Relationship between Myocardial Blush Grade and LV Function in Acute MI Patients after Primary PTCA

Background- The primary objective of reperfusion therapies for acute myocardial infarction is not only to restore the blood flow in the epicardial coronary artery but also to complete and sustain the reperfusion of the infarcted part of the myocardium. Methods- In this cross-sectional study on 50 patients who underwent primary coronary angioplasty, we assessed the correlation between LV ejection fraction and angiographic evidence of myocardial reperfusion (myocardial blush grade). The myocardial blush grade after the angioplasty procedure was graded by two investigators, who were otherwise blinded to all clinical data. On the 5th day after MI, left ventricular ejection fraction was assessed by 2D echocardiography (Simpson’s method). Results- This study showed that the myocardial blush grade was directly related to the left ventricular function. Ten patients had MBG 0-1, 21 patients had MBG 2, and 19 patients had MBG 3, the mean ejection fraction being 4212.2 %. Severe LV systolic dysfunction was found in six patients, moderate LV systolic dysfunction in 24 patients, and mild LV systolic dysfunction in 14 patients; and the remaining 6 patients had normal LV function. Multivariate analysis showed that there is a direct correlation between MBG and LV function (R=0.77, p<0.01). Conclusion- In patients after reperfusion therapy, the myocardial blush grade as seen on the coronary angiogram is a predictor of left ventricular function and can be used to describe the effectiveness of the myocardial reperfusion (Iranian Heart Journal 2006; 7 (4):13-16).