Abstract
Objective: Shunt obstruction is usually treated by removing the thrombus using a Fogarty balloon catheter. However, once patency has been restored, treatment of the cause of obstruction is often disregarded. We devised a one-stage endovascular treatment for obstruction, including removal of the thrombus, treatment of the lesion responsible for obstruction, and postoperative dialysis, that can be performed without hospitalization. From January 2007 to September 2009, we treated graft (treated artificial shunt graft) obstruction by PTA using a percutaneous thrombectomy catheter (hydrolyzer) (hydro-PTA) in 59 patients. The therapeutic results were evaluated, and the period until restenosis was compared, before and after the introduction of a high-pressure balloon catheter (Conquest). Results: The initial success rate was 97%, and re-obstruction was noted in 9 patients in 7 of whom recanalization was achieved by hydro-PTA. The primary patency rate at 1, 3, 6 and 12 months were 91.9%, 59.4%, 29.7%, and 16.2% in the Conquest group, and 75%, 40%, 15%, and 5% in the non-Conquest group. There were significant differences in both groups (p<0.05). Early restenosis or occlusion was often observed in patients with marked stenosis at the venous anastomosis site. Complications were observed in 4 patients: bleeding at the sheath puncture site after dialysis in 1, mild vascular rupture due to overdistension in 1, and re-obstruction due to recoil in 2 patients. However, we did not encounter any pulmonary embolism, which was our greatest concern. The mean time until restenosis was 79.3 days before and 146.7 days after the introduction of a high-pressure balloon, showing significant prolongation after its introduction (p<0.05). Conclusions: Hydro-PTA was useful in artificial graft occlusion. Presently, the level of patient satisfaction is high, and the procedure can be considered as the first treatment of choice for shunt obstruction. However, evaluation of how to prolong further the period until restenosis is necessary.
