Fibromuscular dysplasia of the renal artery: Management and outcome

SUMMARY: Renovascular hypertension may be caused by atherosclerotic disease or less commonly by fibromuscular dysplasia (FMD) of the renal arteries. Fibromuscular dysplasia is the commonest cause of renal artery stenosis in the younger age group and affects women predominantly. A review of our clinical database identified all patients with renovascular hypertension. All relevant clinical, biochemical and radiological findings on those with FMD were noted. the outcome of percutaneous transluminal renal angioplasty (PTRA) or reconstructive surgery was evaluated. Eight out of 62 (13%) patients with hypertension secondary to renovascular disease had FMD (all female; bilateral in four; mean age at diagnosis 37.6 years; age range 12–70 years). the mean duration of hypertension before the diagnosis of FMD was 3.3 years (range 3 months-10 years). A renal artery bruit was detected in five, hypertensive retinopathy in three and one had mild renal insufficiency. Twelve PTRAs were attempted on 10 stenotic lesions in six women. This cured the hypertension in three, while the other three have required less antihypertensive therapy. Percutaneous transluminal renal angioplasty was complicated by a trivial renal artery dissection in one, and a small upper pole infarction in another. One patient required a repeat PTRA. the other two women presented before the availability of PTRA and had successful reconstructive surgery. Fibromuscular dysplasia was the cause of hypertension in eight out of 62 (13%) patients with renovascular hypertension. Percutaneous transluminal renal angioplasty has shown encouraging results with a low complication rate. If technically feasible, PTRA should be attempted on all patients with FMD of the renal artery.     

Percutaneous transluminal renal angioplasty

Summary Percutaneous transluminal renal angioplasty (PTRA) is a simple, efficient procedure with a low risk/benefit ratio when carried out by experienced interventional radiologists. The role of radiology in the diagnosis and treatment of renovascular hypertension (RVH) is discussed, with special attention to technique. PTRA and surgical results are dependent on the etiology and location of renal artery stenosis (RAS). At New York Hospital-Cornell Medical Center, PTRA is the procedure of choice in fibromuscular dysplasia (FMD), unilateral non-ostial atheroma, arteritis, renal transplantation, and pediatrics. The choice between surgery and PTRA in patients with bilateral and ostial atherosclerotic disease and/or azotemia depends on the surgical risk category of the patient. At our institution, coronary and cerebrovascular disease do not preclude PTRA.     

Percutaneous Therapy for Renal Artery Fibromuscular Dysplasia

Fibromuscular dysplasia (FMD) accounts for 10% of cases of renal artery stenosis. This study evaluates the anatomic and functional outcomes of endovascular therapy for symptomatic renal artery FMD at an academic medical center. A retrospective analysis of records from patients who underwent percutaneous transluminal renal artery angioplasty (PTRA) found 14 patients (all female) who underwent 19 interventions on 18 renal artery segments. Significant cardiovascular comorbidities were few in this patient population. The PTRA technical success rate was 95%. There were no periprocedural mortalities. Primary patency rates were 81%, 69%, 69%, and 69% at 2, 4, 6, and 8 years. Assisted primary patency rates were 87%, 87%, 87%, and 87% at 2, 4, 6, and 8 years. The restenosis rate was 25% at 8 years. Clinical benefit (improved or cured hypertension) was seen in 79% of patients overall; 65% of patients maintained this benefit at 8 years by life-table analysis. Percutaneous endovascular intervention for clinically symptomatic FMD of the renal arteries is technically successful, safe, and durable. Most patients demonstrate immediate clinical benefit and retain durable functional outcomes. Presented at the Thirteenth Annual Winter Meeting of the Peripheral Vascular Surgery Society, Snowmass, CO, January 31-February 2, 2003.     

Percutaneous Balloon Angioplasty of Renovascular Hypertension in Pediatric Cases

Purpose : To investigate effectiveness of percutaneous transluminal renal angioplasty (PTRA) in treatment of renal artery stenoses due to Takayasu arteritis (TA), fibromuscular dysplasia (FMD) and neurofibromatosis (NF). Materials-methods : Between December 1991-October 2006, 20 pediatric cases (age range 3–18 years, meanly 12.5 year) with at least 60% stenoses were underwent PTRA. Main presenting symptom was hypertension. The aetiologies were TA in 12, and FMD in 5, NF in three cases.

Results : Totally, 46 procedures were performed on 35 stenotic segments of 20 cases. A technically good result was obtained in 21/24 arteries of TA patients, 7/7 arteries of FMD patients, and 1/3 arteries of NF1 patients. Clinical follow-up for a mean of 55.7 months revealed 100% success in all cases. Delayed clinical response was seen in two cases with Nf1. Restenosis was detected 5/12 of TA patients, 1/5 of FMD patients and 1/3 NF1 patients.

Conclusion : PTRA can be safely performed resulting in excellent angiographic and clinical results. It should be first choice in renal artery stenosis in pediatric age when medical treatment fails to control renovascular hypertension or renal function is decreasing although initial results might be not encouraging in NF1.     

Percutaneous transluminal angioplasty for renovascular hypertension in children

Percutaneous transluminal angioplasty (PTA) has been developed over the past 8 years as an alternative to reconstructive surgery for renovascular hypertension. We report three cases and review the use of PTA in children with renal artery stenosis. At least 37 cases of PTA have been reported in patients whose ages ranged from 1.3 to 17 years (mean 10 years). Of these, 10 had fibromuscular dysplasia; 13 unspecified unilateral renal artery stenosis; 4 bilateral stenosis; 4 neurofibromatosis; 4 renal transplant; 1 atherosclerosis; and 1 postsurgical stenosis. Nine of 10 patients with fibromuscular dysplasia were cured and 3 of 4 with renal transplant arterial stenosis were cured or improved. There were 11 failures of PTA, including all 4 patients with neurofibromatosis and 1 with transplant arterial stenosis. We conclude that PTA is the treatment of choice for children with hypertension due to fibromuscular dysplasia and should be attempted for stenosis of the transplanted renal artery. Other lesions resulting in renal artery stenosis may not be as amenable to dilation and should be considered on an individual basis.R. L. Chevalier is an Established Investigator of the American Heart Association     

Surgical and radiological management of renovascular hypertension in a developing country

PURPOSE: We determined the long-term outcome of radiological and surgical intervention in young patients with renovascular hypertension. MATERIALS AND METHODS: Between 1989 and 2001, 85 patients with a mean age +/- SD of 21 +/- 10.3 years, including 59 with Takayasu's arteritis (TA) and 26 with fibromuscular dysplasia (FMD), underwent radiological (percutaneous transluminal angioplasty) or surgical treatment for renovascular hypertension due to renal artery stenosis. The technical success, complications and clinical response of each treatment were compared. RESULTS: Of the patients 29 with TA and 20 with FMD underwent a total of 56 balloon angioplasties. Technical success was achieved in 94.58 renal units with a clinical response in 41 patients (83.9%). However, the re-stenosis rate was 24.13% in TA and 10% in FMD cases. A total of 41 surgical procedures were performed in the 28 and 7 patients with TA and FMD, respectively, including aortorenal bypass with vein in 12, and with a polytetrafluoroethylene graft in 4, lienorenal bypass in 4, iliorenal bypass in 2, gastroduodenal bypass in 1, autotransplantation in 1, nephrectomy in 14 and partial nephrectomy in 2. The clinical response rate to renal revascularization procedures was 94.4%, whereas it was only 50.0% for nephrectomy/partial nephrectomy during a median followup of 42 months (range 9 to 96). CONCLUSIONS: Percutaneous transluminal angioplasty and renal revascularization provide comparable long-term results in the management of renal artery stenosis due to TA and FMD. Although it is technically complex, surgery for TA is safe and effective. However, the rate of re-stenosis following angioplasty for TA is higher compared with FMD.     

Reno-vascular hypertension in childhood: a nationwide survey

Renovascular disease accounts for 8–10% of all cases of paediatric hypertension, whereas, in adults, its incidence is approximately 1%. The Turkish Paediatric Hypertension Group aimed to create the first registry database for childhood renovascular hypertension in Turkey. Twenty of the 28 paediatric nephrology centres in Turkey responded to the survey and reported 45 patients (27 girls, 18 boys) with renovascular hypertension between 1990 and 2005. The age at presentation ranged from 20 days to 17 years. The mean blood pressure at the diagnosis was 169/110 mmHg. Chief complaints of symptomatic patients were headache (38%), seizure (18%), epistaxis (4%), growth retardation (4%), cognitive dysfunction (4%), polyuria (2%), palpitation (2%), and hemiplegia (2%). Renovascular hypertension was found incidentally in 11 children. The diagnosis of renovascular hypertension was established with conventional angiography in 39 patients, MR angiography in three, CT angiography in two, and captopril diethylene triamine penta-acetic acid (DTPA) scintigraphy in one patient. Twenty-one children had bilateral renal artery stenosis and 24 had unilateral renal artery stenosis. Of these, 14 (31%) had fibromuscular dysplasia; 12 (27%) Takayasu’s arteritis; six (13%) neurofibromatosis; two (5%) Williams syndrome; one (2%) Kawasaki disease; one (2%) mid-aortic syndrome; one (2%) extrinsic compression to the renal artery, and eight (18%) unspecified bilateral renal artery stenosis. Hypertension was controlled with antihypertensive drugs in 17 patients. Percutaneous transluminal angioplasty (PTRA) or surgery had to be performed in 28 patients: PTRA in 16 patients, PTRA + surgery in one patient and surgery in 11 patients (four nephrectomies). The importance of vasculitic disease, especially Takayasu’s arteritis, should not be underestimated in children with renovascular hypertension.     

Surgical renal artery reconstruction after percutaneous transluminal angioplasty

Percutaneous transluminal renal angioplasty (PTRA) is a controversial treatment for renal artery stenosis. This article discusses whether or not a prior attempt at PTRA compromises a subsequent elective or emergent surgical revascularization. Thirteen patients had surgical renal artery reconstruction after one or more PTRAs. Eight of the patients were treated because of atherosclerotic renal artery disease whereas five had a form of fibromuscular dysplasia. Five patients had renal artery injury directly related to the angioplasty. Four of these kidneys were saved. Eight patients were treated from 6 to 920 days after PTRA because of recurrent stenosis or occlusion of the renal artery. Only one of these kidneys was lost, an attempt at revascularization of a small kidney that failed to resume function. A prior attempt at PTRA did not compromise the ability of subsequent surgical revascularization to ameliorate hypertension. We conclude that surgical renal revascularization is not made less likely to succeed by a previous attempt at PTRA; even if the renal artery is thrombosed or perforated during the procedure, a reasonable chance of renal salvage is obtained by immediate surgical revascularization.     

Cause of primary vaginal hydrocele and ascites in advanced liver cirrhosis

The use of percutaneous transluminal angioplasty as the primary treatment of renovascular stenosis in adults has recently been described. Previously, only three children have been reported to have undergone transluminal angioplasty for stenosis of the renal artery and hypertension. At our hospital, transluminal angioplasty was attempted in four children with renal artery stenosis; one attempt was successful and three were unsuccessful. The three patients who required surgical repair of the renal artery after unsuccessful transluminal angioplasty have been described in detail. The histopathology of the stenotic vessels is also discussed. Based on the analysis of the three children, certain criteria have been derived to select pediatric patients with renovascular hypertension either for attempted transluminal angioplasty or for primary surgical revascularization.     

Treatment of renal artery fibromuscular dysplasia with balloon angioplasty: a prospective follow-up study.

OBJECTIVES: to assess restenosis rates and blood pressure response after percutaneous transluminal renal angioplasty (PTRA) in patients treated for fibromuscular dysplastic renal artery stenosis. METHODS: a prospective 12-month follow-up study of 27 patients with 31 treated renal artery stenosis. Follow-up assessment included colour-coded duplex sonography (CCD) of renal arteries, monitoring of blood pressure, antihypertensive medication, and creatinine measurements before discharge and at 3, 6, and 12 months. Primary end point was defined as a haemodynamically significant restenosis >60% assessed by CCD. RESULTS: there was a cumulative 23% restenosis rate at 12 months. Arterial hypertension was cured or improved in 93% of patients immediately after the intervention and remained cured/improved in 74% of patients at 12 months of follow-up. Renal failure present in five patients before PTRA stabilised or improved in all patients. CONCLUSION: although restenosis rate after PTRA in fibromuscular dysplasia is as high as in non-ostial atherosclerotic lesions, there remains a considerable higher therapeutic effect. Profound pressure response and recurrent arterial hypertension with restenosis support the high probability of a renovascular origin of arterial hypertension in this young and otherwise healthy population compared to patients with atherosclerotic renal artery lesions.     

An 8-month-old boy with congenital fibromuscular dysplasia presenting with shock caused by sudden renal hemorrhage

Fibromuscular dysplasia (FMD) is a non-atheromatous, non-inflammatory, multifocal segmental angiopathy. FMD is the most common cause of pediatric renovascular hypertension. Aneurysmal formation of the main renal artery and distal branches is a rare complication of FMD in infancy. We report an 8-month-old boy with FMD presenting with shock caused by sudden renal hemorrhage that necessitated removal of one kidney. A diagnosis of renovascular hypertension resulting from intimal type FMD with aneurysmal formation was made on the basis of the presence of hypertension, elevation of PRA and aldosterone activity, pathological findings and the results of renal angiography. Our findings suggest that it is therefore necessary to consider FMD with aneurysmal formation as a possible cause of hypertension and renal hemorrhage in infants.     

Clinical outcome and health care costs in renal revascularization--percutaneous transluminal renal angioplasty versus reconstructive surgery.

Clinical outcome and health care costs related to investigation, treatment with either percutaneous transluminal renal angioplasty (PTRA) or reconstructive surgery, and follow-up of patients with renovascular hypertension with or without uraemia were analysed in 21 PTRA-treated and 16 operated patients. Most renal artery stenoses were atherosclerotic. Nineteen PTRAs were successful or partly successful and two failed; the patients were operated on without delay. All surgical reconstructions were successful. In the PTRA group six restenoses occurred after 4-24 months. Four were treated with re-PTRA and two were operated on. No recurrence occurred in the operated group. At the end of follow-up (median 48, range 9-84 months) primary patency in the PTRA group was 69 per cent and in the operated group 100 per cent. Secondary patency in the PTRA group was 100 per cent. With regard to hypertension, including primary and secondary results, 19 out of 21 (90 per cent) patients were improved in the PTRA group and 13 out of 16 (81 per cent) in the operated group. The diagnostic and preprocedure costs were the same in both groups, whereas the procedure and postprocedure costs were lower in the PTRA group. However, the follow-up costs were considerably higher because of recurrences and their treatment in the PTRA group. The total median cost of reconstructive surgery was 12 per cent higher than for PTRA, a non-significant difference.     

Transluminal vascular stent implantation for a patient with renovascular hypertension due to renal artery stenosis

In recent years, transluminal vascular stents have been implanted in patients with renal artery stenosis. At present, controversy remains as to whether the long-term outcome of stent implantation is better than that of percutaneous transluminal renal angioplasty (PTRA). However, until now, no clinical experience of a stent placement for renal artery stenosis has been reported in our country. We implanted a Palmaz stent in a patient with renovascular hypertenstion due to renal artery restenosis who had already undergone PTRA. The renal function and blood pressure of the patient improved remarkably.     

Diagnosis, management, and future developments of fibromuscular dysplasia

Fibromuscular dysplasia (FMD) is a nonatherosclerotic noninflammatory vascular disease that primarily affects women from age 20 to 60, but may also occur in infants and children, men, and the elderly. It most commonly affects the renal and carotid arteries but has been observed in almost every artery in the body. FMD has been considered rare and thus is often underdiagnosed and poorly understood by many health care providers. There are, however, data to suggest that FMD is much more common than previously thought, perhaps affecting as many as 4% of adult women. When it affects the renal arteries, the most common presentation is hypertension. When it affects the carotid or vertebral arteries, the patient may present with transient ischemic attack or stroke, or dissection. An increasing number of patients are asymptomatic and are only discovered incidentally when imaging is performed for some other reason or by the detection of an asymptomatic bruit. FMD should be considered in the differential diagnosis of a young person with a cervical bruit; a "swishing" sound in the ear(s); transient ischemic attack, stroke, or dissection of an artery; or in individuals aged ≤ 35 years with onset hypertension. Treatment consists of antiplatelet therapy for asymptomatic individuals and percutaneous balloon angioplasty for patients with indications for intervention. Patients with aneurysms should be treated with a covered stent or open surgical repair. Little new information has been published about FMD in the last 40 years. The recently instituted International Registry for Fibromuscular Dysplasia will remedy that situation and provide observational data on a large numbers of patients with FMD.     

Renal Transplantation for Fibromuscular Dysplasia

This is the first report that presents renal transplantation after bilateral nephrectomy as the final treatment for severe renovascular hypertension due to fibromuscular dysplasia (FMD). We describe the history of a 1‐year‐old girl who suffered from renovascular hypertension due to FMD. Imaging revealed multiple bilateral stenoses of the renal artery extending into the distal branches. The hypertension proved unresponsive to pharmacologic treatment and the intrarenal peripherally located stenoses rendered a conventional approach such as transluminal or surgical angioplasty not feasible. At the age of 5 years, a unilateral nephrectomy of the most affected kidney was performed, but she remained hypertensive and developed progressive cardiomyopathy and retinopathy. At the age of 6 years the remaining kidney was removed, followed by a living related renal transplantation with a kidney donated by her mother. Posttransplantation, she developed mild hypertension due to a postanastomotic stenosis, which was easily controlled with antihypertensives. Now 8 years after transplantation, she has experienced no further blood pressure related problems. Although there is a risk of recurrence of FMD after performing a living related transplantation, our report suggests that this procedure is relatively safe, provided appropriate preoperative evaluation and follow up is performed.     

Percutaneous transluminal renal artery dilatation for fibromuscular dysplasia with special reference to the acute effects on the renin-angiotensin-aldosterone system and blood pressure

Twelve hypertensive patients (mean age 46.6 years, range 37-55 years) with fibromuscular dysplasia of the renal artery were treated with percutaneous transluminal renal angioplasty (PTRA) and the effects on the renin-angiotensin-aldosterone system and blood pressure were studied in the acute phase. The technical result of PTRA measured by angiography and reduction of PRA and aldosterone excretion was satisfactory in 11 patients. In spite of this only three patients were cured of their hypertension and two patients were improved at six months follow-up. During PTRA an immediate rise in plasma renin activity was noted in patients without beta-receptor blockade but not in patients treated with beta-receptor blocking agents suggesting a beta-receptor mediated release. This peak in renin release was not accompanied by any rise in systemic blood pressure. The blood pressure response in the acute phase did not show any regular pattern. We conclude that PTRA can serve as a model for studying effects of 'clamping' and 'declamping' of the renal artery in man.     

Angioplasty of the renal artery: antihypertensive and renal effects

Percutaneous transluminal angioplasty of the renal artery (PTRA) has been increasingly used over the past 20 years for treating renovascular hypertension (RVH). From the experience gathered so far it is justified to state that this technique is the first choice for patients with fibromuscular renal artery stenosis (RAS) because their cure rate is 50% and 42% improve. In contrast in patients with atherosclerotic RAS the cure rate after PTRA is 8-10% although 40-50% still improve. Since PTRA is associated with a 23% rate of major/minor complications and 30% restenosis (23% requiring stent implantation), it is obvious that in patients with atherosclerotic RAS the decision to attempt this procedure must be taken after careful selection of those who may actually benefit from the dilation. PTRA can be used more extensively for salvaging the function of the ischemic kidney than for treating hypertension because of the progressive nature of the atherosclerotic RAS and the lack of effective agents against such progression. After PTRA 35% of patients have some improvement in renal function and another 35% are stabilized. Yet most studies addressing the renal effects of PTRA suffer the limitation of having used serum creatinine levels as an indicator of glomerular filtration rate (GFR). More recent studies which used radioisotopic techniques to evaluate the changes of GFR induced by PTRA in the stenotic kidney indicate that after a successful procedure the increase is, on average, 8-10 ml/min. Interestingly it appears that this improvement is slower in kidneys of patients with atherosclerotic RAS than in those with fibromuscular RAS.     

Should percutaneous transluminal renal artery angioplasty be applied to ostial renal artery atherosclerosis?

Purpose: The purpose of this study was to review the results of percutaneous transluminal renal artery angioplasty (PTRA) in patients with atherosclerosis to assess safety, anatomic and functional outcome, and differences in outcome between ostial and nonostial lesions.Methods: We used retrospective review of 52 consecutive patients who had undergone attempted PTRA for renal artery atherosclerosis during the calendar years 1987 to 1992.Results: Fifty-two patients had 60 renal arteries on whom PTRA was attempted. The mean age was 68 years. Atherosclerosis was generalized in 81% of the patients. The indication for angioplasty was salvage of functioning renal parenchyma in 81% of patients. Eight patients were undergoing dialysis at the time of attempted PTRA. Five arteries (8%) could not be dilated. There were one cardiac death and two arterial complications requiring surgery within 30 days. Thirty-five percent of patients with available angiograms had an anatomic improvement above a threshold of one stenotic group (30% to 40% diameter improvement), with residual stenosis of less than 50%. Half of patients treated for hypertension had improvement in their hypertension. Overall, there was no change in creatinine levels before and after the procedure. Four of eight patients undergoing dialysis at the time of PTRA were able to discontinue dialysis during follow-up. Four patients (11%) required surgical bypass and five patients (14%) required chronic dialysis during follow-up.Conclusions: Modest success at low risk can be expected from PTRA in a group of patients with severe atherosclerosis. No significant difference in results between ostial and nonostial lesions was noted. (J VASC SURG 1995;21:909-15.)     

Management of atherosclerotic renovascular disease: the effect of renal artery stenting on renal function and blood pressure

In the last few years, renal artery stenting has gradually evolved into one of the most important therapeutic modalities in the management of atherosclerotic renovascular disease. Stenting is nowadays preferred by a steadily increasing number of physicians, not only because of its significant contribution to blood pressure control, but also because of its documented ability to maintain, and even improve, renal function. At the same time, procedure-related morbidity and mortality rates are extremely low, while recurrent stenosis rates have been repeatedly reported to be␣minimal. Percutaneous transluminal renal angioplasty (PTRA) and stenting are nowadays considered by many physicians to be the treatment of choice for atherosclerotic renovascular disease.     

Asymptomatic renal infarction, due to fibromuscular dysplasia, in a young woman with 11 years of follow-up

We report a 27-year-old woman with renovascular hypertension, renal infarction, and hepatic artery aneurysm due to fibromuscular dysplasia. The patient was first noted to have renal artery aneurysm and hepatic artery aneurysm at the age of 17. The renal infarction was asymptomatic and was incidentally detected by magnetic resonance imaging (MRI) examination. Because of the rather peripheral location of the aneurysms, percutaneous transluminal renal artery angioplasty was considered inappropriate. This case suggests the need for long-term and periodical follow-up of patients with fibromuscular dysplasia.