What device is implanted for prevention of sudden cardiac death in high-risk patients?

• A. Pacemaker
• B. Implantable cardioverter-defibrillator (ICD)
• C. External defibrillator
• D. Cardiac resynchronization therapy device

Answer: (B)

The device used to prevent sudden cardiac death in high-risk patients is an implanted cardioverter-defibrillator. It continuously monitors the heart, detects life-threatening fast rhythms such as ventricular tachycardia or ventricular fibrillation, and automatically delivers therapy to restore a normal rhythm. This therapy can be antitachycardia pacing to interrupt a fast rhythm or a high-energy shock for more dangerous pauses, reducing the chance of fatal arrhythmias. Pacemakers mainly provide pacing to maintain heart rate and aren’t designed to terminate VT/VF. External defibrillators are used outside the body and are not implanted. Cardiac resynchronization therapy devices help coordinate the heart’s pumping in certain heart failure patients and may include defibrillation capability in some configurations, but for the specific goal of preventing sudden cardiac death in high-risk individuals, the implanted cardioverter-defibrillator is the standard choice.