Frequency of 30-day readmission and its causes after percutaneous coronary intervention in acute myocardial infarction complicated by cardiogenic shock.

BACKGROUND: Survival after percutaneous coronary intervention (PCI) in acute myocardial infarction complicated by cardiogenic shock (AMI-CS) has increased over the years. Short-term readmission rates in this high-risk population remain unknown.

METHODS: We queried the United States (U.S.) Nationwide Readmission Database (NRD) from January 2010 to November 2014 using the International Classification of Diseases-Ninth edition, Clinical Modification (ICD-9 CM) codes to identify all patients ≥18 years readmitted within 30 days after surviving an index hospitalization for PCI in AMI-CS. Incidence, etiologies, and predictors of 30-day readmission were analyzed.

RESULTS: Among 46,435 patients who survived to discharge after PCI in AMI-CS, 9,020 (19.4%) were readmitted within 30 days. Median time to 30-day readmission was 11 days. Cardiac conditions were the most common causes of readmission (57.8%). Heart failure was the leading readmission diagnosis (24.8%). Private insurance including HMO and self-pay were predictive of lower 30-day readmission. Among other covariates, female sex, comorbidities such as heart failure, atrial fibrillation, in-hospital complications such as major bleeding, sepsis, respiratory complications, AKI requiring dialysis, utilization of mechanical circulatory support (IABP and ECMO) were independently predictive of 30-day readmission. Trend analysis showed decline in 30-day readmission rates from 21.9% in 2010 to 17.9% in 2014 (ptrend  < 0.001).

CONCLUSION: In this large real-world database, one in five patients receiving PCI in AMI-CS was readmitted within 30 days after discharge. Cardiac conditions were the most common causes of readmission. Insurance type had significant influence on 30-day readmission.