Objective:To investigate the effect of ventricular septal scars on the capture of left bundle branch during left bundle branch area pacing by cardiac magnetic resonance. Methods:52 patients who were intended to receive left bundle branch area pacing were retrospectively analyzed. According to whether the capture of left bundle branch was achieved, the groups were divided into the failure group and the success group. We estimate the scores of ventricular septal scar by cardiac magnetic resonance according to different segments. Results:The score of the upper ventricular septal scar is an independent predictor of the success of the left bundle branch. When the scar of the upper ventricular septum is less than 25%, the success rate of the capture of the left bundle branch is 100%. When the scar is equal to or more than 50%, the failure rate is 100%. Conclusion:Upper ventricular septal scars presented by cardiac magnetic resonance imaging can predict the success of LBBP, providing a reliable reference for the smooth implementation of left bundle branch area pacing in clinical practice.