Optimizing Cardiac Resynchronization Therapy in Heart Failure Patients With Prolonged QRS Duration: Insights Into Electrical and Mechanical Dyssynchrony

Heart failure (HF) represents a critical stage of cardiac disease, associated with high morbidity and mortality. Cardiac resynchronization therapy (CRT) has become a pivotal treatment for HF patients with prolonged QRS duration. This therapy employs a biventricular pacing system to correct cardiac electromechanical dyssynchrony, thereby improving cardiac function, symptoms, and prognosis. Numerous clinical trials have consistently highlighted the benefits of CRT in this subgroup, leading to its unanimous recommendation in clinical practice guidelines. However, a significant proportion of patients do not achieve an adequate therapeutic response, despite adherence to these guidelines. As CRT treats patients by correcting cardiac electromechanical dyssynchrony, assessing electrical and mechanical dyssynchrony is crucial in candidate selection. This review explores the evidence, recent clinical practice guidelines, and insight into electrical and mechanical dyssynchrony to optimize CRT candidate selection in HF patients with prolonged QRS duration.