Beware of Venous Anomalies in Young Patients with Sick Sinus Syndrome: A Report of Two Cases of Sick Sinus Syndrome with Systemic Venous Anomalies.

We report two young patients with symptomatic sick sinus syndrome admitted for permanent pacemaker implantation (PPI). On evaluation with echocardiography, one of them was found to have persistent left superior vena cava and venography showed absent right superior vena cava also. He underwent PPI with leads inserted via left superior vena cava, coronary sinus, right atrium and right ventricle. The other patient was incidentally found to have interrupted inferior vena cava with azygos continuation while being planned for temporary pacemaker implantation. She underwent successful PPI. We would like to stress the importance of having a high suspicion for these systemic venous anomalies in patients presenting with sick sinus syndrome especially at young age. If we could diagnose preoperatively, we can avoid on table surprises.