Etiologies and predictors of 30-day readmissions in patients undergoing percutaneous mechanical circulatory support–assisted percutaneous coronary intervention in the United States: Insights from the Nationwide Readmissions Database

Background: Patients undergoing percutaneous mechanical circulatory support (pMCS)-assisted percutaneous coronary intervention (PCI) represent a high-risk group vulnerable to complications and readmissions. Hypothesis: Thirty-day readmissions after pMCS-assisted PCI are common among patients with comorbidities and account for a significant amount of healthcare spending. Methods: Patients undergoing PCI and pMCS (Impella, TandemHeart, or intra-aortic balloon pump) for any indication between January 1, 2012, and November 30, 2014, were selected from the Nationwide Readmissions Database. Patients were identified using appropriate ICD-9-CM codes. Clinical risk factors and complications were analyzed for association with 30-day readmission. Results: Our analysis included 29 247 patients, of which 4535 (15.5%) were readmitted within 30 days. On multivariate analysis, age ≥ 65 years, female sex, hypertension, diabetes, chronic lung disease, heart failure, prior implantable cardioverter-defibrillator, liver disease, end-stage renal disease, and length of stay ≥5 days during index hospitalization were independent predictors of 30-day readmission. Cardiac etiologies accounted for ~60% of readmissions, of which systolic or diastolic heart failure (22%), stable coronary artery disease (11.1%), acute coronary syndromes (8.9%), and nonspecific chest pain (4.0%) were the most common causes. In noncardiac causes, sepsis/septic shock (4.6%), hypotension/syncope (3.2%), gastrointestinal bleed (3.1%), and acute kidney injury (2.6%) were among the most common causes of 30-day readmissions. Mean length of stay and cost of readmissions was 4 days and $16 191, respectively. Conclusions: Thirty-day readmissions after pMCS-assisted PCI are common and are predominantly associated with increased burden of comorbidities. Reducing readmissions for common cardiac etiologies could save substantial healthcare costs.