Clinical outcomes of acute myocardial infarction with occluded left circumflex artery

Area of Science:

• Cardiology
• Internal Medicine
• Diagnostic Imaging

Background:

• Left circumflex artery (LCX) related acute myocardial infarction (AMI) is frequently underdiagnosed using standard 12-lead electrocardiograms (ECG).
• Limited research exists on the specific clinical characteristics of LCX-related AMI.

Purpose of the Study:

• To investigate the clinical features and in-hospital mortality of patients with angiographically confirmed LCX-related AMI.
• To compare these characteristics with AMI caused by occlusion in the left anterior descending (LAD) and right coronary arteries (RCA).

Main Methods:

• Analysis of 2281 AMI patients from the Korea Acute Myocardial Infarction Registry (KAMIR) with single occluded culprit vessels.
• Patients were categorized into three groups based on the culprit artery: LAD, RCA, and LCX.
• Comparison of clinical presentation, treatment, and outcomes among the groups.

Main Results:

• LCX-related AMI patients were less likely to exhibit ST-elevation on ECG (46.3% vs. 87.0% LAD, 82.3% RCA).
• Fewer LCX patients received primary percutaneous coronary intervention (PCI) (43.4% vs. 78.9% LAD, 74.5% RCA) and had door-to-balloon times <90 minutes (31.3% vs. 52.8% LAD, 51.0% RCA).
• No significant difference in hospital mortality was observed between the groups, though multivariate analysis indicated primary PCI reduced mortality.

Conclusions:

• AMI patients with LCX occlusion present with less ST-elevation and undergo primary PCI less frequently.
• Physicians must maintain a high index of suspicion for LCX occlusion in patients with chest pain and non-diagnostic ECGs.
• Early consideration of LCX involvement is critical for timely diagnosis and management of AMI.