Outcome of undersized drug-eluting stents for percutaneous coronary intervention of saphenous vein graft lesions

We sought to determine the outcome with undersized drug-eluting stents for percutaneous coronary intervention of saphenous vein graft lesions. Using intravascular ultrasound guidance, 209 saphenous vein graft lesions were treated with drug-eluting stents (153 sirolimus-eluting and 56 paclitaxel-eluting stents). The lesions were divided into 3 groups according to the ratio of the stent diameter to the average intravascular ultrasound reference lumen diameter: group I, <0.89; group II, 0.9 to 1.0; and group III, >1.0. Angiographic no-reflow was defined as a Thrombolysis In Myocardial Infarction flow grade of 0, 1, and 2 after percutaneous coronary intervention. Plaque intrusion was defined as tissue extrusion through the stent struts. Stent malapposition was defined as one or more stent struts that had clearly separated from the vessel wall with evidence of blood speckles behind the strut. No significant differences were found in the use of distal protection devices (group I, 44%; group II, 35%; and group III, 36%; p = 0.5); and no significant differences were found in the incidence of stent malapposition among the 3 groups (group I, 21%; group II, 42%; and group III, 52%; p = 0.001). The plaque intrusion area (group I, 0.13 +/- 0.30 mm(2); group II, 0.25 +/- 0.42 mm(2); and group III, 0.31 +/- 0.40 mm(2); p = 0.018) and plaque intrusion volume (group I, 0.25 +/- 0.68 mm(3); group II, 0.40 +/- 0.68 mm(3); and group III, 0.75 +/- 1.34 mm(3); p = 0.007) were smallest in group I. The plaque intrusion area and plaque intrusion volume correlated with the ratio of the stent diameter to the average intravascular ultrasound reference lumen diameter (r = 0.278, p <0.001 and r = 0.283, p <0.001, respectively). The incidence of a creatine kinase-MB elevation >3 times normal was 6% in group I, 9% in group II, and 19% in group III (p = 0.025). No significant differences were found in the incidence of 1-year target lesion revascularization (group I, 13%; group II, 9%; and group III, 15%; p = 0.5) or target vessel revascularization (group I, 13%; group II, 13%; and group III, 15%; p = 0.9) among the 3 groups. In conclusion, the use of undersized drug-eluting stents to treat patients with saphenous vein graft lesions is associated with a reduction in the frequency of post-percutaneous coronary intervention creatine kinase-MB elevation without an increase in 1-year events.