Which device delivers a controlled electrical shock to reset heart rhythm?

• A. Defibrillator
• B. Pacemaker
• C. Stethoscope
• D. ECG machine

Answer: (A)

Defibrillators are designed to deliver a controlled electric shock to the heart to stop the current abnormal rhythm and allow the heart’s natural electrical system to restart a normal rhythm. This is crucial in life-threatening situations like ventricular fibrillation, where the heart quivers instead of pumping effectively. A pacemaker, by contrast, provides small electrical pulses to keep the heart beating regularly but does not deliver a resetting shock. A stethoscope is used to listen to heart sounds, not to affect rhythm. An ECG machine records the heart’s electrical activity over time to diagnose rhythm problems, but it doesn’t treat them with a shock.