Heart Failure with Reduced Ejection Fraction and Left Bundle Branch Block in a Moroccan Center

Background: Some studies have reported left bundle branch block as an independent predictor of outcome in heart failure with reduced ejection fraction patients. The aim of this study is to compare clinical, echocardiographic and prognostic features of heart failure with reduced ejection fraction patients with and without complete left bundle branch block. Results: We collected 3412 patients. 693 patients (20.31%) in group 1 and 2719 patients (79.69%) in group 2. The underlying structural heart disease was ischemic heart disease in 50.1% versus 59.4%, dilated cardiomyopathy in 9.3% versus 5.9%, valvular heart disease in 3% versus 3.8%, chemotherapy induced cardiomyopathy in 2.8% versus 2.1% (p<0.001). Class I New York Heart Association in 9.3% versus 16.2%, class II in 59.8% versus 61.2%, class III in 27.1% versus 20.7%, class IV in 3.8% versus 1.9% (p<0.001). Echocardiographic features: Left ventricular end-diastolic diameter was 61.29±9.24mm versus 57.06±8.99mm (p<0.001), mean left ventricular ejection fraction was 32.24±13.15% versus 35.87±12.98% (p=0.022), elevated left ventricular filling pressures in 29.4% versus 21.6% (p<0.001), severe secondary mitral regurgitation in 9.6% versus 5.8% (p<0.001). Hospitalization for HF rate in 22.7% versus 16.5% (p<0.001). Conclusions: Patients with LBBB are more symptomatic, have lower left ventricular ejection fraction, more severe secondary mitral regurgitation, higher hospitalization for heart failure rate. These results are important to consider in order to justify the importance of cardiac resynchronization therapy in Moroccan heart failure patients with reduced ejection fraction.