The Effects of Coronary Artery Remodeling on the Developments of Collateral Blood Flow in Patients with Acute Myocardial Infarction Treated with Primary Angioplasty

Background: The relation between pressure-derived fractional collateral flow (PDCF) and coronary arterial remodeling remains uncertain in acute myocardial infarction. Methods: We evaluated the effect of arterial remodeling on the development of PDCF in 72 patients with first acute myocardial infarction (pain onset <12 h) treated with primary angioplasty. Intravascular ultrasound study was performed before intervention. The remodeling index (RI) was defined as a ratio of (lesion/proximal reference) external elastic membrane area. Positive remodeling was defined as a RI >1.0 and nonpositive remodeling as a RI ≤1.0. Using a 0.014-in. fiber optic pressure monitoring guide wire, the PDCF index was measured by simultaneous measurement of mean aorta pressure (Pao), distal coronary pressure during the balloon occlusion (Pocc), and central venous pressure (CVP): PDCF index= 100×(Pocc-CVP)/(Pao-CVP). Sufficient collateral was defined as PDCF index >24% and insufficient collateral as PDCF index ≤24%. Results: The RI was 1.04±0.15 in the lesions with sufficient collateral and 1.03±0.16 in the lesions with insufficient collateral (p=0.812). There was no significant difference in the frequency of positive remodeling between the 2 groups (55% vs. 54%, respectively, p=0.966). The PDCF index was 20±11% and 20± 9% in positive and nonpositive remodeling, respectively (p=0.891). There was no significant correlation between RI and PDCF index (r=0.027, p=0.823). Conclusions: The pattern of coronary arterial remodeling might not influence the development of collateral blood flow in patients with acute myocardial infarction treated with primary angioplasty. (Korean Circulation J 2004;34 (1):47-52)