What is the most common indication for the placement of a pacemaker?

The most common indication for the placement of a pacemaker is sick sinus syndrome. Sick sinus syndrome encompasses a range of conditions characterized by abnormal heart rhythms originating from the sinoatrial node, leading to irregular heartbeats that can be too slow, and in some cases, result in periods of bradycardia. This condition often necessitates the use of a pacemaker to maintain a regular heart rate and rhythm, particularly in symptomatic patients who experience fatigue, lightheadedness, or syncope due to inadequate heart rates.

Bradycardia, while a main feature of sick sinus syndrome, is a broader term that can arise from various causes, including medications, increased vagal tone, or pathology elsewhere in the conduction system. Therefore, sick sinus syndrome is the more specific diagnosis leading to pacemaker placement. Heart failure may require a pacemaker, but typically in the context of specific rhythm issues or as part of cardiac resynchronization therapy. Intermittent tachycardia does not usually mandate a pacemaker; rather, it might require antiarrhythmic treatment or other interventions. Thus, sick sinus syndrome remains the primary and most common reason for the indication of pacemaker implantation.