Impact of left bundle branch block on heart failure with reduced ejection fraction symptoms and outcomes: Experience of a Moroccan centre

• Published in: Archives of Cardiovascular Diseases Supplements Vol. 13; no. 2; pp. 215 - 216
• Main Authors: Mechal, H., El Moussaid, M., Boutaleb, A., Mounaouir, K., Haboub, M., Habbal, R.
• Format: Journal Article
• Language: English
• Published: Elsevier Masson SAS 01.05.2021
• ISSN: 1878-6480
• DOI: 10.1016/j.acvdsp.2021.04.165

Left bundle branch block (LBBB) occurs in up to 30% of patients with heart failure (HF). The detrimental effect of LBBB on left ventricular systolic and diastolic function caused by regional delays of electrical activity leads to dyssynchronous left ventricular function and has been established in HF patients. Some studies have reported LBBB as an independent predictor of mortality in HF patients. To study the impact of LBBB on heart failure with reduced ejection fraction (HFrEF) symptoms and outcomes. Transversal retrospective study conducted between May 2006 and June 2019 including all patients beyond the age of 14 with HFrEF, followed-up in the therapeutic unit of HF of our department. We studied 2 groups of patients: group 1 with complete LBBB and group 2 without complete LBBB. We compared clinical, echocardiographic and prognostic features. We collected 3412 patients. Six hundred and ninety-three patients (20.31%) in group1 and 2719 patients (79.69%) in group 2. Male gender was represented in 63 versus 63.7 years (P=0.857). Mean age was 68.82±12.47 years versus 64.79±12.88 years (P<0.001). Regarding etiologies: ischemic heart disease in 50.1% versus 59.4%, dilated cardiomyopathy in 9.3%vs5.9%, valvular heart disease in 3% versus 3.8%, chemotherapy induced cardiomyopathy in 2.8% versus 2.1% (P<0.001). Class IV NYHA in 3.8% vs. 1.9% (P<0.001). Echocardiographic features: LVEDD was 61.29±9.24mm versus 57.06±8.99mm (P<0.001), mean LVEF was 32.24±13.15% versus 35.87±12.98% (P=0.022), elevated left ventricle filling pressures in 29.4% versus 21.6% (P<0.001), severe secondary mitral regurgitation in 9.6% vs. 5.8% (P<0.001). Hospitalization for HF rate in 22.7% vs. 16.5% (P<0.001). LBBB patients are more symptomatic, have lower LVEF, more severe secondary mitral regurgitation, higher hospitalization rate and higher mortality rate. These results are important to consider in order to justify the importance of cardiac resynchronization therapy.