In a dual-chamber pacemaker, what is the purpose of having two leads?

In a dual-chamber pacemaker, what is the purpose of having two leads?

• A. To sense and coordinate activity between the right atrium and right ventricle
• B. To pace both atrium and ventricle independently without coordination
• C. To provide defibrillation therapy
• D. To deliver pharmacologic therapy

Answer: (A)

The main idea is to coordinate atrial and ventricular activity by sensing in the atrium and pacing both chambers to preserve AV synchrony. With a lead in the right atrium and one in the right ventricle, the device can sense when the atrium activates and then time a ventricular paced beat accordingly, maintaining a proper atrioventricular delay. This improves cardiac output and symptoms by keeping the heart’s chambers working in concert. The alternative of pacing both chambers independently without coordination would disrupt timing, and defibrillation or drug delivery is not the function of a standard dual-chamber pacemaker.

The main idea is to coordinate atrial and ventricular activity by sensing in the atrium and pacing both chambers to preserve AV synchrony. With a lead in the right atrium and one in the right ventricle, the device can sense when the atrium activates and then time a ventricular paced beat accordingly, maintaining a proper atrioventricular delay. This improves cardiac output and symptoms by keeping the heart’s chambers working in concert. The alternative of pacing both chambers independently without coordination would disrupt timing, and defibrillation or drug delivery is not the function of a standard dual-chamber pacemaker.