Extra-anatomic renal revascularization in patients with renal artery stenosis and abdominal aortic occlusion

Thirteen patients with atherosclerotic renal artery stenosis and total abdominal aortic occlusion underwent extra-anatomic surgical renal revascularization without aortic replacement. Renal artery stenosis was present unilaterally (n = 2), bilaterally (n = 7), or in a solitary kidney (n = 4). Surgical renal revascularization was indicated for treatment of severe hypertension in all patients and for preservation of renal function in 10 patients. The level of abdominal aortic occlusion was suprarenal (n = 3), perirenal (n = 2), or infrarenal (n = 8). All patients had extensive collateral vascular supply to the lower extremities with absent (n = 7) or mild (n = 6) claudication. Surgical renal ervascularization was achieved with hepatorenal bypass (n = 6), mesenterorenal bypass (n = 4), or splenorenal bypass (n = 3). None of the patients underwent concomitant aortic replacement. There were no operative deaths. Postoperatively, hypertension was improved in 10 patients, unchanged in 2 patients, and worse in 1 patient. Renal function was improved in 8 patients, stable in 2 patients, and worse in 3 patients. After surgical renal revascularization, no patient required aortic replacement, while 1 patient underwent extra-anatomic revascularization of the lower extremities. We conclude that some patients with renal artery stenosis and abdominal aortic occlusion can be managed by surgical renal revascularization alone without a more extensive and potentially hazardous aortic replacement. In these patients, extra-anatomic techniques can allow safe and successful surgical renal revascularization while avoiding surgery on the diseased aorta.     

Renal revascularization by end-to-end anastomosis of the hepatic and renal arteries

From June 1981 to January 1984, 13 patients with atherosclerotic renal artery disease underwent revascularization by end-to-end anastomosis of the hepatic and renal arteries. Renal revascularization was indicated to preserve renal function and/or to treat associated hypertension. An aortorenal bypass was not possible owing to severe aortic atherosclerosis or a prior aortic operation. Right renal revascularization was performed by end-to-end anastomosis of the renal artery to the common hepatic artery in 7 patients, right hepatic artery in 4, left hepatic artery in 1 or gastroduodenal artery in 1. Postoperatively, 2 patients suffered a necrotic gallbladder owing to ischemia and 1 of these patients died. Liver enzymes were elevated immediately postoperatively in 11 patients but returned to normal within 2 weeks in each case. Currently, all 12 surviving patients have normal liver function, well controlled blood pressure and improved renal function. End-to-end anastomosis of the hepatic and renal arteries is an effective method of revascularization but specific measures must be taken to avoid complications of gallbladder ischemia.     

Concomitant renal revascularization with aortic surgery: are the risks of combined procedures justified?

Indications for concomitant renal revascularization during aortic surgery are not well established. Higher mortality and poorer results are often cited. To examine this, all combined aortic and renal revascularization procedures from August 1992 until May 1998 were reviewed. Of 2003 major arterial reconstructions performed on the Vascular Teaching Service, 45 patients (2%) underwent renal revascularization. Of these 31 patients (69%) had combined aortic and renal procedures. Aortic pathology in these 31 patients (54% male, 94% white, median age 64 years) included arterial occlusive disease (n = 21; 47%), abdominal aortic aneurysm (n = 6; 13%), and thoracoabdominal aortic aneurysm (n = 4; 9%). In all 31 cases the patient presented because of the aortic pathology. Indications for concomitant renal revascularization included renovascular hypertension (n = 21; 68%) and preservation of renal function (n = 10; 32%). Renal revascularization procedures included transaortic endarterectomy (n = 23; 74%), renal bypass (n = 7; 23%), and both bypass and endarterectomy (n = 1; 3%). Seven (22%) complications and two (6%) deaths (both patients operated on for renal salvage) occurred perioperatively. Complications included wound infection (n = 2; 6%), postoperative bleeding (n = 1; 3%), respiratory failure (n = 1; 3%), deep venous thrombosis (n = 1; 3%), cerebrovascular accident (n = 1; 3%), and pseudomembranous enterocolitis (n = 1; 3%). All patients either were cured of their hypertension (n = 5; 24%) or were improved (n = 16; 76%) at 3 months. No patient to date operated on for renal salvage progressed to chronic hemodialysis, but mortality was higher after renal revascularization for renal salvage versus hypertension (20% vs. 0; P = 0.034). There was no significant difference in mortality between the combined aortic/renal procedures versus aortic procedures alone. Despite adding complexity, renal revascularization in patients undergoing aortic surgery appears relatively safe and effective. These data favor an aggressive approach toward renal revascularization in selected patients needing aortic surgery.     

Iliorenal bypass: indications and outcomes following 41 reconstructions

Iliorenal bypass is a nonanatomic means of renal revascularization usually performed in high-risk patients. Its efficacy was assessed in this review of 35 patients (17 males and 18 females, two children and 33 adults) ranging in age 8-84 years, who were subjected to 41 iliorenal bypasses at the University of Michigan Hospital during 1975-2003. Renal artery lesions included arteriosclerosis (n = 20), developmental narrowing (n = 10), arterial fibrodysplasia (n = 3), penetrating trauma (n = 1), and aortorenal dissection associated with Marfan disease (n = 1). All patients had hypertension attributed to their renal artery disease. Twenty patients exhibited renal insufficiency (serum creatinine >1.8 mg/dL). Primary reasons for selecting an iliorenal reconstruction over a more conventional open revascularization included advanced aortic arteriosclerosis (n = 9); prior aortoaortic, aortoiliac, or aortofemoral reconstruction (n = 7); a small aortic aneurysm not justifying aortic surgery (n = 6); prior aortorenal surgery (n = 6); congenital abdominal aortic coarctation (n = 4); a hostile retroperitoneum (n = 2); or compromised cardiac status (n = 1). Eleven patients had prior ipsilateral renal artery interventions. Iliorenal bypasses were to the right kidney (n = 20), the left kidney (n = 9), and bilateral (n = 12). Conduits were saphenous veins (n = 29), synthetic prostheses (n = 11), or direct renal artery-iliac artery reimplantation (n = 1). Initial bypass patency was 93%. Follow-up averaged 7.5 years. Three early and six late graft complications resulted in eight secondary operations. The mean preoperative and postoperative serum creatinine of all 35 patients did not vary (1.9 vs. 1.8 mg/dL), although on an individual basis renal function improved in eight, remained stable in 21, and deteriorated in six patients. The series' mean preoperative blood pressure of 180/97 mm Hg decreased postoperatively to 140/78 mm Hg (P < 0.001). Hypertension was cured in three patients, improved in 27, and became worse in four. Antihypertensive medication numbers decreased postoperatively, from a median of three to two (P < 0.0001). Surgical mortality was limited to one patient succumbing from perioperative intestinal infarction. Iliorenal bypass is an effective means of renal revascularization in patients not amenable to more conventional open or transluminal procedures.     

Improved results of vascular reconstruction in pediatric and young adult patients with renovascular hypertension

From 1955 to 1988, 56 patients 21 years old or younger underwent surgical treatment for renovascular hypertension at our clinic. The cause of renal artery disease was fibrous dysplasia in 53 patients, Takayasu's arteritis in 2 or an arterial aneurysm in 1. Bilateral or branch renal artery disease, and extrarenal arterial disease were present in 16, 23 and 11 patients, respectively. The results of 28 patients treated from 1955 to 1977 (group 1) were compared to those of 28 patients treated from 1978 to 1988 (group 2). Hypertension was cured or improved postoperatively in 83% of the patients from group 1 and in 96% from group 2 (p = 0.07). However, this outcome was achieved through surgical revascularization in only 48% of the patients from group 1 compared to 96% from group 2 (p = 0.0002). A multivariate analysis revealed that the only significant variable related to clinical outcome was the era of treatment, which reflects the improved technical efficacy of revascularization during the last decade. Aortorenal bypass and renal autotransplantation have emerged as the preferred revascularization operations. It currently is possible to achieve amelioration of hypertension and preservation of renal function in most young patients with renal artery disease.     

Surgical treatment of renovascular disease in the solitary kidney: results in 43 cases

Renal revascularization was performed on 43 patients with vascular disease involving a solitary kidney. Revascularization was undertaken as treatment for severe hypertension in 35 patients and to preserve renal function in 8. There were 2 operative deaths (4.7 per cent) and 3 major complications (7 per cent). No patient suffered acute renal failure after revascularization. Followup ranges from 6 months to 14 years (mean 6 years). The postoperative serum creatinine is improved in 26 patients (63 per cent), unchanged in 9 (22 per cent) and increased in 6 (15 per cent). Of 35 patients with hypertension the blood pressure is cured in 18 (51 per cent) and improved in 14 (40 per cent); there were 3 (9 per cent) failures. In selected patients with renal artery disease involving a solitary kidney revascularization can provide effective treatment of hypertension and stabilization or improvement of renal function.     

Trends in reconstruction for atherosclerotic renal vascular disease

Twenty-eight patients underwent renal vascular reconstruction for atherosclerotic renal vascular stenosis. Ten patients had therapeutic renal artery reconstruction for isolated renal artery stenosis causing severe hypertension, nine patients had therapeutic renal artery reconstruction for severe hypertension combined with simultaneous aortic reconstruction, and nine patients had prophylactic renal artery reconstruction for renal artery stenosis combined with simultaneous aortic reconstruction. Ninety percent of patients undergoing therapeutic renal revascularization procedures for hypertension were cured or improved. The 10 patients undergoing prophylactic renal artery reconstruction combined with aortic reconstruction had an average 72 percent reduction in the diameter of the vessel. Dacron side grafts sutured to the aortic graft were used for revascularization in each of the patients with prophylactic revascularization and was found to be an expedient means of reconstruction with good patency rates. No increased morbidity or mortality rate was noted in the prophylactic group. We believe that prophylactic revascularization should be carried out in patients with atherosclerotic high-grade stenosis of the renal arteries to prevent hypertension and preserve renal function.     

The occluded renal artery: durability of revascularization

Between 1970 and 1982, 50 patients (38 male and 12 female) underwent revascularization of 51 occluded renal arteries. Ages ranged from 8 to 71 years (mean 54.6 years). Occlusion was caused by atherosclerosis in 43 patients, fibromuscular dysplasia in three, chronic dissection in two, abdominal aortic coarctation in one, and neurofibromatosis in one. Contralateral renal artery occlusive disease occurred in 22 patients. Extrarenal atherosclerosis occurred in 44 patients. Mean preoperative serum creatinine level ranged from 0.5 to 8.4 mg/dl (mean 1.9 mg/dl). No patient required preoperative dialysis. Length of the involved kidney ranged from 8.4 to 14.5 cm (mean 11.5 cm). Indication for renal revascularization was hypertension in 49 patients and preservation of renal function in one. Renal artery bypass was performed in 36 patients, renal artery endarterectomy in six, transaortic endarterectomy in five, and reimplantation of the renal artery in three. Simultaneous revascularization of the contralateral renal artery was performed in 20 patients. There were three operative deaths. At hospital dismissal, hypertension had improved in 45 of 46 patients. Follow-up periods ranged from 4 months to 12 years (mean 50.2 months). Thirty-four patients remained normotensive, five still had less hypertension, and seven became worse. These data demonstrate that revascularization of an occluded renal artery can be effective in controlling hypertension and that this effect is durable in the majority of patients.     

Effect of primary renal disease in patients with renovascular insufficiency

The effect of laboratory evidence of renal parenchymal abnormality on the results of renal revascularization in 83 patients with renovascular hypertension was determined. Primary renal disease (PRD) was defined as an abnormal urinalysis (proteinuria, hematuria, or casts) in the absence of urinary infection, or decreased renal function (elevated serum creatinine level greater than 1.5 mg/dl and/or decreased creatinine clearance). All patients were hypertensive on medical therapy preoperatively. Patients were defined as cured if postoperative diastolic blood pressure (BP) was less than 90 mm Hg on no medication and improved if BP less than 90 mm Hg on medication. Sixty-six patients (80%) were cured or improved following revascularization. Of 45 patients (63%) with evidence of PRD preoperatively, 28 (62%) were cured or improved compared with 33 patients without PRD, of whom all (100%) were cured or improved (p less than 0.001). Each of five patients with transplant renal artery stenosis had two operations; four were cured or improved. The serum creatinine level was elevated preoperatively in 37 cases. Eighteen of the 37 (49%) improved to within normal limits following operation. Fifteen patients had simultaneous bilateral renal artery revascularization, and 12 (80%) were cured or improved. Fourteen patients (17%) had concomitant vascular procedures: aortobifemoral bypass (seven), abdominal aneurysm resection (five), femoral endarterectomy (one), and aortoiliac bypass (one). Twelve of these 15 patients had PRD, and 8 of the 12 (67%) were cured or improved. Only one death occurred in the perioperative period. Thirty-eight patients (46%) had been treated for hypertension for more than 12 months before referral.(ABSTRACT TRUNCATED AT 250 WORDS)     

Use of the thoracic aorta for renal arterial reconstruction

Purpose: Thoracic aortorenal bypass is a new technique for surgical renal revascularization in patients with severe atherosclerosis of the abdominal aorta. In such cases, the thoracic aorta is often free of disease.Methods: From 1989 to 1992, thoracic aortorenal bypass was performed in 23 patients with hypertension, abdominal aortic atherosclerosis, and celiac artery stenosis; in 21 patients, renal artery stenosis was present bilaterally or in a solitary kidney.Results: There was one operative death. Among the remaining 22 patients, hypertension was cured or improved after operation in 19 (86%), and renal function was improved or stable in 21 (95%).Conclusions: Thoracic aortorenal bypass has several advantages and is a useful alternative to abdominal aortic replacement in selected older patients who require renal arterial reconstruction. (J VASC SURG 1994;19:605-9.)     

Simultaneous aortic and renal artery reconstruction

Nine patients presenting with combined aortic and renal artery disease underwent simultaneous infrarenal aortic reconstruction and renal revascularization. Seven patients had aneurysmal and two had occlusive aortic disease in association with unilateral (four cases) or bilateral (five cases) atheromatous renal artery stenosis. The indications for renal revascularization were hypertension (n = 8) refractory to medical treatment or associated with renal functional impairment and chronic renal failure alone (n = 1). Five patients developed postoperative complications with one fatality. Eight patients were followed up for between 7 months and 4 years. Control of blood pressure had improved in six of seven hypertensive patients. Serum creatinine levels were stabilized or had fallen in five patients. Simultaneous aortic and renal artery reconstruction is widely recognized as having a high postoperative morbidity rate but can improve control of hypertension and stabilize renal function in carefully selected patients.     

Renal revascularization for recurrent pulmonary edema in patients with poorly controlled hypertension and renal insufficiency: a distinct subgroup of patients with arteriosclerotic renal artery occlusive disease.

Recurrent pulmonary edema in patients with poorly controlled hypertension and renal insufficiency appears to be a marker of bilateral renal artery occlusive disease. The effectiveness of renal revascularization to prevent recurrent pulmonary edema in this distinct subgroup with renal artery occlusive disease was analyzed in 17 consecutive patients treated at the University of Michigan Hospital between 1984 and 1990. Their mean preoperative blood pressure was 207/110 mm Hg, and mean serum creatinine clearance was 3.8 mg/dl. Pulmonary edema occurred despite evidence of normal ventricular function in 65% of these patients. Bilateral renal artery occlusive disease affected 94% of the patients, and 54% had an occluded renal artery. Renal revascularization was accomplished by iliorenal bypass (41%), aortorenal bypass (29%), endarterectomy (24%), and transluminal angioplasty (6%). Contralateral nephrectomy (41%) and concomitant aortic reconstruction (24%) were also required frequently. No postoperative deaths occurred, and no patient had early postoperative pulmonary edema. Control of hypertension was improved in all patients, two of whom were discharged from the hospital on no antihypertensive medications. Two of the three patients requiring dialysis before operation were able to discontinue dialysis after operation. Late follow-up (mean, 2.4 years) revealed hypertension to be cured in one patient (6%), and improved in 16 patients (94%). Pulmonary edema occurred in one patient during late follow-up. Late follow-up showed renal function (mean creatinine, 1.7 mg/dl) to be improved in 77%, stable in 12%, and worse in two patients; one required dialysis. A single episode of pulmonary edema in a patient with poorly controlled hypertension and renal insufficiency should prompt consideration of this clinical syndrome and early diagnostic angiography.(ABSTRACT TRUNCATED AT 250 WORDS)     

Simultaneous aortic reconstruction and renal revascularization: risk factors and late results in eighty-nine patients

From 1973 through 1984, graft replacement of infrarenal aortic aneurysms (N = 56) or occlusive disease (N = 33) was performed in conjunction with simultaneous renal revascularization in 89 patients. Isolated renal artery stenosis was corrected by unilateral reconstruction in 56 patients (63%), but the remaining 33 (37%) had diffuse involvement that required either bilateral renal artery grafts or unilateral revascularization of solitary kidneys. The incidence of hypertension (greater than 180/90 mm Hg) refractory to preoperative medical therapy (88%), severe coronary disease documented by angiography (40%), and postoperative azotemia (33%) or oliguric renal failure (15%) was significantly higher among patients with bilateral renal artery disease (p less than 0.05). In addition, this group had twice the early mortality rate (15%) of patients having unilateral renal artery lesions (7.1%). During a mean follow-up interval of 37 months, medical control of hypertension was enhanced in 46 of the 80 operative survivors (58%), and renal function improved or remained stable in 63 survivors (79%). Five-year actuarial survival presently is 65% for the entire series, with a cumulative mortality rate of 38% among patients who underwent aneurysm resection (mean age 64 years) in comparison to 15% (p = 0.03) for those patients with aortoiliac occlusive disease (mean age 60 years).     

Renal revascularization in high-risk patients: The role of iliac renal bypass

Between 1984 and 1989, 29 iliac renal artery bypasses were performed in 29 patients (mean age 67.8 years) with severe renovascular disease due to atheroma. The indication for renal artery reconstruction was hypertension in all patients, which was associated with kidney failure in 16 cases. In six cases, reconstruction was performed after failure or complications of percutaneous transluminal angioplasty. The bypass was constructed with polytetrafluoroethylene in 24 cases (83%) and vein graft in five cases (17%). There was no postoperative mortality. All bypasses were found to be patent on duplex scanning or digital subtraction arteriograms. One patient was lost to follow-up. Mean follow-up was 23.2 months. One patient died of acute kidney failure, probably related to occlusion of the bypass. Hypertension improved in 22 cases (79%), was cured in two cases (7%), and remained unchanged in four (14%). Renal function remained unchanged in six cases (40%) and improved in nine (60%). Iliac-to-renal artery bypass seems to be the surgical renal revascularization modality best adapted to high-risk patients or those who have severe atheroma. Additionally, this technique enables rapid treatment of failures or complications of percutaneous transluminal angioplasty of the renal artery.Presented at the Annual Meeting of the Société de Chirurgie Vasculaire de Langue Française, May 18–19, 1990, Nancy, France.     

The Contemporary Role of Extra-anatomical Surgical Renal Revascularization in Patients with Atherosclerotic Renal Aretery Disease

We delineate the current role of extra-anatomical revascularization techniques in the treatment of patients with atherosclerotic renal artery stenosis. There are 2 components to this study. In part 1 all abdominal aortograms performed between 1989 and 1993 were reviewed to document the presence of significant abdominal aortic and visceral arterial atherosclerosis in patients with atherosclerotic renal artery stenosis. A total of 254 patients with atherosclerotic renal artery stenosis was identified. Among 44 patients with severe unilateral disease the incidence of significant abdominal aortic atherosclerosis was 75 percent. The incidence of significant (greater than 50 percent) stenosis of the celiac, right common iliac and left common iliac arteries was 52 percent, 32 percent and 27 percent, respectively. In 129 patients with severe atherosclerotic renal artery stenosis bilaterally or in a solitary kidney the incidence of significant abdominal aortic atherosclerosis was 81 percent, and the incidence of significant (greater than 50 percent) stenosis of the celiac, right common iliac and left common iliac arteries was 59 percent, 57 percent and 59 percent, respectively. These data indicate that hepatorenal, splenorenal and iliorenal bypass cannot be performed in many patients with atherosclerotic renal artery stenosis due to significant disease involving the donor vessels for these operations.

In part 2, all patients undergoing surgical renal revascularization with an extra-anatomical bypass operation between 1980 and 1992 were reviewed. A total of 175 operations was done in 171 patients, including hepatorenal bypass in 59, splenorenal bypass in 54, iliorenal bypass in 37, thoracic aortorenal bypass in 23, renal autotransplantation in 1 and superior mesentero-renal bypass in 1. There were 5 operative deaths (2.9 percent) and 7 cases of postoperative graft thrombosis (4 percent). All patients with poorly controlled hypertension were cured or improved postoperatively. Among patients with ischemic nephropathy, postoperative renal function improved in 35 percent, remained stable in 47 percent and deteriorated in 18 percent. Extra-anatomical techniques remain an important component of the surgical armamentarium for atherosclerotic renal artery stenosis. Thoracic aortorenal bypass is a useful new approach in patients with significant celiac and iliac occlusive disease.     

Use of the hepatic circulation for renal revascularization

Aortorenal bypass is the preferred procedure for renal revascularization. Occasionally the aorta cannot be used safely and an alternative procedure is required. Thirty-six patients (21 from the Lahey Clinic and 15 from the Cleveland Clinic) have undergone hepatorenal bypass procedures when confronted with a difficult aorta and right renal artery stenosis. Twenty men and 16 women were operated on and observed from 1 to 9 years. The medical indications for surgery were uncontrollable hypertension in 14 patients, preservation of renal function in eight patients, and a combination of these entities in 14 patients. The surgical indications that required an alternate bypass were diffuse atherosclerotic aortic disease in 24 patients, abdominal aortic aneurysms in six patients, and previous aortic surgery in six patients. Postoperative hepatic function studies were assessed in all patients. No permanent abnormalities of liver function were attributed to surgery. Hypertension was cured or improved in 93% of patients; 7% were unresponsive. Mean creatinine levels were 3.5 mg/dl before operation and 2.1 mg/dl after operation. Renal revascularization was successful in 33 of 36 patients (92%).     

Follow-up of renal artery stenosis by duplex ultrasound

We have previously shown that duplex ultrasound is an accurate method of diagnosing renal artery stenosis (93% accuracy compared with angiography in the diagnosis of less than 60% stenosis, 60% to 99% stenosis, or occlusion). With this method we have now serially observed 35 renal arteries with 60% to 99% renal artery stenosis in 27 patients. Nineteen stenotic renal arteries in 15 patients were observed without intervention. There was a significant decrease in kidney size (mean difference - 1.0 cm; p less than 0.01; mean follow-up 13 months) but all 19 renal arteries remained patent. Percutaneous transluminal angioplasty (PTA) was performed in five patients (six renal arteries) for renovascular hypertension. Renal duplex scanning documented relief of renal artery stenosis in two patients whose hypertension improved after PTA and confirmed residual 60% to 99% renal artery stenosis in three patients whose hypertension did not improve after PTA (mean follow-up 6.5 months). Aortorenal bypass was performed for 10 stenotic renal arteries in seven patients. At a mean follow-up of 9 months duplex ultrasound documented eight patent and two occluded aortorenal bypass grafts. Duplex ultrasound is useful both for defining the natural history of untreated renal artery stenosis and assessing the results of renal artery angioplasty or bypass.     

Angioplasty does not affect subsequent operative renal artery revascularization

BACKGROUND: Although increased application of percutaneous renal artery angioplasty and stenting has facilitated nonoperative renal revascularization, patient outcomes after failed angioplasty are not established. METHODS: Renal artery revascularization was performed in 31 patients (38 arteries) from 1993 to 1999. Twenty patients underwent primary surgical repair, and 11 patients underwent secondary reconstruction after angioplasty (n = 7) or angioplasty and stenting (n = 4). Before operation, all patients had severe hypertension (blood pressure 166+/-5.2/92 +/- 2.7 mm Hg) that required an average of 3.0 +/- 0.2 medications for control. In addition, 12 patients (primary 45% vs secondary 27%; P = NS) had evidence of renal insufficiency (creatinine > or =1.7 mg/dL). RESULTS: There was no difference between primary and secondary procedures in the length of hospital stay (12+/- 1.4 vs. 12+/-3.2 days; P = NS), major morbidity (10% vs. 18%; P = NS) or perioperative mortality (overall mortality 2 of 31; primary 5% vs secondary 9%; P = NS). The majority of patients demonstrated improvement or cure of hypertension (primary 94% vs secondary 90%; P = NS) and stable or decreased creatinine (primary 74% vs secondary 82%; P = not significant). Overall survival (mean follow-up 22+/-3.5 months) was 89%+/-5.7%. CONCLUSIONS: Although this surgical series does not address the true outcomes of renal artery angioplasty, the results suggest that renal artery angioplasty does not prejudice subsequent surgical outcomes in patients who are carefully followed after angioplasty.     

Long-term outcome after surgical kidney revascularization for fibromuscular dysplasia and atherosclerotic renal artery stenosis

PURPOSE: At a time of minimally invasive surgery in urology, the role of surgical kidney revascularization in the management of renal artery disease has changed during the last decade. Our experience with surgical kidney revascularization, and the long-term clinical outcomes of fibromuscular dysplasia (FMD) and atherosclerotic renal artery stenosis are reviewed. MATERIALS AND METHODS: The study group comprised 140 patients with renovascular hypertension, 72 with FMD and 68 with atherosclerotic renal artery disease, who underwent surgical revascularization between 1982 and 1999. The indications for surgical revascularization were the treatment of hypertension and the preservation of renal function in 17 patients with renal artery occlusion, 55 with ostial stenosis, 52 with branch stenosis, 6 with bilateral artery stenosis, 7 with solitary kidney renal artery stenosis and 3 with solitary kidney renal artery occlusion. RESULTS: Postoperative blood pressure and renal function were monitored for 1 to 17 years (mean 11.3). Long-term blood pressure control was observed in 93% of patients with FMD and in 71% of those with atherosclerosis. Improvement or stabilization of renal function was observed in 92% of patients with FMD and in 68% of those with atherosclerosis. The preoperative estimated glomerular filtration rate compared to postoperative was significantly increased in both groups. CONCLUSIONS: Surgical kidney revascularization is effective in secondary hypertension with a high long-term efficacy in the normalization of blood pressure and in the preservation of renal function, especially in patients with a solitary or 1 functional kidney.     

Captopril renal scintigraphy--an advance in the detection and treatment of renovascular hypertension

Despite the risks associated with renovascular hypertension and the durable benefits of revascularization, the detection of patients with renovascular hypertension and the selection of those who will benefit from interventional therapy remains a challenge. We have previously documented the reliability of captopril renal scintigraphy in predicting angiographically significant renal artery stenosis in patients suspected of having renovascular hypertension. In the present study we report our recent experience with this noninvasive technique in predicting outcome after revascularization. Captopril renal scintigraphy involves the administration of 50 mg of captopril 3 hours after a baseline technitium-99m diethylenetriaminepentaacetic acid renal scan and 1 hour before a repeat captopril renal scintigraphy scan. Nineteen of the last 70 patients with clinically suspected renovascular hypertension undergoing captopril renal scintigraphy had abnormal renal scan outcomes, and 17 had a decrease in flow or function after captopril (positive captopril renal scintigraphy). Eight of these 17 with abnormal findings on captopril renal scintigraphy underwent revascularization, and the hypertension was cured or improved in six of the eight: two of three after surgical bypass grafting and four of five after angioplasty. In the seven surviving patients with abnormal renal scan results but no change with captopril (negative captopril renal scintigraphy), improvement in hypertension after treatment occurred in only one: one of two after nephrectomy, zero of three after bypass surgery, and zero of two after angioplasty (p less than 0.05). We conclude that captopril renal scintigraphy is an accurate predictor of hypertension response to revascularization. Further evaluation of this new noninvasive technique for assessing patients with suspected renovascular hypertension appears warranted.