Intravascular ultrasound for evaluation of initial vessel patency and early outcome following directional coronary atherectomy

Elastic recoil and thrombus formation may potentially occur following direc tional coronary atherectomy (DCA) confounding the assessment of late vascul ar remodeling. Since intravascular ultrasound (IVUS) data on early outcome of DCA is not available, we used IVUS to investigate whether elastic recoil or thrombus formation can affect early (4 hr) outcome. Quantitative corona ry angiography (QCA) and IVUS were performed in high-grade coronary lesions in 32 consecutive patients before, immediately after, and 4 hr after DCA, Late clinical follow-up was obtained after a maximum interval of 2 years. S ignificant acute elastic recoil was observed by both IVUS (19% +/- 14%) and QCA (19% +/- 12%), but there was no further recoil after 4 hr. DCA reduced plaque area by 51% +/- 13%, an effect that was stable after 4 hr, indicati ng the absence of relevant thrombus formation, Residual area stenosis by IV US was not related to the occurrence of late clinical events (n = 8), Mecha nical recoil or thrombus formation do not hamper initial lumen gain achieve d by DCA, Although QCA significantly underestimated residual plaque burden after DCA when compared to IVUS, the degree of residual area stenosis did n ot identify patients suffering from cardiac events on follow-up. Cathet. Ca rdiovasc. Intervent. 47:14-22, 1999, (C) 1999 Wiley-Liss, Inc.