St. Michael's implants about 290 defibrillators and 230 pacemakers a year.

What is the difference between a pacemaker and an implanted defibrillator?

A pacemaker is about one-quarter the size of a defibrillator. It monitors your heart rhythm - which slows with age and certain medications - and sends electrical pulses to your heart if it is beating too slow or you miss a heartbeat.

A defibrillator is a small, battery-powered device that treats a dangerous fast heart rhythm by delivering a jolt of electricity to the heart. They are typically implanted in patients who have or are at risk for developing ventricular tachycardia or ventricular fibrillation, two types of very fast and life-threatening heart rhythms that originate from the ventricles, the lower chambers of the heart.

Source: St. Michael's Hospital