reference range of r wave amplitude and s wave amplitude for normal chinese

human body anatomical ecg education recording heart heartbeat qrs wave segment duration amplitude heart rate left ventricle right interventricular septum rhythm cardiology electrocardiography sinoatrial node atrioventricular bundle bundle branch purkinje fibers electrodes monitoring gender age race body type graph electrode electrocardiograph theory cardiovascular medicine cardiogram cardiac anatomy beat cardiac depolarization diagnosis disease ekg electrocardiogram ventricle