Acute and mid-term local vascular effects of compliant balloon inflation (GuardWire system) on saphenous vein bypass grafts: an angiographic analysis.
BACKGROUND: The GuardWire distal protection device reduces the incidence of periprocedural complications during percutaneous stenting of diseased saphenous vein grafts. Its mechanism of action is based on the occlusion of the vessel distal to the lesion with an inflated compliant balloon before the intervention, and the aspiration of embolized material after stent implantation. Although no safety issues related to the compliant balloon have been reported in vein graft treatment, concerns related to the potential injury of the balloon on the vessel wall have been raised. We thus evaluated the angiographic outcome of the vein graft segment where the compliant balloon of the GuardWire distal protection device was inflated during percutaneous interventions of diseased vein grafts. METHODS: Forty consecutive patients undergoing vein graft stenting, all with successful delivery of the GuardWire system, were enrolled. All patients underwent 6-months follow-up angiography. Quantitative coronary angiographic analysis of the vein graft segment where the balloon was inflated was performed before and after the procedure, as well as at 6-month follow-up. RESULTS: No differences in reference vessel diameter, minimal luminal diameter and diameter stenosis were evident between the three measurements. In particular, the difference between post-procedural and follow-up minimal luminal diameter (namely late loss) was 0.003+/-0.19 mm (95% confidence interval: -0.06-0.06). CONCLUSIONS: This prospective study supports for the first time the "angiographic safety" of low pressure inflations of a compliant balloon in saphenous vein grafts, suggesting the absence of acute and mid-term effects on the vein graft vessel wall.