Septal Venous Channel Perforation during Left Bundle Branch Area Pacing: A Prospective Study

Objectives To characterize the diagnosis, frequency, and procedural implications of septal venous channel perforation during left bundle branch area pacing (LBBAP). Methods All consecutive patients undergoing LBBAP over an 8-month period were prospectively studied. During lead placement, obligatory septal contrast injection was performed twice, at initiation (implant entry zone) and completion (fixation zone). An intuitive fluoroscopic schema using orthogonal views (LAO/RAO) and familiar landmarks is described. Using this, we resolved zonal distribution (I-VI) of lead position on the ventricular septum and its angulation (post-fixation angle θ). Subjects with/without septal venous channel perforation were compared. Results Sixty-one-patients [Male 57.3%, Median Age (IQR) 69.5(62.5-74.5) years] were enrolled. Septal venous channel perforation was observed in 8 (13.1%) patients [Male 28.5%, Median Age (IQR) 64(50-75) years]. They had higher frequency of, i) right-sided-implant (25% vs. 1.9%, p = 0.04), ii) fixation in zone III at the mid-superior septum (75% vs 28.3%, p = 0.04), iii) steeper angle of fixation- median θ (IQR) [19(10-30)° vs. 5(4-19)°, p = 0.01), and iv) longer median penetrated-lead-length (IQR) [13(10-14.8) vs. 10(8.5-12.5)mm, p = 0.03]. Coronary sinus drainage of contrast was noted in 5 (62.5%) patients. Abnormal impedance drops during implantation (12.5% vs. 5.7%, p = NS) were not significantly different. Conclusion When evaluated systematically, septal venous channel perforation may be encountered commonly after LBBAP. The fiducial reference framework described using fluoroscopic imaging identified salient associated findings. This may be addressed with lead repositioning to a more inferior location and are not associated with adverse consequence acutely or in early follow-up.