Lying down with a very heavy heartbeat and not being able to sleep may have organic heart disease, such as ischemic heart disease, arrhythmia, and cardiomyopathy. Ischemic heart disease may have the clinical manifestation of a very heavy heartbeat, but it is not very typical. Patients with arrhythmias often have palpitations. There are many kinds of arrhythmias, such as atrial premature beats, ventricular premature beats, atrial tachycardia, ventricular tachycardia, sinus bradycardia, atrioventricular block, paroxysmal supraventricular tachycardia, atrial fibrillation, etc. Tachyarrhythmias are more likely, and further electrocardiogram or 24-hour ambulatory cardiogram is needed to clarify the diagnosis. In addition, viral myocarditis, hypertrophic cardiomyopathy, etc. may also cause palpitations. In addition to heart disease, thyroid disorders such as hyperthyroidism can also cause palpitations.