863Leadless endocardial pacing improves symptoms in patients with failed conventional CRT implant in long term follow up

Funding Acknowledgements EBR Systems, Inc OnBehalf WiSE-CRT and LV-SELECT study and POST-M REGISTRY Background The WiSE-CRT (Wireless stimulation endocardial) system has advantages over conventional epicardial CRT. Whenever conventional CRT failed to implant or failed to echocardiographic response, the WiSE-CRT was implanted as part of the WiSE CRT study (N = 13), as part of the LV-SELECT study (N = 35) or as part of the POST-M REGISTRY (N = 117) over the last 8 years. All these studies have reported high rates of clinical and echocardiographic response compared to conventional CRT. Objectives The purpose of this analysis was to determine the safety and clinical response in the largest available number of implanted patients (pts) with long term follow up of 2 years and the first, second and third generation of WiSE-CRT devices. Method All pts undergoing a WiSE-CRT implantation as part of the WiSE CRT study (N = 13), as part of the LV-SELECT study (N = 35) or as part of the POST-M REGISTRY (N = 117) were analysed (N = 165). Pts were followed-up for 24 months and considered CRT responders if an improvement in NYHA ≥ 1 class from baseline (pre-implant) was achieved. Results In total, 165 pts were implanted, demographics include: 68.2 ± 9.6 year’s old, 81.8% male, 49.7% with history of AFib and 54.5% non-ischaemic aetiology. The mean intrinsic QRS duration was 165.0 ± 32.3 msec (28 pts pace-maker dependent). 161 pts had the system successfully implanted with no major complications, 3 (1.8%) pts developed a pericardial effusion and 1 (0.6%) electrode was lost during implantation and recovered surgically. During the 24-month follow-up period, 20 (12.1%) pts died from any cause, 4 (2.4%) pts developed TIA or Stroke and 15 (9.1%) pts had pocket or transmitter infection. There was a significant improvement in NYHA functional class in 63.6% pts and an average improvement of -26.1 (-45.1, -7.1) msec in QRS duration. Conclusion Despite a history of failed conventional CRT implantation, pts undergoing CRT upgrades with a WiSE-CRT have a high success rate and a complication rate similar to previously described. In addition endocardial LV pacing led to symptomatic improvements in 64% of patients reaching the 24 month of follow up. Abstract Figure 1: Forest Plot NYHA Responder Rat