Characteristics and Outcomes of Patients Admitted With Type 2 Myocardial Infarction

Type 2 myocardial infarction (Type 2 MI) is a common problem and carries a high diagnostic uncertainty. Large studies exploring outcomes in type 2 MI are lacking. Nationwide Readmission Database (2017) was queried using the International Classification of Diseases codes (ICD-10-CM) to identify type 2 MI patients. Characteristics, in-hospital outcomes, 30-day readmissions, and predictors of in-hospital mortality as well as 30-day readmissions were explored. We identified 21,738 patients with a diagnosis of type 2 MI. Most common primary diagnosis at presentation included infection/sepsis (27.5%), hypertensive heart disease (15.3%) and pulmonary diseases (8.5%). Overall, in-hospital mortality and 30-day readmission for patients with type 2 MI were 9.0% and 19.1% respectively. On multivariable analysis, significant predictors of increased in-hospital mortality included male gender, coexisting atrial fibrillation/flutter, peripheral vascular disease, coagulopathy, malignancy, and fluid/electrolyte abnormalities. Significant predictors of 30-day readmission were coexisting diabetes mellitus, atrial fibrillation/ flutter, carotid artery stenosis, anemia, COPD, CKD and prior history of myocardial infarction, A primary diagnosis of sepsis, pulmonary issues including respiratory failure, neurological conditions including stroke carried highest risk of mortality however readmission risk was not influenced by primary diagnosis at presentation. In conclusion, approximately 1 in 10 patients admitted for type 2 MI died during admission, and nearly 1 in 5 patients were readmitted at 30 days after discharge. In-hospital mortality varied based on associated primary diagnosis at presentation. Proposed predictive model for mortality and 30-day readmission in our study can help to target high risk patients for post-Type 2 MI care.