Incidence and Predictors of 30-Day Unplanned Cardiac Readmission Following Percutaneous Coronary Intervention: Insights from the Victorian Cardiac Outcomes Registry

Background: Unplanned readmission to hospital after percutaneous coronary intervention (PCI) is an important problem, which results in a significant burden to the healthcare system. We sought to determine the incidence and predictors of unplanned cardiac readmission within 30 days of PCI, in a large contemporary Australian cohort. Methods: We prospectively collected data on 17,153 PCI cases between January 2014 and December 2015 in the multi-centre Victorian Cardiac Outcomes Registry (VCOR). We identified patients with an unplanned cardiac readmission within 30 days of PCI, and determined demographic, clinical and procedural characteristics. Results: 644 (3.8%) patients had an unplanned cardiac readmission of which 94.7% had only 1 readmission. The 30-day unplanned readmission rate was higher in patients with acute coronary syndrome (ACS) compared to non-ACS patients (5.1% vs. 2.3%, p < 0.01), but similar in ST-elevation and non-ST-elevation ACS patients (5.0% vs. 5.1%, p = NS). Independent predictors of unplanned readmission included female gender, ACS presentation, severe left-ventricular systolic dysfunction, chronic kidney disease and being on chronic oral anticoagulant therapy (all p < 0.02). Patient age, low socioeconomic status and diabetes status were not associated with increased unplanned readmission (p = NS). There was also no difference in the readmission rate between public and private hospitals (3.8% vs. 3.6%, p = NS). Conclusion: While local unplanned readmission rates following PCI compare favourably with international data, over 300 patients per annum are still being unexpectedly readmitted in the first 30 days following PCI in Victoria. Targeted strategies for high-risk patients are needed to reduce this burden on both patients and the health system.