premature ventricular contraction

premature ventricular contraction Contraction of the lower chambers of the heart, the ventricles, that occurs earlier than usual because of abnormal electrical activity of the ventricles. Abbreviated PVC. The premature contraction is followed by a pause as the heart’s electrical system resets itself; the contraction following the pause is usually more forceful than normal. These more forceful contractions are frequently perceived as palpitations.