Acute myocardial infarction and acute heart failure among renal transplant recipients: a national readmissions database study

Background: The literature on the mortality and 30-day readmissions for acute heart failure and for acute myocardial infarction among renal-transplant recipients is limited. Objective: To study the in-hospital mortality, cardiovascular complications, and 30-day readmissions among renal transplant recipients (RTRs). Methods: Data from the national readmissions database sample, which constitutes 49.1% of all hospitals in the United States and represents more than 95% of the stratified national population, was analyzed for the years 2012–2018 using billing codes. Results: A total of 588,668 hospitalizations in renal transplant recipients (mean age 57.7 ± 14.2 years; 44.5% female) were recorded in the study years. A total of 15,788 (2.7%) patients had a diagnosis of acute heart failure; 11,320 (71.7%) had acute heart failure with preserved ejection fraction and 4468 (28.3%) had acute heart failure with reduced ejection fraction; 17,256 (3%) patients had myocardial infarction, 3496 (20%) had ST-Elevation myocardial infarction while 13,969 (80%) had non-ST-elevation myocardial infarction. Overall, 11,675 (2%) renal-transplant patients died, of whom 757 (6.5%) had acute heart failure, 330 (2.8%) had acute reduced and 427 (3.7%) had acute preserved ejection fraction failure. Among 1652 (14.1%) patient deaths with myocardial infarction, 465 (4%) were ST-elevation- and 1187 (10.1%) were non-ST-Elevation-related. The absolute yearly mortality rate due to acute heart failure increased over the years 2012–2018 (p-trend 0.0002, 0.001, 0.002, 0.05, respectively), while the mortality rate due to myocardial infarction with ST-elevation decreased (p-trend 0.002). Conclusion: Cardiovascular complications are significantly associated with hospitalizations among RTRs. The absolute yearly mortality, and rate of heart failure (with reduced or preserved ejection fraction) increased over the study years, suggesting that more research is needed to improve the management of these patients. Graphical abstract: [Figure not available: see fulltext.]