Abstract 4726: Clinical Outcome After Percutaneous Coronary Intervention Using Undersized Drug-Eluting Stents for Saphenous Vein Graft Lesions
Background: We sought to determine the efficacy of undersized drug-eluting stent (DES) implantation on clinical results after percutaneous coronary intervention (PCI) for saphenous vein graft (SVG) lesions.
Methods: Using intravascular ultrasound (IVUS) guidance, 209 SVG lesions were treated by DES (153 sirolimus-eluting and 56 paclitaxel-eluting stents). Lesions were divided into three groups according to the ratio of stent diameter to average IVUS reference lumen diameter: Group I <0.89, Group II 0.9–1.0, and Group III >1.0. Angiographic no-reflow was defined as post-PCI TIMI flow grade 0, 1, and 2. Plaque prolapse (PP) was defined as tissue extrusion through the stent struts. Stent malapposition was defined as one or more stent struts clearly separated from the vessel wall with evidence of blood speckles behind the strut.
Results: There was no significant difference in the incidence of stent malapposition among the 3 groups. However, PP was observed least frequently (Group I: 21%, Group II: 42%, and Group III: 52%, P=0.001) and PP area (Group I: 0.13±0.30 mm2, Group II: 0.25±0.42 mm2, and Group III: 0.31±0.40 mm2, P=0.018) and PP volume (Group I: 0.25±0.68 mm3, Group II: 0.40±0.68 mm3, and Group III: 0.75±1.34 mm3, P=0.007) were smallest in Group I; and PP area and volume correlated with the ratio of stent diameter to average IVUS reference lumen diameter (r=0.278, P<0.001, and r=0.283, P<0.001, respectively). The lowest frequency of creatine kinase (CK)-MB elevation >3 times normal was seen in Group I (Group I: 6%, Group II: 9%, and Group III: 19%, P=0.025); and this degree of CK-MB elevation was observed more frequently in lesions with PP compared to lesions without PP (19% vs. 6%, P=0.005). There were no significant differences in one-year target lesion revascularization (Group I: 13%, Group II: 9%, and Group III: 15%, P=0.5) and target vessel revascularization (Group I: 13%, Group II: 13%, and Group III: 15%, P=0.9) among the 3 groups.
Conclusions: The use of undersized DES to treat patients with SVG lesions is associated with a reduction in frequency of post-PCI CK-MB elevation, presumably because of lesser degrees of PP, with no increase in one year events.