A heart beat due to an impulse generated somewhere in the heart outside the sinoatrial node. Ectopic beats are generally premature in timing; they are classified as supraventricular if they originate in the atria and ventricular if they arise from a focus in the ventricles. They may be produced by any heart disease, by nicotine from smoking, or by caffeine from excessive tea or coffee consumption; they are common in normal individuals. The patient may be unaware of their presence or may feel that his heart has missed a beat. Ectopic beats may be suppressed by drugs such as quinidine, propranolol, and lignocaine; avoidance of smoking and reduction in excessive tea or coffee intake may help.
A heart muscle contraction that is outside the normal sequence of the cardiac cycle. The impulse is generated outside the usual focus of the sinoatrial node. Also known as extrasystoles, ectopic beats are called ventricular if they arise from a focus in the ventricles and supraventricular if they arise in the atria. They may cause no symptoms and the affected subject may be unaware of them. The beat may, however, be the result of heart disease or may be caused by nicotine or caffeine. If persistent, the individual may suffer from irregular rhythm or ventricular fibrillation and need treatment with anti-arrhythmic drugs.
An electrical impulse that begins at any place in the heart other than the sinoatrial node.