Association of coronary artery dominance and mortality rate and complications in patients with ST segment elevation myocardial infarction treated with primary percutaneous coronary intervention

Percutaneous coronary intervention (PCI) is the treatment of choice for patients with ST‑segment elevation myocardial infarction (STEMI). Effect of coronary artery dominance on the patients’ outcome following primary PCI (PPCI) is not fully investigated. We investigated the association of coronary artery dominance with complications and 1‑year mortality rate of PPCI.

In this retrospective study, patients with STEMI treated with PPCI from March 2016 to February 2018 were divided into three groups based on their coronary dominancy: left dominance (LD), right dominance (RD), and codominant. Demographic characteristics, medical history, results of physical examination, electrocardiography, angiography, and echocardiography were compared between the groups.

Of 491 patients included in this study, 34 patients (7%) were LD and 22 patients (4.5%) were codominant. Accordingly, 54 propensity‑matched RD patients were included in the analysis. The demographics and comorbidities of the three groups were not different (P > 0.05); however, all patients in the RD group had thrombolysis in myocardial infarction (TIMI) 3, while five patients in the LD and five patients in the codominant group had a TIMI ≤2 (P = 0.006). At admission, the median left ventricular ejection fraction (LVEF) was highest in RD patients and lowest in LD and codominant patients (34%, P = 0.009). There was no difference in terms of success or complications of PCI, in‑hospital, and 1‑year mortality rate (P > 0.05).

Patients with left coronary artery dominance had a higher value of indicators of worse outcomes, such as lower LVEF and TIMI ≤ 2, compared with RD patients, but not different rates of success or complications of PCI, in‑hospital, and 1‑year mortality. This finding may suggest that interventionists should prepare themselves with protective measures for no‑reflow and slow‑flow phenomenon and also mechanical circulatory support before performing PPCI in LD patients.