secundum atrial septal defect

ecg monitoring ekg education cardiac arrhythmia congenital heart disease atrial septal defect notch fragmented qrs wave right ventricular dilatation hypertrophy human body anatomy electrocardiogram electrocardiogram recording heart heartbeat segment interval duration amplitude rate left atrium ventricle interventricular septum rhythm cardiology sinoatrial node atrioventricular bundle bundle branch purkinje fibers electrodes sinus muscle cavity blood flow conductivity gas myocardial