Predicting response to cardiac resynchronization therapy: Use of strict left bundle branch block criteria

• Published in: Pacing and clinical electrophysiology 2019-04, Vol.42 (4), p.431-438
• Main Authors: Hadjis, Alexios, AlTurki, Ahmed, Proietti, Riccardo, Montemezzo, Mauricio, Bernier, Martin, Joza, Jacqueline, Hadjis, Tomy, Essebag, Vidal
• Format: Article
• Language: English
• Subjects: Aged; Bundle-Branch Block - physiopathology; Cardiac Resynchronization Therapy; Congestive heart failure; Electrocardiography; Female; Heart Failure - physiopathology; Heart Failure - therapy; Humans; left bundle branch block; Male; Morbidity; Morphology; Mortality; QRS duration; Stroke Volume; Ventricle; Ventricular Dysfunction, Left - physiopathology; Ventricular Dysfunction, Left - therapy
• ISSN: 0147-8389; 1540-8159
• DOI: 10.1111/pace.13638

Background Cardiac resynchronization therapy (CRT) reduces morbidity and mortality in heart failure with reduced ejection fraction (HFrEF). CRT efficacy is greater in left bundle branch block (LBBB). This study aimed to determine if strict LBBB criteria predict an improved QRS duration and left ventricular ejection fraction (LVEF) response after CRT. Methods HFrEF patients who received a CRT device at a single quaternary center were included. Patients were divided into three groups based on baseline QRS morphology. Group 1 consisted of patients with strict LBBB. Group 2 had conventional LBBB, and group 3 had non‐LBBB morphology. Outcomes assessed included change in QRS duration after CRT, change in LVEF, and all‐cause mortality. Results In 231 patients, 56% of patients were in group 1, 29% were in group 2, and 15% were in group 3. Patients with strict LBBB had a significant reduction in QRS duration (–20.9 ± 12.4 ms) compared to conventional LBBB (6.7 ± 19.4 ms; P