Coronary sinus dissection during left ventricular pacing electrode implantation.

Coronary sinus (CS) dissection during biventricular pacing electrode implantation is a complication that rarely develops. A 71-year-old female with recurrent ventricular tachycardia, heart decompensation, and poor left ventricular function because of dilated cardiomyopathy was admitted for the implantation of a cardioverter-defibrillator for biventricular pacing. During the operation, we experienced a CS dissection with hematoma in the left ventricle wall while introducing the guidance catheter into the CS. However, the pacing lead was successfully implanted into the posterolateral vein using the "over-the-wire" technique. The postoperative electrocardiogram showed a decreased QRS; meanwhile, the echocardiography revealed dimensional reduction and functional improvement of the left ventricle.