Cardiac resynchronization therapy for patients with left bundle branch block

Abstract

Introduction. Left bundle branch block (LBBB) is an electrocardiographic abnormality detected in patients whose conduction through the left fascicle of the His-Purkinje system is either delayed or blocked. Even though in otherwise healthy people, LBBB doesn’t cause significant concern, in patients presenting with acute chest pain, reduced ejection fraction or heart failure, LBBB has a great impact, affecting prognosis and life expectancy. Currently, there are no guidelines for the treatment of LBBB, with the exception of those who have developed heart failure, severe systolic dysfunction of the left ventricle and need cardiac resynchronization therapy (CRT). CRT has been proven to reduce hospitalization and all-cause mortality in such patients. Aim of the study. This study aims to determine the necessity of CRT throughout the patients with LBBB and heart failure with reduced left ventricular ejection fraction and to highlight the criteria for CRT selection. Methods and materials. The retrospective cross-sectional study was based on 105 case histories analysis of patients admitted between 2019-2021 with complete LBBB in the Department of Cardiology, of the Sfânta Treime Municipal Hospital during the years 2019-2021. Results. Out of the 105 patients with LBBB, 74 of them have been subjected to an echocardiogram. All of them had either a sinus rhythm (86.486%) or atrial fibrillation (13.513%). 52.69% had been diagnosed with class III and IV (NYHA) heart failure and 13.513% had a reduced left ventricular ejection fraction (LVEF) below 35%. Respectively 13.513% out of the patients with LBBB, LVEF below 35%, class III and IV heart failure (NYHA) and sinus rhythm or atrial fibrillation would have been eligible and would have benefited from CRT. Conclusion. CRT reduces hospitalization and all-cause mortality, improving long-term survival of patients with LBBB who also match the other eligibility criteria.