Correlation between Interatrial Septal Thickness and Severity of Coronary Artery Disease in Patients with Myocardial Infarction: An Observational Study

Export Background: Coronary artery disease (CAD) is a significant health burden worldwide, and risk stratification in myocardial infarction (MI) is paramount. Interatrial septal thickness (IAST) measured by echocardiogram may represent a simple, noninvasive marker of CAD. As such, the purpose of this study was to investigate the relationship between IAST and the level of CAD severity in patients with MI. Methodology: In this observational study, patients admitted for acute MI underwent transthoracic echocardiogram and coronary angiography during the same admission. IAST was measured by one experienced observer, and SYNTAX scores were calculated for all patients to account for coronary lesion complexity. Patients were classified by clinical status and by angiographic findings. Statistical analyses included t-tests for the comparisons of means, Spearman’s correlation, and receiver operating characteristics (ROC) curve analysis for the measurement of diagnostic performance. Results: A total of 160 patients were enrolled (123 males, 37 females; mean age 60.2 years). Patients with triple-vessel disease and left main plus triple-vessel disease had higher mean IAST (11.38 mm and 11.68 mm, respectively), whereas single- and double-vessel disease showed lower values (8.47 mm and 8.73 mm, respectively). A statistically significant positive correlation was found between IAST and SYNTAX score (Spearman’s ρ =0.62, P < 0.00001). ROC analysis identified an optimal IAST cutoff value of 10.4 mm for predicting severe CAD (sensitivity – 79.2% and specificity – 69.2%). Conclusion: IAST (cutoff 10.4 mm) demonstrates a significant positive association with CAD severity and may serve as a potential non-invasive marker for early risk stratification in MI patients.