Internal medicine

Heart failure

Ejection fraction

QRS complex

Cardiology

Surgery

Fluoroscopy

Bundle branch block

Left bundle branch block

Cardiac resynchronization therapy

Electrocardiography

Medicine

Heart Rhythm

Cardiac resynchronization therapy (CRT) based on the conventional biventricular pacing (BiV-CRT) technique sometimes results in broad QRS complex and suboptimal response.

Left bundle branch–optimized cardiac resynchronization therapy (LOT-CRT): Results from an international LBBAP collaborative study group