Incidence and outcomes of myocardial infarction in patients admitted with acute ischemic stroke

Abstract

Background and Purpose-Data on the incidence and outcomes of acute myocardial infarction (AMI) complicating acute ischemic stroke (AIS) are limited. We aim to evaluate the incidence, treatment patterns, and outcomes of AMI in patients with AIS using a nationwide database. Methods-The National Inpatient Sample was used to identify patient with AIS between 2003 and 2014. Trends of incidence of AMI and its associated in-hospital mortality were evaluated. Univariate and multivariate logistic regressions were used to evaluate predictors of AMI. The impact of AMI on in-hospital outcomes was assessed in a comparative analysis of propensity-matched groups of patients with and without AMI. Results-Patients with AIS (n=864 043) were identified in the national inpatient sample, of whom 13 573 patients (1.6%) had an AMI (79.5% non-ST-segment-elevation myocardial infarction and 20.5% ST-segment-elevation myocardial infarction). In-hospital mortality was 21.4% and 7.1% in propensity-matched cohorts of patients with and without AMI, P<0.001. In-hospital length of stay and cost of care were 50% higher in the AMI group. In a multivariate logistical regression analysis, the strongest predictors of having AMI after AIS were older age, history of coronary artery disease, chronic renal insufficiency, undergoing mechanical thrombectomy, and rhythm and conduction abnormalities. In the AMI group, undergoing coronary angiography and undergoing percutaneous coronary intervention both strongly correlated with lower in-hospital mortality (odds ratio, 0.34 [confidence interval, 0.23-0.51] and 0.26 [confidence interval, 0.20- 0.34], respectively, P<0.001). However, these were only performed in 7.5% and 2% of patients, respectively. Conclusions-AMI complicating stroke carries a substantial in-hospital mortality and cost of care. Patients who underwent coronary angiography with or without intervention may have improved survival although it was only utilized in a minority of patients. Further studies needed to discern the ideal approach in AMI in patients with AIS.