Background: Left ventricular (LV) pacing with resynchronization therapy improves ventricular synchrony in patients with decreased LV function and Left Bundle Branch Bock (LBBB). Objective: The goal of this study is to show that LV pacing is superior to BiVentricular (BiV) pacing in patients with ventricular dysfunction and LBBB. Methods: This is a retrospective study from 2 hospitals’ registries in Lebanon. 121 patients with LVEF ≤ 35%, a QRS ≥130msec and a LBBB pattern on full medical therapy were included in 2 groups: LV pacing and BiV pacing. All patients had echocardiograms before and after device implantation. The primary endpoint was the change in ejection fraction and the secondary endpoints were decrease in pulmonary artery pressure (PAPs), in LV end diastolic diameter (LVDD) and in LV end systolic diameter (LVSD). Statistical analysis was done with SPSS. Results: The study population was mostly males (69.4%) with ischemic cardiomyopathy 74 (61.2%) & a mean age of 67 years old. Fifty (41,3%) patients were programmed as LV pacing. A statistically significant improvement in EF was seen in the LV only 9.2% compared to BiV pacing 5.5%. Similarly, we noticed a significant decrease in the LVDD and LVSD in the LV pacing compared to the second group. There was a trend in favor of more PAPs improvement in the LV pacing that did not reach significance. Conclusion: This study demonstrates that LV pacing significantly improves EF and LV size compared to BiV pacing. A large multicenter trial is needed to confirm our findings.