Several studies emphasize the utility of dynamical heart rate parameters and/or repolarization disparity in the assessment of malignant arrhythmia vulnerability. In this study the spatio-temporal action potential dynamics were assessed by the use of body surface potential map (BSPM) records. Healthy subjects and a group of arrhythmia patients were enrolled in the study. Records were taken with ...

ramadan fasting is one of the most important religious duties of muslims, that its effect on the heart has not been determined yet. our objective was to evaluate the effect of ramadan fasting on ventricular repolarization as assessed by qt interval, corrected qt interval, qt dispersion or corrected qt dispersion. sixthy healthy subjects aged 20 to 35 years were dispersion included in this study...

Action potential duration and contractility are reduced following premature excitations, and gradually increase as the stimulus interval is lengthened. To examine these phenomena of electrical and mechanical restitution in the human heart, we simultaneously measured action potential duration and the maximum rate of left ventricular pressure in five patients undergoing electrophysiological study...

BACKGROUND Obstetricians regard maternal age of 20 to 35 years as the optimal age for pregnancy. Adolescent pregnancy and pregnancy at the ages of 35 years and above are associated with higher risks. Pregnancy is pro-arrhythmic and rarely precipitates ventricular arrhythmias. OBJECTIVES QT dispersion is an index of heterogeneity of ventricular repolarization and a predictor of propensity of v...

Repolarization abnormalities, including those induced by the congenital or acquired long QT (LQT) syndrome, provide a substrate for life-threatening cardiac arrhythmias. In this article, we use computational biology to link HERG mutations mechanistically to the resulting abnormalities of the whole-cell action potential. We study how the kinetic properties of I(Ks) (the slow delayed rectifier) t...

Does APD Gradient Indicate Dispersion of Repolarization ? To the Editor: The article by Glukhov et al1 is a very important study, providing, as it does, direct measurement of action potential durations (APD) transmurally in the human heart. We commend the authors for providing the first evidence for M cells in the human heart. However, we dispute the assumption throughout the article that APD g...