Evaluation of collateral circulation with clinical, electrocardiographic, and angiographic parameters in patients with acute myocardial infarction

OBJECTIVES
We investigated the presence of collateral circulation (CC) during early period of acute myocardial infarction (AMI) and evaluated its relationship with clinical, electrocardiographic, and angiographic parameters.

STUDY DESIGN
İn 79 patients (63 men, 16 vvomen; mean age 57 years) who presented within the first six hours of AMİ, coro-nary angiography was performed before primary angioplasty to determine the infarct-related artery (IRA), the number of arteries with significant stenosis (≥50%), localization of stenosis (proxi-mal, middle, or distal), and the presence of CC. The presence of Q waves and reciprocal ST-segment changes were evaluated on initial electrocardiograms. Collateral circulation to the IRA was graded according to the Rentrop scoring system.

RESULTS
Collateral circulation to the IRA was detected in 31 patients (39.2%). İnfarct-related artery was the left anterior descending (LAD) coronary artery in 43 patients (54.4%), circumflex (Cx) artery in 11 patients (13.9%), and the right coronary artery (RCA) in 25 patients (31.7%). On initial electrocardiograms, Q wave was absent in 34 patients (43%) and reciprocal ST-segment depression was present in 53 patients (67.1%). Collateral circulation was more common in RCA occlusions than those involving the LAD and Cx arteries (60%, 32.6%, and 18.2%, respectively; p=0.012). The presence of CC was significantly correlated with hypertension (r=0.226, p=0.045) and RCA occlusion (r=0.309, p=0.006). In multiple regression analysis, only RCA occlusion was found to be an independent predictor for CC (r=0.377, p<0.001).

CONCLUSION
In the early period of AMİ, collateral circulation becomes functional in a considerable number of patients who have hypertension and RCA occlusion. This may be helpful in choosing between conservative and invasive treatments.