idea photo arrhythmias and heart diseases related to disorders of normal heart rhythm. model red heart lies on top of the roll of

adult arrhythmia background bradycardia card cardiology checkup child concept diagnosis diagnostics disease disorder ecg ekg electrical electrocardiogram examination fibrillation heart heartbeat idea impulse irregular man model normal palpitation paper pattern photo problem pulse quivering rate red rhythm roll shape sign slow sport symptom tachycardia test top trace trial white woman