Chest Pain and Diaphragmatic Pacing after Pacemaker Implantation

A 42-year-old woman with recurrent neurocardiogenic syncope underwent implantation of a dual-chamber pacemaker with active fixation leads; there were no apparent complications. Three weeks later, she reported having sharp pain in the left anterior chest wall. A chest radiograph and echocardiogram taken at that time revealed satisfactory lead placement and no evidence of pericardial effusion. Three months after implantation, the patient began to experience diaphragmatic pacing. Evaluation of the pacemaker revealed an absence of ventricular capture or sensing. Another chest radiograph revealed that the ventricular lead tip had changed position (Fig. 1). A computed tomographic scan showed the tip of the right ventricular pacemaker lead in the anterior aspect of the lower lobe of the left lung (Fig. 2). There was no pneumothorax or pericardial effusion, although focal thickening was noted where the lead traversed the pericardium. Repair was performed with the patient under general anesthesia and with use of transesophageal echocardiographic guidance. The helix at the end of the pacemaker lead was retracted, and the right ventricular lead was removed. A replacement lead was placed in the right ventricular apex without complications. A follow-up chest radiograph revealed a small left apical and a lateral pneumothorax, which later resolved. A follow-up echocardiogram showed no evidence of pericardial effusion.

Fig. 1 A chest radiograph shows 2 pacemaker leads. One lead terminates as expected in the right atrium, while the 2nd lead projects beyond the right ventricular wall.

Fig. 2 Multiplanar reconstruction of a chest computed tomographic scan in an oblique axial projection shows the distal pacemaker lead passing through the anteroinferior aspect of the right ventricular wall, with the tip in the anterior aspect of the lower lobe of the left lung.

Comment

Although the mechanism of pacemaker lead perforation (as in the present case) or migration is not clear, there are 2 likely explanations. Pressure may be exerted on the small tip of the lead either by torque or by the force of the contraction associated with each heart beat. In general, large-tipped leads are less likely than small-tipped leads to migrate or perforate.