Predictors of arteriovenous graft patency after radiologic intervention inhemodialysis patients

Arteriovenous grafts in hemodialysis patients are prone to recurrent stenos is and thrombosis, requiring frequent radiologic and surgical interventions to optimize their long-term patency. Little is known about the factors tha t determine graft outcome after a radiologic intervention. The present stud y examined the clinical and radiologic predictors of intervention-free graf t survival after elective angioplasty or thrombectomy. A prospective comput erized database was used to determine the outcomes subsequent to all graft angioplasties (n = 330) and thrombectomies (n = 326) performed at the Unive rsity of Alabama at Birmingham between April 1, 1996, and June 30, 1999. Pr imary graft survival rates after angioplasty and thrombectomy were 86% vers us 43% at 1 month, 71% versus 30% at 3 months, 51% versus 19% at 6 months, and 28% versus 8% at 12 months, respectively. The median intervention-free graft survival time was substantially longer after angioplasty than thrombe ctomy (6.7 versus 0.6 months; P < 0.001). The superior outcome of angioplas ty over thrombectomy was observed even for the subset of procedures with no residual stenosis (median survival, 6.9 versus 2.5 months; P < 0.001), The median graft survival was inversely related to the magnitude of residual s tenosis for both elective angioplasty and thrombectomy. Median intervention -free graft survival after angioplasty was inversely related to the postang ioplasty intragraft to systemic systolic pressure ratio (7.6, 6.9, and 5.6 months for ratios <0.4, 0.4 to 0.6, and >0.6, respectively; P < 0.001). Int ervention-free graft survival after angioplasty or thrombectomy was not aff ected by graft location (forearm versus upper arm), number of stenotic site s, or presence of diabetes. In conclusion, graft survival is substantially longer after elective angioplasty than thrombectomy, even when the radiolog ic appearance after the procedure suggests complete resolution of the steno tic lesion. Moreover, the risk for requiring a subsequent graft interventio n can be predicted from two simple radiologic measurements: grade of stenos is and intragraft to systemic systolic blood pressure ratio. These paramete rs may help determine the frequency of monitoring for recurrent stenosis in a given graft. (C) 2001 by the National Kidney Foundation, Inc.