Early lumen diameter loss after percutaneous transluminal coronary angioplasty is related to coronary plaque burden: A role for viscous plaque properties in early lumen diameter loss

Objectives: We tested the hypothesis that lumen diameter loss within 1 h af ter percutaneous transluminal coronary angioplasty is related to plaque vol ume parameters. Background: Early lumen diameter loss after coronary balloo n angioplasty may predict restenosis and may paradoxically decrease late lu men diameter loss. Viscous properties of the vessel wall, as would be deter mined by tissue volume and composition, may be involved in early lumen diam eter loss. Methods: Early lumen diameter loss was measured with quantitativ e coronary angiography as the loss in lesion lumen diameter (significant lo ss 0.4 mm) occurring between 5 min and a median of 40 min after successful coronary balloon angioplasty in 68 patients. Thirty-nine patients were eval uated with intravascular ultrasound at the narrowest lumen cross-section of the dilated lesion, 29 patients formed a control group without intravascul ar ultrasound imaging. We tested the relation between intravascular ultraso und parameters and early lumen diameter loss. Results: Early lumen diameter loss of greater than or equal to0.4 mm was present in eight patients (12%) , decreasing lumen diameter from 2.26 +/- 0.36 mm to 1.73 +/- 0.43 mm. Ther e was no difference in the frequency of early lumen diameter loss between t he groups with or without intravascular ultrasound imaging. Univariate intr avascular ultrasound determinants of early lumen diameter loss were media b ounded area (p = 0.01), maximal plaque thickness (p = 0.02), eccentricity i ndex (p = 0.03) and the presence of hard lesions (p = 0.02). Conclusion: Ea rly lumen diameter loss in the first hour after successful coronary balloon angioplasty occurs in a small proportion of patients. It is related to har d lesion type, maximal plaque thickness and eccentricity index, favoring a role for viscous plaque properties in early lumen diameter loss.