Tracking the path traversed by temporary pacing lead

Persistent left superior vena cava (PLSVC) results from abnormal development of the sinus venosus in the early stages of fetal life. Though there are numerous reports of successful permanent pacemaker implants in such cases, placement of permanent pacing leads in such cases is technically challenging, often requiring shaping of stylets and considerable lead maneuvering. We describe an interesting case wherein a temporary pacemaker lead after entering the PLSVC followed an unusual fluoroscopic course with demonstrable pacing in right ventricle (RV), right atrium (RA) and the left ventricle (LV). Interventional cardiologists and intensivists performing pacing procedures need to be aware that one may rarely encounter such interesting radiographic and electrocardiographic patterns in these cases with anomalous systemic venous drainage.