Comparison of 30-Day Unplanned Readmissions to the Index Versus Nonindex Hospital After Percutaneous Coronary Intervention

There is limited information about readmissions to index compared with nonindex hospitals after percutaneous coronary intervention (PCI). This study aims to evaluate the rates, causes, and outcomes for unplanned readmissions following PCI depending on whether the patients were admitted to the index or nonindex hospital. Patients who underwent PCI between 2010 and 2014 in the United States. Nationwide Readmission Database were evaluated for unplanned readmissions at 30 days to index and nonindex hospitals. A total of 2,183,851 procedures were analyzed, with a 9.2% 30-day unplanned readmission rate documented, and 7.1% and 2.1% of these readmissions were admitted to the index and nonindex hospitals, respectively. There was also a higher prevalence of co-morbidities among patients readmitted to nonindex hospitals, and more patients who were discharged against medical advice at index PCI. Noncardiac readmissions were lower among patients who were readmitted to the index compared with nonindex hospital (53.4% vs 61.1%, p < 0.001). There were greater adjusted odds of acute myocardial infarction (AMI) (odds ratio [OR] 1.14 95%CI 1.06 to 1.22), PCI (OR 2.25 95%CI 2.06 to 2.46), and composite outcome (AMI, readmission PCI, and all-cause death) (OR 1.64 95%CI 1.53 to 1.75) for patients readmitted to the index hospital but their odds of all-cause death were lower (OR 0.77 95%CI 0.68 to 0.88). The majority of readmissions after PCI are to the index hospital that the PCI was undertaken, and these patients are more likely to have a readmission diagnosis of AMI and undergo a repeat PCI but less likely to die compared with patients admitted to a nonindex hospital.