P5680One-year outcomes of heart failure patients undergoing cardiac resynchronization therapy using adaptivCRT algorithm

Abstract Background Adaptive cardiac resynchronization therapy (aCRT) algorithm provides synchronized left ventricular (LV) only pacing and ambulatory optimization of the intrinsic atrioventricular and interventricular conduction intervals. Studies reporting morbidity and mortality outcomes of aCRT carriers in daily clinical practice are lacking. Purpose To determine in a real-life setting, whether 1-year outcomes were different among CRT carriers undergoing aCRT pacing and those under conventional biventricular (biV) pacing. Methods Symptomatic heart failure (HF) patients with sinus rhythm undergoing first CRT-defibrillator implant were selected from the UMBRELLA nationwide registry (2012–2017). The primary endpoint was the composite of all-cause mortality or HF hospitalization at 12-month follow-up. HF admission was defined as hospitalization due to symptoms requiring intravenous diuretic treatment. Primary healthcare records were used to prospectively collect all data. Results Two hundred and six patients were collected (66.1±8.7 years; 73.3% male). Eighty-seven out of 206 patients were implanted with an aCRT capable device, but this algorithm was activated at implant and remained enabled at 1-year in 59 patients (aCRT group). The other 147 patients composed the non-aCRT group. At implant left bundle branch block was present in 93% of patients, 69.6% of population was in functional class III or IV and mean left ventricle ejection fraction was of 26.5±5.6%. Non-ischemic cardiomyopathy was present in 63.1% of patients and optimal medical treatment was achieved in majority of population (92% of patients with beta-blockers; angiotensin-converting enzyme inhibitorsor angiotensin II receptor blockersin 89%). The percentage of ventricular pacing through 12 months was 96.1±9.4% in non-aCRT patients and 97.5±2.7% in aCRT patients (p=0.261). In aCRT patients, LV-only pacing accounted for a mean of 53.3±37.6% of all ventricular pacing. After 12-month follow-up period, 25 patients (12.1%) met the primary composite endpoint of death or HF hospitalization. Nine patients died and nineteen patients were admitted due to worsening HF. There was no difference in the risk of all-cause death or HF hospitalization between aCRT and non-aCRT patients (10.2% vs. 12.9% respectively; OR=0.76, CI: 0.29–2.01, p=0.585) Conclusions In this contemporary cohort of HF patients undergoing CRT with high percentages of ventricular pacing, clinical performance of aCRT algorithm was adequate