Survival among ischemic and non-ischemic heart failure patients with primary implantable cardioverter defibrillator therapy in Korea: a nationwide cohort study

Abstract

Abstract Background Concerns still exist about the efficacy of prophylactic implantable electrocardiogram defibrillators (ICD) in patients with non-ischemic heart failure (HF). We evaluated the mortality and predictors of mortality in patients with prophylactic ICD implantation for ischemic and non-ischemic HF. Methods From 2008 to 2017, 1097 patients (667 non-ischemic; 430 ischemic) with prophylactic ICD implantation who were aged 19 years or older were identified from the Korean National Health Insurance Service database. We used propensity score overlap weighting to correct for differences between two groups. Results Compared with non-ischemic HF patients, ischemic HF patients were older (67.0±10.1 years vs. 61.8±14.2), more often male (71.4% vs. 63.7%), and had more comorbidities. During a median follow-up of 37.3 months (interquartile range (IQR), 14.2–53.8 months), all-cause death was higher in unweighted ischemic than non-ischemic HF patients (10.9 and 6.4 per 100 person-years, hazard ratio [HR] 1.74, 95% confidence interval [CI] 1.38–2.20, p<0.001). However, after weighting, annual all-cause mortality rate was similar in both groups (9.5 vs. 8.8 per 100 person-years) without difference in the risk of all-cause death (HR 1.08, 95% CI 0.68–1.71, p=0.755). Older age and chronic kidney disease were independent predictors of all-cause mortality in both groups. There was also no difference in cardiac and non-cardiac mortality between weighted non-ischemic and ischemic HF groups. Conclusions All-cause, cardiac and non-cardiac mortality were similar between non-ischemic and ischemic HF patients undergoing prophylactic ICD implantation. Our findings support the current guidelines recommendation for primary-prevention ICD in HFrEF patients with ischemic and non-ischemic HF. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Korean Healthcare Technology R&D project funded by the Ministry of Health and Welfare