Topic summary
Cardiac pacemaker
Extracted from the Wikipedia article Natural pacemaker.
Ectopic pacemaker
An ectopic pacemaker also known as an ectopic focus or ectopic foci, is a group of excitable cells that causes a premature heart beat outside the normally functioning SA node of the heart. It is thus a cardiac pacemaker that is ectopic, producing an ectopic beat. If chronic this can result in arhythmias such as tachycardia, bradycardia, or ventricular fibrillation. An artificial pacemaker may be used to counter this.