Comparative analysis of coronary angiographic morphology following restenosis

The site and angiographic morphology of restenotic lesions following initially successful coronary angioplasty (PTCA) were compared to the original pre-PTCA stenosis and the immediate post-PTCA result. Forty-seven patients with 55 restenoses were analyzed. All patients with repeat angiography for recurrent ischemia 1 to 12 months post-PTCA documenting restenosis were included. Two orthogonal angiographic views best showing the initial lesion, immediate post-PTCA result, and the restenosis lesion, were selected and matched for angulation and cardiac cycle phase. Individual frames were traced and magnified. Restenosis lesions were similar in morphology to the pre-PTCA lesions in 29 of 55 (53%) and to the post-PTCA lesions in only 25 of 55 (46%) ( p =NS). However, when the lesions with residual post-PTCA stenosis of >25% luminal diameter narrowing were excluded from the analysis, the post-PTCA lesion morphology was similar to restenosis morphology in 25 of 30 (83%), whereas pre-PTCA and restenosis morphology was similar in only 15 of 30 (50%) lesions ( p p =0.01) in predicting restenosis morphology, 15 of 17 (88%), than was pre-PTCA morphology, 8 of 17 (47%). When the restenosis occurred >5 mm distant from the original site (group 2), there was no significant difference in the association between pre-PTCA versus post-PTCA morphology and restenosis morphology. Thus restenosis morphology is usually dissimilar to the pre-PTCA stenosis morphology. These data suggest that the reparative processes post-PTCA are of critical importance in determining the occurrence of restenosis, and argue against the hypothesis that inadequate dilatation and/or inadequate remodeling are frequent causative factors when the residual narrowing is 25%.