Long-term experience with coronary sinus side branch stenting to stabilize left ventricular electrode position

BACKGROUND Despite technical advancements, implantation of coronary sinus (CS) leads may be challenging, and dislocation remains a relevant clinical problem. OBJECTIVE The aim of this study was to investigate the effectiveness, safety, and long-term outcome of stent implantation to anchor the lead to the wall of the CS side branch. METHODS Stenting of a CS side branch was performed in 312 patients. The procedure was performed because of postoperative lead dislocation in 16 patients and because of an intraoperative unstable lead position or phrenic nerve stimulation in 296 cases. A bare metal coronary stent was introduced over a second guide wire in the same CS sheath. The stent was deposited 5-35 mm proximal to the most proximal electrode. Mechanical damage of the CS side branch or pericardial effusion was not observed owing to stenting. RESULTS During follow-up (median 28.4, interquartile range 15-37, maximum 70 months), a clinically important increase in the left ventricular pacing threshold was found in four cases and reoperation was necessary in only two patients (0.6%). Phrenic nerve stimulation was observed in 18 instances, and repositioning with an ablation catheter was performed in seven cases. Impedance measurements did not suggest lead insulation failure. Three stented leads were extracted without complication after 3-49 months owing to infection, while four leads were extracted easily during heart transplantation after 7-27 months. CONCLUSION Stent implantation to stabilize CS lead position seems to be an effective and safe procedure in prevention and treatment of CS lead dislocation in selected cases.