How to upgrade a leadless pacemaker to cardiac resynchronization therapy.

INTRODUCTION: We sought to develop an efficient method to upgrade pacing-induced cardiomyopathy (PICM) patients from a leadless pacemaker (LPM) to cardiac resynchronization therapy. METHODS AND RESULTS: Three consecutive patients with chronic atrial fibrillation, implanted with an LPM, with permanent right ventricular pacing, and who developed left ventricular systolic dysfunction due to PICM, were included. A conventional biventricular pacemaker with two different coronary sinus leads, one used for left lateral ventricular pacing, one for early right ventricular sensing, was implanted. It was then synchronized with the LPM working as the right ventricular pacing lead to provide biventricular pacing. The upgrading technique was feasible in all cases, without any perioperative complication. All patients had an improved clinical status during follow-up. CONCLUSION: This new upgrading technique allows efficient cardiac resynchronization therapy in LPM patients while preventing tricuspid valve crossing and providing an increased battery longevity.