Relationship of renal dysfunction to proximal arterial disease severity inatherosclerotic renovascular disease

Background. Renal impairment is common in patients with atherosclerotic ren ovascular disease (ARVD), but its pathogenesis is uncertain. This study inv estigated whether any relationship existed between renal function and the s everity of proximal renal arterial lesions in patients with ARVD. Methods. A cohort of 71 patients had creatinine clearance measured at the t ime of digital subtraction angiography; eight patients were diabetics and w ere excluded from further analysis. The severity of proximal renovascular l esions was estimated by standard methodology, and patients were sub-grouped according to residual patency of the proximal renal arteries (e.g. normal = 2.0; unilateral occlusion (RAO) = 1.0). Renal bipolar lengths at ultrasou nd were also assessed. Results. Sixty-three non-diabetic patients (mean +/- SD age 67.7 +/- 5.8 ye ars; 34 males) were suitable for study. No differences in renal function (m ean +/- SD creatinine clearance (ml/min)) were seen between patients with u nilateral (32.1 +/- 18.9, n = 36) or bilateral (31.7 +/- 20.9, n = 27) dise ase, or between sub-groups with RAS <60% (28.3 +/- 13.9, n = 15), unilatera l RAS >60% (38.9 +/- 24.6, n = 12), bilateral RAS >60% (36.3 +/- 20.4, n = 6) or unilateral RAO (30.3 +/- 17.7, n = 28), and mean average renal size s imilarly did not differ between the sub-groups. No correlation existed betw een residual patency and creatinine clearance (r = 0.015); mean +/- SD rena l function was almost identical in the four patency sub-groups, and average renal size mirrored this pattern. Mean 24-h urinary protein excretion was similar for the four groups, but patients with minimal ARVD had significant ly less comorbid vascular disease. Conclusions. These findings suggest that the severity of proximal renal art ery lesions is often unrelated to the severity of renal dysfunction in pati ents with ARVD. Associated renal parenchymal damage is the more probable ar biter of renal dysfunction, and this should be considered when revasculariz ation procedures are contemplated.