Prediction of Restenosis After Coronary Balloon Angioplasty

Background Intracoronary ultrasound (ICUS) imaging is potentially suitable to identify lesions at high risk of restenosis after percutaneous transluminal coronary angioplasty (PTCA), but it has not been studied systematically. Methods and Results We recruited 200 patients in whom ICUS studies were performed after successful PTCA and related their ICUS parameters to 6-month follow-up quantitative coronary angiography. This was performed in 164 patients (82%), yielding 170 lesions for analysis. The overall incidence of a 50% diameter stenosis at follow-up (categorical restenosis) was 29.4%. Quantitative ICUS parameters were weakly but significantly related to follow-up minimal luminal diameter on quantitative coronary angiography (lumen area: R2=.36, P=.0001; vessel area: R2=.29, P=.0002; plaque area: R2=-.18, P=.021; percent obstruction: R2=-.15, P=.05), but categorical restenosis was not significantly related to these parameters (P=.63, .77, .38, and .08, respectively). There were no significant predictors of restenosis in ICUS parameters of plaque morphology: eccentric versus concentric (P=1.0), plaque type (hard, soft, or calcific, P=.98), or the number of calcified quadrants (P=.41). There were no significant predictors of restenosis in two predefined types of vessel-wall disruptions: (1) rupture: presence (P=.79), depth (partial versus complete, P=.85), or extent in quadrants (P=.6), and (2) dissection: presence (P=.31), depth (P=.82), or extent (P=.38). Conclusions Qualitative ICUS parameters after PTCA did not predict restenosis. A larger lumen and vessel area and a smaller plaque area by ICUS were associated with a larger angiographic minimal lumen diameter at follow-up, but these parameters were not significantly related to categorical restenosis.