Collateral blood flow can predict myocardial blush grade in primary coronary intervention

Objectives Our aim was to investigate whether collateral flow may predict myocardial blush grade (MBG) in acute myocardial infarction patients undergoing primary percutaneous coronary intervention. Background No-reflow is a well known phenomenon associated with increased morbidity and mortality due to underperfused myocardium; therefore early prediction of no-reflow is of major importance. We have observed that in patients with good collateral filling of the infarct related artery as seen prior to primary angioplasty, the clearance of the contrast medium from the myocardium may be impaired. Methods We retrospectively analyzed the MBG as observed by collateral filling in 81 patients and correlated it with the final MBG. Patients were divided into two groups-those with collateral MBG 0 or 1 (34) and those with myocardial blush 2 or 3 (47). Results Of the 34 patients in the first group 71% remained in the same MBG group after primary percutaneous coronary intervention and the rest improved. Of the 47 individuals with collateral MBG 2 or 3, 87% remained in the same group following primary percutaneous coronary intervention, and the rest deteriorated (P < 0.01 for both groups). Conclusions Collaterals may predict MBG in acute myocardial infarction patients undergoing primary percutaneous coronary intervention.