Background: Data on morbidity and mortality on acute myocardial infarction (AMI) based on coronary region is obtained from studies conducted over three decades ago. The aim of this study is to evaluate morbidity and mortality outcomes, in respect to coronary anatomy region in one of the largest public national databases available.
Methods: This is a retrospective analysis based on the 2014 Nationwide Inpatient Sample, the largest publicly available inpatient database in the U.S. Patients older than 18 years and with primary diagnosis of AMI were included in the analysis. Primary outcome was mortality. Secondary outcomes include ICU admission, and cardiogenic shock. Multivariate regression analyses were performed to test for independent associations between outcomes and variables of interest. Diagnoses and procedures were identified using ICD-9-CM codes. Analysis was performed using Stata 14.2.
Results: We identified a total of 612,575 patients with a primary diagnosis of AMI. Among these patients 2.2% had anterolateral wall (AL) infarction, 10.5% inferior wall (IW), 7.3% anterior wall (AW), 1.9% inferior lateral (IL), 1.9% inferior posterior (IP), 1.3% lateral wall (LW), 0.3% posterior wall (PW), and 70.4% subendocardial infarction. PW infarction followed by AL infarction had the greatest risk for in-hospital mortality, risk of ICU admission, and cardiogenic shock. Patients with subendocardial infarctions were less likely to be associated with in-hospital mortality, ICU admission, or cardiogenic shock compared to the rest of the cohort population.
Conclusion: There are significant differences in morbidity and mortality in patients with AMI based on the region of infarction. Even though PW accounted for smallest percentage of AMI in our cohort, it was associated with the greatest morbidity and mortality. Further prospective studies should be conducted.