What is an indication for the use of an external cardiac pacemaker?

The use of an external cardiac pacemaker is indicated in situations where there is a need to stimulate the heart directly due to a significant disruption in its normal electrical activity. Symptomatic complete heart block, or third-degree AV block, occurs when there is a complete failure of electrical conduction between the atria and ventricles. This condition can lead to symptoms such as dizziness, fatigue, or even syncope due to the heart's inefficacy in pumping blood adequately.

When a patient experiences symptomatic complete heart block, immediate pacing can help restore an effective heart rate and rhythm, thereby alleviating symptoms and preventing further complications. The external pacemaker provides temporary pacing until a more permanent solution, such as a permanent pacemaker insertion, can be arranged if indicated.

Other conditions listed, while serious, may not necessitate the immediate use of an external pacemaker in the same way. For example, while asystole is a critical situation, it often requires advanced cardiac life support and is more often treated with defibrillation rather than pacing. Ventricular tachycardia may sometimes be managed with medications or cardioversion. Atrial flutter typically involves a different approach that may include rate control or rhythm conversion rather than immediate pacing. Thus, the context of symptomatic