Timing and Causes of Unplanned Readmissions After Percutaneous Coronary Intervention

Objectives The aim of this study was to describe the rates and causes of unplanned readmissions at different time periods following percutaneous coronary intervention (PCI). Background The rates and causes of readmission at different time periods after PCI remain incompletely elucidated. Methods Patients undergoing PCI between 2010 and 2014 in the U.S. Nationwide Readmission Database were evaluated for the rates, causes, predictors, and costs of unplanned readmission between 0 and 7 days, 8 and 30 days, 31 and 90 days, and 91 and 180 days after index discharge. Results This analysis included 2,412,000 patients; 2.5% were readmitted between 0 and 7 days, 7.6% between 8 and 30 days, 8.9% between 31 and 90 days, and 8.0% between 91 and 180 days (cumulative rates 2.5%, 9.9%, 18.0%, and 24.8%, respectively). The majority of readmissions during each time period were due to noncardiac causes (53.1% to 59.6%). Nonspecific chest pain was the most common identifiable noncardiac cause for readmission during each time period (14.2% to 22.7% of noncardiac readmissions). Coronary artery disease including angina was the most common cardiac cause for readmission during each time period (37.4% to 39.3% of cardiac readmissions). The second most common cardiac cause for readmission was acute myocardial infarction between 0 and 7 days (27.6% of cardiac readmissions) and heart failure during all subsequent time periods (22.2% to 23.7% of cardiac readmissions). Conclusions Approximately 25% of patients following PCI have unplanned readmissions within 6 months. Causes of readmission depend on the timing at which they are assessed, with noncardiovascular causes becoming more important at longer time points.