Blood pressure and renal function before and after percutaneous transluminal renal angioplasty in fibromuscular dysplasia: A cohort study

Outcomes Following the Endovascular Treatment of Renal Artery Stenosis Caused by Fibromuscular Dysplasia: A Systematic Review and Meta-Analysis

OBJECTIVE

Renal artery revascularization has been performed to improve blood pressure control and to cure hypertension in patients with renal artery fibromuscular dysplasia (RAFMD). We herein conducted a systematic review and meta-analysis of studies assessing outcomes associated with the treatment of hypertensive RAFMD patients via endovascular angioplasty in order to offer an up-to-date overview of the relative costs and benefits of this approach to revascularization in RAFMD patients.

METHODS

We systematically searched the PubMed and Embase databases and the Cochrane Central Register for Controlled Trials to identify relevant studies published as of January 15, 2020. Key outcomes of interest in these studies included technical success, the incidence of perioperative complications, cure rates, and overall improvement rates.

RESULTS

In total, we identified 36 relevant studies of 1916 total repairs conducted in 1191 patients. Of these included studies, 33 were retrospective, while 3 were prospective. The overall technical success rate across these studies was 94.3%. Rates of total, major, and minor complications in these pooled studies were 12.9%, 4.6%, and 7.4%, respectively. Pooled rates of cured hypertension and improved hypertension following angioplasty, defined according to study-specific criteria, were 37.0% [95% CI: 27.0%-47.0%] and 80.0% [95% CI: 75.0% to 84.0%], respectively, although these rates varied highly among studies. Cure rates for studies used current clinical definitions for substantial variations across studies. Cure rates in studies using current definitions of cured hypertension (blood pressure <140/90 mm Hg without treatment) were just 18.1% following angioplasty. Cure rates fell markedly with increasing mean patient age (OR associated with an increase in mean age of 10 years: -0.24 [95% CI: -0.44 to -0.04, P = 0.019] and with mean known duration of hypertension (OR associated with an increase in mean hypertension duration of 5 years: -0.09 [95% CI: -0.12 to -0.05, P = 0.001]).

CONCLUSIONS

These findings suggest that endovascular treatment yielded moderate benefits to RAFMD patients, with substantial variation across studies. The blood pressure outcome was strongly influenced by patient age.

Clinical characteristics and treatment of renal artery fibromuscular dysplasia with percutaneous transluminal angioplasty: a long-term follow-up study

BACKGROUND

Renal artery fibromuscular dysplasia (RAFMD) is a non-atherosclerotic cause of renal artery stenosis often affecting the young. Percutaneous transluminal renal angioplasty (PTRA) is the treatment of choice but there are few studies of the outcome of the procedure.

METHODS

This retrospective analysis included 64 patients (56.2 % female; mean age at diagnosis, 28.0 years) with RAFMD who underwent PTRA between November 2003 and August 2015. Technical and clinical success rates and restenosis rates were evaluated.

RESULTS

Seventy-six procedures were performed on 64 RAFMD patients. Technical success was 96.9 %, as defined by <30 % residual stenosis, with stent placement required in 11 patients (17.2 %). In the short term (1 month), the majority (79.7 %) had an immediate clinical benefit, with cure of hypertension in 35.9 %, and improvement in hypertension and a lower requirement for antihypertensive medications in 43.8 %. In the long term (mean, 47.5 months; range, 5-141 months), the survival rate was 96.9 %, freedom from restenosis was 84.4 %, and 76.6 % of patients showed a sustained clinical benefit (cure rate 40.6 %, improvement rate 35.9 %). Eight patients were treated with a second procedure and two had a third procedure, with half of these patients showing an improvement in hypertension.

CONCLUSION

PTRA for symptomatic RAFMD is safe and clinically successful. More than half of patients experience an immediate clinical benefit with sustained long-term effects. For patients with restenosis, there was a good response to a second PTRA.

European consensus on the diagnosis and management of fibromuscular dysplasia

The main objectives of this expert consensus are to raise awareness about fibromuscular dysplasia, which is more frequent and more often systemic than previously thought and can sometimes have devastating consequences; to provide up-to-date recommendations for the diagnosis, evaluation, and management of the disease; and to identify research priorities. The emphasis has been put on recommendations for daily practice. The main topics covered include definition, classification, diagnosis, and management of fibromuscular dysplasia in adult patients with symptomatic involvement of the renal arteries, supra-aortic trunks, and digestive and peripheral arteries.

Optimal management of renal artery fibromuscular dysplasia

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.

Renal artery stenosis-when to screen, what to stent?

Renal artery stensosis (RAS) continues to be a problem for clinicians, with no clear consensus on how to investigate and assess the clinical significance of stenotic lesions and manage the findings. RAS caused by fibromuscular dysplasia is probably commoner than previously appreciated, should be actively looked for in younger hypertensive patients and can be managed successfully with angioplasty. Atheromatous RAS is associated with increased incidence of cardiovascular events and increased cardiovascular mortality, and is likely to be seen with increasing frequency. Evidence from large clinical trials has led clinicians away from recommending interventional revascularisation towards aggressive medical management. There is now interest in looking more closely at patient selection for intervention, with focus on intervening only in patients with the highest-risk presentations such as flash pulmonary oedema, rapidly declining renal function and severe resistant hypertension. The potential benefits in terms of improving hard cardiovascular outcomes may outweigh the risks of intervention in this group, and further research is needed.