LATE REGRESSION OF THE DILATED SITE AFTER CORONARY ANGIOPLASTY - A 5-YEAR QUANTITATIVE ANGIOGRAPHIC STUDY

Background Limited data are available on the changes that occur at the dilated site late after coronary angioplasty. The aim of this study w as to evaluate with quantitative angiography the natural history of ch anges that occur in the dilated segment between ''early'' (approximate to 6 months) and ''late'' (approximate to 5 years) follow-up after an gioplasty. Methods and Results Of 127 consecutive patients (174 lesion s) with successful angioplasty, 125 underwent early angiography. Three patients subsequently died, and 24 underwent revascularization surger y or repeated angioplasty, giving a study-eligible population of 98 pa tients. Quantitative angiographic analysis was performed before and im mediately after angioplasty and at early and late follow-up in the stu dy population of 84 patients (115 lesions), which was 86% of study-eli gible patients. Mean lesion diameter stenosis decreased from 36.3+/-14 .2% at early to 29.6+/-13.5% at late follow-up (P<.0001). No lesion de veloped late restenosis by the 50% diameter loss criterion. Late regre ssion was related to stenosis severity at early angiography (r=-.58, P <.001). Subgroups at early angiography of 40% to 49% stenosis and grea ter than or equal to 50% stenosis showed significant regression at lat e angiography. Conclusions Lesion regression at the dilated site is co mmon late after angioplasty. The more severe a stenosis is at early an giography, the more likely the chance that there will be late regressi on. A strategy of watchful waiting may be appropriate for patients wit h restenotic lesions of borderline severity.