Palpitation (palpitation) is a conscious heartbeat and panic, often accompanied by discomfort in the precordial region. The causes of palpitation are: (1) rapid or slow heart rate; (2) arrhythmia; (3) increased myocardial contractility; and (4) increased neurosensitivity. (1) History: 1. The urgency of onset, duration, persistence or paroxysm. 2. 2. The presence or absence of fever, whether it is regular, fast or slow, and whether it is neat. 3. The relationship with labor, emotional excitement, poor sleep, etc. 4. Any difficulty in breathing, inability to lie down, little urination, swelling, etc. 5. Any hyperphagia, fear of heat, easy sweating, wasting, etc. 6. Any application of ephedrine, anticholinergics, cocaine, insulin and other drugs. 7. History of heart disease and hyperthyroidism. 8. Any family history of cardiac arrhythmia and sudden death. (B) Physical examination 1. Pay attention to whether the heart is enlarged, whether there are pathological murmurs, heart rate and heart rhythm. 2. Measure blood pressure and the presence of vascular murmurs. Pay attention to the carotid artery pulsation. 3. Pay attention to whether the thyroid gland is enlarged, whether there is proptosis, tremor and murmur. 4. Any signs of anemia. (C) Other tests: The following tests are optional according to the condition 1. 2. Do cardiac x-ray examination. 3. Electrocardiogram and, if necessary, echocardiography, Holter and cardiac electrophysiological examination. 4. Check blood TSH, T 3, T 4, rT 3, and 131 I absorption test if necessary. 5. Check urine VMA (vanillylmandelic acid), blood norepinephrine, epinephrine, renin, angiotensin II, aldosterone if necessary. 6. Check blood potassium, sodium, chloride and magnesium. 7. Abdominal ultrasound examination of kidney, adrenal gland and pancreas. Differential diagnosis】 (a) Slow heart rate and rhythm: common in sinus bradycardia, third degree AV block, atrial flutter with 4:1 AV block, ventricular autonomic rhythm, etc. (2) Fast heart rate with rhythm: common in supraventricular and ventricular paroxysmal tachycardia, atrial flutter, sinus tachycardia, etc. (3) Slow heart rate with arrhythmia: common in sinus arrhythmia, sinus block, sinus quiescence, junctional escape, second degree type I AV block, and slow heart rate atrial fibrillation. (iv) Fast heart rate with irregular rhythm: Commonly seen in atrial fibrillation, multi-source atrial tachycardia, sinus tachycardia with prophase contraction, irregular atrial flutter. (E) Organic heart disease should be excluded from all kinds of arrhythmias, children and adolescents with palpitations should be noted except for supraventricular or ventricular tachycardia, such as pre-excitation syndrome and long QT or short QT syndrome, etc. (E) Sudden onset and cessation are seen in paroxysmal tachycardia. Persistent cases are commonly seen in hyperthyroidism, anemia, and neurosis. (f) Syncope, syncope precursor or vertigo, seen in persistent or non-persistent ventricular tachycardia, pre-excitation syndrome with atrial fibrillation, atrial fibrillation or atrial flutter with rapid ventricular rate, supraventricular tachycardia with vasovagal syncope, etc. (g) With impaired consciousness, seen in A-S syndrome. (viii) With peripheral circulatory disturbance, which is seen in various types of shock. (ix) With respiratory distress and inability to lie down, commonly seen in heart failure. (j) Sweating, commonly associated with hyperthyroidism, hypoglycemia, and pheochromocytoma. (xi) With pallor, weakness, dizziness, and dark eyes, commonly due to various types of anemia and hemorrhage. (xii) Palpitations appearing in quiet conditions and suppressed during activity, with no obvious findings on objective examination but with neurological symptoms, are seen in cardiac neurosis.