Atrial Arrhythmias in Heart Transplant Recipients, Trends and Outcomes for Hospitalizations: Insights from National In-Patient Sample (2005-2014)

Abstract

Background Atrial fibrillation-flutter (AF) has been described in up to a quarter of patients after heart transplant (HT). Data on AF after HT are limited to single center experiences. To bridge this gap, we performed analysis on the National Inpatient Sample (NIS) database to evaluate the trends and in-hospital outcomes of AF post HT from 2005 to 2014. Methods We utilized data from the National Inpatient Sample and the US Census Bureau to calculate annual national rates of in-hospital mortality and length of stay among HT recipients who were admitted with AF for years 2012 to 2015. We compared the in-hospital outcomes between AF post HT and an age and gender propensity score-matched group without AF and performed multivariable logistic regression of significant patient and hospital characteristics to identify predictors of in-hospital mortality. Results A total of 1,000 hospitalizations (mean age 59 years, 719 males, 281 females, 81.3% whites, median CHA2DS2Vasc score 2, interquartile range 1-3) were identified for AF in HT recipients. Most commonly associated comorbidities included diabetes mellitus (34.4%), hypertension (68.3%), Obesity (10.8%) and chronic renal failure (38%). Most hospitalizations were non-elective (79.49%). Anticoagulation (AC) was reported in 11.5% of the hospitalizations. Cardioversion (DCV) was performed in 31.2% and ablation in 11.4% of patients. Hospitalizations for AF undergoing ablation and DCV in HT patients appear to be stable over 10-year study period (P trend=0.4 and 0.6 respectively). Most cardioversions and ablations were reported in men (70%). In-hospital mortality was 1.48%. The mean length of hospitalization was 3.29 days. After propensity match analysis and multivariable logistic regression, AF was not associated with in-hospital mortality (Odds Ratio 1.21, 95% CI 0.8-1.9, P=0.4). Conclusions A small and stable portion of HT recipients is hospitalized for AF from 2005 to 2014. AF was not an independent predictor of mortality.