Left ventricular pacing with a temporary pacemaker: Case report.

We report a case of temporary pacemaker lead malposition in the left ventricle crossing the interventricular septum (IVS). The majority of described cases occur due to a patent foramen ovale and are frequently incidental findings. A course across the IVS is rarely found and this complication with temporary leads is not even reported in the literature. This very rare location entails a risk of dangerous complications associated with left-to-right flow after lead removal. Echocardiography was an essential tool to diagnose the lead's course inside the heart and enabled secure removal of the lead with cardiac surgery backup.