Transluminal angioplasty in patients with bilateral renal artery stenosis or renal artery stenosis in a solitary functioning kidney

Renal artery stenting in solitary functioning kidneys: Technical and clinical results

OBJECTIVE

To evaluate the clinical and technical results of renal artery stenting for the treatment of renovascular hypertension and renal failure in patients with solitary functioning kidney.

MATERIALS AND METHODS

Fifteen patients with solitary functioning kidney underwent renal artery stenting and were followed up for 12-60 months. Before the procedures, systolic and diastolic blood pressures and serum creatinine levels were measured and the number of antihypertensive drugs was recorded and followed up after stenting. In case of restenosis, either in-stent percutaneous transluminal renal angioplasty or stent-in-stent placement was performed.

RESULTS

Primary technical success rate was 100%. One lesion was nonostial while 14 were ostial. Primary patency rates were 100% for 6 months, 92.3% for 12 months, and 69.2% for 24 months. The secondary patency rate at 24 months was 100%. The differences between the baseline and postprocedural values of systolic blood pressures, diastolic blood pressures and the number of antihypertensive drug were statistically significant (P < 0.05), except the values of serum creatinine. Hypertension was cured in 1 (6.7%) patient, improved in 4 (26.6%) and stabilized in 10 (66.7%) patients. Renal function improved in 9 (60%), stabilized in 4 (26.6%), and deteriorated in 2 (13.4%) patients. Minor complication rate was 13.4% and major complication rate was 13.4%.

CONCLUSION

Revascularization of renal artery stenosis using stent in solitary functioning kidneys is a safe and efficient procedure with high primary technical results, low restenosis rates and acceptable complication rates. It has an improving and controlling effect on blood pressure and renal functions.

Atherosclerotic renal arterial stenosis: clinical outcomes of stent placement for hypertension and renal failure

PURPOSE

To assess technical success rates and long-term clinical outcomes of primary renal arterial stent placement in atherosclerotic renal arterial stenosis (RAS).

MATERIALS AND METHODS

Primary stent placement was performed in 100 consecutive patients with atherosclerotic RAS. Indications for treatment were resistant hypertension (n = 25), impaired renal function, (n = 50), and both (n = 25). Immediate technical results were evaluated with angiography. Clinical outcomes were assessed with serial systolic and diastolic blood pressure and serum creatinine values obtained from retrospective review of case notes. Results obtained every 6 months after the procedure were compared with those obtained at the time of the procedure with the paired t test. Radiologic reports were evaluated for immediate and case notes for delayed complications.

RESULTS

Technical success was achieved in 120 (95.2%) of 126 RAS in 95 patients. Mean follow-up was 25 months (median, 24 months; range, 1-66 months). Resistant hypertension was cured in two (4.2%) of 48 patients, had improved in 38 (79.1%), and had failed to respond to treatment in eight (16.7%). Mean systolic and diastolic blood pressures were significantly lower at 6, 12, 18, 24, and 30 months (P <.01) than before the procedure. Among 65 patients treated for renal impairment, renal function improved in 20 (30.8%), stabilized in 25 (41.7%), and continued to deteriorate in 20 (30.8%). The mean serum creatinine level did not show significant change with time for this group. In the improved subgroup, it was significantly higher at 6, 12, 18, 24, 36, and 42 months (P <.05) than prior to the procedure. Procedure-related complications occurred in 18 (18%) cases: Ten were minor and self-limiting and eight were major and included two procedure-related deaths.

CONCLUSION

In atherosclerotic RAS, primary stent deployment has a high technical success rate, producing clinical benefits in the majority of patients when performed for resistant hypertension and recovery of renal function.

Endovascular revascularization of renal artery stenosis in the solitary functioning kidney

The treatment of renal artery stenosis by angioplasty and stenting is an effective and accepted alternative to surgery for the treatment of renovascular hypertension and preservation of renal function. We report the technical and clinical outcomes of renal artery stenting in patients with a solitary functioning kidney and renal artery stenosis. From October 1993 to November 1999, 30 stents were placed in the renal arteries of 27 patients (mean age 72+/-8 years) with a solitary functioning kidney and azotemia. The mean diameter renal artery stenosis was 86+/-14%. The mean preprocedure serum creatinine (Cr) level was 3.0+/-1.5 mg/dL (range 1.5-7.5 mg/dL), arterial blood pressure was 171+/-29/85+/-13 mmHg, and the number of antihypertensive drugs was 2.9+/-1.1. Indications for stenting were suboptimal balloon dilation (n = 16), intimal dissection (n = 6), and restenosis following angioplasty (n = 5). Atherosclerotic ostial lesions were present in 25 (93%) of 27 renal arteries. This represents the largest series of renal artery stenting in patients with a solitary functioning kidney, and demonstrates this treatment modality to be a relatively safe alternative to conventional surgery in this high-risk patient group. Most (74%) of the patients in this series had improved or stabilized renal function. Further efforts to define preprocedural indicators of success are necessary to identify the patients who may benefit from revascularization of their solitary kidney.

Renal artery stenosis treated with stent deployment: indications, technique, and outcome for 108 patients

From January 1993 to May 1996, 108 patients (64 men, 44 women; mean age, 72 years; age range, 37 to 87 years) underwent 125 percutaneous transluminal angioplasties and stent implantations primarily for atherosclerotic lesions of the renal artery. Sixty-four patients underwent treatment for renovascular hypertension (two antihypertensive medications or more), 32 patients underwent treatment for a combination of hypertension and renal failure (serum creatinine level >/=1.6 mg/dL), and a small group of six patients (5%) without hypertension or diminished renal function underwent treatment to prevent the progression to renal artery occlusion and kidney loss. Thirty-three patients (31%) had renovascular hypertension that was classified as severe on three or more medications, 31 patients (29%) had renovascular hypertension that was classified as moderate on two medications, and 38 patients (35%) had renovascular hypertension that was classified in the mild group on a single antihypertensive agent. Stenotic lesions were located at the ostium of the renal artery in 82 cases (65%) and were ostial-adjacent (<5 mm from renal ostium) in the other 43 cases (34%). A total of 125 stents were deployed in 125 arteries (procedural success 97.6%). Renovascular hypertension either was cured or was improved in 73 patients (68%), with 14 patients (13%) considered cured (normotensive on no medications). The conditions of 29 patients (27%) were unchanged, and 6 patients (5%) had worsening hypertension after surgery. We were unable to demonstrate a statistically significant improvement in serum creatinine levels after renal artery balloon angioplasty/stenting. Complications occurred in a total of nine cases (7.2%), six of which were related to technical problems. One patient had worsening renal insufficiency caused by contrast agent, and another patient had a perinephric hematoma develop that necessitated evacuation. There were four postoperative deaths (30-day mortality). Two of these deaths were caused by postoperative myocardial infarction. The other two patients had progressive renal failure develop that necessitated dialysis. These patients later died of the disease process despite supportive care. Follow-up renal artery duplex scan studies and angiograms were available on 96 patients (76%). The mean peak systolic renal/aortic ratio on duplex scanning was 2.2. Life-table analysis yielded a 74% primary patency rate and an 85% secondary patency rate at 36 months. This retrospective analysis showed the effectiveness of combining percutaneous transluminal angioplasty with stent deployment for significant renal artery stenosis to treat renovascular hypertension.

Salvage of the solitary kidney by insertion of a renal artery stent

OBJECTIVE

The purpose of the study was to evaluate the use of renal artery stents in the solitary functioning kidney of patients who have impaired renal function as a result of atherosclerotic renovascular disease by assessing primary patency, renal function outcome, and complication rates during a mean follow-up period of 15 months.

MATERIALS AND METHODS

The Palmaz stent was placed in the arteries of 21 patients with solitary functioning kidneys. All patients had impaired renal function (creatinine level >150 micromol/l), and four patients were undergoing renal dialysis. Indications for stenting were recoil after percutaneous transluminal angioplasty (n = 12), arterial dissection after angioplasty (n = 2), restenosis after angioplasty (n = 1), and as the primary intervention (n = 6). Follow-up angiography was performed in 16 patients (76%).

RESULTS

Initial technical success was achieved in all patients (residual stenosis, <5%). At follow-up (range, 6-25 months), renal function had returned to normal in five patients (24%), improved in four patients (19%), stabilized in six patients (29%), and deteriorated in six patients (29%). Dialysis has been discontinued in all four dialysis patients. Major complications occurred in four patients (19%), including one death within 30 days of stenting. No significant restenoses were seen on follow-up angiography.

CONCLUSION

Placement of renal artery stents in the solitary kidney led to benefits in 70% of patients treated, including improved renal function in nine patients (43%) and stabilization in six patients (29%). In this high-risk group of patients, we advocate renal artery stenting as a relatively safe procedure to salvage the solitary kidney.