Implantable cardioverter defibrillator

In medicine and cardiology, an implantable cardioverter defibrillators (ICD) are "implantable devices which continuously monitor the electrical activity of the heart and automatically detect and terminate ventricular tachycardia and ventricular fibrillation. They consist of an impulse generator, batteries, and electrodes."

Implantable cardioverter-defibrillators can reduce mortality in patients who have heart failure with an ejection fraction of less than 35%.