Rescue-stenting of an occluded lateral coronary sinus branch for recanalization after dissection during cardiac resynchronization device implantation.

Cardiac resynchronization therapy (CRT) using left- (LV) or biventricular pacing is widely applied in selected heart failure patients. However, transvenous LV-lead placement into coronary sinus (CS) branches can be challenging. A 77-year-old female patient with New York Heart Association class III symptoms due to dilated cardiomyopathy [LV ejection fraction (LVEF): 10%, QRS-duration: 150 ms], despite optimal medical treatment presented for CRT. Coronary sinus angiograms were performed after transvenous CS cannulation. Within a large posterolateral vein, low phrenic nerve stimulation thresholds were found. The only alternative smaller tortuous lateral branch showed a significant narrowing, making LV-lead advancement impossible. Angioplasty was performed, using a venoplasty balloon. This caused complete branch occlusion. After recanalization of the vessel by implantation of a bare metal stent, the lead could be advanced through the stent. Optimal pacing parameters without phrenic nerve stimulation were established. Angioplasty of CS branches during CRT implantation procedures bears the risk of complete branch occlusion, but recanalization can acutely be achieved by stent implantation. This is the first report on rescue-stenting of a CS branch after angioplasty-related occlusion. Transthoracic lead implantation, accompanied risks, and slower recovery could thus be avoided.