Have we new therapeutic strategies in the treatment of renovascular nephropathy?

Renal artery stenosis (RAS) is a cause of hypertension and ischemic nephropathy. The incidence of this disorder is probably less than 1% in patients with mild hypertension, but rises to as high as 10 to 40% in patients with acute, severe or refractory hypertension. Significant RAS can be caused by atheromatous plaques, or due to fibromuscular dysplasia (FMD). Atherosclerotic lesions are present in almost 7% of adults older than 65 years and up to 50% of patients presenting with diffuse atherosclerotic disease. In contrast to atherosclerosis, FMD most often affects women under the age of 50 and typically involves the distal main renal artery or the intrarenal branches. The optimal treatment for RAS is not yet established. Based on recent trials, we reviewed the literature on pharmacological and endovascular treatment of atherosclerotic RAS and ischemic nephropathy.

Low-contrast medium doses for ultrasound imaging during renal revascularization by PTA-stenting.

BACKGROUND: To evaluate the incidence of progressive renal damage in patients with chronic renal insufficiency and renal-artery stenosis undergoing percutaneous transluminal angioplasty and stenting (PTA-stenting), color Doppler ultrasound (CDU)-guided, a procedure requiring low-contrast medium doses, or digital subtraction angiography were compared. METHODS: Thirty patients with renal artery stenosis and severe renal insufficiency underwent PTA-stenting for revascularization, 15 patients with CDU guidance and 15 patients with standard selective digital subtraction angiography (SDSA). Serum creatinine (Cr) concentrations were compared in the two groups at 6 days and 12 months after revascularization. RESULTS: The stents were properly positioned and resolved the renal artery stenosis. None of the patients who underwent ultrasound-guided PTA-stenting had significantly increased Cr values (>50% or >1 mg/dL) at 6 days after surgery (95% confidence interval (95% CI), 0-21.8); and none had progressive chronic renal insufficiency at 12 months. Conversely, six of the 15 patients in the group who underwent PTA-stenting with standard SDSA had significantly increased Cr values at 6 days (95% CI, 16.3-67.7) and two patients had progressive chronic renal insufficiency at 12 months. CONCLUSIONS: Our results suggest that PTA-stenting under CDU guidance, a procedure requiring low-contrast medium doses, is suitable for patients with severe renal dysfunction and especially for those with diabetes mellitus undergoing percutaneous renal revascularization.

Color Doppler ultrasound guidance during renal angioplasty and stenting.

PURPOSE: To investigate whether an imaging technique combining color Doppler ultrasonography and selective renal artery digital subtraction angiography reduces contrast requirements in patients with progressive renal insufficiency undergoing renal artery angioplasty and stenting. METHODS: Eight patients (5 men; mean age 58 years) with renal artery stenosis and renal insufficiency underwent percutaneous transluminal angioplasty and stenting under color Doppler ultrasound guidance. RESULTS: Color Doppler ultrasound imaging yielded the information necessary for verifying catheter position, stent placement and expansion, and hemodynamics after revascularization. The combined imaging technique considerably reduced contrast requirements to only 10 mL in each case. No worsening of renal function was seen in any patient. CONCLUSIONS: The combined imaging procedure uses low doses of contrast agent and is especially suited to patients with renal dysfunction undergoing percutaneous renal revascularization.