premature contraction and brody effect

human body anatomy electrocardiogram electrocardiogram education recording heart heartbeat wave qrs segment interval duration amplitude heart rate left atrium right ventricle interventricular septum rhythm cardiology sinoatrial node atrioventricular bundle bundle branch purkinje fibers electrodes monitoring sinus ventricular premature contractions brody effect diastolic volume phase systolic muscle cavity blood flow conductivity gas radial conduction tangential conduction myocardial physical effects electrical effects