and cardiac outcomes, as well as the mechanisms that may mediate these links. Finally, we discuss the evidence for and against routine depression screening in patients with CVD and make specific recommendations for when and how to assess for depression in this high-risk population.

  19. Effects of Lifestyle Modification Programs on Cardiac Risk Factors

    Science.gov (United States)

    Razavi, Moaven; Fournier, Stephen; Shepard, Donald S.; Ritter, Grant; Strickler, Gail K.; Stason, William B.

    2014-01-01

    Medicare conducted a payment demonstration to evaluate the effectiveness of two intensive lifestyle modification programs in patients with symptomatic coronary artery disease: the Dr. Dean Ornish Program for Reversing Heart Disease (Ornish) and Cardiac Wellness Program of the Benson-Henry Mind Body Institute. This report describes the changes in cardiac risk factors achieved by each program during the active intervention year and subsequent year of follow-up. The demonstration enrolled 580 participants who had had an acute myocardial infarction, had undergone coronary artery bypass graft surgery or percutaneous coronary intervention within 12 months, or had documented stable angina pectoris. Of these, 98% completed the intense 3-month intervention, 71% the 12-month intervention, and 56% an additional follow-up year. Most cardiac risk factors improved significantly during the intense intervention period in both programs. Favorable changes in cardiac risk factors and functional cardiac capacity were maintained or improved further at 12 and 24 months in participants with active follow-up. Multivariable regressions found that risk-factor improvements were positively associated with abnormal baseline values, Ornish program participation for body mass index and systolic blood pressure, and with coronary artery bypass graft surgery. Expressed levels of motivation to lose weight and maintain weight loss were significant independent predictors of sustained weight loss (p = 0.006). Both lifestyle modification programs achieved well-sustained reductions in cardiac risk factors. PMID:25490202

  20. Effects of lifestyle modification programs on cardiac risk factors.

    Directory of Open Access Journals (Sweden)

    Moaven Razavi

    Full Text Available Medicare conducted a payment demonstration to evaluate the effectiveness of two intensive lifestyle modification programs in patients with symptomatic coronary artery disease: the Dr. Dean Ornish Program for Reversing Heart Disease (Ornish and Cardiac Wellness Program of the Benson-Henry Mind Body Institute. This report describes the changes in cardiac risk factors achieved by each program during the active intervention year and subsequent year of follow-up. The demonstration enrolled 580 participants who had had an acute myocardial infarction, had undergone coronary artery bypass graft surgery or percutaneous coronary intervention within 12 months, or had documented stable angina pectoris. Of these, 98% completed the intense 3-month intervention, 71% the 12-month intervention, and 56% an additional follow-up year. Most cardiac risk factors improved significantly during the intense intervention period in both programs. Favorable changes in cardiac risk factors and functional cardiac capacity were maintained or improved further at 12 and 24 months in participants with active follow-up. Multivariable regressions found that risk-factor improvements were positively associated with abnormal baseline values, Ornish program participation for body mass index and systolic blood pressure, and with coronary artery bypass graft surgery. Expressed levels of motivation to lose weight and maintain weight loss were significant independent predictors of sustained weight loss (p = 0.006. Both lifestyle modification programs achieved well-sustained reductions in cardiac risk factors.

  1. [Psychosomatic aspects of cardiac arrhythmias].

    Science.gov (United States)

    Siepmann, Martin; Kirch, Wilhelm

    2010-07-01

    Emotional stress facilitates the occurrence of cardiac arrhythmias including sudden cardiac death. The prevalence of anxiety and depression is increased in cardiac patients as compared to the normal population. The risk of cardiovascular mortality is enhanced in patients suffering from depression. Comorbid anxiety disorders worsen the course of cardiac arrhythmias. Disturbance of neurocardiac regulation with predominance of the sympathetic tone is hypothesized to be causative for this. The emotional reaction to cardiac arrhythmias is differing to a large extent between individuals. Emotional stress may result from coping with treatment of cardiac arrhythmias. Emotional stress and cardiac arrhythmias may influence each other in the sense of a vicious circle. Somatoform cardiac arrhythmias are predominantly of psychogenic origin. Instrumental measures and frequent contacts between physicians and patients may facilitate disease chronification. The present review is dealing with the multifaceted relationships between cardiac arrhythmias and emotional stress. The underlying mechanisms and corresponding treatment modalities are discussed.

  2. Association of cardiac and vascular changes with ambient PM2.5 in diabetic individuals

    Directory of Open Access Journals (Sweden)

    Buse John B

    2010-06-01

    Full Text Available Abstract Background and Objective Exposure to fine airborne particles (PM2.5 has been shown to be responsible for cardiovascular and hematological effects, especially in older people with cardiovascular disease. Some epidemiological studies suggest that individuals with diabetes may be a particularly susceptible population. This study examined effects of short-term exposures to ambient PM2.5 on markers of systemic inflammation, coagulation, autonomic control of heart rate, and repolarization in 22 adults (mean age: 61 years with type 2 diabetes. Methods Each individual was studied for four consecutive days with daily assessments of plasma levels of blood markers. Cardiac rhythm and electrocardiographic parameters were examined at rest and with 24-hour ambulatory ECG monitors. PM2.5 and meteorological data were measured daily on the rooftop of the patient exam site. Data were analyzed with models adjusting for season, weekday, meteorology, and a random intercept. To identify susceptible subgroups, effect modification was analyzed by clinical characteristics associated with insulin resistance as well as with oxidative stress and by medication intake. Results Interleukin (IL-6 and tumor necrosis factor alpha showed a significant increase with a lag of two days (percent change of mean level: 20.2% with 95%-confidence interval [6.4; 34.1] and 13.1% [1.9; 24.4], respectively in association with an increase of 10 μg/m3 in PM2.5. Obese participants as well as individuals with elevated glycosylated hemoglobin, lower adiponectin, higher ferritin or with glutathione S-transferase M1 null genotype showed higher IL-6 effects. Changes in repolarization were found immediately as well as up to four days after exposure in individuals without treatment with a beta-adrenergic receptor blocker. Conclusions Exposure to elevated levels of PM2.5 alters ventricular repolarization and thus may increase myocardial vulnerability to arrhythmias. Exposure to PM2.5 also

  3. Intra-beat Scaling Properties of Cardiac Arrhythmias and Sudden Cardiac Death

    Science.gov (United States)

    Rodríguez, Eduardo; Lerma, Claudia; Echeverría, Juan C.; Alvarez-Ramirez, Jose

    2008-02-01

    We applied detrended fluctuation analysis (DFA) to characterize the intra-beat scaling dynamics of electrocardiographic (ECG) recordings from the PhysioNet Sudden Cardiac Death Holter Database. The main finding of this contribution is that, in such recordings involving different types of arrhythmias; the ECG waveform, besides showing a less-random intra-beat dynamics, becomes more regular during bigeminy, ventricular tachycardia (VT) or even atrial fibrillation (AFIB) and ventricular fibrillation (VF) despite the appearance of erratic traces. Thus, notwithstanding that these cardiac rhythm abnormalities are generally considered as irregular and some of them generated by random impulses or wavefronts, the intra-beat scaling properties suggest that regularity dominates the underlying mechanisms of arrhythmias. Among other explanations, this may result from shorted or restricted -less complex- pathways of conduction of the electrical activity within the ventricles.

  4. Abnormal insulin levels and vertigo.

    Science.gov (United States)

    Proctor, C A

    1981-10-01

    Fifty patients with unexplained vertigo (36) or lightheadedness (14) are evaluated, all of whom had abnormal ENGs and normal audiograms. Five hour insulin glucose tolerance tests were performance on all patients, with insulin levels being obtained fasting and at one-half, one, two, and three hours. The results of this investigation were remarkable. Borderline or abnormal insulin levels were discovered in 82% of patients; 90% were found to have either an abnormal glucose tolerance test or at least borderline insulin levels. The response to treatment in these dizzy patients was also startling, with appropriate low carbohydrate diets improving the patient's symptoms in 90% of cases. It is, therefore, apparent that the earliest identification of carbohydrate imbalance with an insulin glucose tolerance test is extremely important in the work-up of the dizzy patients.

  5. Combined cardiological and neurological abnormalities due to filamin A gene mutation

    Science.gov (United States)

    de Wit, Marie Claire Y.; de Coo, Irenaeus F. M.; Lequin, Maarten H.; Halley, Dicky J. J.; Roos-Hesselink, Jolien W.

    2010-01-01

    Background Cardiac defects can be the presenting symptom in patients with mutations in the X-linked gene FLNA. Dysfunction of this gene is associated with cardiac abnormalities, especially in the left ventricular outflow tract, but can also cause a congenital malformation of the cerebral cortex. We noticed that some patients diagnosed at the neurogenetics clinic had first presented to a cardiologist, suggesting that earlier recognition may be possible if the diagnosis is suspected. Methods and results From the Erasmus MC cerebral malformations database 24 patients were identified with cerebral bilateral periventricular nodular heterotopia (PNH) without other cerebral cortical malformations. In six of these patients, a pathogenic mutation in FLNA was present. In five a cardiac defect was also found in the outflow tract. Four had presented to a cardiologist before the cerebral abnormalities were diagnosed. Conclusions The cardiological phenotype typically consists of aortic or mitral regurgitation, coarctation of the aorta or other left-sided cardiac malformations. Most patients in this category will not have a FLNA mutation, but the presence of neurological complaints, hyperlaxity of the skin or joints and/or a family history with similar cardiac or neurological problems in a possibly X-linked pattern may alert the clinician to the possibility of a FLNA mutation. PMID:20730588

  6. Microwave Treatment for Cardiac Arrhythmias

    Science.gov (United States)

    Hernandez-Moya, Sonia

    2009-01-01

    NASA seeks to transfer the NASA developed microwave ablation technology, designed for the treatment of ventricular tachycardia (irregular heart beat), to industry. After a heart attack, many cells surrounding the resulting scar continue to live but are abnormal electrically; they may conduct impulses unusually slowly or fire when they would typically be silent. These diseased areas might disturb smooth signaling by forming a reentrant circuit in the muscle. The objective of microwave ablation is to heat and kill these diseased cells to restore appropriate electrical activity in the heart. This technology is a method and apparatus that provides for propagating microwave energy into heart tissues to produce a desired temperature profile therein at tissue depths sufficient for thermally ablating arrhythmogenic cardiac tissue while preventing excessive heating of surrounding tissues, organs, and blood. A wide bandwidth double-disk antenna is effective for this purpose over a bandwidth of about six gigahertz. A computer simulation provides initial screening capabilities for an antenna such as antenna, frequency, power level, and power application duration. The simulation also allows optimization of techniques for specific patients or conditions. In comparison with other methods that involve direct-current pulses or radio frequencies below 1 GHz, this method may prove more effective in treating ventricular tachycardia. This is because the present method provides for greater control of the location, cross-sectional area, and depth of a lesion via selection of the location and design of the antenna and the choice of microwave power and frequency.

  7. Cardiac and vascular changes in cirrhosis: Pathogenic mechanisms

    Institute of Scientific and Technical Information of China (English)

    HongQun Liu; Seyed Ali Gaskari; Samuel S Lee

    2006-01-01

    Cardiovascular abnormalities accompany both portal hypertension and cirrhosis. These consist of hyperdynamic circulation, defined as reduced mean arterial pressure and systemic vascular resistance, and increased cardiac output. Despite the baseline increased cardiac output,ventricular inotropic and chronotropic responses to stimuli are blunted, a condition known as cirrhotic cardiomyopathy. Both conditions may play an initiating or aggravating pathogenic role in many of the complications of liver failure or portal hypertension including ascites,variceal bleeding, hepatorenal syndrome and increased postoperative mortality after major surgery or liver transplantation. This review briefly examines the major mechanisms that may underlie these cardiovascular abnormalities, concentrating on nitric oxide, endogenous cannabinoids, central neural activation and adrenergic receptor changes. Future work should address the complex interrelationships between these systems.

  8. Cardiac radiology: centenary review.

    Science.gov (United States)

    de Roos, Albert; Higgins, Charles B

    2014-11-01

    During the past century, cardiac imaging technologies have revolutionized the diagnosis and treatment of acquired and congenital heart disease. Many important contributions to the field of cardiac imaging were initially reported in Radiology. The field developed from the early stages of cardiac imaging, including the use of coronary x-ray angiography and roentgen kymography, to nowadays the widely used echocardiographic, nuclear medicine, cardiac computed tomographic (CT), and magnetic resonance (MR) applications. It is surprising how many of these techniques were not recognized for their potential during their early inception. Some techniques were described in the literature but required many years to enter the clinical arena and presently continue to expand in terms of clinical application. The application of various CT and MR contrast agents for the diagnosis of myocardial ischemia is a case in point, as the utility of contrast agents continues to expand the noninvasive characterization of myocardium. The history of cardiac imaging has included a continuous process of advances in our understanding of the anatomy and physiology of the cardiovascular system, along with advances in imaging technology that continue to the present day.

  9. The role of acute hyperinsulinemia in the development of cardiac arrhythmias.

    Science.gov (United States)

    Drimba, László; Döbrönte, Róbert; Hegedüs, Csaba; Sári, Réka; Di, Yin; Németh, Joseph; Szilvássy, Zoltán; Peitl, Barna

    2013-05-01

    Patients with perturbed metabolic control are more prone to develop cardiac rhythm disturbances. The main purpose of the present preclinical study was to investigate the possible role of euglycemic hyperinsulinemia in development of cardiac arrhythmias. Euglycemic hyperinsulinemia was induced in conscious rabbits equipped with a right ventricular pacemaker electrode catheter by hyperinsulinemic euglycemic glucose clamp (HEGC) applying two different rates of insulin infusion (5 and 10 mIU/kg/min) and variable rate of glucose infusion to maintain euglycemia (5.5 ± 0.5 mmol/l). The effect of hyperinsulinemia on cardiac electrophysiological parameters was continuously monitored by means of 12-lead surface ECG recording. Arrhythmia incidence was determined by means of programmed electrical stimulation (PES). The possible role of adrenergic activation was investigated by determination of plasma catecholamine levels and intravenous administration of a beta adrenergic blocking agent, metoprolol. All of the measurements were performed during the steady-state period of HEGC and subsequent to metoprolol administration. Both 5 and 10 mIU/kg/min insulin infusion prolonged significantly QTend, QTc, and Tpeak-Tend intervals. The incidence of ventricular arrhythmias generated by PES was increased significantly by euglycemic hyperinsulinemia and exhibited linear relationship to plasma levels of insulin. No alteration on plasma catecholamine levels could be observed; however, metoprolol treatment restored the prolonged QTend, QTc, and Tpeak-Tend intervals and significantly reduced the hyperinsulinemia-induced increase of arrhythmia incidence. Euglycemic hyperinsulinemia can exert proarrhythmic effect presumably due to the enhancement of transmural dispersion of repolarization. Metoprolol treatment may be of benefit in hyperinsulinemia associated with increased incidence of cardiac arrhythmias.

  10. Kv2 channel regulation of action potential repolarization and firing patterns in superior cervical ganglion neurons and hippocampal CA1 pyramidal neurons.

    Science.gov (United States)

    Liu, Pin W; Bean, Bruce P

    2014-04-02

    Kv2 family "delayed-rectifier" potassium channels are widely expressed in mammalian neurons. Kv2 channels activate relatively slowly and their contribution to action potential repolarization under physiological conditions has been unclear. We explored the function of Kv2 channels using a Kv2-selective blocker, Guangxitoxin-1E (GxTX-1E). Using acutely isolated neurons, mixed voltage-clamp and current-clamp experiments were done at 37°C to study the physiological kinetics of channel gating and action potentials. In both rat superior cervical ganglion (SCG) neurons and mouse hippocampal CA1 pyramidal neurons, 100 nm GxTX-1E produced near-saturating block of a component of current typically constituting ∼60-80% of the total delayed-rectifier current. GxTX-1E also reduced A-type potassium current (IA), but much more weakly. In SCG neurons, 100 nm GxTX-1E broadened spikes and voltage clamp experiments using action potential waveforms showed that Kv2 channels carry ∼55% of the total outward current during action potential repolarization despite activating relatively late in the spike. In CA1 neurons, 100 nm GxTX-1E broadened spikes evoked from -70 mV, but not -80 mV, likely reflecting a greater role of Kv2 when other potassium channels were partially inactivated at -70 mV. In both CA1 and SCG neurons, inhibition of Kv2 channels produced dramatic depolarization of interspike voltages during repetitive firing. In CA1 neurons and some SCG neurons, this was associated with increased initial firing frequency. In all neurons, inhibition of Kv2 channels depressed maintained firing because neurons entered depolarization block more readily. Therefore, Kv2 channels can either decrease or increase neuronal excitability depending on the time scale of excitation.

  11. Analysis of the endocardium and cardiac jelly in truncal development in the cardiac lethal mutant axolotl Ambystoma mexicanum.

    Science.gov (United States)

    Lemanski, L F; Fitzharris, T P

    1989-05-01

    Recessive mutant gene c in axolotls results in a failure of the heart to function because of abnormal embryonic induction processes. The myocardium in this mutant lacks organized sarcomeric myofibrils. The present study was undertaken to determine if developmental abnormalities were evident in other areas of the heart besides the myocardium. A detailed comparative survey of the structure of developing normal and mutant hearts, including the endocardium, its cellular derivatives, and the extracellular matrix, known as cardiac jelly, showed that in the mutant there are fewer than the normal number of endocardial cells lining the heart lumen, the number of mesenchyme cells is reduced, and the cardiac jelly area is greatly enlarged in the posterior part of the truncus adjacent to the ventricle.

  12. Cardiac MRI-confirmed mesalamine-induced myocarditis.

    Science.gov (United States)

    Baker, William L; Saulsberry, Whitney J; Elliott, Kaitlyn; Parker, Matthew W

    2015-09-04

    A 38-year-old Caucasian man with a medical history significant for inflammatory bowel disease (IBD) and mesalamine use presented to the emergency department with stabbing, pleuritic, substernal chest pain over the previous 2 days. Findings of leucocytosis, elevated cardiac enzymes and inflammatory markers, T-wave or ST-segment abnormalities and left ventricular systolic dysfunction suggested mesalamine-induced myocarditis. However, a cardiac MRI confirmed the diagnosis. Signs and symptoms improved within days of withdrawal of mesalamine, and initiation of corticosteroids and follow-up studies within the next year were unremarkable. Importantly, the diagnosis of mesalamine-induced myocarditis confirmed via cardiac MRI is a step rarely performed in published cases.

  13. Cardiac and systemic haemodynamic complications of liver cirrhosis

    DEFF Research Database (Denmark)

    Henriksen, Jens H; Møller, Søren

    2009-01-01

    by physical and pharmacological strain. Cardiac failure is an important cause of mortality after liver transplantation and stressful procedures as insertions of transjugular intrahepatic portal systemic shunt (TIPS), peritoneal venous shunting, and other types of surgery. Improvement of liver function has...... been shown to reverse the cardiovascular complications. The clinical significance is an important topic for future research. At present, no specific treatment can be recommended, and the cardiac failure in cirrhosis should be treated as in non-cirrhotic patients with sodium restriction, diuretics......Cardiovascular complications of liver cirrhosis include cardiac dysfunction and abnormalities in the central-, splanchnic,- and peripheral circulation. Vasodilatation prevails, but vascular beds with various degrees of reduced and increased haemodynamic resistance are the results of massive...

  14. Optogenetics for in vivo cardiac pacing and resynchronization therapies.

    Science.gov (United States)

    Nussinovitch, Udi; Gepstein, Lior

    2015-07-01

    Abnormalities in the specialized cardiac conduction system may result in slow heart rate or mechanical dyssynchrony. Here we apply optogenetics, widely used to modulate neuronal excitability, for cardiac pacing and resynchronization. We used adeno-associated virus (AAV) 9 to express the Channelrhodopsin-2 (ChR2) transgene at one or more ventricular sites in rats. This allowed optogenetic pacing of the hearts at different beating frequencies with blue-light illumination both in vivo and in isolated perfused hearts. Optical mapping confirmed that the source of the new pacemaker activity was the site of ChR2 transgene delivery. Notably, diffuse illumination of hearts where the ChR2 transgene was delivered to several ventricular sites resulted in electrical synchronization and significant shortening of ventricular activation times. These findings highlight the unique potential of optogenetics for cardiac pacing and resynchronization therapies.

  15. 类风湿关节炎心脏损害临床分析%Clinical analysis of cardiac involvement in patients with rheumatoid arthritis

    Institute of Scientific and Technical Information of China (English)

    冯秀媛; 王永福; 庞春艳; 安燕; 张红伟; 张淑芳; 江华

    2010-01-01

    . 13%, electric axis left side in 8. 70%, branch block in 13.04%, left ventricular hypertrophy in 4. 35%, atrial fibrillation in 4. 35%, premature in 8.70%, early repolarization syndrome in 2. 17% and electric-axis right side in 4. 35% patients by ECG examinations. The serum level of CRP (46. 77 ±5. 87) mg/L was significantly higher in RA patients with cardiac involvement than that in the non-cardiac involvement patientsm (28. 45 ±3. 21) mg/L (P <0.05) ;While the serum level of ESR,RF,IgG,IgA,IgM, PLT showed no statistically significant differences between the two groups (P > 0.05); Within RA patients withcardiac involvement, the serum level of CRP showed no significant difference among different sub-groups , which were classified according to the echocardiography performance (P > 0.05). Conclusions Cardiac involvement occurred frequently in patients with rheumatoid arthritis. The valvular disease, arteriosclerosis, reducing of the wall motion and pericardial effusion are the main manifestations by echocardiography examination; Sinus tachycardia, ST-T changes,branch block and premature beats are the main ECG abnormalities. The serum level of CRP is significantly higher in RA patients with cardiac involvement than that with non-cardiac involvement patients. The higher level of CRP in patients with RA may indicate the cardiac involvement presence.

  16. Analysis of electrolyte abnormalities and the mechanisms leading to arrhythmias in heart failure. A literature review.

    Science.gov (United States)

    Urso, C; Canino, B; Brucculeri, S; Firenze, A; Caimi, G

    2016-01-01

    About 50% of deaths from heart failure (HF) are sudden, presumably referable to arrhythmias. Electrolyte and acid-base abnormalities are a frequent and potentially dangerous complication in HF patients. Their incidence is almost always correlated with the severity of cardiac dysfunction; furthermore leading to arrhythmias, these imbalances are associated with a poor prognosis. The frequency of ventricular ectopic beats and sudden cardiac death correlate with both plasma and whole body levels of potassium, especially in alkalemia. The early recognition of these alterations and the knowledge of the pathophysiological mechanisms are useful for the management of these HF patients.

  17. Acid-base and electrolyte abnormalities in heart failure: pathophysiology and implications.

    Science.gov (United States)

    Urso, Caterina; Brucculeri, Salvatore; Caimi, Gregorio

    2015-07-01

    Electrolyte and acid-base abnormalities are a frequent and potentially dangerous complication in subjects with congestive heart failure. This may be due either to the pathophysiological alterations present in the heart failure state leading to neurohumoral activation (stimulation of the renin-angiotensin-aldosterone system, sympathoadrenergic stimulation), or to the adverse events of therapy with diuretics, cardiac glycosides, and ACE inhibitors. Subjects with heart failure may show hyponatremia, magnesium, and potassium deficiencies; the latter two play a pivotal role in the development of cardiac arrhythmias. The early identification of these alterations and the knowledge of the pathophysiological mechanisms are very useful for the management of these patients.

  18. Inhibition of cardiac Kv1.5 potassium current by the anesthetic midazolam: mode of action

    Directory of Open Access Journals (Sweden)

    Vonderlin N

    2014-11-01

    Full Text Available Nadine Vonderlin,1 Fathima Fischer,1 Edgar Zitron,1,2 Claudia Seyler,1 Daniel Scherer,1 Dierk Thomas,1,2 Hugo A Katus,1,2 Eberhard P Scholz1 1Department of Internal Medicine III, University Hospital Heidelberg, Heidelberg, Germany; 2German Centre for Cardiovascular Research (DZHK, Partner Site Heidelberg/Mannheim, Heidelberg, GermanyAbstract: Midazolam is a short-acting benzodiazepine that is widely used in anesthesia. Despite its widespread clinical use, detailed information about cardiac side effects of midazolam is largely lacking. Using the double-electrode voltage clamp technique, we studied pharmacological effects of midazolam on heterologously expressed Kv1.5 channels underlying atrial repolarizing current IKur. Midazolam dose-dependently inhibited Kv1.5 current, yielding an IC50 of 17 µM in an HEK cell line and an IC50 of 104 µM in Xenopus oocytes. We further showed that midazolam did not affect the half-maximal activation voltage of Kv1.5 channels. However, a small negative shift of the inactivation curve could be observed. Midazolam acted as a typical open-channel inhibitor with rapid onset of block and without frequency dependence of block. Taken together, midazolam is an open channel inhibitor of cardiac Kv1.5 channels. These data add to the current understanding of the pharmacological profile of midazolam.Keywords: anesthetics, potassium channels, pharmacology

  19. Screening for cardiac HERG potassium channel interacting proteins using the yeast two-hybrid technique.

    Science.gov (United States)

    Ma, Qingyan; Yu, Hong; Lin, Jijin; Sun, Yifan; Shen, Xinyuan; Ren, Li

    2014-02-01

    The human ERG protein (HERG or Kv 11.1) encoded by the human ether-a-go-go-related gene (herg) is the pore-forming subunit of the cardiac delayed rectifier potassium current (IKr) responsible for action potential (AP) repolarization. Mutations in HERG lead to long-QT syndrome, a major cause of arrhythmias. Protein-protein interactions are fundamental for ion channel trafficking, membrane localization, and functional modulation. To identify proteins involved in the regulation of the HERG channel, we conducted a yeast two-hybrid screen of a human heart cDNA library using the C-terminus or N-terminus of HERG as bait. Fifteen proteins were identified as HERG amino terminal (HERG-NT)-interacting proteins, including Caveolin-1 (a membrane scaffold protein with multiple interacting partners, including G-proteins, kinases and NOS), the zinc finger protein, FHL2 and PTPN12 (a non-receptor tyrosine phosphatase). Eight HERG carboxylic terminal (HERG-CT)-interacting proteins were also identified, including the NF-κB-interacting protein myotrophin, We have identified multiple potential interacting proteins that may regulate cardiac IKr through cytoskeletal interactions, G-protein modulation, phosphorylation and downstream second messenger and transcription cascades. These findings provide further insight into dynamic modulation of HERG under physiological conditions and arrhythmogenesis.

  20. Electrophysiological predictors of sudden cardiac death on physical exercise test in young athletes

    Science.gov (United States)

    Balykova, L. A.; Kotlyarov, A. A.; Ivyanskiy, S. A.; Shirokova, A. A.; Miheeva, K. A.; Makarov, L. M.

    2017-01-01

    The problem of sudden death of young athletes continues to be actual. Among its reasons, primary electric myocardium diseases along with organic heart troubles (cardiomyopathies, cordites, anomalies of coronary arteries) take an important place. The most frequent variant of channelopathesis long QT syndrome (LQTS). Both inherited and acquired LQTS may be the reason of sudden cardiac death during physical activity and have to be revealed prior to sports admission. LQTS diagnostics in young athletes become problematic due to secondary exercise-related QT prolongation. Physical load test may reveal myocardium electric instability and enhance LQTS diagnostics accuracy without genetic testing. The aim was to study electrophysiological parameters of myocardium repolarization and reveal the signs of electrical instability as predictors of the life-threatening arrhythmias in young athletes during physical exercise test. In conclusion, electrophysiological myocardium parameters during physical exercise test noted to be markers of electrical myocardial instability and in combination with the other Schwartz criteria, was evidenced the inherited or acquired LQTS. QTc prolongation in athletes at the peak of exercise as well as in early recovery period were noted to be additional predictor life-threatening arrhythmias and sudden cardiac death in young athletes

  1. Pediatric cardiac postoperative care

    Directory of Open Access Journals (Sweden)

    Auler Jr. José Otávio Costa

    2002-01-01

    Full Text Available The Heart Institute of the University of São Paulo, Medical School is a referral center for the treatment of congenital heart diseases of neonates and infants. In the recent years, the excellent surgical results obtained in our institution may be in part due to modern anesthetic care and to postoperative care based on well-structured protocols. The purpose of this article is to review unique aspects of neonate cardiovascular physiology, the impact of extracorporeal circulation on postoperative evolution, and the prescription for pharmacological support of acute cardiac dysfunction based on our cardiac unit protocols. The main causes of low cardiac output after surgical correction of heart congenital disease are reviewed, and methods of treatment and support are proposed as derived from the relevant literature and our protocols.

  2. Comprehensive cardiac rehabilitation

    DEFF Research Database (Denmark)

    Kruse, Marie; Hochstrasser, Stefan; Zwisler, Ann-Dorthe O;

    2006-01-01

    OBJECTIVES: The costs of comprehensive cardiac rehabilitation are established and compared to the corresponding costs of usual care. The effect on health-related quality of life is analyzed. METHODS: An unprecedented and very detailed cost assessment was carried out, as no guidelines existed...... for the situation at hand. Due to challenging circumstances, the cost assessment turned out to be ex-post and top-down. RESULTS: Cost per treatment sequence is estimated to be approximately euro 976, whereas the incremental cost (compared with usual care) is approximately euro 682. The cost estimate is uncertain...... and may be as high as euro 1.877. CONCLUSIONS: Comprehensive cardiac rehabilitation is more costly than usual care, and the higher costs are not outweighed by a quality of life gain. Comprehensive cardiac rehabilitation is, therefore, not cost-effective....

  3. Toothache of cardiac origin.

    Science.gov (United States)

    Kreiner, M; Okeson, J P

    1999-01-01

    Pain referred to the orofacial structures can sometimes be a diagnostic challenge for the clinician. In some instances, a patient may complain of tooth pain that is completely unrelated to any dental source. This poses a diagnostic and therapeutic problem for the dentist. Cardiac pain most commonly radiates to the left arm, shoulder, neck, and face. In rare instances, angina pectoris may present as dental pain. When this occurs, an improper diagnosis frequently leads to unnecessary dental treatment or, more significantly, a delay of proper treatment. This delay may result in the patient experiencing an acute myocardial infarction. It is the dentist's responsibility to establish a proper diagnosis so that the treatment will be directed toward the source of pain and not to the site of pain. This article reviews the literature concerning referred pain of cardiac origin and presents a case report of toothache of cardiac origin.

  4. Radionuclide angiocardiography in the clinical evaluation of cardiac malpositions in situs solitus in adults.

    Science.gov (United States)

    Guit, G L; Kroon, H M; Chin, J G; Pauwels, E K; van Voorthuisen, A E

    1986-04-01

    A right-sided position of the heart in the chest in situs solitus is an abnormal feature easily discernible from a plain chest radiograph. This cardiac malposition may be due to cardiac displacement (dextroposition), which is usually a feature of lung disease, or a structural abnormality of the heart (dextrocardia). Because each condition has different clinical pathologic implications, it is important to distinguish them. Chest films, however, often provide no conclusive information. We performed radionuclide angiocardiography (RNA) in six adults with a cardiac malposition in situs solitus. It was found that morphologic data obtained from the serial images may distinguish dextroposition from dextrocardia. In addition, these images permitted us to diagnose congenitally corrected transposition, a cardiac anomaly which occurs with increased frequency in situs solitus with dextrocardia. Quantitative shunt detection performed during this procedure is helpful in the differential diagnosis of dextroposition and able to distinguish uncomplicated dextrocardia from dextrocardia associated with other cardiac abnormalities. RNA therefore is a valuable and easily performed method in the analysis of cardiac malpositions in adults.

  5. The cardiac anxiety questionnaire: cross-validation among cardiac inpatients

    NARCIS (Netherlands)

    Beek, M.H. van; Oude Voshaar, R.C.; Deelen, F.M. van; Balkom, A.J. van; Pop, G.A.; Speckens, A.E.

    2012-01-01

    OBJECTIVE: General anxiety symptoms are common in patients with cardiac disease and considered to have an adverse effect on cardiac prognosis. The role of specific cardiac anxiety, however, is still unknown. The aim of this study is to examine the factor structure, reliability, and validity of the D

  6. THE CARDIAC ANXIETY QUESTIONNAIRE : CROSS-VALIDATION AMONG CARDIAC INPATIENTS

    NARCIS (Netherlands)

    van Beek, M. H. C. T.; Voshaar, R. C. Oude; van Deelen, F. M.; van Balkom, A. J. L. M.; Pop, G.; Speckens, A. E. M.

    2012-01-01

    Objective: General anxiety symptoms are common in patients with cardiac disease and considered to have an adverse effect on cardiac prognosis. The role of specific cardiac anxiety, however, is still unknown. The aim of this study is to examine the factor structure, reliability, and validity of the D

  7. Congenital abnormalities in methylmercury poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Gilani, S.H.

    1975-04-01

    This study was undertaken to determine the teratogenic potential of methylmercury on chick embryogenesis. Methylmercuric chloride was dissolved in sodium bicarbonate (0.2%) and administered to the chick embryos at doses ranging from 0.0009 to 0.010 mg per egg. The injections were made at days 2 and 3 on incubation (Groups A and B). All the embryos including controls were examined on the 7th day of incubation. Methylmercury poisoning was observed to be both embryolethal and teratogenic. Within the two groups, embryolethality was higher in Group A. The following congenital abnormalities were observed: exencephaly, shortened and twisted limbs, microphthalmia, shortened and twisted neck, beak abnormalities, everted viscera, reduced body size and hemorrhage all over the body. Exencephaly and limb abnormalities were very common. No differences in the incidence and types of gross abnormalities within both the groups (A and B) were noted. The incidence of malformations among the controls was low. The results of present investigation show that methylmercury poisoning is both embryolethal and teratogenic to early chick embryogenesis. (auth)

  8. Virtual cardioscopy: interactive endocardial visualization to guide RF cardiac ablation

    Science.gov (United States)

    Holmes, David R., III; Rettmann, Maryam E.; Cameron, Bruce M.; Camp, Jon J.; Robb, Richard A.

    2006-03-01

    Cardiac arrhythmias are a debilitating, potentially life threatening condition involving aberrant electrical activity in the heart which results in abnormal heart rhythm. Virtual cardioscopy can play an important role in minimally invasive treatment of cardiac arrhythmias. Second and third generation image-guidance systems are now available for the treatment of arrhythmias using RF ablation catheters. While these 3D tools provide useful information to the clinician, additional enhancements to the virtual cardioscopy display paradigm are critical for optimal therapy guidance. Based on input from clinical collaborators, several key visualization techniques have been developed to enhance the use of virtual cardioscopy during cardiac ablation procedures. We have identified, designed and incorporated several visual cues important to successful virtual cardioscopy. These features include the use of global reference maps, parametric mapping, and focused navigation and targeting using abnormal electro-physiologic activity. Our virtual cardioscopy system is designed for real-time use during RF cardiac ablation procedures. Several unique visualizations from our virtual cardioscopy system will be presented. Evaluation of the system with phantom and animal studies will be presented. This research is supported by grant EB002834 from the National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health.

  9. Autophagy is essential for cardiac morphogenesis during vertebrate development.

    Science.gov (United States)

    Lee, Eunmyong; Koo, Yeon; Ng, Aylwin; Wei, Yongjie; Luby-Phelps, Kate; Juraszek, Amy; Xavier, Ramnik J; Cleaver, Ondine; Levine, Beth; Amatruda, James F

    2014-04-01

    Genetic analyses indicate that autophagy, an evolutionarily conserved lysosomal degradation pathway, is essential for eukaryotic differentiation and development. However, little is known about whether autophagy contributes to morphogenesis during embryogenesis. To address this question, we examined the role of autophagy in the early development of zebrafish, a model organism for studying vertebrate tissue and organ morphogenesis. Using zebrafish that transgenically express the fluorescent autophagy reporter protein, GFP-LC3, we found that autophagy is active in multiple tissues, including the heart, during the embryonic period. Inhibition of autophagy by morpholino knockdown of essential autophagy genes (including atg5, atg7, and becn1) resulted in defects in morphogenesis, increased numbers of dead cells, abnormal heart structure, and reduced organismal survival. Further analyses of cardiac development in autophagy-deficient zebrafish revealed defects in cardiac looping, abnormal chamber morphology, aberrant valve development, and ectopic expression of critical transcription factors including foxn4, tbx5, and tbx2. Consistent with these results, Atg5-deficient mice displayed abnormal Tbx2 expression and defects in valve development and chamber septation. Thus, autophagy plays an essential, conserved role in cardiac morphogenesis during vertebrate development.

  10. Tomoregulin-1 prevents cardiac hypertrophy after pressure overload in mice by inhibiting TAK1-JNK pathways

    Directory of Open Access Journals (Sweden)

    Dan Bao

    2015-08-01

    Full Text Available Cardiac hypertrophy is associated with many forms of heart disease, and identifying important modifier genes involved in the pathogenesis of cardiac hypertrophy could lead to the development of new therapeutic strategies. Tomoregulin-1 is a growth factor that is primarily involved in embryonic development and adult central nervous system (CNS function, and it is expressed abnormally in a variety of CNS pathologies. Tomoregulin-1 is also expressed in the myocardium. However, the effects of tomoregulin-1 on the heart, particularly on cardiac hypertrophy, remains unknown. The aim of the study is to examine whether and by what mechanism tomoregulin-1 regulates the development of cardiac hypertrophy induced by pressure overload. In this study, we found that tomoregulin-1 was significantly upregulated in two cardiac hypertrophy models: cTnTR92Q transgenic mice and thoracic aorta constriction (TAC-induced cardiac hypertrophy mice. The transgenic overexpression of tomoregulin-1 increased the survival rate, improved the cardiac geometry and functional parameters of echocardiography, and decreased the degree of cardiac hypertrophy of the TAC mice, whereas knockdown of tomoregulin-1 expression resulted in an opposite phenotype and exacerbated phenotypes of cardiac hypertrophy induced by TAC. A possible mechanism by which tomoregulin-1 regulates the development of cardiac hypertrophy in TAC-induced cardiac hypertrophy is through inhibiting TGFβ non-canonical (TAK1-JNK pathways in the myocardium. Tomoregulin-1 plays a protective role in the modulation of adverse cardiac remodeling from pressure overload in mice. Tomoregulin-1 could be a therapeutic target to control the development of cardiac hypertrophy.

  11. Cardiac biomarkers in children with congenital heart disease

    Institute of Scientific and Technical Information of China (English)

    Masaya Sugimoto; Seiko Kuwata; Clara Kurishima; Jeong Hye Kim; Yoich Iwamoto; Hideaki Senzaki

    2015-01-01

    Background: Most congenital heart diseases (CHDs) have specific hemodynamics, including volume and pressure overload, as well as cyanosis and pulmonary hypertension, associated with anatomical abnormalities. Such hemodynamic abnormalities can cause activation of neurohormones, inflammatory cytokines, fibroblasts, and vascular endothelial cells, which in turn contribute to the development of pathologic conditions such as cardiac hypertrophy,fi brosis, and cardiac cell damages and death. Measuring biomarker levels facilitates the prediction of these pathological changes, and provides information about the stress placed on the myocardial cells, the severity of the damage, the responses of neurohumoral factors, and the remodeling of the ventricle. Compared to the ample information on cardiac biomarkers in adult heart diseases, data from children with CHD are still limited. Data sources: We reviewed cardiac biomarkers-specifi cally focusing on troponin as a biomarker of myocardial damage, amino-terminal procollagen type III peptide (PIIIP) as a biomarker of myocardialfi brosis and stromal remodeling, and B-type natriuretic peptide (BNP)/N-terminal proBNP as biomarkers of cardiac load and heart failure, by introducing relevant publications, including our own, on pediatric CHD patients as well as adults. Results: Levels of highly sensitive troponin I are elevated in patients with atrial septal defects (ASDs) and ventricular septal defects (VSDs). PIIIP levels are also elevated in patients with ASD, VSD, pulmonary stenosis, and Tetralogy of Fallot. Measurement of BNP and N-terminal proBNP levels shows good correlation with heart failure score in children. Conclusions: In the treatment of children with CHD requiring delicate care, it is vital to know the specifi c degree of myocardial damage and severity of heart failure. Cardiac biomarkers are useful tools for ascertaining the condition of CHDs with ease and are likely to be useful in determining the appropriate care of

  12. Perioperative management of cardiac disease.

    Science.gov (United States)

    Aresti, N A; Malik, A A; Ihsan, K M; Aftab, S M E; Khan, W S

    2014-01-01

    Pre-existing cardiac disease contributes significantly to morbidity and mortality amongst patients undergoing non cardiac surgery. Patients with pre-existing cardiac disease or with risk factors for it, have as much as a 3.9% risk of suffering a major perioperative cardiac event (Lee et al 1999, Devereaux 2005). Furthermore, the incidence of perioperative myocardial infarction (MI) is increased 10 to 50 fold in patients with previous coronary events (Jassal 2008).

  13. Cardiac evaluation in pediatric patients waiting for liver transplantation

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    Seyed Mohsen Dehghani, Naser Honar, Hamid Amoozegar, Ahad Eshraghian, Mohammad Borzooei, Mohammad Hadi Imanieh, Seyed Ali Malek-Hosseini

    2010-01-01

    Full Text Available Background: Cardiovascular abnormalities are among common complication in patients with cirrhosis waiting for liver transplantation (LT. The aim of the present study was to investigate cardiac abnormalities among pediatric liver transplant candidates.Methods: We prospectively evaluated the pediatric patient aged less than 18 years listed for LT between 2006 and 2008. Besides history taking and physical examination all the patients underwent electrocardiogram, chest radiograph, contrast echocardiography and color Doppler echocardiography, as well as arterial blood gas analyses.Results: Totally 89 patients with mean age of 8.1±4.6 years were included in the study. The most common causes for liver disease were cryptogenic cirrhosis followed by biliary atresia and autoimmune cirrhosis. Clubbing was found in 27 out of 89 patients and was the most common abnormalities in physical examination. In 22 patients (24.7% heart murmur was heard by a pediatric cardiologist. Sixty nine patients (77.5% had normal cardiac findings in chest radiograph. Cardiomegaly was found in 17 (19.1% patients as the most common abnormal finding in chest radiograph. Electrocardiogram showed sinus tachycardia in 16 (18% patients. Eleven patients (12.4% had tricuspid regurgitation as the most common abnormal findings in echocardiography. Thirteen (14.6% patients had positive contrast echocardiography in favor of intrapulmonary shunt.Conclusion: As the leading cause of post transplant death after graft rejection are cardiovascular complications cardiac evaluation should be considered in all pediatric patients before LT to lower morbidity and mortality during and after transplantation.

  14. Cardiac troponin I (CTnI level among children with epileptic seizures

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    Ahmed Anwer Attia Khattab

    2014-09-01

    Conclusion: Cardiac troponin I is a perfect tool for early detection of cases with myocardial dysfunction in epileptic patients – cardiac troponin I is significantly increased in children with epilepsy especially the complicated epilepsy. Cardiac injury in epileptic children is more common in patients with early onset epilepsy, positive prenatal problem, idiopathic epilepsy, abnormal imaging and EEG – elevated TnI levels may be of value in assessing the severity and eventual outcome and mortality risk of the disease in children with epilepsy.

  15. Data analysis in cardiac arrhythmias.

    Science.gov (United States)

    Rodrigo, Miguel; Pedrón-Torecilla, Jorge; Hernández, Ismael; Liberos, Alejandro; Climent, Andreu M; Guillem, María S

    2015-01-01

    Cardiac arrhythmias are an increasingly present in developed countries and represent a major health and economic burden. The occurrence of cardiac arrhythmias is closely linked to the electrical function of the heart. Consequently, the analysis of the electrical signal generated by the heart tissue, either recorded invasively or noninvasively, provides valuable information for the study of cardiac arrhythmias. In this chapter, novel cardiac signal analysis techniques that allow the study and diagnosis of cardiac arrhythmias are described, with emphasis on cardiac mapping which allows for spatiotemporal analysis of cardiac signals.Cardiac mapping can serve as a diagnostic tool by recording cardiac signals either in close contact to the heart tissue or noninvasively from the body surface, and allows the identification of cardiac sites responsible of the development or maintenance of arrhythmias. Cardiac mapping can also be used for research in cardiac arrhythmias in order to understand their mechanisms. For this purpose, both synthetic signals generated by computer simulations and animal experimental models allow for more controlled physiological conditions and complete access to the organ.

  16. Biosynthesis of cardiac natriuretic peptides

    DEFF Research Database (Denmark)

    Goetze, Jens Peter

    2010-01-01

    Cardiac-derived peptide hormones were identified more than 25 years ago. An astonishing amount of clinical studies have established cardiac natriuretic peptides and their molecular precursors as useful markers of heart disease. In contrast to the clinical applications, the biogenesis of cardiac...

  17. Cardiac troponins and high-sensitivity cardiac troponin assays.

    Science.gov (United States)

    Conrad, Michael J; Jarolim, Petr

    2014-03-01

    Measurement of circulating cardiac troponins I and T has become integral to the diagnosis of myocardial infarction. This article discusses the structure and function of the troponin complex and the release of cardiac troponin molecules from the injured cardiomyocyte into the circulation. An overview of current cardiac troponin assays and their classification according to sensitivity is presented. The diagnostic criteria, role, and usefulness of cardiac troponin for myocardial infarction are discussed. In addition, several examples are given of the usefulness of high-sensitivity cardiac troponin assays for short-term and long-term prediction of adverse events.

  18. High prevalence of cardiac involvement in patients with myotonic dystrophy type 1

    DEFF Research Database (Denmark)

    Petri, Helle; Witting, Nanna; Ersbøll, Mads Kristian;

    2014-01-01

    .02). CONCLUSION: The cardiac phenotype of DM1 includes a high prevalence of conduction disorders, arrhythmias and risk factors of SCD. Systematic cardiac screening with ECG, Holter-monitoring and echocardiography is needed in order to make a proper characterization of cardiac involvement in DM1....... of controls. Thus, the optimal strategy for assessing cardiac involvement in DM1 is unclear. METHOD: In this large single-centre study, we evaluated 129 unselected DM1 patients (49.6% men), mean (SD) age 44 (14.7) years with family history, physical examination, electrocardiogram (ECG), echocardiography......, Holter-monitoring and muscle strength testing. RESULTS: Cardiac involvement was found in 71 patients (55%) and included: 1) Conduction abnormalities: atrio-ventricular block grade I (AVB grade I) (23.6%), AVB grade II (5.6%), right/left bundle branch block (5.5/3.2%) and prolonged QTc (7.2%); 2...

  19. Prolonged QTc interval and risk of sudden cardiac death in a population of older adults

    DEFF Research Database (Denmark)

    Straus, Sabine M J M; Kors, Jan A; De Bruin, Marie L;

    2006-01-01

    OBJECTIVES: This study sought to investigate whether prolongation of the heart rate-corrected QT (QTc) interval is a risk factor for sudden cardiac death in the general population. BACKGROUND: In developed countries, sudden cardiac death is a major cause of cardiovascular mortality. Prolongation...... of the QTc interval has been associated with ventricular arrhythmias, but in most population-based studies no consistent association was found between QTc prolongation and total or cardiovascular mortality. Only very few of these studies specifically addressed sudden cardiac death. METHODS: This study......). The association between a prolonged QTc interval and sudden cardiac death was estimated using Cox proportional hazards analysis. RESULTS: During an average follow-up period of 6.7 years (standard deviation, 2.3 years) 125 patients died of sudden cardiac death. An abnormally prolonged QTc interval (>450 ms in men...

  20. Calcitriol attenuates cardiac remodeling and dysfunction in a murine model of polycystic ovary syndrome.

    Science.gov (United States)

    Gao, Ling; Cao, Jia-Tian; Liang, Yan; Zhao, Yi-Chao; Lin, Xian-Hua; Li, Xiao-Cui; Tan, Ya-Jing; Li, Jing-Yi; Zhou, Cheng-Liang; Xu, Hai-Yan; Sheng, Jian-Zhong; Huang, He-Feng

    2016-05-01

    Polycystic ovary syndrome (PCOS) is a complex reproductive and metabolic disorder affecting 10 % of reproductive-aged women, and is well associated with an increased prevalence of cardiovascular risk factors. However, there are few data concerning the direct association of PCOS with cardiac pathologies. The present study aims to investigate the changes in cardiac structure, function, and cardiomyocyte survival in a PCOS model, and explore the possible effect of calcitriol administration on these changes. PCOS was induced in C57BL/6J female mice by chronic dihydrotestosterone administration, as evidenced by irregular estrous cycles, obesity and dyslipidemia. PCOS mice progressively developed cardiac abnormalities including cardiac hypertrophy, interstitial fibrosis, myocardial apoptosis, and cardiac dysfunction. Conversely, concomitant administration of calcitriol significantly attenuated cardiac remodeling and cardiomyocyte apoptosis, and improved cardiac function. Molecular analysis revealed that the beneficial effect of calcitriol was associated with normalized autophagy function by increasing phosphorylation levels of AMP-activated protein kinase and inhibiting phosphorylation levels of mammalian target of rapamycin complex. Our findings provide the first evidence for the presence of cardiac remodeling in a PCOS model, and vitamin D supplementation may be a potential therapeutic strategy for the prevention and treatment of PCOS-related cardiac remodeling.

  1. Herbal Supplement Ameliorates Cardiac Hypertrophy in Rats with CCl4-Induced Liver Cirrhosis

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    Ping-Chun Li

    2012-01-01

    Full Text Available We used the carbon tetrachloride (CCl4 induced liver cirrhosis model to test the molecular mechanism of action involved in cirrhosis-associated cardiac hypertrophy and the effectiveness of Ocimum gratissimum extract (OGE and silymarin against cardiac hypertrophy. We treated male wistar rats with CCl4 and either OGE (0.02 g/kg B.W. or 0.04 g/kg B.W. or silymarin (0.2 g/kg B.W.. Cardiac eccentric hypertrophy was induced by CCl4 along with cirrhosis and increased expression of cardiac hypertrophy related genes NFAT, TAGA4, and NBP, and the interleukin-6 (IL-6 signaling pathway related genes MEK5, ERK5, JAK, and STAT3. OGE or silymarin co-treatment attenuated CCl4-induced cardiac abnormalities, and lowered expression of genes which were elevated by this hepatotoxin. Our results suggest that the IL-6 signaling pathway may be related to CCl4-induced cardiac hypertrophy. OGE and silymarin were able to lower liver fibrosis, which reduces the chance of cardiac hypertrophy perhaps by lowering the expressions of IL-6 signaling pathway related genes. We conclude that treatment of cirrhosis using herbal supplements is a viable option for protecting cardiac tissues against cirrhosis-related cardiac hypertrophy.

  2. Cardiac Risk Assessment

    Science.gov (United States)

    ... Risk Assessment Related tests: Lipid Profile , VLDL Cholesterol , hs-CRP , Lp(a) Overview | Common Questions | Related Pages What ... cardiac risk include: High-sensitivity C-reactive protein (hs-CRP) : Studies have shown that measuring CRP with a ...

  3. The cardiac malpositions.

    Science.gov (United States)

    Perloff, Joseph K

    2011-11-01

    Dextrocardia was known in the 17th century and was 1 of the first congenital malformations of the heart to be recognized. Fifty years elapsed before Matthew Baillie published his account of complete transposition in a human of the thoracic and abdominal viscera to the opposite side from what is natural. In 1858, Thomas Peacock stated that "the heart may be congenitally misplaced in various ways, occupying either an unusual position within the thorax, or being situated external to that cavity." In 1915, Maude Abbott described ectopia cordis, and Richard Paltauf's remarkable illustrations distinguished the various types of dextrocardia. In 1928, the first useful classification of the cardiac malpositions was proposed, and in 1966, Elliott et al's radiologic classification set the stage for clinical recognition. The first section of this review deals with the 3 basic cardiac malpositions in the presence of bilateral asymmetry. The second section deals with cardiac malpositions in the presence of bilateral left-sidedness or right-sidedness. Previous publications on cardiac malpositions are replete with an arcane vocabulary that confounds rather than clarifies. Even if the terms themselves are understood, inherent complexity weighs against clarity. This review was designed as a guided tour of an unfamiliar subject.

  4. Minimally invasive per-catheter occlusion and dilation procedures for congenital cardiovascular abnormalities in dogs.

    Science.gov (United States)

    Tobias, Anthony H; Stauthammer, Christopher D

    2010-07-01

    With ever-increasing sophistication of veterinary cardiology, minimally invasive per-catheter occlusion and dilation procedures for the treatment of various congenital cardiovascular abnormalities in dogs have become not only available, but mainstream. Much new information about minimally invasive per-catheter patent ductus arteriosus occlusion has been published and presented during the past few years. Consequently, patent ductus arteriosus occlusion is the primary focus of this article. Occlusion of other less common congenital cardiac defects is also briefly reviewed. Balloon dilation of pulmonic stenosis, as well as other congenital obstructive cardiovascular abnormalities is discussed in the latter part of the article.

  5. Nail abnormalities in rheumatoid arthritis.

    Science.gov (United States)

    Michel, C; Cribier, B; Sibilia, J; Kuntz, J L; Grosshans, E

    1997-12-01

    Many nail abnormalities have traditionally been described in association with rheumatoid arthritis (RA), but their specificity has never been assessed in a controlled study. Our purpose was to evaluate the frequency and the specificity of nail changes associated with RA in a case-controlled study including 50 patients suffering from RA and 50 controls. For each patient, a general skin examination was performed and the 20 nails were examined. The nail features were noted and classified. A chi 2 test or a Fisher test was used to compare the two groups. The only nail abnormalities significantly associated with RA were longitudinal ridging on nine or 10 finger nails (29 patients in the RA group vs. three in the controls, chi 2: P nail (24 patients vs. 10, chi 2: P nail changes were noticed but were not frequent enough to be significant. The presence of longitudinal ridging on the finger nails was significantly associated with RA.

  6. Neuroendocrine abnormalities in Parkinson's disease.

    Science.gov (United States)

    De Pablo-Fernández, Eduardo; Breen, David P; Bouloux, Pierre M; Barker, Roger A; Foltynie, Thomas; Warner, Thomas T

    2017-02-01

    Neuroendocrine abnormalities are common in Parkinson's disease (PD) and include disruption of melatonin secretion, disturbances of glucose, insulin resistance and bone metabolism, and body weight changes. They have been associated with multiple non-motor symptoms in PD and have important clinical consequences, including therapeutics. Some of the underlying mechanisms have been implicated in the pathogenesis of PD and represent promising targets for the development of disease biomarkers and neuroprotective therapies. In this systems-based review, we describe clinically relevant neuroendocrine abnormalities in Parkinson's disease to highlight their role in overall phenotype. We discuss pathophysiological mechanisms, clinical implications, and pharmacological and non-pharmacological interventions based on the current evidence. We also review recent advances in the field, focusing on the potential targets for development of neuroprotective drugs in Parkinson's disease and suggest future areas for research.

  7. Radiological appearances of sinonasal abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    El-Beltagi, A.H.; Sobeih, A.A.; Valvoda, M.; Dahniya, M.H.; Badr, S.S

    2002-08-01

    The aim of this pictorial review is to present a variety of abnormalities of the sinonasal cavities to emphasize the diversity of lesions occurring in this region. These include congenital, neoplastic and granulomatous disorders and some allergic and inflammatory lesions with uncommon radiological appearances, as well as expanding lesions of the facial bones or of dental origin with secondary involvement of the related sinus(es). El-Beltagi, A.H. et al. (2002). Clinical Radiology 57, 702-718.

  8. Computed tomography of thymic abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Schnyder, P.; Candardjis, G.

    1987-05-01

    Computed tomographic examinations of 38 patients with surgically and histologically proven diagnosis were reviewed. Twenty subjects (52%) had an invasive thymoma and 16% an hyperplastic thymus. Myasthenia gravis was present in 6 cases (16%) of thymic abnormalities, four (10,5%) with invasive thymoma and two (5%) with thymic hyperplasia. Graves' disease was also present in one case of thymic hyperplasia. We emphasize the contribution of CT to the diagnosis and the prognosis.

  9. Persistent abnormal coronary flow reserve in association with abnormal glucose metabolism affects prognosis in acute myocardial infarction

    DEFF Research Database (Denmark)

    Løgstrup, Brian B; Høfsten, Dan E; Christophersen, Thomas B

    2011-01-01

    Objectives: To evaluate changes in coronary flow reserve (CFR) over time after acute myocardial infarction (AMI) in relation to left ventricular (LV) function and glucometabolic state and prognostic implication of abnormal CFR. Methods: 154 patients with first time AMI had a comprehensive...... baseline CFR (P = 0.004), S' (P = 0.045) and abnormal glucose metabolism (P = 0.001) were predictors of a decreased CFR at 3 months of follow-up. In multivariate analyses abnormal glucose metabolism (OR: 5.3; 95%CI: 1.9-14.4; P = 0.001) remained a predictor of decreased CFR at follow-up, furthermore...... baseline CFR (OR: 0.5; 95%CI: 0.25-0.94; P = 0.032) and S' (OR: 0.67; 95% CI: 0.47-0.94; P = 0.021) was predictors of decreased CFR. Finally, CFR was associated with a lower risk of cardiac events in patients with normal glucose metabolism (HR: 0.64; 95% CI: 0.22-1.9; P = 0.42) than in patients...

  10. Basal hyperaemia is the primary abnormality of perfusion in Takotsubo cardiomyopathy

    DEFF Research Database (Denmark)

    Christensen, Thomas Emil; Ahtarovski, Kiril Aleksov; Bang, Lia Evi;

    2015-01-01

    hyperperfusion. Our aim was to examine abnormalities of perfusion in TTC, and we hypothesized that basal hyperperfusion is the primary perfusion abnormality in the acute state. METHOD AND RESULTS: Twenty-five patients were diagnosed with TTC due to (i) acute onset of symptoms, (ii) typical apical ballooning......, (iii) absence of significant coronary disease, and (iv) complete remission on 4-month follow-up. The patients underwent coronary angiography (CAG), echocardiography, cardiac magnetic resonance imaging (CMR), and (13)NH3/(82)Rb positron emission tomography (PET) in the acute state and-except CAG......-on follow-up. Patients initially had severe heart failure, mid/apical oedema but no infarction, and a rise in cardiac biomarkers. On initial perfusion PET imaging, eight patients appeared to have normal, whereas 17 patients had impaired LV perfusion. In the latter, flow in the basal region was increased...

  11. Clinical experiences of delayed contrast enhancement with cardiac computed tomography: case series

    Directory of Open Access Journals (Sweden)

    Sidhu Manavjot S

    2013-01-01

    Full Text Available Abstract Background Myocardial delayed enhancement (MDE by gadolinium-enhanced cardiac MRI is well established for myocardial scar assessment in ischemic and non-ischemic heart disease. The role of MDE by cardiac CT (CT-MDE is not yet defined. Findings We reviewed all clinical cases of CT-MDE at a tertiary referral center to present the cases as a case series. All clinical cardiac CT exams which utilized CT-MDE imaging between January 1, 2005 and October 1, 2010 were collected as a series and their findings were also compared with available myocardial imaging to assess for myocardial abnormalities, including echocardiography (wall motion, morphology, cardiac MRI (delayed enhancement, morphology, SPECT MPI (perfusion defects. 5,860 clinical cardiac CT exams were performed during the study period. CT-MDE was obtained in 18 patients and was reported to be present in 9 patients. The indications for CT-MDE included ischemic and non-ischemic heart diseases. In segments positive for CT-MDE, there was excellent agreement of CT with other modalities: echocardiography (n=8 demonstrated abnormal morphology and wall motion (k=1.0 and k=0.82 respectively; prior MRI (n=2 demonstrated abnormal delayed enhancement (MR-MDE (k=1.0; SPECT MPI (n=1 demonstrated fixed perfusion defects (k=1.0. In the subset of patients without CT-MDE, no abnormal segments were identified by echocardiography (n=8, MRI (n=1 and nuclear MPI (n=0. Conclusions CT-MDE was performed in rare clinical situations. The indications included both ischemic and non-ischemic heart disease and there was an excellent agreement between CT-MDE and abnormal myocardium by echocardiography, cardiac MRI, and nuclear MPI.

  12. Meiotic abnormalities in infertile males.

    Science.gov (United States)

    Egozcue, J; Sarrate, Z; Codina-Pascual, M; Egozcue, S; Oliver-Bonet, M; Blanco, J; Navarro, J; Benet, J; Vidal, F

    2005-01-01

    Meiotic anomalies, as reviewed here, are synaptic chromosome abnormalities, limited to germ cells that cannot be detected through the study of the karyotype. Although the importance of synaptic errors has been underestimated for many years, their presence is related to many cases of human male infertility. Synaptic anomalies can be studied by immunostaining of synaptonemal complexes (SCs), but in this case their frequency is probably underestimated due to the phenomenon of synaptic adjustment. They can also be studied in classic meiotic preparations, which, from a clinical point of view, is still the best approach, especially if multiplex fluorescence in situ hybridization is at hand to solve difficult cases. Sperm chromosome FISH studies also provide indirect evidence of their presence. Synaptic anomalies can affect the rate of recombination of all bivalents, produce achiasmate small univalents, partially achiasmate medium-sized or large bivalents, or affect all bivalents in the cell. The frequency is variable, interindividually and intraindividually. The baseline incidence of synaptic anomalies is 6-8%, which may be increased to 17.6% in males with a severe oligozoospermia, and to 27% in normozoospermic males with one or more previous IVF failures. The clinical consequences are the production of abnormal spermatozoa that will produce a higher number of chromosomally abnormal embryos. The indications for a meiotic study in testicular biopsy are provided.

  13. Evaluation of Cardiac Toxicity Biomarkers in Rats from Different Laboratories.

    Science.gov (United States)

    Kim, Kyuri; Chini, Naseem; Fairchild, David G; Engle, Steven K; Reagan, William J; Summers, Sandra D; Mirsalis, Jon C

    2016-12-01

    There is a great need for improved diagnostic and prognostic accuracy of potential cardiac toxicity in drug development. This study reports the evaluation of several commercially available biomarker kits by 3 institutions (SRI, Eli Lilly, and Pfizer) for the discrimination between myocardial degeneration/necrosis and cardiac hypertrophy as well as the assessment of the interlaboratory and interplatform variation in results. Serum concentrations of natriuretic peptides (N-terminal pro-atrial natriuretic peptide [NT-proANP] and N-terminal pro-brain natriuretic peptide [NT-proBNP]), cardiac and skeletal troponins (cTnI, cTnT, and sTnI), myosin light chain 3 (Myl3), and fatty acid binding protein 3 (FABP3) were assessed in rats treated with minoxidil (MNX) and isoproterenol (ISO). MNX caused increased heart-to-body weight ratios and prominent elevations in NT-proANP and NT-proBNP concentrations detected at 24-hr postdose without elevation in troponins, Myl3, or FABP3 and with no abnormal histopathological findings. ISO caused ventricular leukocyte infiltration, myocyte fibrosis, and necrosis with increased concentrations of the natriuretic peptides, cardiac troponins, and Myl3. These results reinforce the advantages of a multimarker strategy in elucidating the underlying cause of cardiac insult and detecting myocardial tissue damage at 24-hr posttreatment. The interlaboratory and interplatform comparison analyses also showed that the data obtained from different laboratories and platforms are highly correlated and reproducible, making these biomarkers widely applicable in preclinical studies.

  14. Sleep Apnea and Nocturnal Cardiac Arrhythmia: A Populational Study

    Directory of Open Access Journals (Sweden)

    Fatima Dumas Cintra

    2014-11-01

    Full Text Available Background: The mechanisms associated with the cardiovascular consequences of obstructive sleep apnea include abrupt changes in autonomic tone, which can trigger cardiac arrhythmias. The authors hypothesized that nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea. Objective: To analyze the relationship between obstructive sleep apnea and abnormal heart rhythm during sleep in a population sample. Methods: Cross-sectional study with 1,101 volunteers, who form a representative sample of the city of São Paulo. The overnight polysomnography was performed using an EMBLA® S7000 digital system during the regular sleep schedule of the individual. The electrocardiogram channel was extracted, duplicated, and then analyzed using a Holter (Cardio Smart® system. Results: A total of 767 participants (461 men with a mean age of 42.00 ± 0.53 years, were included in the analysis. At least one type of nocturnal cardiac rhythm disturbance (atrial/ventricular arrhythmia or beat was observed in 62.7% of the sample. The occurrence of nocturnal cardiac arrhythmias was more frequent with increased disease severity. Rhythm disturbance was observed in 53.3% of the sample without breathing sleep disorders, whereas 92.3% of patients with severe obstructive sleep apnea showed cardiac arrhythmia. Isolated atrial and ventricular ectopy was more frequent in patients with moderate/severe obstructive sleep apnea when compared to controls (p < 0.001. After controlling for potential confounding factors, age, sex and apnea-hypopnea index were associated with nocturnal cardiac arrhythmia. Conclusion: Nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea and the prevalence increases with disease severity. Age, sex, and the Apnea-hypopnea index were predictors of arrhythmia in this sample.

  15. Growth hormone and risk for cardiac tumors in Carney complex.

    Science.gov (United States)

    Bandettini, W Patricia; Karageorgiadis, Alexander S; Sinaii, Ninet; Rosing, Douglas R; Sachdev, Vandana; Schernthaner-Reiter, Marie Helene; Gourgari, Evgenia; Papadakis, Georgios Z; Keil, Meg F; Lyssikatos, Charalampos; Carney, J Aidan; Arai, Andrew E; Lodish, Maya; Stratakis, Constantine A

    2016-09-01

    Carney complex (CNC) is a multiple neoplasia syndrome that is caused mostly by PRKAR1A mutations. Cardiac myxomas are the leading cause of mortality in CNC patients who, in addition, often develop growth hormone (GH) excess. We studied patients with CNC, who were observed for over a period of 20 years (1995-2015) for the development of both GH excess and cardiac myxomas. GH secretion was evaluated by standard testing; dedicated cardiovascular imaging was used to detect cardiac abnormalities. Four excised cardiac myxomas were tested for the expression of insulin-like growth factor-1 (IGF-1). A total of 99 CNC patients (97 with a PRKAR1A mutation) were included in the study with a mean age of 25.8 ± 16.6 years at presentation. Over an observed mean follow-up of 25.8 years, 60% of patients with GH excess (n = 46) developed a cardiac myxoma compared with only 36% of those without GH excess (n = 54) (P = 0.016). Overall, patients with GH excess were also more likely to have a tumor vs those with normal GH secretion (OR: 2.78, 95% CI: 1.23-6.29; P = 0.014). IGF-1 mRNA and protein were higher in CNC myxomas than in normal heart tissue. We conclude that the development of cardiac myxomas in CNC may be associated with increased GH secretion, in a manner analogous to the association between fibrous dysplasia and GH excess in McCune-Albright syndrome, a condition similar to CNC. We speculate that treatment of GH excess in patients with CNC may reduce the likelihood of cardiac myxoma formation and/or recurrence of this tumor.

  16. Hypomelanosis of Ito with an unusual pulmonary abnormality in an infant

    Directory of Open Access Journals (Sweden)

    Ramesh Y Bhat

    2014-01-01

    Full Text Available Hypomelanosis of Ito (HI is a neurocutaneous syndrome characterized by hypopigmented cutaneous lesions and extracutaneous manifestations frequently affecting the nervous system and the musculoskeletal system. Dysmorphic features, dental, ophthalmic, gastrointestinal, cardiac, and renal abnormalities are described in a minority of patients. The authors describe a 4-month-old infant having HI with unusual pulmonary hypoplasia that has not been reported so far.

  17. Scintigraphic assessment of cardiac sympathetic innervation with I-123-metaiodobenzylguanidine in cardiomyopathy. Special reference to cardiac arrhythmia

    Energy Technology Data Exchange (ETDEWEB)

    Asano, Takahisa; Otsuka, Nobuaki; Sone, Teruki; Mimura, Hiroaki; Yanagimoto, Shinichi; Tomomitsu, Tatsushi; Fukunaga, Masao [Kawasaki Medical School, Kurashiki, Okayama (Japan); Morita, Koichi

    1999-07-01

    Cardiac sympathetic imagings with I-123-metaiodobenzylguanidine (MIBG) were carried out in 5 cases with dilated cardiomyopathy (DCM), 26 cases with hypertrophic cardiomyopathy (HCM), and 4 cases without cardiac disease as a control to assess cardiac sympathetic innervation qualitatively and quantitatively, and to clarify the relation of MIBG accumulation to arrhythmia. MIBG scintigraphy was performed at 15 min. (early image) and 4 hr. (delayed image) after intravenous injection of MIBG 111 MBq. The MIBG uptake ratio of mediastinum (H/M) and the cardiac washout rate (WR) from early to delayed images were calculated. On both early and delayed SPECTs, MIBG uptake was assessed by defect scores (DSs). Regarding the cases with HCM, the MIBG uptake ratio, WR, and DS were also compared in cases with and without arrhythmia. In DCM, the MIBG uptake on delayed SPECT was markedly low, the H/M ratio was significantly lower, and the DS was significantly higher than in the control (all p<0.05). As for the WR, there was no significant difference between HCM, DCM and the control. In HCM, significantly reduced MIBG uptake was observed in cases with ventricular techycardia (VT) and in cases with atrial fibrillation (Af), as compared with cases without arrhythmia (all p<0.05). There results suggest that MIBG scintigraphy might be a useful tool in the assessment of cardiac sympathetic abnormalities in cardiomyopathy, especially in cases with arrhythmia. (author)

  18. Cardiac fusion and complex congenital cardiac defects in thoracopagus twins: diagnostic value of cardiac CT

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Hyun Woo [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Park, Jeong-Jun [University of Ulsan College of Medicine, Asan Medical Center, Department of Pediatric Cardiac Surgery, Seoul (Korea, Republic of); Kim, Ellen Ai-Rhan [University of Ulsan College of Medicine, Asan Medical Center, Division of Neonatology, Department of Pediatrics, Seoul (Korea, Republic of); Won, Hye-Sung [University of Ulsan College of Medicine, Asan Medical Center, Department of Obstetrics and Gynecology, Seoul (Korea, Republic of)

    2014-09-15

    Most thoracopagus twins present with cardiac fusion and associated congenital cardiac defects, and assessment of this anatomy is of critical importance in determining patient care and outcome. Cardiac CT with electrocardiographic triggering provides an accurate and quick morphological assessment of both intracardiac and extracardiac structures in newborns, making it the best imaging modality to assess thoracopagus twins during the neonatal period. In this case report, we highlight the diagnostic value of cardiac CT in thoracopagus twins with an interatrial channel and complex congenital cardiac defects. (orig.)

  19. Cardiac and non-cardiac malformations produced by Mercury in hamsters. [None

    Energy Technology Data Exchange (ETDEWEB)

    Gale, T.F.

    1980-11-01

    The susceptibility of the developing mammalian embryo to the adverse effects of mercury is well documented. A variety of organic mercury compounds have been demonstrated to produce embryotoxic effects in experimental animals. HARADA recently summarized the reports of human intrauterine methylmercury poisoning, i.e., congenital Minamata disease, resulting from the ingestion of contaminated food. Ongoing studies in this laboratory have involved several different aspects of the embryotoxicity produced by inorganic mercury in hamsters including a dose response study, the interaction of mercuric acetate with cadmium and zinc, the effect of different routes of administration, the placental permeability of /sup 203/Hg and the embryotoxic response in several different hamster strains. Little is known regarding a human syndrome of congenital malformations characterized by ectopia cordis, internal cardiac defects and abnormalities of the diaphragm and ventral body wall. Most papers regarding this human syndrome are clinical reports describing the characteristics and management of specific cases; only speculative information is provided regarding etiology and possible embryopathic mechanisms. The observation that a similar syndrome, which will be designated CNC for cardiac and non-cardiac malformations, can be produced by mercury in hamsters prompted the present study. The specific goals of this study were 1) to study the effect of treating pregnant hamsters at different times during embryonic organogenesis to determine the time which produces the highest incidence of the CNC syndrome and whether different treatment times modify the morphological characteristics of the inclusive malformations and 2) to study the structural features of all mercury-induced external and internal abnormalities of the CNC syndrome in late gestation fetuses.

  20. Diagnostic accuracy of post-mortem MRI for thoracic abnormalities in fetuses and children

    Energy Technology Data Exchange (ETDEWEB)

    Arthurs, Owen J. [Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Radiology, London (United Kingdom); UCL Institute of Child Health, London (United Kingdom); Thayyil, Sudhin; Addison, Shea [Imperial College London, Perinatal Neurology and Neonatology, London (United Kingdom); Olsen, Oystein E. [Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Radiology, London (United Kingdom); Wade, Angie [UCL Institute of Child Health, Paediatric Epidemiology and Biostatistics Unit, London (United Kingdom); Jones, Rod; Norman, Wendy; Taylor, Andrew M. [UCL Institute of Cardiovascular Science, Centre for Cardiovascular Imaging, London (United Kingdom); Great Ormond Street Hospital for Children NHS Foundation Trust, Cardiorespiratory Division, London (United Kingdom); Scott, Rosemary J. [University College London Hospital NHS Trust, Department of Histopathology, London (United Kingdom); Robertson, Nicola J. [UCL Institute for Women' s Health, Academic Neonatology, London (United Kingdom); Chitty, Lyn S. [UCL Institute of Child Health, Genetics and Genomic Medicine, London (United Kingdom); UCLH NHS Foundation Trusts, London (United Kingdom); Sebire, Neil J. [Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Histopathology, London (United Kingdom); UCL Institute of Child Health, London (United Kingdom); Owens, Catherine M. [Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Radiology, London (United Kingdom); UCL Institute of Cardiovascular Science, Centre for Cardiovascular Imaging, London (United Kingdom); Great Ormond Street Hospital for Children NHS Foundation Trust, Cardiorespiratory Division, London (United Kingdom); Collaboration: Magnetic Resonance Imaging Autopsy Study (MaRIAS) Collaborative Group

    2014-11-15

    To compare the diagnostic accuracy of post-mortem magnetic resonance imaging (PMMR) specifically for non-cardiac thoracic pathology in fetuses and children, compared with conventional autopsy. Institutional ethics approval and parental consent was obtained. A total of 400 unselected fetuses and children underwent PMMR before conventional autopsy, reported blinded to the other dataset. Of 400 non-cardiac thoracic abnormalities, 113 (28 %) were found at autopsy. Overall sensitivity and specificity (95 % confidence interval) of PMMR for any thoracic pathology was poor at 39.6 % (31.0, 48.9) and 85.5 % (80.7, 89.2) respectively, with positive predictive value (PPV) 53.7 % (42.9, 64.0) and negative predictive value (NPV) 77.0 % (71.8, 81.4). Overall agreement was 71.8 % (67.1, 76.2). PMMR was most sensitive at detecting anatomical abnormalities, including pleural effusions and lung or thoracic hypoplasia, but particularly poor at detecting infection. PMMR currently has relatively poor diagnostic detection rates for the commonest intra-thoracic pathologies identified at autopsy in fetuses and children, including respiratory tract infection and diffuse alveolar haemorrhage. The reasonable NPV suggests that normal thoracic appearances at PMMR exclude the majority of important thoracic lesions at autopsy, and so could be useful in the context of minimally invasive autopsy for detecting non-cardiac thoracic abnormalities. (orig.)

  1. Epileptic Patients are at Risk of Cardiac Arrhythmias: A Novel Approach using QT-nomogram, Tachogram, and Cardiac Restitution Plots

    Science.gov (United States)

    Al-Nimer, Marwan S.; Al-Mahdawi, Sura A.; Abdullah, Namir M.; Al-Mahdawi, Akram

    2017-01-01

    Background: Sudden death is reported in patients who had a history of epilepsy and some authors believed that is due to cardiac arrhythmias. Objectives: This study aimed to predict that the epileptic patients are at risk of serious cardiac arrhythmias by QT-nomogram, tachogram (Lorenz), and cardiac restitution plots. Methods: A total number of 71 healthy subjects (Group I) and 64 newly diagnosed epileptic patients (Group II) were recruited from Al-Yarmouk and Baghdad Teaching hospitals in Baghdad from March 2015 to July 2015 and included in this study. The diagnosis of epilepsy achieved clinically, electroencephalograph record and radio-images including computerized tomography and magnetic image resonance. At the time of entry into the study, an electrocardiography (ECG) was done, and the determinants of each ECG record were calculated. The QT-nomogram, tachogram, and cardiac restitution plots were used to identify the patients at risk of cardiac arrhythmias. Results: Significant prolonged corrected QT corrected (QTc) and JT corrected intervals were observed in female compared with male at age ≥50 years while the TQ interval was significantly prolonged in males of Group II. Eight patients of Group II had a significant pathological prolonged QTc interval compared with undetectable finding in Group I. QT nomogram did not disclose significant findings while the plots of Lorenz and restitution steepness disclose that the patients of Group II were vulnerable to cardiac arrhythmias. Abnormal ECG findings were observed in the age extremities (≤18 years and ≥50 years) in Group II compared with Group I. Conclusion: Utilization of QT-nomogram, restitution steepness, and tachogram plots is useful tools for detection subclinical vulnerable epileptic patient with cardiac arrhythmias. PMID:28149075

  2. Epileptic patients are at risk of cardiac arrhythmias: A novel approach using QT-nomogram, tachogram, and cardiac restitution plots

    Directory of Open Access Journals (Sweden)

    Marwan S Al-Nimer

    2017-01-01

    Full Text Available Background: Sudden death is reported in patients who had a history of epilepsy and some authors believed that is due to cardiac arrhythmias. Objectives: This study aimed to predict that the epileptic patients are at risk of serious cardiac arrhythmias by QT-nomogram, tachogram (Lorenz, and cardiac restitution plots. Methods: A total number of 71 healthy subjects (Group I and 64 newly diagnosed epileptic patients (Group II were recruited from Al-Yarmouk and Baghdad Teaching hospitals in Baghdad from March 2015 to July 2015 and included in this study. The diagnosis of epilepsy achieved clinically, electroencephalograph record and radio-images including computerized tomography and magnetic image resonance. At the time of entry into the study, an electrocardiography (ECG was done, and the determinants of each ECG record were calculated. The QT-nomogram, tachogram, and cardiac restitution plots were used to identify the patients at risk of cardiac arrhythmias. Results: Significant prolonged corrected QT corrected (QTc and JT corrected intervals were observed in female compared with male at age ≥50 years while the TQ interval was significantly prolonged in males of Group II. Eight patients of Group II had a significant pathological prolonged QTc interval compared with undetectable finding in Group I. QT nomogram did not disclose significant findings while the plots of Lorenz and restitution steepness disclose that the patients of Group II were vulnerable to cardiac arrhythmias. Abnormal ECG findings were observed in the age extremities (≤18 years and ≥50 years in Group II compared with Group I. Conclusion: Utilization of QT-nomogram, restitution steepness, and tachogram plots is useful tools for detection subclinical vulnerable epileptic patient with cardiac arrhythmias.

  3. Cardiac nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Gerson, M.C.

    1987-01-01

    The book begins with a review of the radionuclide methods available for evaluating cardiac perfusion and function. The authors discuss planar and tomographic thallium myocardial imaging, first-pass and equilibrium radionuclide angiography, and imaging with infarct-avid tracers. Several common but more specialized procedures are then reviewed: nonogemetric measurement of left ventricular volume, phase (Fourier) analysis, stroke volume ratio, right ventricular function, and diastolic function. A separate chapter is devoted to drug interventions and in particular the use of radionuclide ventriculography to monitor doxorubicin toxicity and therapy of congestive heart failure. The subsequent chapters provide a comprehensive guide to test selection, accuracy, and results in acute myocardial infarction, in postmyocardial infarction, in chronic coronary artery disease, before and after medical or surgical revascularization, in valvular heart disease, in cardiomyopathies, and in cardiac trauma.

  4. Sudden Cardiac Death

    Directory of Open Access Journals (Sweden)

    Yipsy María Gutiérrez Báez

    2015-09-01

    Full Text Available Since the second half of the twentieth century, dying suddenly due to heart-related problems has become the main health issue in all countries where infectious diseases are not prevalent. Sudden death from cardiac causes is an important global health problem. Major databases were searched for the leading causes of sudden cardiac death. It has been demonstrated that there is a group of hereditary diseases with structural alterations or without apparent organic cause that explains many cases of sudden death in young people, whether related or not to physical exertion. Certain population groups are at higher risk for this disease. They are relatively easy to identify and can be the target of primary prevention measures.

  5. Cardiac arrhythmias in pregnancy.

    Science.gov (United States)

    Knotts, Robert J; Garan, Hasan

    2014-08-01

    As more women with repaired congenital heart disease survive to their reproductive years and many other women are delaying pregnancy until later in life, a rising concern is the risk of cardiac arrhythmias during pregnancy. Naturally occurring cardiovascular changes during pregnancy increase the likelihood that a recurrence of a previously experienced cardiac arrhythmia or a de novo arrhythmia will occur. Arrhythmias should be thoroughly investigated to determine if there is a reversible etiology, and risks/benefits of treatment options should be fully explored. We discuss the approach to working up and treating various arrhythmias during pregnancy with attention to fetal and maternal risks as well as treatment of fetal arrhythmias. Acute management in stable patients includes close monitoring and intravenous pharmacologic therapy, while DC cardioversion should be used to terminate arrhythmias in hemodynamically unstable patients. Long-term management may require continued oral antiarrhythmic therapy, with particular attention to fetal safety, to prevent complications associated with arrhythmias.

  6. Antiarrhythmic effect of growth factor-supplemented cardiac progenitor cells in chronic infarcted heart.

    Science.gov (United States)

    Savi, Monia; Bocchi, Leonardo; Rossi, Stefano; Frati, Caterina; Graiani, Gallia; Lagrasta, Costanza; Miragoli, Michele; Di Pasquale, Elisa; Stirparo, Giuliano G; Mastrototaro, Giuseppina; Urbanek, Konrad; De Angelis, Antonella; Macchi, Emilio; Stilli, Donatella; Quaini, Federico; Musso, Ezio

    2016-06-01

    c-Kit(pos) cardiac progenitor cells (CPCs) represent a successful approach in healing the infarcted heart and rescuing its mechanical function, but electrophysiological consequences are uncertain. CPC mobilization promoted by hepatocyte growth factor (HGF) and IGF-1 improved electrogenesis in myocardial infarction (MI). We hypothesized that locally delivered CPCs supplemented with HGF + IGF-1 (GFs) can concur in ameliorating electrical stability of the regenerated heart. Adult male Wistar rats (139 rats) with 4-wk-old MI or sham conditions were randomized to receive intramyocardial injection of GFs, CPCs, CPCs + GFs, or vehicle (V). Enhanced green fluorescent protein-tagged CPCs were used for cell tracking. Vulnerability to stress-induced arrhythmia was assessed by telemetry-ECG. Basic cardiac electrophysiological properties were examined by epicardial multiple-lead recording. Hemodynamic function was measured invasively. Hearts were subjected to anatomical, morphometric, immunohistochemical, and molecular biology analyses. Compared with V and at variance with individual CPCs, CPCs + GFs approximately halved arrhythmias in all animals, restoring cardiac anisotropy toward sham values. GFs alone reduced arrhythmias by less than CPCs + GFs, prolonging ventricular refractoriness without affecting conduction velocity. Concomitantly, CPCs + GFs reactivated the expression levels of Connexin-43 and Connexin-40 as well as channel proteins of key depolarizing and repolarizing ion currents differently than sole GFs. Mechanical function and anatomical remodeling were equally improved by all regenerative treatments, thus exhibiting a divergent behavior relative to electrical aspects. Conclusively, we provided evidence of distinctive antiarrhythmic action of locally injected GF-supplemented CPCs, likely attributable to retrieval of Connexin-43, Connexin-40, and Cav1.2 expression, favoring intercellular coupling and spread of excitation in mended heart.

  7. Low-set ears and pinna abnormalities

    Science.gov (United States)

    Low-set ears; Microtia; "Lop" ear; Pinna abnormalities; Genetic defect-pinna; Congenital defect-pinna ... conditions: Abnormal folds or location of the pinna Low-set ears No opening to the ear canal ...

  8. Apigenin ameliorates hypertension-induced cardiac hypertrophy and down-regulates cardiac hypoxia inducible factor-lα in rats.

    Science.gov (United States)

    Zhu, Zeng-Yan; Gao, Tian; Huang, Yan; Xue, Jie; Xie, Mei-Lin

    2016-04-01

    Apigenin is a natural flavonoid compound that can inhibit hypoxia-inducible factor (HIF)-1α expression in cultured tumor cells under hypoxic conditions. Hypertension-induced cardiac hypertrophy is always accompanied by abnormal myocardial glucolipid metabolism due to an increase of HIF-1α. However, whether or not apigenin may ameliorate the cardiac hypertrophy and abnormal myocardial glucolipid metabolism remains unknown. This study aimed to examine the effects of apigenin. Rats with cardiac hypertrophy induced by renovascular hypertension were treated with apigenin 50-100 mg kg(-1) (the doses can be achieved by pharmacological or dietary supplementation for an adult person) by gavage for 4 weeks. The results showed that after treatment with apigenin, the blood pressure, heart weight, heart weight index, cardiomyocyte cross-sectional area, serum angiotensin II, and serum and myocardial free fatty acids were reduced. It is important to note that apigenin decreased the expression level of myocardial HIF-1α protein. Moreover, apigenin simultaneously increased the expression levels of myocardial peroxisome proliferator-activated receptor (PPAR) α, carnitine palmitoyltransferase (CPT)-1, and pyruvate dehydrogenase kinase (PDK)-4 proteins and decreased the expression levels of myocardial PPARγ, glycerol-3-phosphate acyltransferase genes (GPAT), and glucose transporter (GLUT)-4 proteins. These findings demonstrated that apigenin could improve hypertensive cardiac hypertrophy and abnormal myocardial glucolipid metabolism in rats, and its mechanisms might be associated with the down-regulation of myocardial HIF-1α expression and, subsequently increasing the expressions of myocardial PPARα and its target genes CPT-1 and PDK-4, and decreasing the expressions of myocardial PPARγ and its target genes GPAT and GLUT-4.

  9. Cardiac surgery 2015 reviewed.

    Science.gov (United States)

    Doenst, Torsten; Strüning, Constanze; Moschovas, Alexandros; Gonzalez-Lopez, David; Essa, Yasin; Kirov, Hristo; Diab, Mahmoud; Faerber, Gloria

    2016-10-01

    For the year 2015, almost 19,000 published references can be found in PubMed when entering the search term "cardiac surgery". The last year has been again characterized by lively discussions in the fields where classic cardiac surgery and modern interventional techniques overlap. Lacking evidence in the field of coronary revascularization with either percutaneous coronary intervention or bypass surgery has been added. As in the years before, CABG remains the gold standard for the revascularization of complex stable triple-vessel disease. Plenty of new information has been presented comparing the conventional to transcatheter aortic valve implantation (TAVI) demonstrating similar short- and mid-term outcomes at high and low risk, but even a survival advantage with transfemoral TAVI at intermediate risk. In addition, there were many relevant and interesting other contributions from the purely operative arena. This review article will summarize the most pertinent publications in the fields of coronary revascularization, surgical treatment of valve disease, heart failure (i.e., transplantation and ventricular assist devices), and aortic surgery. While the article does not have the expectation of being complete and cannot be free of individual interpretation, it provides a condensed summary that is intended to give the reader "solid ground" for up-to-date decision-making in cardiac surgery.

  10. Cardiac tissue engineering

    Directory of Open Access Journals (Sweden)

    MILICA RADISIC

    2005-03-01

    Full Text Available We hypothesized that clinically sized (1-5 mm thick,compact cardiac constructs containing physiologically high density of viable cells (~108 cells/cm3 can be engineered in vitro by using biomimetic culture systems capable of providing oxygen transport and electrical stimulation, designed to mimic those in native heart. This hypothesis was tested by culturing rat heart cells on polymer scaffolds, either with perfusion of culture medium (physiologic interstitial velocity, supplementation of perfluorocarbons, or with electrical stimulation (continuous application of biphasic pulses, 2 ms, 5 V, 1 Hz. Tissue constructs cultured without perfusion or electrical stimulation served as controls. Medium perfusion and addition of perfluorocarbons resulted in compact, thick constructs containing physiologic density of viable, electromechanically coupled cells, in contrast to control constructs which had only a ~100 mm thick peripheral region with functionally connected cells. Electrical stimulation of cultured constructs resulted in markedly improved contractile properties, increased amounts of cardiac proteins, and remarkably well developed ultrastructure (similar to that of native heart as compared to non-stimulated controls. We discuss here the state of the art of cardiac tissue engineering, in light of the biomimetic approach that reproduces in vitro some of the conditions present during normal tissue development.

  11. [Phenomenology of abnormal body perceptions].

    Science.gov (United States)

    Schäfer, M L

    1983-01-01

    The present paper deals with the problematic nature of the phenomenological grasping of the consciousness of the body and its pathological modifications. The reasoning is oriented by the doctrine of Husserl of the so-called sentiments as the fundamentals of the experience of the own body. This basic approach does not only seem to be basically for a psychology of the consciousness of the body, but also to give the theoretical-conceptual structure for a great number of psychopathological modifications. Subsequent to a criticism of the conventional use of the term 'hallucination of the body' we attempt to chart elements of a scheme of the abnormal consciousness of the body.

  12. WAVELET ANALYSIS OF ABNORMAL ECGS

    Directory of Open Access Journals (Sweden)

    Vasudha Nannaparaju

    2014-02-01

    Full Text Available Detection of the warning signals by the heart can be diagnosed from ECG. An accurate and reliable diagnosis of ECG is very important however which is cumbersome and at times ambiguous in time domain due to the presence of noise. Study of ECG in wavelet domain using both continuous Wavelet transform (CWT and discrete Wavelet transform (DWT, with well known wavelet as well as a wavelet proposed by the authors for this investigation is found to be useful and yields fairly reliable results. In this study, Wavelet analysis of ECGs of Normal, Hypertensive, Diabetic and Cardiac are carried out. The salient feature of the study is that detection of P and T phases in wavelet domain is feasible which are otherwise feeble or absent in raw ECGs.

  13. Development of heart failure is independent of K+ channel-interacting protein 2 expression

    DEFF Research Database (Denmark)

    Speerschneider, Tobias; Grubb, Søren; Metoska, Artina;

    2013-01-01

    Abstract  Abnormal ventricular repolarization in ion channelopathies and heart disease is a major cause of ventricular arrhythmias and sudden cardiac death. K(+) channel-interacting protein 2 (KChIP2) expression is significantly reduced in human heart failure (HF), contributing to a loss...

  14. Intraoperative cardiac mapping in the treatment of an infant congenital fibroma.

    Science.gov (United States)

    Sakamoto, Shun-Ichiro; Shibata, Masafumi; Murata, Hiroshige; Nitta, Takashi

    2015-03-01

    Surgical treatment for ventricular tachycardia associated with congenital cardiac tumors is rare. Intraoperative electroanatomic mapping was performed in a 23-month-old female infant to identify the arrhythmogenic substrate of the epicardium before tumor resection. Verification of the localized abnormal electrocardiogram on the tumor in the treatment of ventricular tachycardia was useful for successful partial resection and cryoablation of the giant fibroma.

  15. On Regularity of Abnormal Subriemannian Geodesics

    CERN Document Server

    Tan, Kanghai

    2012-01-01

    We prove the smoothness of abnormal minimizers of subriemannian manifolds of step 3 with a nilpotent basis. We prove that rank 2 Carnot groups of step 4 admit no strictly abnormal minimizers. For any subriemannian manifolds of step less than 7, we show all abnormal minimizers have no corner type singularities, which partly generalize the main result of Leonardi-Monti.

  16. Evaluation of apical subtype of hypertrophic cardiomyopathy using cardiac magnetic resonance imaging with gadolinium enhancement.

    Science.gov (United States)

    Kebed, Kalie Y; Al Adham, Raed I; Bishu, Kalkidan; Askew, J Wells; Klarich, Kyle W; Araoz, Philip A; Foley, Thomas A; Glockner, James F; Nishimura, Rick A; Anavekar, Nandan S

    2014-09-01

    Apical hypertrophic cardiomyopathy (HC) is an uncommon variant of HC. We sought to characterize cardiac magnetic resonance imaging (MRI) findings among apical HC patients. This was a retrospective review of consecutive patients with a diagnosis of apical HC who underwent cardiac MRI examinations at the Mayo Clinic (Rochester, MN) from August 1999 to October 2011. Clinical and demographic data at the time of cardiac MRI study were abstracted. Cardiac MRI study and 2-dimensional echocardiograms performed within 6 months of the cardiac MRI were reviewed; 96 patients with apical HC underwent cardiac MRI examinations. LV end-diastolic and end-systolic volumes were 130.7 ± 39.1 ml and 44.2 ± 20.9 ml, respectively. Maximum LV thickness was 19 ± 5 mm. Hypertrophy extended beyond the apex into other segments in 57 (59.4%) patients. Obstructive physiology was seen in 12 (12.5%) and was more common in the mixed apical phenotype than the pure apical (19.3 vs 2.6%, p = 0.02). Apical pouches were noted in 39 (40.6%) patients. Late gadolinium enhancement (LGE) was present in 70 (74.5%) patients. LGE was associated with severe symptoms and increased maximal LV wall thickness. In conclusion, cardiac MRI is well suited for studying the apical form of HC because of difficulty imaging the cardiac apex with standard echocardiography. Cardiac MRI is uniquely suited to delineate the presence or absence of an apical pouch and abnormal myocardial LGE that may have implications in the natural history of apical HM. In particular, the presence of abnormal LGE is associated with clinical symptoms and increased wall thickness.

  17. Fibrosis and Cardiac Arrhythmias

    NARCIS (Netherlands)

    de Jong, Sanne; van Veen, Toon A. B.; van Rijen, Harold V. M.; de Bakker, Jacques M. T.

    2011-01-01

    In this review article about fibrosis and arrhythmias, we show that the amount of collagen, a normal element of the heart muscle, increases with age and in heart disease. The relation between fibrosis and electrophysiological parameters such as conduction, fractionation of electrograms, abnormal imp

  18. Chromosomal phenotypes and submicroscopic abnormalities

    Directory of Open Access Journals (Sweden)

    Devriendt Koen

    2004-01-01

    Full Text Available Abstract The finding, during the last decade, that several common, clinically delineated syndromes are caused by submicroscopic deletions or, more rarely, by duplications, has provided a powerful tool in the annotation of the human genome. Since most microdeletion/microduplication syndromes are defined by a common deleted/duplicated region, abnormal dosage of genes located within these regions can explain the phenotypic similarities among individuals with a specific syndrome. As such, they provide a unique resource towards the genetic dissection of complex phenotypes such as congenital heart defects, mental and growth retardation and abnormal behaviour. In addition, the study of phenotypic differences in individuals with the same microdeletion syndrome may also become a treasury for the identification of modifying factors for complex phenotypes. The molecular analysis of these chromosomal anomalies has led to a growing understanding of their mechanisms of origin. Novel tools to uncover additional submicroscopic chromosomal anomalies at a higher resolution and higher speed, as well as the novel tools at hand for deciphering the modifying factors and epistatic interactors, are 'on the doorstep' and will, besides their obvious diagnostic role, play a pivotal role in the genetic dissection of complex phenotypes.

  19. Abnormal visuomotor processing in schizophrenia

    Directory of Open Access Journals (Sweden)

    Siân E. Robson

    2016-01-01

    Full Text Available Subtle disturbances of visual and motor function are known features of schizophrenia and can greatly impact quality of life; however, few studies investigate these abnormalities using simple visuomotor stimuli. In healthy people, electrophysiological data show that beta band oscillations in sensorimotor cortex decrease during movement execution (event-related beta desynchronisation (ERBD, then increase above baseline for a short time after the movement (post-movement beta rebound (PMBR; whilst in visual cortex, gamma oscillations are increased throughout stimulus presentation. In this study, we used a self-paced visuomotor paradigm and magnetoencephalography (MEG to contrast these responses in patients with schizophrenia and control volunteers. We found significant reductions in the peak-to-peak change in amplitude from ERBD to PMBR in schizophrenia compared with controls. This effect was strongest in patients who made fewer movements, whereas beta was not modulated by movement in controls. There was no significant difference in the amplitude of visual gamma between patients and controls. These data demonstrate that clear abnormalities in basic sensorimotor processing in schizophrenia can be observed using a very simple MEG paradigm.

  20. Indeterminacy of Spatiotemporal Cardiac Alternans

    CERN Document Server

    Zhao, Xiaopeng

    2007-01-01

    Cardiac alternans, a beat-to-beat alternation in action potential duration (at the cellular level) or in ECG morphology (at the whole heart level), is a marker of ventricular fibrillation, a fatal heart rhythm that kills hundreds of thousands of people in the US each year. Investigating cardiac alternans may lead to a better understanding of the mechanisms of cardiac arrhythmias and eventually better algorithms for the prediction and prevention of such dreadful diseases. In paced cardiac tissue, alternans develops under increasingly shorter pacing period. Existing experimental and theoretical studies adopt the assumption that alternans in homogeneous cardiac tissue is exclusively determined by the pacing period. In contrast, we find that, when calcium-driven alternans develops in cardiac fibers, it may take different spatiotemporal patterns depending on the pacing history. Because there coexist multiple alternans solutions for a given pacing period, the alternans pattern on a fiber becomes unpredictable. Usin...

  1. Sudden Cardiac Arrest due to Brugada Syndrome: a Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    R Soleimanirad

    2013-04-01

    Full Text Available Brugada Syndrome is a rare cause of sudden cardiac arrest and has a unique ECG pattern. In fact, with ST-segment elevation down sloping in the right precordial leads (v1-v3, RBBB pattern in lateral leads and J-point elevation is revealed. We must notice and avoid trigger factors of this syndrome during general anesthesia. Patient is a 39 old man who attended to emergency department with sudden cardiac arrest and resuscitate. He was transferred to ICU for management of hypoxic ischemic encephalopathy. Complementary studies concluded the diagnosis of Brugada syndrome. We must consider Brugada syndrome within patients with family history of sudden cardiac arrest. Moreover, we must avoid trigger factors of this syndrome such as fever, bradicardia and electrolyte abnormality (specialy Na, Ca abnormalities during general anesthesia and if they appear, we should treat them.

  2. Coronary artery anomalies overview: The normal and the abnormal

    Institute of Scientific and Technical Information of China (English)

    Adriana DM Villa; Eva Sammut; Arjun Nair; Ronak Rajani; Rodolfo Bonamini; Amedeo Chiribiri

    2016-01-01

    The aim of this review is to give a comprehensive and concise overview of coronary embryology and normal coronary anatomy, describe common variants of normal and summarize typical patterns of anomalous coronary artery anatomy. Extensive iconography supports the text, with particular attention to images obtained in vivo using non-invasive imaging. We have divided this article into three groups, according to their frequency in the general population: Normal, normal variant and anomaly. Although congenital coronary artery anomalies are relatively uncommon, they are the second most common cause of sudden cardiac death among young athletes and therefore warrant detailed review. Based on the functional relevance of each abnormality, coronary artery anomalies can be classified as anomalies with obligatory ischemia, without ischemia or with exceptional ischemia. The clinical symptoms may include chest pain, dyspnea, palpitations, syncope, cardiomyopathy, arrhythmia, myocardial infarction and sudden cardiac death. Moreover, it is important to also identify variants and anomalies without clinical relevance in their own right as complications during surgery or angioplasty can occur.

  3. Calcium-activated potassium conductances contribute to action potential repolarization at the soma but not the dendrites of hippocampal CA1 pyramidal neurons.

    Science.gov (United States)

    Poolos, N P; Johnston, D

    1999-07-01

    Evidence is accumulating that voltage-gated channels are distributed nonuniformly throughout neurons and that this nonuniformity underlies regional differences in excitability within the single neuron. Previous reports have shown that Ca2+, Na+, A-type K+, and hyperpolarization-activated, mixed cation conductances have varying distributions in hippocampal CA1 pyramidal neurons, with significantly different densities in the apical dendrites compared with the soma. Another important channel mediates the large-conductance Ca2+-activated K+ current (IC), which is responsible in part for repolarization of the action potential (AP) and generation of the afterhyperpolarization that follows the AP recorded at the soma. We have investigated whether this current is activated by APs retrogradely propagating in the dendrites of hippocampal pyramidal neurons using whole-cell dendritic patch-clamp recording techniques. We found no IC activation by back-propagating APs in distal dendritic recordings. Dendritic APs activated IC only in the proximal dendrites, and this activation decayed within the first 100-150 micrometer of distance from the soma. The decay of IC in the proximal dendrites occurred despite AP amplitude, plus presumably AP-induced Ca2+ influx, that was comparable with that at the soma. Thus we conclude that IC activation by action potentials is nonuniform in the hippocampal pyramidal neuron, which may represent a further example of regional differences in neuronal excitability that are determined by the nonuniform distribution of voltage-gated channels in dendrites.

  4. IQGAP and mitotic exit network (MEN) proteins are required for cytokinesis and re-polarization of the actin cytoskeleton in the budding yeast, Saccharomyces cerevisiae.

    Science.gov (United States)

    Corbett, Mark; Xiong, Yulan; Boyne, James R; Wright, Daniel J; Munro, Ewen; Price, Clive

    2006-11-01

    In budding yeast the final stages of the cell division cycle, cytokinesis and cell separation, are distinct events that require to be coupled, both together and with mitotic exit. Here we demonstrate that mutations in genes of the mitotic exit network (MEN) prevent cell separation and are synthetically lethal in combination with both cytokinesis and septation defective mutations. Analysis of the synthetic lethal phenotypes reveals that Iqg1p functions in combination with the MEN components, Tem1p, Cdc15p Dbf20p and Dbf2p to govern the re-polarization of the actin cytoskeleton to either side of the bud neck. In addition phosphorylation of the conserved PCH protein, Hof1p, is dependent upon these activities and requires actin ring assembly. Recruitment of Dbf2p to the bud neck is dependent upon actin ring assembly and correlates with Hof1p phosphorylation. Failure to phosphorylate Hof1p results in the increased stability of the protein and its persistence at the bud neck. These data establish a mechanistic dependency of cell separation upon an intermediate step requiring actomyosin ring assembly.

  5. Experimental Study of the Effect of Autonomic Nervous System on the Transmural Dispersion of Ventricular Repolarization under Acute Myocardial Ischemia in Vivo

    Institute of Scientific and Technical Information of China (English)

    张存泰; 徐大文; 李泱; 刘念; 钟江华; 王琳; 陆再英

    2002-01-01

    Summary: The effect of the autonomic nerves on the transmural dispersion of ventricular repolariza tion (TDR) under acute myocardial ischemia in intact canine was investigated. Using the monophasic action potential (MAP) recording technique, MAPs of the epicardium (Epi), midmyocardium (Mid) and endocardium (Endo) were recorded simultaneously by specially designed plunge-needle electrodes at the left ventricular free wall under acute myocardial ischemia in 12 open-chest dogs.MAPD90 and TDR among three myocardial layers as well as the incidence of the early afterdepolar ization (EAD) before autonomic nervous stimulation and during autonomic nervous stimulation were compared. It was found that 10 min after acute myocardial I~hemia, TDR was increased from 55±8.ms to 86± 15 ms during sympathetic stimulation (P<0. 01). The TDR (53± 9 ms) during parasympathetic stimulation was not significantly different from that of the control (55±8 ms) (P>0.05). The EAD was elicited in the Mid of 2 dogs (16 %) 10 min after acute myocardial ischemia,but the EAD were elicited in the Mid of 7 dogs (58 %) during sympathetic stimulation (P<0. 01).It was concluded that: (1) Sympathetic stimulation can increase the transmural dispersion of repolari zation and induce early afterdepolarizations in the Mid under acute myocardial ischemia, which pro-vide the opportunity for the ventricular arrhythmia developing; (2) Parasympathetic stimulation has no significant effect on the transmural dispersion of repolarization under myocardial ischemia.

  6. Regional pericarditis status post cardiac ablation: A case report

    Directory of Open Access Journals (Sweden)

    Joseph Orme

    2014-01-01

    Full Text Available Context: Regional pericarditis is elusive and difficult to diagnosis. Healthcare providers should be familiar with post-cardiac ablation complications as this procedure is now widespread and frequently performed. The management of regional pericarditis differs greatly from that of acute myocardial infarction. Case report: A 52 year-old male underwent atrial fibrillation ablation and developed severe mid-sternal chest pain the following day with electrocardiographic findings suggestive of acute myocardial infarction, and underwent coronary angiography, a left ventriculogram, and 2D transthoracic echocardiogram, all of which were unremarkable without evidence of obstructive coronary disease, wall motion abnormalities, or pericardial effusions. Ultimately, the patient was diagnosed with regional pericarditis. After diagnosis, the patient′s presenting symptoms resolved with treatment including nonsteroidal anti-inflammatory agents and colchicine. Conclusion: This is the first reported case study of regional pericarditis status post cardiac ablation. Electrocardiographic findings were classic for an acute myocardial infarction; however, coronary angiography and left ventriculogram demonstrated no acute coronary occlusion or ventricular wall motion abnormalities. Healthcare professionals must remember that the electrocardiographic findings in pericarditis are not always classic and that pericarditis can occur status post cardiac ablation.

  7. Role of Sodium Channel on Cardiac Action Potential

    Directory of Open Access Journals (Sweden)

    S. H. Sabzpoushan

    2012-06-01

    Full Text Available Sudden cardiac death is a major cause of death worldwide. In most cases, it's caused by abnormal action potential propagation that leads to cardiac arrhythmia. The aim of this article is to study the abnormal action potential propagation through sodium ion concentration variations. We use a new electrophysiological model that is both detailed and computationally efficient. This efficient model is based on the partial differential equation method. The central finite difference method is used for numerical solving of the two-dimensional (2D wave propagation equation. Simulations are implemented in two stages, as a single cardiac cell and as a two-dimensional grid of cells. In both stages, the normal action potential formation in case of a single cell and it's normal propagation in case of a two-dimensional grid of cells were simulated with nominal sodium ion conductance. Then, the effect of sodium ion concentration on the action potential signal was studied by reducing the sodium ion conductance. It is concluded that reducing the sodium ion conductance, decreases both passing ability and conduction velocity of the action potential wave front.

  8. Case Report: Penetrating Cardiac Injury

    Directory of Open Access Journals (Sweden)

    Adem Grbolar

    2013-10-01

    Full Text Available Summary: Penetrating cardiac injurys caused by gunshots and penetrating tools have high mortality rates. The way of injury, how the cardiac area is effected and the presence of cardiac tamponadecauses mortality in different rates. However the better treatment quality of hospitals, increasingoperative techniques, and internel care unit quality has not been change during the years. Searching the literature, we want to present a 42 years old male patient whowas injured by knife and had a 1 cm skin wound on chest with cardiac tamponade. After sternotomy a 7 cm laseration was observed in heart. Cardioraphy was performed.

  9. Cardiac surgery for Kartagener syndrome.

    Science.gov (United States)

    Tkebuchava, T; von Segesser, L K; Niederhäuser, U; Bauersfeld, U; Turina, M

    1997-01-01

    Two patients (one girl, one boy) with Kartagener syndrome (situs inversus, bronchiectasis, sinusitis), despite pulmonary problems and associated congenital cardiac anomalies, were operated on at the ages of 4 years and 7 years, respectively. They had had previous palliative treatment at the age of 3 months and 1.3 years, respectively. Both postoperative periods after total correction were without significant complications. Long-term follow-up was available for 9 and 19 years, respectively, with no manifestations of heart insufficiency. Both patients are physically active, and neither requires cardiac medication. Patients with Kartagener syndrome and associated congenital cardiac anomalies can successfully undergo multiple cardiac operations with good long-term outcome.

  10. Ductus venosus in the first trimester: contribution to screening of chromosomal, cardiac defects and monochorionic twin complications.

    Science.gov (United States)

    Maiz, Nerea; Nicolaides, Kypros H

    2010-01-01

    In the first trimester the ductus venosus can be easily identified with color Doppler and a ductus venosus waveform can be obtained by pulsed Doppler. At 11-13 weeks the prevalence of abnormal a-wave in the ductus venosus is inversely related to fetal crown-rump length and maternal serum pregnancy-associated plasma protein-A (PAPP-A), increases with fetal nuchal translucency (NT) thickness and is more common in women of Black racial origin and in fetuses with abnormal karyotype or cardiac defects. Ductus venosus flow provides an independent contribution in the prediction of chromosomal abnormalities when combined with NT and the maternal serum markers of PAPP-A and free beta-hCG, increasing the detection rate to 96% at a false-positive rate of 2.6%. Abnormal ductus venosus flow increases the risk of cardiac defects in fetuses with NT above the 95th centile, and it may increase the risk in fetuses with normal NT. In twin pregnancies, abnormal ductus venosus flow is associated with chromosomal abnormalities and cardiac defects. In monochorionic twins, abnormal flow in the ductus venosus in at least 1 of the fetuses increases the risk of developing twin-to-twin transfusion syndrome.

  11. Pattern-based approach to fetal congenital cardiovascular anomalies using the transverse aortic arch view on prenatal cardiac MRI

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Su-Zhen; Zhu, Ming [Shanghai Jiaotong University School of Medicine, Department of Radiology, Shanghai Children' s Medical Center, Shanghai (China)

    2015-05-01

    Fetal echocardiography is the imaging modality of choice for prenatal diagnosis of congenital cardiovascular anomalies. However, echocardiography has limitations. Fetal cardiac magnetic resonance imaging (MRI) has the potential to complement US in detecting congenital cardiovascular anomalies. This article draws on our experience; it describes the transverse aortic arch view on fetal cardiac MRI and important clues on an abnormal transverse view at the level of the aortic arch to the diagnosis of fetal congenital cardiovascular anomalies. (orig.)

  12. Effect of impaired glucose tolerance on cardiac dysfunction in a rat model of prediabetes

    Institute of Scientific and Technical Information of China (English)

    LIANG Jia-liang; FENG Zhi-kuan; LIU Xiao-ying; LIN Qiu-xiong; FU Yong-heng; SHAN Zhi-xin; ZHU Jie-ning; LIN Shu-guang; YU Xi-yong

    2011-01-01

    Background The effect of impaired glucose tolerance (IGT) on cardiac function during the chronic prediabetes state is complicated and plays an important role in clinical outcome. However, the molecular mechanisms are not fully understood. This study was designed to observe cardiac dysfunction in prediabetic rats with IGT and to determine whether glucose metabolic abnormalities, inflammation and apoptosis are linked to it.Methods The IGT rat models were induced by streptozocin, and the heart functions were assessed by echocardiography.Myocardial glucose metabolism was analyzed by glycogen periodic acid-Schiff staining, and the pro-apoptotic effect of IGT was evaluated by TUNEL staining. Additionally, caspase-3 activation, macrophage migration inhibitory factor (MIF) and G-protein coupled receptor kinase 2 (GRK2) were detected by Western blotting in cardiac tissue lysates.Results Area-under-the-curve of blood glucose in rats injected with streptozotocin was higher than that in controls,increased by 16.28%, 38.60% and 38.61% at 2, 4 and 6 weeks respectively (F=15.370, P=0.003). Abnormal cardiac functions and apoptotic cardiomyocytes were observed in the IGT rats, the ejection fraction (EF) being (68.59±6.62)% in IGT rats vs. (81.07±4.59)% in controls (t=4.020, P=0.002). There was more glucose which was converted to glycogen in the myocardial tissues of IGT rats, especially in cardiac perivascular tissues. Compared to controls, the cleaved caspase-3, MIF and GRK2 were expressed at higher levels in the myocardial tissues of IGT rats.Conclusions IGT in the prediabetes period resulted in cardiac dysfunction linked to abnormal glycogen storage and apoptosis. Additionally, MIF and GRK2 may be involved in the pathogenesis of cardiac dysfunction in prediabetes and their regulation may contribute to the design of novel diagnostic and therapeutic strategies for those who have potential risks for diabetic cardiovascular complications.

  13. Fetal extracardiac anomalies associated with congenital cardiac diseases

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Bum Ha; Cho, Jung Yeon; Lee, Young Ho; Song, Mi Jin [Samsung Cheil Hospital, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2004-06-15

    To evaluate the incidence of associated extracardiac anomalies in fetuses with congenital heart defects on fetal echocardiography, and to estimate the incidence of chromosomal abnormalities according to the extracardiac anomalies. From Jan. 1999 to Dec. 2001, 101 fetuses with prenatally diagnosed extracardiac anomalies and congenital cardiac diseases were selected for study. The mean gestational age at the time of the ultrasound exam was about 25 weeks. Associated extracardiac anomalies were classified into CNS, face and neck, thorax, abdomen, genitourinary system, musculoskeletal, other and multi-systemic anomalies groups. Chromosomal studies including chorionic villi sampling, amniocentesis, cordocentesis, and postnatal exam were correlated. Musculoskeletal anomalies were the most commonly associated extracardiac anomalies (n=28, 27.7%). Abdominal anomaly (n=26, 25.7%), central nervous system anomaly (n=25, 24.8%), genitourinary anomaly(n=12, 11.9%), thoracic anomaly (n=4, 4%), face and neck anomaly (n=3, 3%) were found. Twenty eight fetuses showed other anomalies (n=28, 27.7%). Multi-systemic anomalies were also common (n=20, 19.8%). Fetal anomalies involving two systems were noted in 15 fetuses, and anomalies of more than three systems were not uncommon (5 fetuses). Chromosomal study of 38 fetuses revealed 19 fetuses with abnormal karyotypes (50%). For 19 fetuses with abnormal karyotypes, central nervous system anomalies and musculoskeletal anomalies were the most frequently associated with extracardiac abnormalities (n=9). Multi-systemic anomalies were associated in 9 of the 19 fetuses. In fetuses with cardiac defects, the musculoskeletal, abdomen and CNS anomalies were commonly associated with extracardiac anomalies. Various extracardiac anomalies such as, head and neck anomalies, CNS anomalies, musculoskeletal anomalies, and multi-organ anomalies were highly correlated with chromosomal abnormalities, and so this relationship requires chromosomal study.

  14. Abnormal Returns and Contrarian Strategies

    Directory of Open Access Journals (Sweden)

    Ivana Dall'Agnol

    2003-12-01

    Full Text Available We test the hypothesis that strategies which are long on portfolios of looser stocks and short on portfolios of winner stocks generate abnormal returns in Brazil. This type of evidence for the US stock market was interpreted by The Bondt and Thaler (1985 as reflecting systematic evaluation mistakes caused by investors overreaction to news related to the firm performance. We found evidence of contrarian strategies profitability for horizons from 3 months to 3 years in a sample of stock returns from BOVESPA and SOMA from 1986 to 2000. The strategies are more profitable for shorter horizons. Therefore, there was no trace of the momentum effect found by Jagadeesh and Titman (1993 for the same horizons with US data. There are remaing unexplained positive returns for contrarian strategies after accounting for risk, size, and liquidity. We also found that the strategy profitability is reduced after the Real Plan, which suggests that the Brazilian stock market became more efficient after inflation stabilization.

  15. Choreoathetosis after cardiac surgery with hypothermia and extracorporeal circulation.

    Science.gov (United States)

    Gherpelli, J L; Azeka, E; Riso, A; Atik, E; Ebaid, M; Barbero-Marcial, M

    1998-08-01

    Eleven children, 4-48 months old, with congenital cyanotic heart defects developed choreoathetoid movements 2-12 days after cardiac surgery with hypothermia and extracorporeal circulation (ECC). The abnormal movements mainly involved the limbs, facial musculature, and tongue, leading to a severe dysphagia. The symptoms had an acute onset, after a period of apparent neurologic normality, and had a variable outcome. Of the nine children that survive, three had abnormal movements when last seen (41 days to 12 months of follow-up). The other six children had a complete regression of the choreoathetoid movements 1-4 weeks after onset. No specific finding was observed in the CT scans, cerebrospinal fluid examination, or EEG that could be related to the abnormal movements. Symptomatic therapy with haloperidol with or without benzodiazepines led to symptomatic improvement in six children, although there was no evidence that this treatment modified the evolution of the disease. The authors conclude that the choreoathetoid syndrome after cardiac surgery with deep hypothermia and ECC is an ill-defined entity requiring additional study to better understand its pathogenesis so that preventive measures can be taken to avoid a condition that can lead to permanent and incapacitating neurologic sequelae.

  16. Fetal cardiac effects of maternal hyperglycemia during pregnancy.

    Science.gov (United States)

    Corrigan, Niamh; Brazil, Derek P; McAuliffe, Fionnuala

    2009-06-01

    Maternal diabetes mellitus is associated with increased teratogenesis, which can occur in pregestational type 1 and type 2 diabetes. Cardiac defects and with neural tube defects are the most common malformations observed in fetuses of pregestational diabetic mothers. The exact mechanism by which diabetes exerts its teratogenic effects and induces embryonic malformations is unclear. Whereas the sequelae of maternal pregestational diabetes, such as modulating insulin levels, altered fat levels, and increased reactive oxygen species, may play a role in fetal damage during diabetic pregnancy, hyperglycemia is thought to be the primary teratogen, causing particularly adverse effects on cardiovascular development. Fetal cardiac defects are associated with raised maternal glycosylated hemoglobin levels and are up to five times more likely in infants of mothers with pregestational diabetes compared with those without diabetes. The resulting anomalies are varied and include transposition of the great arteries, mitral and pulmonary atresia, double outlet of the right ventricle, tetralogy of Fallot, and fetal cardiomyopathy.A wide variety of rodent models have been used to study diabetic teratogenesis. Both genetic and chemically induced models of type 1 and 2 diabetes have been used to examine the effects of hyperglycemia on fetal development. Factors such as genetic background as well as confounding variables such as obesity appear to influence the severity of fetal abnormalities in mice. In this review, we will summarize recent data on fetal cardiac effects from human pregestational diabetic mothers, as well as the most relevant findings in rodent models of diabetic cardiac teratogenesis.

  17. Study on clinical symptoms in canine cardiac diseases

    Directory of Open Access Journals (Sweden)

    F. Karlette Anne

    Full Text Available Cardiac diseases in canines are an extensively studied phenomenon all over the world but meagre information has been reported in India. Certain problems, including historical, physical, and laboratory abnormalities, are associated with cardiovascular or pulmonary disease. In India however, the recognition of canine cardiac diseases has been delayed, and ignored on account of lack of awareness and knowledge by the owner and inadequate diagnostic facility to a field veterinarian. Considering the above facts, the present study was undertaken in Gujarat to survey the prevalence of common cardiac diseases in hospital population of dogs along with the clinical symptoms which often goes undetected due to lack of proper diagnostic techniques to be implied and the most forms of heart disease may be present for many years before any evidence of failure develops. In the present study most of the clinical cases of cardiac diseases were presented with a history of nocturnal coughing (seven cases; 2.55%, exercise intolerance (five cases; 1.82%, partial or complete anorexia (five cases; 1.82%, swelling in abdominal area (four cases; 1.45%, dullness and depression (two cases; 0.72%, cachexia and hepatojugular pulsation (one case each; 0.36% each at times. [Vet World 2009; 2(8.000: 307-309

  18. Cardiac Function in Long-Term Survivors of Childhood Lymphoma

    Directory of Open Access Journals (Sweden)

    Mark K. Friedberg

    2011-01-01

    Full Text Available Objectives. We studied long-term effects of therapy for childhood lymphoma on cardiac function. Design and patients. We prospectively evaluated 45 survivors of childhood lymphoma, using clinical parameters, electrocardiography and echocardiography. Further comparisons were made between lymphoma subgroups and between males and females. Results. Mean age at diagnosis was 9.1 years. Mean followup duration was 10.9 years. The NYHA functional class was I in 43 patients and II in 2 patients. A prolonged QTc interval (>0.44 msec was found in 8 patients. Left ventricular (LV systolic function and compliance were normal (LV shortening fraction 40±5.6%; cardiac index 2.84±1.13 L/min/m2; E/A wave ratio 2.5±1.3; mean ± S.D., LV mass was normal (97±40 grams/m2, mean ± S.D.. Mitral regurgitation was observed in 7/45 patients (16%. Asymptomatic pericardial effusions were found in 3/45 (7% patients. Conclusions. Long-term follow-up shows that most parameters of cardiac function are normal in survivors of childhood lymphoma. This is likely due to relatively low doses of anthracyclines in modern protocol modalities. Abnormalities in mitral valve flow, QTc prolongation and in a small proportion of survivors, and functional capacity necessitate long-term cardiac follow-up of these patients.

  19. Hypokalemia and sudden cardiac death

    DEFF Research Database (Denmark)

    Kjeldsen, Keld

    2010-01-01

    Worldwide, approximately three million people suffer sudden cardiac death annually. These deaths often emerge from a complex interplay of substrates and triggers. Disturbed potassium homeostasis among heart cells is an example of such a trigger. Thus, hypokalemia and, also, more transient...... of fatal arrhythmia and sudden cardiac death a patient is, the more attention should be given to the potassium homeostasis....

  20. The Danish Cardiac Rehabilitation Database

    DEFF Research Database (Denmark)

    Zwisler, Ann-Dorthe; Rossau, Henriette Knold; Nakano, Anne

    2016-01-01

    AIM OF DATABASE: The Danish Cardiac Rehabilitation Database (DHRD) aims to improve the quality of cardiac rehabilitation (CR) to the benefit of patients with coronary heart disease (CHD). STUDY POPULATION: Hospitalized patients with CHD with stenosis on coronary angiography treated with percutane...

  1. Biosynthesis of cardiac natriuretic peptides

    DEFF Research Database (Denmark)

    Goetze, Jens Peter

    2010-01-01

    . An inefficient post-translational prohormone maturation will also affect the biology of the cardiac natriuretic peptide system. This review aims at summarizing the myocardial synthesis of natriuretic peptides focusing on B-type natriuretic peptide, where new data has disclosed cardiac myocytes as highly...

  2. [Cardiac myxoma with cerebral metastases].

    Science.gov (United States)

    Bazin, A; Peruzzi, P; Baudrillard, J C; Pluot, M; Rousseaux, P

    1987-01-01

    A 56 year old woman developed multiple metastases in the cerebrum and cerebellum, four years after cardiac intervention on a left atrial myxoma. The absence of stroke is noteworthy. Multiple high density lesions with contrast enhancement were seen by CT scan, suggesting metastatic neoplasms. Histological examination confirmed the diagnosis of metastases of cardiac myxoma. Only four cases were recorded in the literature.

  3. Health Instruction Packages: Cardiac Anatomy.

    Science.gov (United States)

    Phillips, Gwen; And Others

    Text, illustrations, and exercises are utilized in these five learning modules to instruct nurses, students, and other health care professionals in cardiac anatomy and functions and in fundamental electrocardiographic techniques. The first module, "Cardiac Anatomy and Physiology: A Review" by Gwen Phillips, teaches the learner to draw…

  4. Pneumothorax in cardiac pacing

    DEFF Research Database (Denmark)

    Kirkfeldt, Rikke Esberg; Johansen, Jens Brock; Nohr, Ellen Aagaard;

    2012-01-01

    AIM: To identify risk factors for pneumothorax treated with a chest tube after cardiac pacing device implantation in a population-based cohort.METHODS AND RESULTS: A nationwide cohort study was performed based on data on 28 860 patients from the Danish Pacemaker Register, which included all Danish...... patients who received their first pacemaker (PM) or cardiac resynchronization device from 1997 to 2008. Multiple logistic regression was used to estimate adjusted odds ratios (aOR) with 95% confidence intervals for the association between risk factors and pneumothorax treated with a chest tube. The median...... age was 77 years (25th and 75th percentile: 69-84) and 55% were male (n = 15 785). A total of 190 patients (0.66%) were treated for pneumothorax, which was more often in women [aOR 1.9 (1.4-2.6)], and in patients with age >80 years [aOR 1.4 (1.0-1.9)], a prior history of chronic obstructive pulmonary...

  5. Leadership in cardiac surgery.

    Science.gov (United States)

    Rao, Christopher; Patel, Vanash; Ibrahim, Michael; Ahmed, Kamran; Wong, Kathie A; Darzi, Ara; von Segesser, Ludwig K; Athanasiou, Thanos

    2011-06-01

    Despite the efficacy of cardiac surgery, less invasive interventions with more uncertain long-term outcomes are increasingly challenging surgery as first-line treatment for several congenital, degenerative and ischemic cardiac diseases. The specialty must evolve if it is to ensure its future relevance. More importantly, it must evolve to ensure that future patients have access to treatments with proven long-term effectiveness. This cannot be achieved without dynamic leadership; however, our contention is that this is not enough. The demands of a modern surgical career and the importance of the task at hand are such that the serendipitous emergence of traditional charismatic leadership cannot be relied upon to deliver necessary change. We advocate systematic analysis and strategic leadership at a local, national and international level in four key areas: Clinical Care, Research, Education and Training, and Stakeholder Engagement. While we anticipate that exceptional individuals will continue to shape the future of our specialty, the creation of robust structures to deliver collective leadership in these key areas is of paramount importance.

  6. Predicting the onset of period-doubling bifurcations in noisy cardiac systems.

    Science.gov (United States)

    Quail, Thomas; Shrier, Alvin; Glass, Leon

    2015-07-28

    Biological, physical, and social systems often display qualitative changes in dynamics. Developing early warning signals to predict the onset of these transitions is an important goal. The current work is motivated by transitions of cardiac rhythms, where the appearance of alternating features in the timing of cardiac events is often a precursor to the initiation of serious cardiac arrhythmias. We treat embryonic chick cardiac cells with a potassium channel blocker, which leads to the initiation of alternating rhythms. We associate this transition with a mathematical instability, called a period-doubling bifurcation, in a model of the cardiac cells. Period-doubling bifurcations have been linked to the onset of abnormal alternating cardiac rhythms, which have been implicated in cardiac arrhythmias such as T-wave alternans and various tachycardias. Theory predicts that in the neighborhood of the transition, the system's dynamics slow down, leading to noise amplification and the manifestation of oscillations in the autocorrelation function. Examining the aggregates' interbeat intervals, we observe the oscillations in the autocorrelation function and noise amplification preceding the bifurcation. We analyze plots--termed return maps--that relate the current interbeat interval with the following interbeat interval. Based on these plots, we develop a quantitative measure using the slope of the return map to assess how close the system is to the bifurcation. Furthermore, the slope of the return map and the lag-1 autocorrelation coefficient are equal. Our results suggest that the slope and the lag-1 autocorrelation coefficient represent quantitative measures to predict the onset of abnormal alternating cardiac rhythms.

  7. Sudden cardiac death and inherited channelopathy: the basic electrophysiology of the myocyte and myocardium in ion channel disease.

    Science.gov (United States)

    Martin, Claire A; Matthews, Gareth D K; Huang, Christopher L-H

    2012-04-01

    Mutations involving cardiac ion channels result in abnormal action potential formation or propagation, leading to cardiac arrhythmias. Despite the large impact on society of sudden cardiac death resulting from such arrhythmias, understanding of the underlying cellular mechanism is poor and clinical risk stratification and treatment consequently limited. Basic research using molecular techniques, as well as animal models, has proved extremely useful in improving our knowledge of inherited arrhythmogenic syndromes. This offers the practitioner tools to accurately diagnose rare disorders and provides novel markers for risk assessment and a basis for new strategies of treatment.

  8. Significance of classifying antiarrhythmic actions since the cardiac arrhythmia suppression trial.

    Science.gov (United States)

    Vaughan Williams, E M

    1991-02-01

    The Cardiac Antiarrhythmic Suppression Trial (CAST) showed flecainide and encainide induced excess mortality compared with placebo. Labeling drugs as Class 1C is based on clinical observations, comprising measurements of the electrocardiographic parameters QRS. H-V and J-T intervals and of effective refractory period (ERP) as follows: 1--(QRS) wide, 2--(HV) long, 3--(ERP) unchanged, 4--(JT) unchanged. In vitro electrophysiology helped to explain the clinical findings. Flecainide and encainide rendered Na channels as nonconducting, but F and E were only slowly released from the channels after repolarization. At any given drug concentration, a proportion of total channels were eliminated, and the steady-state proportion increased at rising heart rate. It is not proven that the properties that lead to classification of a drug as 1C were those that caused excess deaths in the CAST. The proarrhythmic tendency of 1C drugs can be reduced by beta-blockade, and the mechanisms of adrenergic arrhythmogenicity are discussed. Propafenone is both a 1C drug and a beta-blocker, and its pharmacologic profile is reviewed to illustrate how it resembles and differs from flecainide and encainide. Some features of the CAST are assessed with particular reference to the extent to which conclusions drawn from the results may be justifiably extrapolated to other drugs classified as 1C.

  9. Clinical application of l-123 MlBG cardiac imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Do Young [College of Medicine, Donga Univ., Busan (Korea, Republic of)

    2004-10-01

    Cardiac neurotransmission imaging allows in vivo assessment of presynaptic reuptake, neurotransmitter storage and postsynaptic receptors. Among the various neurotransmitter, I-123 MlBG is most available and relatively well-established. Metaiodobenzylguanidine (MIBG) is an analogue of the false neurotransmitter guanethidine. It is taken up to adrenergic neurons by uptake-1 mechanism as same as norepinephrine. As tagged with I-123, it can be used to image sympathetic function in various organs including heart with planar or SPECT techniques. I-123 MIBG imaging has a unique advantage to evaluate myocardial neuronal activity in which the heart has no significant structural abnormality or even no functional derangement measured with other conventional examination. In patients with cardiomyopathy and heart failure, this imaging has most sensitive technique to predict prognosis and treatment response of betablocker or ACE inhibitor. In diabetic patients, it allow very early detection of autonomic neuropathy. In patients with dangerous arrhythmia such as ventricular tachycardia or fibrillation, MIBG imaging may be only an abnormal result among various exams. In patients with ischemic heart disease, sympathetic derangement may be used as the method of risk stratification. In heart transplanted patients, sympathetic reinnervation is well evaluated. Adriamycin-induced cardiotoxicity is detected earlier than ventricular dysfunction with sympathetic dysfunction. Neurodegenerative disorder such as Parkinson's disease or dementia with Lewy bodies has also cardiac sympathetic dysfunction. Noninvasive assessment of cardiac sympathetic nerve activity with l-123 MlBG imaging may be improve understanding of the pathophysiology of cardiac disease and make a contribution to predict survival and therapy efficacy.

  10. ABNORMAL CARDIOVASCULAR REFLEXES IN PATIENTS WITH ACHALASIA

    Institute of Scientific and Technical Information of China (English)

    戈峰; 李泽坚; 柯美云

    1994-01-01

    Using 3 non-invasive tests,abnormalities of cardiovascular reflex function were found in 7 of 15 patients with achalasia.Abnormalities of heart rate responses to the Valsalva maneuver,deep breathing ,and standing were moted in patients with autonomic neuropathy defect.The findings are consistent with the hypothesis that an abnormality of vagal function may contribute to the pathogenesis of achalasia.

  11. Relationship between labile plasma iron, liver iron concentration and cardiac response in a deferasirox monotherapy trial

    Science.gov (United States)

    Wood, John C.; Glynos, Tara; Thompson, Alexis; Giardina, Patricia; Harmatz, Paul; Kang, Barinder P.; Paley, Carole; Coates, Thomas D.

    2011-01-01

    The US04 trial was a multicenter, open-label, single arm trial of deferasirox monotherapy (30–40 mg/kg/day) for 18 months. Cardiac iron response was bimodal with improvements observed in patients with mild to moderate initial somatic iron stores; relationship of cardiac response to labile plasma iron is now presented. Labile plasma iron was measured at baseline, six months, and 12 months. In patients having a favorable cardiac response at 18 months, initial labile plasma iron was elevated in only 31% of patients at baseline and no patient at six or 12 months. Cardiac non-responders had elevated labile plasma iron in 50% of patients at baseline, 50% patients at six months, and 38% of patients at 12 months. Risk of abnormal labile plasma iron and cardiac response increased with initial liver iron concentration. Persistently increased labile plasma iron predicts cardiac non-response to deferasirox but labile plasma iron suppression does not guarantee favorable cardiac outcome. Study registered at www.clinicaltrials.gov (NCT00447694). PMID:21393329

  12. Semen abnormalities with SSRI antidepressants.

    Science.gov (United States)

    2015-01-01

    Despite decades of widespread use, the adverse effect profile of "selective" serotonin reuptake inhibitor (SSRI) antidepressants has still not been fully elucidated. Studies in male animals have shown delayed sexual development and reduced fertility. Three prospective cohort studies conducted in over one hundred patients exposed to an SSRI for periods ranging from 5 weeks to 24 months found altered semen param-eters after as little as 3 months of exposure: reduced sperm concentration, reduced sperm motility, a higher percentage of abnormal spermatozoa, and increased levels of sperm DNA fragmentation. One clinical trial showed growth retardation in children considered depressed who were exposed to SSRls. SSRls may have endocrine disrupting properties. Dapoxetine is a short-acting serotonin reuptake inhibitor that is chemically related to fluoxetine and marketed in the European Union for men complaining of premature ejaculation. But the corresponding European summary of product characteristics does not mention any effects on fertility. In practice, based on the data available as of mid-2014, the effects of SSRI exposure on male fertility are unclear. However, it is a risk that should be taken into account and pointed out to male patients who would like to father a child or who are experiencing fertility problems.

  13. [Renal abnormalities in ankylosing spondylitis].

    Science.gov (United States)

    Samia, Barbouch; Hazgui, Faiçal; Abdelghani, Khaoula Ben; Hamida, Fethi Ben; Goucha, Rym; Hedri, Hafedh; Taarit, Chokri Ben; Maiz, Hedi Ben; Kheder, Adel

    2012-07-01

    We will study the epidemiologic, clinical, biological, therapeutic, prognostic characteristics and predictive factors of development of nephropathy in ankylosing spondylitis patients. We retrospectively reviewed the medical record of 32 cases with renal involvement among 212 cases of ankylosing spondylitis followed in our service during the period spread out between 1978 and 2006. The renal involvement occurred in all patients a mean of 12 years after the clinical onset of the rheumatic disease. Thirty-two patients presented one or more signs of renal involvement: microscopic hematuria in 22 patients, proteinuria in 23 patients, nephrotic syndrome in 11 patients and decreased renal function in 24 patients (75%). Secondary renal amyloidosis (13 patients), which corresponds to a prevalence of 6,1% and tubulointerstitial nephropathy (7 patients) were the most common cause of renal involvement in ankylosing spondylitis followed by IgA nephropathy (4 patients). Seventeen patients evolved to the end stage renal disease after an average time of 29.8 ± 46 months. The average follow-up of the patients was 4,4 years. By comparing the 32 patients presenting a SPA and renal disease to 88 with SPA and without nephropathy, we detected the predictive factors of occurred of nephropathy: tobacco, intense inflammatory syndrome, sacroileite stage 3 or 4 and presence of column bamboo. The finding of 75% of the patients presented a renal failure at the time of the diagnosis of renal involvement suggests that evidence of renal abnormality involvement should be actively sought in this disease.

  14. Biochemical abnormalities in Pearson syndrome.

    Science.gov (United States)

    Crippa, Beatrice Letizia; Leon, Eyby; Calhoun, Amy; Lowichik, Amy; Pasquali, Marzia; Longo, Nicola

    2015-03-01

    Pearson marrow-pancreas syndrome is a multisystem mitochondrial disorder characterized by bone marrow failure and pancreatic insufficiency. Children who survive the severe bone marrow dysfunction in childhood develop Kearns-Sayre syndrome later in life. Here we report on four new cases with this condition and define their biochemical abnormalities. Three out of four patients presented with failure to thrive, with most of them having normal development and head size. All patients had evidence of bone marrow involvement that spontaneously improved in three out of four patients. Unique findings in our patients were acute pancreatitis (one out of four), renal Fanconi syndrome (present in all patients, but symptomatic only in one), and an unusual organic aciduria with 3-hydroxyisobutyric aciduria in one patient. Biochemical analysis indicated low levels of plasma citrulline and arginine, despite low-normal ammonia levels. Regression analysis indicated a significant correlation between each intermediate of the urea cycle and the next, except between ornithine and citrulline. This suggested that the reaction catalyzed by ornithine transcarbamylase (that converts ornithine to citrulline) might not be very efficient in patients with Pearson syndrome. In view of low-normal ammonia levels, we hypothesize that ammonia and carbamylphosphate could be diverted from the urea cycle to the synthesis of nucleotides in patients with Pearson syndrome and possibly other mitochondrial disorders.

  15. Hemostatic abnormalities in liver cirrhosis

    Directory of Open Access Journals (Sweden)

    Kendal YALÇIN

    2009-06-01

    Full Text Available In this study, 44 patients with liver cirrhosis were investigated for hemostatic parameters. Patients with spontaneous bacterial peritonitis, hepatocellular carcinoma, hepatorenal syndrome and cholestatic liver diseases were excluded. Patients were classified by Child-Pugh criterion and according to this 4 patients were in Class A, 20 in Class B and 20 in C. Regarding to these results, it was aimed to investigate the haematological disturbances in liver cirrhotic patients.In the result there was a correlation between activated partial thromboplastin time, serum iron, ferritin, transferrin, haptoglobin and Child-Pugh classification. Besides there was no correlation between prothrombin time, factor 8 and 9, protein C and S, anti-thrombin 3, fibrinogen, fibrin degradation products, serum iron binding capacity, hemoglobin, leukocyte, mean corpuscular volume and Child-Pugh classification.There were significant difference, in terms of AST, ferritin, haptoglobulin, sex and presence of ascites between groups (p0.05. In the summary, we have found correlation between hemostatic abnormalities and disease activity and clinical prognosis in patients with liver cirrhosis which is important in the management of these patients. This is also important for identification of liver transplant candidiates earlier.

  16. Kv4 potassium channel subunits control action potential repolarization and frequency-dependent broadening in rat hippocampal CA1 pyramidal neurones.

    Science.gov (United States)

    Kim, Jinhyun; Wei, Dong-Sheng; Hoffman, Dax A

    2005-11-15

    A-type potassium channels regulate neuronal firing frequency and the back-propagation of action potentials (APs) into dendrites of hippocampal CA1 pyramidal neurones. Recent molecular cloning studies have found several families of voltage-gated K(+) channel genes expressed in the mammalian brain. At present, information regarding the relationship between the protein products of these genes and the various neuronal functions performed by voltage-gated K(+) channels is lacking. Here we used a combination of molecular, electrophysiological and imaging techniques to show that one such gene, Kv4.2, controls AP half-width, frequency-dependent AP broadening and dendritic action potential propagation. Using a modified Sindbis virus, we expressed either the enhanced green fluorescence protein (EGFP)-tagged Kv4.2 or an EGFP-tagged dominant negative mutant of Kv4.2 (Kv4.2g(W362F)) in CA1 pyramidal neurones of organotypic slice cultures. Neurones expressing Kv4.2g(W362F) displayed broader action potentials with an increase in frequency-dependent AP broadening during a train compared with control neurones. In addition, Ca(2)(+) imaging of Kv4.2g(W362F) expressing dendrites revealed enhanced AP back-propagation compared to control neurones. Conversely, neurones expressing an increased A-type current through overexpression of Kv4.2 displayed narrower APs with less frequency dependent broadening and decreased dendritic propagation. These results point to Kv4.2 as the major contributor to the A-current in hippocampal CA1 neurones and suggest a prominent role for Kv4.2 in regulating AP shape and dendritic signalling. As Ca(2)(+) influx occurs primarily during AP repolarization, Kv4.2 activity can regulate cellular processes involving Ca(2)(+)-dependent second messenger cascades such as gene expression and synaptic plasticity.

  17. Cardiovascular adaptation and cardiac disease in the elite athlete.

    Science.gov (United States)

    Del Río-santiago, Valentín; Santiago Trinidad, Ricardo; Vicenty Rivera, Sonia

    2012-01-01

    Cardiovascular diseases are uncommon among trained athletes. Their occurrences mostly depend on the individual's age and fitness levels. Adequate understanding of the cardiovascular adaptations undergone by the competitive athletes' heart is of paramount importance in order to differentiate them from serious cardiovascular conditions. Diagnosing these abnormalities early may prevent rare but devastating potential complications associated with athletic activities and defines appropriate activity restrictions to minimize the risk of sudden cardiac death. This article will review concerns related to competitive athlete's cardiovascular adaptations and diseases, in light of specific recommendations presented in the 36th Bethesda Conference guidelines.

  18. Cardiac and skeletal muscle scintigraphy in dermato- and polymyositis: clinical implications

    Energy Technology Data Exchange (ETDEWEB)

    Buchpiguel, C.A. [Centro de Medicina Nuclear, Dept. de Radiologia, Faculdade de Medicina da USP, Sao Paulo, SP (Brazil); Roizemblatt, S. [Dept. of Rheumatology, Sao Paulo Univ. School of Medicine (Brazil); Pastor, E.H. [Dept. of Rheumatology, Sao Paulo Univ. School of Medicine (Brazil); Hironaka, F.H. [Centro de Medicina Nuclear, Dept. de Radiologia, Faculdade de Medicina da USP, Sao Paulo, SP (Brazil); Cossermelli, W. [Dept. of Rheumatology, Sao Paulo Univ. School of Medicine (Brazil)

    1996-02-01

    To determine the role of scintigraphy in the detection of skeletal and cardiac involvement in dermato- and polymyosits (DM/PM), we studied 30 patients with a confirmed diagnosis of DM/PM (23 females, 7 males; mean age: 35 years). Technetium-99m pyrophosphate ({sup 99m}Tc-DYP) and gallium-67 scans showed similar sensitivity, specificity and accuracy in the detection of skeletal muscle involvement when compared with serum enzymes (70%, 100% and 80%, respectively). Compared with the clinical parameters, {sup 99m}Tc-PYP showed 70% and {sup 67}Ga 65% accuracy. Abnormal PYP cardiac uptake was observed in 57% of patients, whereas abnormal {sup 67}Ga cardiac uptake was seen in only 15%. Electrocardiogrpahy was abnormal in 40%, rest gated blood pool study in 23%, and chest X-ray in 13%. In conclusion, both {sup 99m}Tc-PYP and {sup 67}Ga can be useful in the detection of the active phase of muscle disease. However, {sup 99m}Tc-PYP seems to be more effective than {sup 67}Ga in the early diagnosis of cardiac involvement. (orig.)

  19. Physics of Cardiac Arrhythmogenesis

    Science.gov (United States)

    Karma, Alain

    2013-04-01

    A normal heartbeat is orchestrated by the stable propagation of an excitation wave that produces an orderly contraction. In contrast, wave turbulence in the ventricles, clinically known as ventricular fibrillation (VF), stops the heart from pumping and is lethal without prompt defibrillation. I review experimental, computational, and theoretical studies that have shed light on complex dynamical phenomena linked to the initiation, maintenance, and control of wave turbulence. I first discuss advances made to understand the precursor state to a reentrant arrhythmia where the refractory period of cardiac tissue becomes spatiotemporally disordered; this is known as an arrhythmogenic tissue substrate. I describe observed patterns of transmembrane voltage and intracellular calcium signaling that can contribute to this substrate, and symmetry breaking instabilities to explain their formation. I then survey mechanisms of wave turbulence and discuss novel methods that exploit electrical pacing stimuli to control precursor patterns and low-energy pulsed electric fields to control turbulence.

  20. Platelets and cardiac arrhythmia

    Directory of Open Access Journals (Sweden)

    Jonas S De Jong

    2010-12-01

    Full Text Available Sudden cardiac death remains one of the most prevalent modes of death in industrialized countries, and myocardial ischemia due to thrombotic coronary occlusion is its primary cause. The role of platelets in the occurrence of SCD extends beyond coronary flow impairment by clot formation. Here we review the substances released by platelets during clot formation and their arrhythmic properties. Platelet products are released from three types of platelet granules: dense core granules, alpha-granules, and platelet lysosomes. The physiologic properties of dense granule products are of special interest as a potential source of arrhythmic substances. They are released readily upon activation and contain high concentrations of serotonin, histamine, purines, pyrimidines, and ions such as calcium and magnesium. Potential arrhythmic mechanisms of these substances, e.g. serotonin and high energy phosphates, include induction of coronary constriction, calcium overloading, and induction of delayed after-depolarizations. Alpha-granules produce thromboxanes and other arachidonic acid products with many potential arrhythmic effects mediated by interference with cardiac sodium, calcium and potassium channels. Alpha-granules also contain hundreds of proteins that could potentially serve as ligands to receptors on cardiomyocytes. Lysosomal products probably do not have an important arrhythmic effect. Platelet products and ischemia can induce coronary permeability, thereby enhancing interaction with surrounding cardiomyocytes. Antiplatelet therapy is known to improve survival after myocardial infarction. Although an important part of this effect results from prevention of coronary clot formation, there is evidence to suggest that antiplatelet therapy also induces anti-arrhythmic effects during ischemia by preventing the release of platelet activation products.

  1. Mediastinitis after cardiac transplantation

    Directory of Open Access Journals (Sweden)

    Noedir A. G. Stolf

    2000-05-01

    Full Text Available OBJECTIVE: Assessment of incidence and behavior of mediastinitis after cardiac transplantation. METHODS: From 1985 to 1999, 214 cardiac transplantations were performed, 12 (5.6% of the transplanted patients developed confirmed mediastinitis. Patient's ages ranged from 42 to 66 years (mean of 52.3±10.0 years and 10 (83.3% patients were males. Seven (58.3% patients showed sternal stability on palpation, 4 (33.3% patients had pleural empyema, and 2 (16.7% patients did not show purulent secretion draining through the wound. RESULTS: Staphylococcus aureus was the infectious agent identified in the wound secretion or in the mediastinum, or both, in 8 (66.7% patients. Staphylococcus epidermidis was identified in 2 (16.7% patients, Enterococcus faecalis in 1 (8.3% patient, and the cause of mediastinitis could not be determined in 1 (8.3% patient. Surgical treatment was performed on an emergency basis, and the extension of the débridement varied with local conditions. In 2 (16.7% patients, we chose to leave the surgical wound open and performed daily dressings with granulated sugar. Total sternal resection was performed in only 1 (8.3% patient. Out of this series, 5 (41.7% patients died, and the causes of death were related to the infection. Autopsy revealed persistence of mediastinitis in 1 (8.3% patient. CONCLUSION: Promptness in diagnosing mediastinitis and precocious surgical drainage have changed the natural evolution of this disease. Nevertheless, observance of the basic precepts of prophylaxis of infection is still the best way to treat mediastinitis.

  2. Magnetic Imaging of Applied and Propagating Action Currents in Cardiac Tissue Slices: Determination of Anisotropic Electrical Conductivities in a Two-Dimensional Bidomain.

    Science.gov (United States)

    Staton, Daniel Joseph

    We describe the first, high-resolution magnetic images of applied currents and propagating action currents in slices of canine cardiac tissue. This tissue was maintained in vitro at 37^circC. Our main conclusions are summarized as follows: the action currents produce magnetic fields which are measurable; during the initial stages of the propagating action potential, small, expanding, quatrefoil loops of current develop; the magnetic fields produced by repolarization currents are larger than previously anticipated. Most of the current associated with the propagating action potential is confined within the wavefront and should be magnetically silent; however, differences in the intracellular and extracellular electrical conductivities, in both the longitudinal and transverse fiber directions, are great enough that expanding quatrefoil current densities are associated with the wavefront and produce measurable magnetic fields. Since action currents are affected by the electrical conductivities, it is of interest to determine their values, which depend not only upon the tissue characteristics, but also on the mathematical model used to interpret the measured data. In our analysis of current injection, we use the anisotropic bidomain model which incorporates a passive, linear membrane. We introduce theoretical techniques to calculate the anisotropic conductivities of a two-dimensional bidomain. To apply these techniques to magnetic fields resulting from current injection into cardiac tissue slices, we need to improve the higher spatial frequency content of our present measurements. This may be done by measuring the magnetic field closer to the cardiac slice (presently 2.5 mm), decreasing the sampling interval of the measurement, and increasing the sampling area of the field. Magnetic fields are produced by propagating action currents, which are in turn the result of the propagating action potential. From the magnetic field, we directly image isochronal transmembrane

  3. Metoclopramide-induced cardiac arrest

    Directory of Open Access Journals (Sweden)

    Martha M. Rumore

    2011-11-01

    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

  4. Platelet enzyme abnormalities in leukemias

    Directory of Open Access Journals (Sweden)

    S Sharma

    2011-01-01

    Full Text Available Aim of the Study: The aim of this study was to evaluate platelet enzyme activity in cases of leukemia. Materials and Methods: Platelet enzymes glucose-6-phosphate dehydrogenase (G6PD, pyruvate kinase (PK and hexokinase (HK were studied in 47 patients of acute and chronic leukemia patients, 16 patients with acute myeloid leukemia (AML(13 relapse, three in remission, 12 patients with acute lymphocytic leukemia (ALL (five in relapse, seven in remission, 19 patients with chronic myeloid leukemia (CML. Results: The platelet G6PD activity was significantly low in cases of AML, ALL and also in CML. G6PD activity was normalized during AML remission. G6PD activity, although persistently low during ALL remission, increased significantly to near-normal during remission (P < 0.05 as compared with relapse (P < 0.01. Platelet PK activity was high during AML relapse (P < 0.05, which was normalized during remission. Platelet HK however was found to be decreased during all remission (P < 0.05. There was a significant positive correlation between G6PD and PK in cases of AML (P < 0.001 but not in ALL and CML. G6PD activity did not correlate with HK activity in any of the leukemic groups. A significant positive correlation was however seen between PK and HK activity in cases of ALL remission (P < 0.01 and CML (P < 0.05. Conclusions: Both red cell and platelet enzymes were studied in 36 leukemic patients and there was no statistically significant correlation between red cell and platelet enzymes. Platelet enzyme defect in leukemias suggests the inherent abnormality in megakaryopoiesis and would explain the functional platelet defects in leukemias.

  5. Crude oil exposures reveal roles for intracellular calcium cycling in haddock craniofacial and cardiac development

    Science.gov (United States)

    Sørhus, Elin; Incardona, John P.; Karlsen, Ørjan; Linbo, Tiffany; Sørensen, Lisbet; Nordtug, Trond; van der Meeren, Terje; Thorsen, Anders; Thorbjørnsen, Maja; Jentoft, Sissel; Edvardsen, Rolf B.; Meier, Sonnich

    2016-08-01

    Recent studies have shown that crude oil exposure affects cardiac development in fish by disrupting excitation-contraction (EC) coupling. We previously found that eggs of Atlantic haddock (Melanogrammus aeglefinus) bind dispersed oil droplets, potentially leading to more profound toxic effects from uptake of polycyclic aromatic hydrocarbons (PAHs). Using lower concentrations of dispersed crude oil (0.7-7 μg/L ∑PAH), here we exposed a broader range of developmental stages over both short and prolonged durations. We quantified effects on cardiac function and morphogenesis, characterized novel craniofacial defects, and examined the expression of genes encoding potential targets underlying cardiac and craniofacial defects. Because of oil droplet binding, a 24-hr exposure was sufficient to create severe cardiac and craniofacial abnormalities. The specific nature of the craniofacial abnormalities suggests that crude oil may target common craniofacial and cardiac precursor cells either directly or indirectly by affecting ion channels and intracellular calcium in particular. Furthermore, down-regulation of genes encoding specific components of the EC coupling machinery suggests that crude oil disrupts excitation-transcription coupling or normal feedback regulation of ion channels blocked by PAHs. These data support a unifying hypothesis whereby depletion of intracellular calcium pools by crude oil-derived PAHs disrupts several pathways critical for organogenesis in fish.

  6. Epigenetic regulation in cardiac fibrosis

    Institute of Scientific and Technical Information of China (English)

    Li-Ming; Yu; Yong; Xu

    2015-01-01

    Cardiac fibrosis represents an adoptive response in the heart exposed to various stress cues. While resolution of the fibrogenic response heralds normalization of heart function, persistent fibrogenesis is usually associated with progressive loss of heart function and eventually heart failure. Cardiac fibrosis is regulated by a myriad of factors that converge on the transcription of genes encoding extracellular matrix proteins, a process the epigenetic machinery plays a pivotal role. In this minireview, we summarize recent advances regarding the epigenetic regulation of cardiac fibrosis focusing on the role of histone and DNA modifications and non-coding RNAs.

  7. Cardiac Involvement in Ankylosing Spondylitis

    Science.gov (United States)

    Ozkan, Yasemin

    2016-01-01

    Ankylosing spondylitis is one of the subgroup of diseases called “seronegative spondyloarthropathy”. Frequently, it affects the vertebral colon and sacroiliac joint primarily and affects the peripheral joints less often. This chronic, inflammatory and rheumatic disease can also affect the extraarticular regions of the body. The extraarticular affections can be ophthalmologic, cardiac, pulmonary or neurologic. The cardiac affection can be 2-10% in all patients. Cardiac complications such as left ventricular dysfunction, aortitis, aortic regurgitation, pericarditis and cardiomegaly are reviewed. PMID:27222669

  8. Acupuncture therapy related cardiac injury.

    Science.gov (United States)

    Li, Xue-feng; Wang, Xian

    2013-12-01

    Cardiac injury is the most serious adverse event in acupuncture therapy. The causes include needling chest points near the heart, the cardiac enlargement and pericardial effusion that will enlarge the projected area on the body surface and make the proper depth of needling shorter, and the incorrect needling method of the points. Therefore, acupuncture practitioners must be familiar with the points of the heart projected area on the chest and the correct needling methods in order to reduce the risk of acupuncture therapy related cardiac injury.

  9. Abnormal heart rate recovery and chronotropic incompetence on exercise in chronic obstructive pulmonary disease.

    Science.gov (United States)

    Gupta, Mansi; Bansal, Vishal; Chhabra, Sunil K

    2013-08-01

    Chronotropic incompetence (CI; failure to reach the targeted heart rate (HR) on exercise) and a delayed HR recovery (HRR; ≤12 beats decline within the first minute after cessation) reflect autonomic dysfunction (AD) and predict adverse cardiac prognosis. As chronic obstructive pulmonary disease (COPD) is known to be associated with AD, we hypothesized that these patients may manifest these responses on exercise. The prevalence and predictors of these responses in COPD and their association with its severity have not been evaluated. Normoxemic, stable male patients with COPD (n = 39) and 11 healthy controls underwent lung function testing and incremental leg ergometry. HR responses were monitored during exercise and recovery to compute the HRR and CI. Of all the patients, 33 (84.6%) had at least one of the two exercise responses as abnormal, with the majority (23, 58.9%) having both an abnormal HRR and CI. The frequency of abnormal responses increased with increasing Global Initiative for Chronic Obstructive Lung Disease stage and body mass index, airflow obstruction, dyspnoea and exercise capacity index. After adjusting for smoking history and post-bronchodilator forced expiratory volume in 1 second, only a reduced diffusion capacity for carbon monoxide predicted abnormal HRR, though weakly. We concluded that abnormal HRR and CI are common in patients with COPD. These responses are observed with increasing frequency as the severity of disease increases.

  10. Structural and functional cardiac changes in myotonic dystrophy type 1: a cardiovascular magnetic resonance study

    Directory of Open Access Journals (Sweden)

    Hermans Mieke CE

    2012-07-01

    Full Text Available Abstract Background Myotonic dystrophy type 1 (MD1 is a neuromuscular disorder with potential involvement of the heart and increased risk of sudden death. Considering the importance of cardiomyopathy as a predictor of prognosis, we aimed to systematically evaluate and describe structural and functional cardiac alterations in patients with MD1. Methods Eighty MD1 patients underwent physical examination, electrocardiography (ECG, echocardiography and cardiovascular magnetic resonance (CMR. Blood samples were taken for determination of NT-proBNP plasma levels and CTG repeat length. Results Functional and structural abnormalities were detected in 35 patients (44%. Left ventricular systolic dysfunction was found in 20 cases, left ventricular dilatation in 7 patients, and left ventricular hypertrophy in 6 patients. Myocardial fibrosis was seen in 10 patients (12.5%. In general, patients had low left ventricular mass indexes. Right ventricular involvement was uncommon and only seen together with left ventricular abnormalities. Functional or structural cardiac involvement was associated with age (p = 0.04, male gender (p Conclusions CMR can be useful to detect early structural and functional myocardial abnormalities in patients with MD1. Myocardial involvement is strongly associated with conduction abnormalities, but a normal ECG does not exclude myocardial alterations. These findings lend support to the hypothesis that MD1 patients have a complex cardiac phenotype, including both myocardial and conduction system alteration.

  11. Normal cardiac function in mice with supraphysiological cardiac creatine levels.

    Science.gov (United States)

    Santacruz, Lucia; Hernandez, Alejandro; Nienaber, Jeffrey; Mishra, Rajashree; Pinilla, Miguel; Burchette, James; Mao, Lan; Rockman, Howard A; Jacobs, Danny O

    2014-02-01

    Creatine and phosphocreatine levels are decreased in heart failure, and reductions in myocellular phosphocreatine levels predict the severity of the disease and portend adverse outcomes. Previous studies of transgenic mouse models with increased creatine content higher than two times baseline showed the development of heart failure and shortened lifespan. Given phosphocreatine's role in buffering ATP content, we tested the hypothesis whether elevated cardiac creatine content would alter cardiac function under normal physiological conditions. Here, we report the creation of transgenic mice that overexpress the human creatine transporter (CrT) in cardiac muscle under the control of the α-myosin heavy chain promoter. Cardiac transgene expression was quantified by qRT-PCR, and human CrT protein expression was documented on Western blots and immunohistochemistry using a specific anti-CrT antibody. High-energy phosphate metabolites and cardiac function were measured in transgenic animals and compared with age-matched, wild-type controls. Adult transgenic animals showed increases of 5.7- and 4.7-fold in the content of creatine and free ADP, respectively. Phosphocreatine and ATP levels were two times as high in young transgenic animals but declined to control levels by the time the animals reached 8 wk of age. Transgenic mice appeared to be healthy and had normal life spans. Cardiac morphometry, conscious echocardiography, and pressure-volume loop studies demonstrated mild hypertrophy but normal function. Based on our characterization of the human CrT protein expression, creatine and phosphocreatine content, and cardiac morphometry and function, these transgenic mice provide an in vivo model for examining the therapeutic value of elevated creatine content for cardiac pathologies.

  12. Nail abnormalities in patients with vitiligo*

    Science.gov (United States)

    Topal, Ilteris Oguz; Gungor, Sule; Kocaturk, Ozgur Emek; Duman, Hatice; Durmuscan, Mustafa

    2016-01-01

    Background Vitiligo is an acquired pigmentary skin disorder affecting 0.1-4% of the general population. The nails may be affected in patients with an autoimmune disease such as psoriasis, and in those with alopecia areata. It has been suggested that nail abnormalities should be apparent in vitiligo patients. Objective We sought to document the frequency and clinical presentation of nail abnormalities in vitiligo patients compared to healthy volunteers. We also examined the correlations between nail abnormalities and various clinical parameters. Methods This study included 100 vitiligo patients and 100 healthy subjects. Full medical histories were collected from the subjects, who underwent thorough general and nail examinations. All nail changes were noted. In the event of clinical suspicion of a fungal infection, additional mycological investigations were performed. Results Nail abnormalities were more prevalent in the patients (78%) than in the controls (55%) (p=0.001). Longitudinal ridging was the most common finding (42%), followed by (in descending order): leukonychia, an absent lunula, onycholysis, nail bed pallor, onychomycosis, splinter hemorrhage and nail plate thinning. The frequency of longitudinal ridging was significantly higher in patients than in controls (p<0.001). Conclusions Nail abnormalities were more prevalent in vitiligo patients than in controls. Systematic examination of the nails in such patients is useful because nail abnormalities are frequent. However, the causes of such abnormalities require further study. Longitudinal ridging and leukonychia were the most common abnormalities observed in this study. PMID:27579738

  13. An Abnormal Psychology Community Based Interview Assignment

    Science.gov (United States)

    White, Geoffry D.

    1977-01-01

    A course option in abnormal psychology involves students in interviewing and observing the activities of individuals in the off-campus community who are concerned with some aspect of abnormal psychology. The technique generates student interest in the field when they interview people about topics such as drug abuse, transsexualism, and abuse of…

  14. Abnormal Event Detection Using Local Sparse Representation

    DEFF Research Database (Denmark)

    Ren, Huamin; Moeslund, Thomas B.

    2014-01-01

    measurement based on the difference between the normal space and local space. Specifically, we provide a reasonable normal bases through repeated K spectral clustering. Then for each testing feature we first use temporal neighbors to form a local space. An abnormal event is found if any abnormal feature...

  15. An Abnormal Vibrational Mode of Torsion Pendulum

    Institute of Scientific and Technical Information of China (English)

    赵亮; 涂英; 顾邦明; 胡忠坤; 罗俊

    2003-01-01

    In the experiment for the determination of the gravitational constant G, we found an abnormal vibrational mode of the torsion pendulum. The abnormal mode disappeared as a magnetic damper was introduced to the torsion pendulum system. Our experimental results also show that the magnetic damper can be used to suppress the high frequency vibrational noises to torsion pendulums effectively.

  16. Abnormal Raman spectral phenomenon of silicon nanowires

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The Raman spectra of two one-dimensional silicon nanowire samples with different excitation wavelengths were measured and an abnormal phenomenon was discovered that the Raman spectral features change with the wavelengths of excitation. Closer analysis of the crystalline structure of samples and the changes in Raman spectral features showed that the abnormal behavior is the result of resonance Raman scattering selection effect.

  17. Use of cardiac biomarkers in neonatology.

    Science.gov (United States)

    Vijlbrief, Daniel C; Benders, Manon J N L; Kemperman, Hans; van Bel, Frank; de Vries, Willem B

    2012-10-01

    Cardiac biomarkers are used to identify cardiac disease in term and preterm infants. This review discusses the roles of natriuretic peptides and cardiac troponins. Natriuretic peptide levels are elevated during atrial strain (atrial natriuretic peptide (ANP)) or ventricular strain (B-type natriuretic peptide (BNP)). These markers correspond well with cardiac function and can be used to identify cardiac disease. Cardiac troponins are used to assess cardiomyocyte compromise. Affected cardiomyocytes release troponin into the bloodstream, resulting in elevated levels of cardiac troponin. Cardiac biomarkers are being increasingly incorporated into clinical trials as indicators of myocardial strain. Furthermore, cardiac biomarkers can possibly be used to guide therapy and improve outcome. Natriuretic peptides and cardiac troponins are potential tools in the diagnosis and treatment of neonatal disease that is complicated by circulatory compromise. However, clear reference ranges need to be set and validation needs to be carried out in a population of interest.

  18. Hemodynamic consequences of cardiac malformations in two juvenile ball pythons (Python regius).

    Science.gov (United States)

    Jensen, Bjarke; Wang, Tobias

    2009-12-01

    Two cases of bifid ventricles and cardiac malformations in juvenile ball python (Python regius) were investigated by blood pressure measurements and macro- and microscopic sectioning. A study of a normal ball python was included for reference. In both cases, all cardiac chambers were enlarged and abnormally shaped. Internal assessment of the ventricles revealed a pronounced defect of the muscular ridge, which normally is responsible for separating the systemic and pulmonary circuits. Consistent with the small muscular ridge, systolic pressures were identical in the pulmonary and systemic arteries, but, the snakes, nevertheless, lived to reach body weights severalfold of their hatchling weight.

  19. Recent developments in cardiac pacing.

    Science.gov (United States)

    Rodak, D J

    1995-10-01

    Indications for cardiac pacing continue to expand. Pacing to improve functional capacity, which is now common, relies on careful patient selection and technical improvements, such as complex software algorithms and diagnostic capabilities.

  20. Robotic Applications in Cardiac Surgery

    Directory of Open Access Journals (Sweden)

    Alan P. Kypson

    2008-11-01

    Full Text Available Traditionally, cardiac surgery has been performed through a median sternotomy, which allows the surgeon generous access to the heart and surrounding great vessels. As a paradigm shift in the size and location of incisions occurs in cardiac surgery, new methods have been developed to allow the surgeon the same amount of dexterity and accessibility to the heart in confined spaces and in a less invasive manner. Initially, long instruments without pivot points were used, however, more recent robotic telemanipulation systems have been applied that allow for improved dexterity, enabling the surgeon to perform cardiac surgery from a distance not previously possible. In this rapidly evolving field, we review the recent history and clinical results of using robotics in cardiac surgery.