Management of Phrenic Stimulation in CRT Patients over the Long Term: Still an Unmet Need ?

Background: Phrenic stimulation (PS) may cause intolerable symptoms and prevent CRT delivery in 2–5% of patients. We sought to ensure effective cardiac resynchronization therapy (CRT) delivery by management of PS at the left ventricular (LV) target site. Methods and Results : Two hundred and eleven consecutive patients received a CRT device despite PS occurrence at the LV target site at implantation, when a PS‐LV difference >2V was achieved by LV stimulation programming (cathode, pacing vector). PS management strategy both at implantation and at follow‐up (FU) aimed to keep the target LV implantation site. LV reverse remodeling was assessed by echocardiography before implantation and at follow‐up. LV lead placement was lateral/posterolateral in all the 211 patients; 51 of 211 had detectable PS at FU, 26 of 211 (12.3%) were symptomatic. Symptoms occurred more frequently when PS‐LV difference was 3V is achieved. Further improvement in lead manufacturing and pacing electronics are awaited to meet this clinical need. (PACE 2011; 34:1201–1208)