Comparative Evaluation of Left Ventricular Ejection Fraction Recovery After Primary Percutaneous Coronary Intervention in Anterior Versus Inferior Wall ST-Elevation Myocardial Infarction

Objectives: ST-elevation myocardial infarction (STEMI) remains a leading cause of cardiovascular morbidity and mortality worldwide. Left ventricular ejection fraction (LVEF) is an important prognostic indicator following myocardial infarction and reflects the degree of ventricular recovery after reperfusion therapy. However, evidence regarding differences in LVEF recovery between anterior and inferior wall STEMI following primary PCI remains inconsistent. To compare improvement in LVEF after primary PCI among patients presenting with anterior wall versus inferior wall STEMI. Methodology: This comparative observational study was conducted at the Rawalpindi Institute of Cardiology, Rawalpindi, Pakistan, from June to December 2018. A total of 200 consecutive STEMI patients undergoing primary PCI were enrolled and categorized into Group I (anterior wall MI, n=115) and Group II (inferior wall MI, n=85) according to electrocardiographic criteria. Transthoracic echocardiography was performed before PCI and repeated 24–48 hours after the procedure to assess LVEF using the modified Simpson’s biplane method. Results: The mean age of participants was 54.93±10.43 years, and the majority were male (77.5%). Significant improvement in LVEF was observed in both groups following primary PCI. In Group I, mean LVEF improved from 37.61±9.03% to 48.70±7.68%, representing a mean improvement of 11.09±4.90 percentage points (p<0.001). In Group II, mean LVEF increased from 42.23±7.52% to 52.23±6.22%, with a mean improvement of 10.00±2.98 percentage points (p<0.001). Although anterior wall MI patients demonstrated numerically greater improvement, the inter-group difference in LVEF recovery was not statistically significant (p=0.072). Conclusion: Primary PCI significantly improves left ventricular systolic function in both anterior and inferior wall STEMI. No statistically significant difference was observed in the degree of short-term LVEF recovery between the two infarct locations. These findings support the effectiveness of primary PCI irrespective of infarct site and highlight the need for larger multicenter longitudinal studies to further evaluate long-term ventricular remodeling after STEMI.