Pacemaker Syndrome

Introduction to Pacemaker Syndrome

Pacemaker syndrome is a clinical condition characterized by symptoms resulting from the loss of normal atrioventricular (AV) synchrony, most commonly occurring in patients with ventricular-based pacing (VVI mode), which can significantly impact quality of life in patients with cardiac pacemakers 1
The American College of Cardiology notes that pacemaker syndrome represents an important cause of morbidity 1

Patients with pacemaker syndrome may experience symptoms such as light-headedness or syncope, fatigue, chest discomfort, dyspnea, cough, confusion, and presyncope due to adverse hemodynamics caused by the loss of AV synchrony and occurrence of ventriculoatrial conduction or atrial contraction against closed AV valves 2
The syndrome includes episodic alternating AV synchrony and asynchrony, inadequate cardiac output associated with ventriculoatrial (VA) conduction, and patient awareness of beat-to-beat variations due to absence of AV synchrony or fixed asynchrony in cardiac contractile sequence 1
Hemodynamic disturbances manifest through several mechanisms, including cannon A waves, V waves transmitted to the atria or pulmonary veins, and bundle branch block patterns of ventricular contraction with paced beats 1

The American College of Cardiology recommends that for sinus node dysfunction, atrial-based pacing (AAI or DDD) is preferred to maintain proper AV synchrony 1, 2
For AV block, dual-chamber pacing (DDD) is recommended to maintain proper AV synchrony 1
Reprogramming to dual-chamber pacing (DDD) mode can significantly improve quality of life in patients with VVI pacing who develop pacemaker syndrome 2