Unusual pacemaker lead placement in an unsuspecting heart.

During the implantation process, the pacemaker leads advanced easily into the atrium and ventricle from the left subclavian vein. On fl uoroscopy, the locations of the leads in the atrium and ventricle appeared atypical (Fig. 1). An intraoperative transthoracic echocardiography was then performed, showing the atrial lead into the left atrium (Fig. 2). The pacemaker leads were then repositioned into the right heart chambers, but the procedure was quite diffi cult because the leads preferentially entered into the left heart chambers.