Impact of Atrial Fibrillation on Hospitalization Outcomes of Heart Failure in Patients ≥ 60 Years with Implantable Cardioverter Defibrillator

Abstract

The impact of atrial fibrillation (AF) on the hospitalization outcomes in patients ≥ 60 years of age with implantable cardioverter defibrillators (ICD) is not well studied. We queried the National Inpatient Sample database for all patients aged ≥ 60 who had a history of ICD placement, and were admitted with a primary diagnosis of heart failure (HF) during the years 2016-2017. Patients were stratified into 2 groups based on their history of AF. The primary outcome of the study was all-cause in-hospital mortality. Secondary outcomes included cardiogenic shock, myocardial infarction (MI), ventricular fibrillation (VF), stroke and acute kidney injury (AKI). The association between different age strata and outcomes was investigated. The hospitalization outcomes were modeled using logistic regression. A total of 178,045 patients were included, of whom 56.2% had AF. AF correlated with increased mortality (A-OR 1.22 (95% CI: 1.06-1.4), p=0.005), cardiogenic shock (A-OR 1.21 (95%CI: 1.08-1.36), p<0.001), AKI (A-OR 1.12 (95%CI: 1.06-1.17), p<0.001 and lower risk for MI (A-OR 0.79 (95% CI: 0.68-0.9), p<0.001. There was no correlation between AF and risk for VF or stroke. A significant correlation between AF and higher risk for mortality, cardiogenic shock and AKI was demonstrated in ages ≤ 75, ≤ 75, and ≤ 80 years, respectively. In contrast, a significant correlation between AF and lower risk for MI is only demonstrated at age > 70 years. We conclude that AF is an independent predictor for increased all-cause in-hospital mortality and cardiogenic shock. Such risk is influenced by age.