[Implantation of a pacemaker and superior vena cava anomalies: value of peroperative angiocardiography].

Rare abnormalities of systemic venous return may be encountered during the implantation of endocardiac pacemakers such as persistent left superior vena cava. Our patient, a 66 year old female, had, primary cardiomyopathy with sinus node dysfunction, left bundle branch block and a cardiothoracic ratio of 0,70. After left subclavian venous puncture the catheter seemed to advance down the left border of the cardiac shadow and a false route was suggested? Angiocardiography was performed immediately and showed a double superior caval system and allowed identification of the right ventricular apex. The electrode was positioned via a left SVC, coronary sinus, right atrium, right ventricle trajectory. Control angiocardiography was performed 1 year later and showed both the left SVC and coronary sinus to be still patent. The follow-up period is now 20 months. There have been 13 other reports of implantation using the left SVC; they include 4 short term failures, one late failure at 23 months, and one fatality after 2 months due to massive thrombosis of the coronary sinus. Seven good results were confirmed with follow-up of 3 to 16 months. The use of "tined" ventricular electrodes reduces the risk of secondary electrode displacement.