Angiographic predictors of plaque progression are weak and few: length, irregular surface, turbulence, low shear, and (in some studies) eccentricity and calcification. Having noted plaques that briefly retained dye after angiography, we interpreted these as plaques with a fissured surface or neovascularization and hypothesized that progression would be predicted by “plaque blush.”

Plaques (<50% diameter stenosis) in 68 pairs of angiograms, 5.6 ± 4.8 months apart, were reviewed by 2 blinded observers. The presence of plaque blush, calcification, clot (mobile defect), eccentricity, and a branch point location were compared between progressing (≥20% stenosis increase) and nonprogressing plaques.

Sixteen lesions in 15 patients progressed from 29% ± 13% to 68% ± 14% over a period of 8.1 ± 7.9 months. Patients with and without progression were similar in sex, age, congestive heart disease risk factors, medications, interval between angiograms, clinical presentation, and initial stenosis severity. By logistic regression, plaque blush (BL) (P = .002), calcification (CA) (P = .024), and a branch (BR) point location (P = .001) predicted plaque progression. The odds ratio for plaque progression (ORp) was calculated as ORp = e^{2.5 × BL + 1.8 × CA + 2.6 × BR}. Using an ORp of 1/3, the model has 81% sensitivity and 77% specificity. A second analysis in which each progressive lesion was compared with proximal and distal lesions and with one in a different coronary artery yielded similar results.

In mild to moderate coronary stenoses, studied retrospectively, plaque blush (a new sign) and a branch point location were strong predictors of plaque progression, whereas calcification was a weak predictor of progression.