Long-term follow-up after pacemaker implantation via persistent left superior vena cava.

BACKGROUND The persistent left superior vena cava (PLSVC) is a relatively common con-genital venous return anomaly. It may have serious clinical implications especially in case of pacemaker/cardioverter-defibrillator implantation, venous catheter insertion, radio-frequency ablation and cardiac surgery. There is also some evidence that PLSVC may be accompanied by arrhythmias. The aim of this report is to present the effectiveness and safety of cardiac pacing via PLSVC, clinical outcome and appearance of arrhythmias in a long-term follow-up. METHODS AND RESULTS Four cases of pacing electrodes implanted via PLSVC in patients without any other cardiac congenital heart anomalies were observed for at least 6 years. There was 1 patient with AAI, 2 patients with VVI, and 1 with DDD pacemaker. Atrial electrodes were implanted on the free right atrial wall, 2 ventricular electrodes were implanted in right ventricular outflow tract, 1 in postero-lateral cardiac vein. During the mean 110 months of observation, pacing was efficient. One patient underwent an upgrade from AAI to biatrial pac-ing due to progressive interatrial conduction delay during the follow-up. No other intervention or pacemaker related events were noticed except for battery replacement. CONCLUSIONS The presence of PSVC may complicate implantation, but it does not influence the long-term follow-up of pacing parameters.