Heart failure (HF) affects more than 64 million individuals worldwide, and 20% to 30% of patients with HF and systolic dysfunction have cardiac dyssynchrony due to conduction system disease. JAMA Review author Mihail Chelu, MD, PhD, of Baylor College of Medicine discusses cardiac resynchronization therapy with JAMA Associate Editor David Simel, MD, MHS. Related Content:

• Cardiac Resynchronization Therapy
• Leadless Ultrasound-Based Cardiac Resynchronization System in Heart Failure