Premature beats can be heard with a stethoscope. The characteristics of premature beats auscultation are mainly the sudden appearance of an early heartbeat on the basis of a regular heartbeat, followed by a relatively longer than normal heartbeat gap, and then the continuation of the regular heartbeat. Premature beats are common cardiac arrhythmias. Patients with premature beats can be asymptomatic or have symptoms such as chest tightness and panic. Clinically, premature beats are classified as atrial premature beats, ventricular premature beats and junctional premature beats. Premature beats can be seen in physiological states or in disease states. In the physiological state, premature contractions are often caused by triggers, such as exertion, emotional stress, drinking strong tea, or heavy smoking. In the pathological state, premature beats are most often caused by organic cardiovascular diseases such as coronary heart disease, hypertensive heart disease, myocarditis, cardiomyopathy and rheumatic heart disease.