Some studies suggest better outcomes after the use of thrombolytics in inferior ST-elevation myocardial infarction (STEMI) compared to other locations. The goal of this study is to compare the clinical endpoints of thrombolytic-treated STEMI based on coronary artery distribution.

The study population was extracted from the 2014 Nationwide Readmissions Data using the International Classification of Diseases, Ninth Revision, Clinical Modifications codes for STEMI, thrombolytic infusion, and complications of STEMI. Primary study endpoints included in-hospital all-cause mortality, length of hospital stay (LOS), cardiogenic shock, and mechanical complications of STEMI.

A principal diagnosis of thrombolytic-treated STEMI was identified for in 1231 patients (mean age 61.5 years; 26.5% female). Four hundred and thirty-one STEMIs occurred in the left anterior descending (LAD) artery distribution, 124 in the left circumflex (LCX) artery distribution, and 676 in the right coronary artery (RCA) distribution. In comparison to the LAD and LCX distributions, thrombolytic-treated STEMIs in the RCA distribution were associated with lower mortality (6.5% with LAD, 5.7% with LCX, and 3.6% with RCA; p = 0.02), fewer cardiogenic shock (12.3% with LAD, 12.1% with LCX, and 7.7% with RCA; p = 0.01), and shorter LOS (4.5 days with LAD, 3.9 with LCX, and 3.6 days with RCA; p < 0.01). Mechanical complications showed no significant difference based on coronary distribution (2.3% with LAD, 3.2% with LCX, and 1.2% with RCA; p = 0.17).

Thrombolytic-treated STEMIs in the RCA distribution were associated with lower in-hospital all-cause mortality, cardiogenic shock, and shorter LOS. Mechanical complications were not different based on coronary distribution.