Renal duplex sonography after treatment of renovascular disease

To define the value of renal duplex sonography (RDS) to detect the presence of critical renal artery (RA) stenosis or occlusion after surgical repair or percutaneous transluminal balloon angioplasty (PTRA), we retrospectively reviewed our recent 71-month experience.

From January 1987 through November 1992, 272 patients underwent 279 operative RA repairs and 35 patients underwent PTRA. Three hundred twenty-five RDS examinations were performed in 176 patients after operative intervention or PTRA during the study period. Forty-one of these patients had conventional angiography providing 61 RA for RDS comparison, and these data form the basis of this analysis. Twenty-four women and 17 men (mean age 57 years) underwent 44 operative RA repairs or 17 PTRA for correction of atherosclerotic disease (51 arteries) or fibromuscular dysplasia (10 arteries). Before their renovascular procedure each patient had significant hypertension (mean 193/106 mm Hg). RDS after surgery or PTRA was technically complete for all 61 RA.

Compared with angiography RDS correctly identified 47 of 48 repairs with less than 60% RA stenosis , 7 of 11 repairs with 60% to 99% stenosis, and 2 renal artery occlusions, providing a 69% sensitivity rate, 98% specificity rate, 90% positive predictive value, and a 92% negative predictive value. These results were adversely affected by branch RA disease, which accounted for three of four false-negative RDS study results. For 50 kidneys undergoing correction of main RA disease, RDS demonstrated an 89% sensitivity rate, 98% specificity rate, and 96% overall accuracy. RDS results were equivalent for both surgical and PTRA treatment.

From this experience we conclude that RDS is useful for anatomic evaluation after surgical RA repair or PTRA. A negative RDS result excludes stenosis or occlusion of a main RA reconstruction but does not exclude significant branch level disease.