Type 2 Myocardial Infarction in Young Adults: Insights From the National Readmission Database

Abstract

Introduction Type 2 myocardial infarction (T2MI) is an ischemic myocardial injury in the context of oxygen supply/demand mismatch in the absence of a primary coronary event. T2MI is often diagnosed in patients with a higher risk of morbidity and mortality. T2MI in young adults is poorly understood due to limited available data. Methods The Nationwide Readmission Database 2017-2018 was queried for admission with T2MI diagnosis in young adults (age ≤ 45 years). Index admissions with T2MI were identified. Other types of myocardial infarction and observations with missing data were excluded. December admissions were excluded to allow the 30-day follow-up. Cox proportional hazard multivariate regression model was used to determine predictors of readmissions. All P-values were two-sided, with 0.05 as the threshold for statistical significance. Results A total of 11,750 patients with a secondary diagnosis of T2MI were admitted between October 2017 and November 2018. The main primary etiologies of index admission were sepsis (14%) followed by hypertensive heart disease with heart failure (11%) and hypertensive emergency (7%), while main etiologies of readmission were hypertensive heart disease with heart failure (12%) followed by sepsis (9%) and acute kidney injury (3%). Valvular heart disease, chronic pulmonary disease, drug abuse, and depression were amongst the predictors of all-cause readmission. Conclusion We identified primary etiologies of admission and readmission, and predictors of readmissions in young adults presenting with T2MI. Further studies are needed to guide the management of T2MI in this age group.