Optimal management of renal artery fibromuscular dysplasia

Abstract

Fibromuscular dysplasia (FMD) is a nonatherosclerotic, noninflammatory angiopathy of unknown cause affecting medium-sized (most commonly renal) arteries and causing renovascular hypertension. The most common medial multifocal type of FMD (with the “string of beads” appearance) is more than four times more prevalent in females than in males. FMD accounts for up to 10% of cases of renovascular hypertension. Compared with patients with atherosclerotic renal artery stenosis, patients with FMD are younger, have fewer risk factors for atherosclerosis, and a lower occurrence of atherosclerosis in other vessels. The etiology is multifactorial, including vessel wall ischemia and smoking, as well as hormonal and genetic factors. Intra-arterial digital subtraction angiography is still the gold standard for exclusion or confirmation of renal artery stenosis caused by FMD, at least in young patients, who more often have lesions in branches of the renal artery. For FMD patients with atherosclerosis and those who are older (>50–55 years), significant renal artery stenosis may be confirmed or excluded with ultrasonography. The FMD lesion is typically truncal or distal, whereas atherosclerotic lesions are more often proximal or ostial. Treatment options are medical, endovascular (percutaneous transluminal renal angioplasty [PTRA]), and surgical. Invasive treatment should be considered when hypertension cannot be controlled with antihypertensive drugs and in patients with impaired renal function or ischemic nephropathy. PTRA has become the treatment of choice and normally yields good results, especially in unifocal disease and young patients. Pressure gradients are normally completely abolished, and there is no indication for stent placement. Surgical revascularization is indicated after PTRA complications; thrombosis, perforation, progressive dissection, repeated PTRA failure or restenosis. Centralization of handling is recommended.

Surgical Renovascular Reconstruction for Renal Artery Stenosis and Aneurysm: Long-Term Durability and Survival

“…Unsatisfactory control of hypertension is generally considered a reason to intervene, and endovascular treatment has gradually become the first choice, whereas surgery is often reserved for patients with complications of PTRA or recurrent stenosis after PTRA. 22 In the present series of patients with FMD, the right renal artery was more commonly affected than the left. That was also the case for RAA.…”

Renal Artery Stenosis As Etiology of Recurrent Flash Pulmonary Edema and Role of Imaging in Timely Diagnosis and Management

“…Limitations include the administration of nephrotoxic radiocontrast and invasive nature due to the need for intra-arterial access. The hallmark feature of the common type of fibromuscular dysplasia, "string of beads" appearance, is detectable on renal angiography [10,18,20,25,[27][28].…”

“…If duplex ultrasound, CTA, and MRA are indeterminate or pose a risk of significant renal impairment, renal angiography is useful for a definitive diagnosis of RAS. Patients with lowerextremity peripheral artery disease or coronary artery disease have a high prevalence of RAS, and as such, obtaining a renal angiogram may be considered in patients in whom there is a high clinical suspicion for RAS and who are known to have coronary artery disease and are undergoing invasive angiography [9][10]18,20,25].…”

“…Multidrug antihypertensive therapy for aggressive control of blood pressure is the mainstay of the treatment. Aggressive lifestyle modification with control of atherosclerotic disease risk factors is an important part of management [10,26,[28][29]. The focus of medical management for RAS relies on controlling renovascular hypertension.…”

“…Balloon angioplasty followed by stent placement yields higher procedural success rate compared to surgical bypass with lower restenosis. In patients with RAS due to fibromuscular dysplasia, balloon angioplasty alone without stent placement is often performed with outcomes comparable to those of stent placement [10][11][12]34].…”