Value of the American College of Cardiology/American Heart Association angiographic classification of coronary lesion morphology in patients with in-stent restenosis: Insights from the Restenosis Intra-stent Balloon angioplasty versus elective Stenting (R

Background The implications of the American College of Cardiology/American Heart Association (ACC/AHA) lesion classification in patients with in-stent restenosis (ISR) are unknown. Methods Four hundred fifty patients included in the RIBS randomized study were analyzed. A centralized core laboratory assessed ISR classifications including ACC/AHA, the classification of Mehran et al (Circulation 1999;100:1872-8), diffuse/focal, and a new quantitative ISR index (lesion length/stent length). Logistic regression models were constructed for prespecified outcome measures including (1) unsatisfactory acute results and (2) recurrent restenosis rate. Results Complex (B2/C) lesions (78%) more frequently obtained unsatisfactory acute results (20% vs 8%, P = .007), smaller minimal lumen diameter after the procedure (2.45 ± 0.5 vs 2.73 ± 0.5 mm, P = .001) and at follow-up (1.48 ± 0.8 vs 1.94 ± 0.8 mm, P = .0001), and had a higher restenosis rate (43 vs 24%, P = .001) than simple (A/B1) lesions. On logistic regression analysis, all classification schemes were useful to predict unsatisfactory initial results (area under the curve: 0.63, 0.61, 0.59, and 0.62) and recurrent restenosis (area under the curve: 0.60, 0.64, 0.61, and 0.63). The predictive ability of these schemes persisted despite adjustment for potential confounders. Although the ACC/AHA classification was a better predictor of acute results, the classification of Mehran was superior to predict restenosis. Conclusions The ACC/AHA classification provides a useful tool to determine acute procedural results and the long-term angiographic outcome of patients with ISR.