Left bundle branch block in Duchenne muscular dystrophy: Prevalence, genetic relationship and prognosis.

• Main Authors: Abdallah Fayssoil, Rabah Ben Yaou, Adam Ogna, Cendrine Chaffaut, France Leturcq, Olivier Nardi, Karim Wahbi, Denis Duboc, Frederic Lofaso, Helene Prigent, Bernard Clair, Pascal Crenn, Guillaume Nicolas, Pascal Laforet, Anthony Behin, Sylvie Chevret, David Orlikowski, Djillali Annane
• Format: Article
• Language: English
• Published: Public Library of Science (PLoS) 2018-01-01
• Series: PLoS ONE
• Online Access: http://europepmc.org/articles/PMC5755816?pdf=render

Duchenne muscular dystrophy (DMD) is an inherited myogenic disorder due to mutations in the dystrophin gene on chromosome Xp21.1. We designed this study to determine the prevalence of left bundle branch block (LBBB), whether there is a relationship between LBBB and genetic pattern, and to assess predictive factors for acute cardiac events and mortality in adult DMD patients.We reviewed the charts of DMD followed at the Home Mechanical Ventilation Unit of the Raymond Poincare University Hospital.A total of 121 patients, aged from 18 to 41 years have been included in our study. Median vital capacity (VC) was 12% [7; 19.5] of predicted. Almost all patients were on home mechanical ventilation (95%). LBBB was present in 15 patients (13%); among them, 10 disclosed exonic deletions. After a median follow up of 6 years, 21 patients (17%) experienced acute heart failure (AHF), 7 patients (6%) supraventricular arrhythmia, 3 patients (2.4%) ventricular tachycardia, 4 patients (3%) significant electrical disturbances. LBBB was significantly associated with cardiac events (OR = 12.7; 95%CI [3.78-42.7]; p <0.0001) and mortality (OR = 4.4; 95%CI [1.44-13.7]; p 0.009). Presence of residual dystrophin protein was not associated with significant less cardiac events. Age and LVEF were also predictive factors for cardiac events and mortality.LBBB is relatively frequent in DMD and is a major predictive factor for cardiac events and mortality. Presence of residual dystrophin protein was not associated with a lower incidence of cardiac events.