P0163EPIDEMIOLOGY OF FMD: A REVIEW OF THE SALFORD EXPERIENCE
Authors: De Bhailis Aine , Chrysochou Tina 
Published: June 2020

Background and Aims

Fibromuscular dysplasia (FMD) is a non-atherosclerotic, non-inflammatory disease of medium arteries that has been described in multiple vascular beds from cranial to pelvic with a wide variety of manifestations such as beading, stenosis, occlusion, aneurysm or dissection.

Both the United States and European Registries for FMD have made significant contributions to our understanding of FMD however many questions remain. To date those with a diagnosis of FMD within the UK have not been captured within any such registry. The RaDaR ( National registry of rate kidney diseases ) FMD group in Salford Royal NHS Foundation Trust aims to recruit UK based patients to a national registry, which will align with the European registry to facilitate collaboration and future research.

Salford Royal Trust is unique as it has the only dedicated FMD clinic in the UK. This clinic aims to effectively diagnose screen and treat those with suspected FMD. Here we describe the experience of a dedicated clinic for those with FMD, the first of its type in the United Kingdom.

Method

Screening of all electronic patient records from January 2010 to October 2019 was undertaken for diagnosis of fibromuscular dysplasia, coronary artery dissection, middle aortic syndrome along with the acronyms “SCAD” and “FMD”. This search yielded 36 patients with a possible relevant diagnosis. Incidence, clinical characteristics, risk factors and treatment modalities were reviewed.

The diagnosis had to be confirmed in the vascular bed by angiography, either computed tomographic angiography (CTA) or magnetic resonance angiography reviewed by experienced radiologist. FMD was diagnosed as non-atherosclerotic arterial stenosis affecting the trunk or branch of medium sized vessels, in the absence of aortic wall thickening, inflammation and known syndromic arterial disease

The diagnosis of SCAD was made based on coronary angiographic characterised by a tear in the arterial wall that is nontraumatic and non-iatrogenic with no secondary aetiology of the dissection

Clinical data collected included:

Results

From January 2010 to September 2019 36 patients were identified using the pre-specified search terms. 9 patients were excluded leaving 27 patients with a diagnosis of FMD, SCAD or middle aortic syndrome.

The median age was 50 with a 2:1 ratio for females to males.

The majority of patients with FMD (17/20) presented with a renal manifestation i.e. hypertension.

Renal artery FMD was confirmed by CTA/MRA in 20 patients. Of these 60% had extra-renal screening. 11 patients had cerebral screening (8 CTA and 6 MRAs). 7 patients had aortic imaging (4 CTAs, 4 MRAs). Only 6 of the 12 had head to toe screening.

In terms of secondary prevention 50% of those with an FMD diagnosis were on a statin and 45% were on an anti-platelet agent.

In relation to those with an initial diagnosis of SCAD (5), 3 patients had screening in terms of CTA/MRA and 1 patient was found to have cerebral vessel manifestations consistent with FMD.

Conclusion

A dedicated clinic for FMD allows for prompt diagnosis and appropriate screening for possible involvement of other vascular beds. It also allows appropriate treatment with secondary prevention agents such a to those who are most likely to benefit. Although in its infancy there is great potential for this bespoke clinic to continue to expand to become a national centre of excellence.