Comparison of the clinical characteristics and in hospital outcomes of proximal versus non-proximal lesions in dominant right coronary artery ST-elevation myocardial Infarction

Abstract

Background: Right coronary artery (RCA) ST-elevation myocardial infarction (STEMI) is a critical cardiovascular condition that can lead to significant morbidity and mortality if not treated promptly. Primary percutaneous coronary intervention (PCI) is the gold standard for managing STEMI patients. The objective of this study is to evaluate clinical characteristics and outcome of proximal versus non-proximal, in dominant “right coronary artery (RCA) ST-elevation myocardial infarction (STEMI)” patients undergoing primary PCI at NICVD, Karachi.

Methodology: This retrospective comparative cross-sectional study included equal number of consecutive patients diagnosed with dominant “RCA STEMI” with culprit proximal and non-proximal lesions undergoing primary PCI. In-hospital clinical outcomes including mortality, heart failure, cardiogenic shock, ventricular arrhythmias, myocardial infarction, stent thrombosis, AV block, TPM placement, IABP placement, and other procedure-related complications were compared between the two groups.

Results: Total 355 patients each with proximal lesions and non-proximal lesions were included. Age was similar between the two groups, with no significant difference observed (56.9 ± 10.8 years vs. 56 ± 10.4 years; p = 0.367). Pre-procedure TIMI flow was significantly worse in the proximal lesion group compared to the non-proximal lesion group (TIMI 0: 70.1% vs. 66.8%; p = 0.015). Delay in PCI was noted for 107 (30.2%) vs. 68 (19.2%); p=0.001in proximal compared to the non-proximal group, respectively.

Conclusion: Proximal lesions appear to be associated with poorer initial coronary blood flow and a higher likelihood of in-hospital mortality. Further, a significant delay in intervention was observed for proximal group. Hence, these findings revealed the importance of timely intervention and tailored management strategies based on lesion location in optimizing outcomes for STEMI patients.