ABSTRACT
BACKGROUND: Concerns about the efficacy of prophylactic ICD in non-ischemic cardiomyopathy (NICM) heart failure (HF) patients are still present. We aimed to assess whether survival and arrhythmic risk were different among ischemic cardiomyopathy (ICM) and NICM ICD-only patients, along with specific predictors for mortality. METHODS: HF patients undergoing ICD-only implant were extracted from the nationwide multicenter UMBRELLA registry. Arrhythmic events were collected by remote monitoring and reviewed by a committee of experts. RESULTS: 782 patients (556 ICM; 226 NICM) were recruited: mean ejection fraction of 26.6%; 83.4% in NYHA class II-III; mean QRS duration of 108.9â¯ms (only 14.9% with QRSâ¯>â¯130â¯ms). After 4.35â¯years of mean follow-up, all-cause mortality rate was 4.2%/year. In propensity-score (PS) analysis no survival differences between ICM and NICM subgroups appeared (mortality rates: 19.4% vs. 20%, pâ¯=â¯0.375). Age (hazard ratio [HR]â¯=â¯1.02, pâ¯=â¯0.009), diabetes (HRâ¯=â¯2.61, pâ¯≤â¯0.001), chronic obstructive pulmonary disease (HRâ¯=â¯2.13, pâ¯=â¯0.002), and previous HF (HRâ¯=â¯2.28, pâ¯=â¯0.027) correlated with increased mortality for the entire population, however atrial fibrillation (AF) (HRâ¯=â¯2.68, pâ¯=â¯0.002) and chronic kidney disease (HRâ¯=â¯3.74, pâ¯≤â¯0.001) emerged as specific predictors in NICM patients. At follow-up, 134 patients (17.1%) were delivered a first appropriate ICD therapy (5.1%/year) without significant differences between ICM and NICM patients in the PS analysis (17.6% vs. 15.8%, pâ¯=â¯0.968). ICD shocks were associated with a higher mortality (HRâ¯=â¯2.88, pâ¯<â¯0.001) but longer detection windows (HRâ¯=â¯0.57, pâ¯=â¯0.042) correlated with fewer appropriate therapies. CONCLUSIONS: Mortality and arrhythmia free survival is similar among ICM and NICM HF patients undergoing ICD-only implant for primary prevention strategy.
