What is the difference between a permanent pacemaker and an implantable cardioverter-defibrillator? Can you see a purpose for a combination device?

What will be an ideal response?

A permanent pacemaker is used to correct the pace of the heart in patients with a consistent, ongoing arrhythmia (typically a bradycardia). An implantable cardioverter-defibrillator (ICD) is used to prevent sudden cardiac death caused by rare, episodic, lethal arrhythmias. An ICD monitors the heart rhythm and fires an electrical impulse when it senses fibrillation or tachycardia. Patients with ongoing dysthymias who are also at risk of sudden cardiac death from fibrillation would benefit from a combination device.