Cerebrovascular fibromuscular dysplasia: The MGH cohort and literature review

Vessel Wall Imaging Features of Spontaneous Intracranial Carotid Artery Dissection

BACKGROUND AND OBJECTIVES

Intracranial dissection is an important cause of stroke often with nonspecific angiographic features. Vessel wall imaging (VWI) can detect dissections, but intracranial applications remain unvalidated by pathologic specimens. We sought to determine the ability of VWI to identify the rarely reported spontaneous intracranial carotid dissection (sICD) guided by postmortem validation.

METHODS

VWI features of sICD, validated by postmortem specimen analysis in 1 patient, included luminal enhancement within a hypoenhancing outer wall, narrowing the mid to distal ophthalmic (C6) segment, relatively sparing the communicating (C7) segment. VWI examinations were reviewed to identify patients (1) with matching imaging features, (2) no evidence of other vasculopathies (i.e., inflammatory, intracranial atherosclerotic disease [ICAD]), and (3) adequate image quality. These sICD VWI features were compared with those in patients with known ICAD causing similar narrowing of C6 and relative sparing of C7 by a Fisher exact test accounting for multiple samples.

RESULTS

Among 407 VWI examinations, 8 patients were identified with 14 sICDs, all women aged 30-56 years, 6 (75%) bilateral. All patients with sICD had risk factors of dissection (e.g., recently postpartum, fibromuscular dysplasia, and hypertension) and 3 (37.5%) had intracranial dissections elsewhere. Seven (87.5%) were diagnosed as moyamoya syndrome on initial angiography. Enhancing lesions varied from thin flap-like defects (n = 6) to thick tissue along the superolateral wall of the internal carotid artery, within the hypoenhancing outer wall. Compared with 10 intracranial carotid plaques in 8 patients with ICAD, sICD demonstrated stronger (84.6% vs 20.0%, p = 0.003-0.025) and more homogeneous (61.5% vs 0.0%, p = 0.005-0.069) enhancement and less positive remodeling (0.0% vs 60.0%, p = 0.004-0.09). T1 hyperintensity was identified in 5 sICDs in 3 patients but not identified in ICAD. Three patients with serial imaging (8- to 39.8-month maximum intervals) revealed little to no changes in stenosis, wall thickening, or enhancement.

DISCUSSION

sICD is distinguishable on VWI from ICAD by enhancement characteristics, less positive remodeling, and clinical parameters. These VWI features should raise suspicion especially in young women with risk factors of dissection. Temporal stability and a lack of T1 hyperintensity should not discourage diagnosing sICD.

Cerebral arteriopathies of childhood and stroke - A focus on systemic arteriopathies and pediatric fibromuscular dysplasia (FMD)

Systemic vascular involvement in children with cerebral arteriopathies is increasingly recognized and often highly morbid. Fibromuscular dysplasia (FMD) represents a cerebral arteriopathy with systemic involvement, commonly affecting the renal and carotid arteries. In adults, FMD diagnosis and classification typically relies on angiographic features, like the 'string-of-beads' appearance, following exclusion of other diseases. Pediatric FMD (pFMD) is considered equivalent to adult FMD although robust evidence for similarities is lacking. We conducted a comprehensive literature review on pFMD and revealed inherent differences between pediatric and adult-onset FMD across various domains including epidemiology, natural history, histopathophysiology, clinical, and radiological features. Although focal arterial lesions are often described in children with FMD, the radiological appearance of 'string-of-beads' is highly nonspecific in children. Furthermore, children predominantly exhibit intimal-type fibroplasia, common in other childhood monogenic arteriopathies. Our findings lend support to the notion that pFMD broadly reflects an undefined heterogenous group of monogenic systemic medium-or-large vessel steno-occlusive arteriopathies rather than a single entity. Recognizing the challenges in categorizing complex morphologies of cerebral arteriopathy using current classifications, we propose a novel term for describing children with cerebral and systemic vascular involvement: 'cerebral and systemic arteriopathy of childhood' (CSA-c). This term aims to streamline patient categorization and, when coupled with advanced vascular imaging and high-throughput genomics, will enhance our comprehension of etiology, and accelerate mechanism-targeted therapeutic developments. Lastly, in light of the high morbidity in children with cerebral and systemic arteriopathies, we suggest that investigating for systemic vascular involvement is important in children with cerebral arteriopathies.

Intrinsic stenosing and occlusive pathologies of the vertebral artery: A narrative review

Intrinsic pathologies of the vertebral arteries, such as atherosclerosis, dissection, fibromuscular dysplasia, radionecrosis and vasculitis, are important causes of vertebrobasilar insufficiency and cerebrovascular events. This review focuses on non-aneurysmal intrinsic stenosing and occlusive pathologies, covering their epidemiology, diagnosis, and treatment options. It also provides a detailed summary of key clinical presentations and syndromes, including an in-depth examination of lateral medullary syndrome, historically known as Wallenberg's syndrome, which is arguably the most emblematic condition resulting from vertebral artery involvement and is depicted in an illustrative cartoon.

Prevalence and outcomes of select rare vascular conditions in females: A descriptive review

Rare vascular conditions frequently pose a diagnostic and therapeutic dilemma for health care providers. Several of these conditions have distinct relevance to females populations but, due to their infrequency, there has been little reported on the outcomes of rare vascular conditions specifically in females populations. We performed a literature review of a selection of three rare vascular conditions known to either disproportionately affect females (median arcuate ligament syndrome and fibromuscular dysplasia) or have unique manifestations in females populations (vascular Ehlers-Danlos syndrome). We performed a descriptive review of the literature focused on these three vascular conditions and identified aspects of the current available research describing sex-based differences in prevalence, any pathophysiology explaining the observed sex-based differences, and the contribution of sex to outcomes for each disease process. In addition, considerations for pregnant females with respect to each rare vascular disease process are discussed.

Cerebrovascular Fibromuscular Dysplasia - A Practical Review

Fibromuscular dysplasia (FMD) is a rare idiopathic, segmental, noninflammatory and nonatherosclerotic arteriopathy of medium-sized arteries. It is classically considered to be a disease of young and middle adulthood, with females more commonly affected than males. FMD is a systemic disease. Although historically considered to be rare, cerebrovascular FMD (C-FMD) has now been recognized to be as common as the renovascular counterpart. Extracranial carotid and vertebral arteries are the most commonly involved vascular territories in C-FMD with the clinical presentation determined by vessels affected. Common symptoms include headaches and pulsatile tinnitus, with transient ischemic attacks, ischemic stroke and subarachnoid or intracerebral hemorrhage constituting the more severe clinical manifestations. Cervical artery dissection involving carotids more often than vertebral arteries and intracranial aneurysms account for the cerebrovascular pathologies detected in C-FMD. Our understanding regarding C-FMD has been augmented in the recent past on account of dedicated C-FMD data from North American, European and other international FMD cohorts. In this review article, we provide an updated and comprehensive overview on epidemiology, clinical presentation, etiology, diagnosis and management of C-FMD.

Spontaneous coronary artery dissection: an uncommon primary presenting feature of fibromuscular dysplasia

Spontaneous coronary artery dissection is a rare but increasingly recognised cause of acute coronary syndrome particularly in young women, accounting for up to 25% of acute coronary syndrome cases in women under 50. It is, however, an uncommon primary presenting pathology of underlying fibromuscular dysplasia. We present the case of a woman in her 40s, with no significant medical history, presenting with anterior ST elevation myocardial infarction, identified as spontaneous coronary artery dissection on invasive coronary angiogram with an underlying aetiology, and subsequent diagnosis, of fibromuscular dysplasia being established on MR angiography.

Casper stent in the treatment of pulsatile tinnitus in fibromuscular dysplasia: Therapeutic review and case report

Fibromuscular dysplasia (FMD) is a known cause of pulsatile tinnitus that can, on rare occasion, evolve into an incapacitating condition. It is a noninflammatory and nonatherosclerotic arteriopathy of unknown cause that affects medium-sized vessels, such as the carotid and renal arteries, occurring mainly in women. We describe a 72-year-old woman suffering from pulsatile tinnitus refractory to medical treatment who was successfully treated with Casper stent in the carotid artery. The different treatment strategies published in the literature were reviewed.

The Relationship Among Pain Location, Complications, and Quality of Life in Individuals With Fibromuscular Dysplasia

BACKGROUND

Fibromuscular dysplasia (FMD), a nonatherosclerotic arterial disease, can cause pain and vascular complications. The aim of this study was to examine the impact of FMD symptoms and complications on quality of life, depression, anxiety, and self-rated health.

DESIGN

This was a cross-sectional, correlational study.

METHODS

Participants were adults with a diagnosis of FMD. Quality of life (36-Item Short Form Health Survey), anxiety and depression (Patient-Reported Outcomes Measurement Information System [PROMIS®]), self-rated health question, and symptom/complication questionnaires were mailed to patients with FMD. Scores were compared with symptoms and complications. Multivariable linear models were fit for symptoms and survey scores. Ordinal regression was used for self-rated health. Backwards selection was run for each model. Alpha of 0.05 and 95% confidence intervals were used.

RESULTS

Of the 162 (275 total; 47.8%) patients who returned surveys (156 female), 130 had carotid or vertebral artery involvement (80.2%). Migraine (p < .001), neck pain (p = .036), and flank pain (p = .025) were associated with decrease in Mental Component scores. Migraine (p = .002) and neck pain (p = .023) were associated with lower Physical Component scores. Patients reporting abdominal pain compared with those without had 4.88 points higher depression. Abdominal pain (p = .031) and pulsatile tinnitus (p = .011) were associated with greater anxiety. Migraine was associated with (p = .002) lower self-rated health. Participants with history of stroke/transient ischemic attack had 2.42 (1.08, 5.46; p = .033) times the odds of poor self-rated health compared with those without stroke/transient ischemic attack.

CONCLUSIONS

Among patients with FMD, presence of pain and history of vascular complications were related to lower quality of life and self-rated health.

Symptomatic internal carotid artery dissection and kinking in a patient with fibromuscular dysplasia

Isolated dissection of the internal carotid artery (ICA) is rare in young patients and is a cause for strong suspicion of fibromuscular dysplasia (FMD), especially when associated with artery elongation and tortuosity. The natural history of cerebrovascular FMD is unknown and management of symptomatic patients can be challenging. We report the case of a 44-year-old female patient with a history of transient ischemic attack in the absence of cardiovascular risk factors, associated with an isolated left ICA dissection and kinking. Carotid duplex ultrasound confirmed the diagnosis of dissection and demonstrated severe stenosis of the left ICA. The patient underwent surgical repair and histopathological evaluation confirmed the diagnosis of FMD with dissection. An autogenous great saphenous vein bypass was performed and the patient had an uneventful recovery. Cervical carotid artery dissection can be related to underlying arterial pathologies such as FMD, and the presence of ICA tortuosity highlights certain peculiarities for optimal management, which might be surgical.

Male Sex Is Associated With Cervical Artery Dissection in Patients With Fibromuscular Dysplasia

Background Cervical artery dissection (CeAD) is a frequent manifestation of fibromuscular dysplasia (FMD). However, risk factors for CeAD are unknown. We investigated factors associated with CeAD in the ARCADIA (Assessment of Renal and Cervical Artery Dysplasia) registry. Methods and Results The ARCADIA registry includes women or men aged ≥18 years, with a diagnosis of renal, cervical, or intracranial artery FMD, who were prospectively recruited at 16 university hospitals in France and Belgium. Diagnosis of acute or past CeAD at inclusion was established on imaging according to standard diagnostic criteria. Associations between potential determinants and CeAD were assessed by logistic regression analyses. Among 469 patients (75 men) with FMD, 65 (13.9%) had CeAD. Patients with CeAD were younger, more likely to be men, have a history of migraine, and less likely to have a history of hypertension than patients without CeAD. In the multivariable analysis, male sex (odds ratio [OR], 2.66; 95% CI, 1.34-5.25), history of migraine (OR, 1.90; 95% CI, 1.06-3.39), age ≥50 years (OR, 0.41; 95% CI, 0.23-0.73), history of hypertension (OR, 0.35; 95% CI, 0.20-0.64), and involvement of ≥3 vascular beds (OR, 2.49; 95% CI, 1.15-5.40) were significantly associated with CeAD. To validate the association between CeAD and sex, we performed a systematic review. We collected additional data on sex from 2 published studies and unpublished data from the US Registry for Fibromuscular Dysplasia and the European/International FMD Registry. In the pooled analysis (289 CeAD, 1933 patients), male sex was significantly associated with CeAD (OR, 2.04; 95% CI, 1.41-2.95; I²=0%). Conclusions In patients with FMD, male sex and multisite involvement are associated with CeAD, in addition to other previously known risk factors. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02884141.

Prevalence of Cervical Artery Abnormalities on CTA in Patients with Spontaneous Coronary Artery Dissection: Fibromuscular Dysplasia, Dissection, Aneurysm, and Tortuosity

BACKGROUND AND PURPOSE

Little is known about associations between spontaneous coronary artery dissection and cervical artery abnormalities. This study sought to assess the prevalence of cervical artery abnormalities among patients with spontaneous coronary artery dissection.

MATERIALS AND METHODS

A retrospective analysis was completed of patients who underwent CTA neck imaging as part of arterial assessment following the diagnosis of spontaneous coronary artery dissection. The internal carotid and vertebral arteries were evaluated for the presence of fibromuscular dysplasia, dissection and/or pseudoaneurysm, ectasia and/or aneurysmal dilation, atherosclerosis, and webs. Carotid tortuosity was categorized into kinks, loops, coils, and retrojugular and/or retropharyngeal carotid courses; vertebral tortuosity was classified by subjective analysis of severity.

RESULTS

Two hundred fourteen patients were included in the final cohort, of whom 205 (95.8%) were women; the average age was 54.4 years. Fibromuscular dysplasia was the most frequently observed abnormality (83 patients; 38.8%), followed by dissections and/or pseudoaneurysms (n = 28; 13.1%), ectasia and/or aneurysmal dilation (n = 22; 10.3%), and carotid webs (n = 10; 4.7%). At least 1 type of carotid tortuosity was present in 99 patients (46.3%). The majority (n = 185; 86.4%) of patients had no carotid atherosclerosis; and 26 (12.2%) had mild; 3 (1.4%), moderate; and 0, severe carotid atherosclerosis.

CONCLUSIONS

The most common abnormality in the cervical artery vasculature of patients with spontaneous coronary artery dissection is fibromuscular dysplasia. Cervical dissections were higher than previously reported but were not observed in most patients.

[Fibromuscular dysplasia and its neurological manifestations]

The authors present the current data on the classification, epidemiology, etiology, neurological manifestations, prognosis, diagnosis, and treatment of patients with fibromuscular dysplasia (FMD). The review is based on the selection of publications by searching PubMed for keywords from the first sources until March 2019. FMD is a segmental non-atherosclerotic and non-inflammatory disease of large- and medium-caliber arteries leading to their stenosis. The disease occurs mostly in women (90%), and manifests itself in the 5th decade of life. In the cerebrovascular form of FMD, the extracranial internal carotid artery and the vertebral artery are usually affected. Diagnosis is based on the identification of alternation of narrowing and dilation of arteries using angiography (the string of beads sign (multifocal form)). Neurological manifestations include headache, tinnitus, and ischemic stroke, usually due to the dissection or stenosis, rarely, intracerebral or subarachnoid hemorrhages. The prognosis in most cases is favorable, relapses of strokes are rare. Treatment includes antiplatelet agents, if they are ineffective to prevent recurrence of ischemic stroke, endovascular treatment is carried out. Approaches to the treatment of intracranial aneurysms do not differ from those in patients without FMD.

Different clinical courses of various radiologic findings in fibromuscular dysplasia during a 7-year follow-up: A case report

RATIONALES

The natural history of fibromuscular dysplasia (FMD) is unclear. Furthermore, the correlation between radiologic findings and clinical significance has not been documented. Previously, the development of new vascular symptoms was reported in a small number of patients, but some of these symptoms were from other vascular causes. New arterial lesions were rarely observed during follow-up in the previous reports.

PATIENT CONCERNS

A 40-year-old man was admitted due to dysarthria and left-sided weakness. He had developed flank pain due to bilateral renal infarction about 10 months earlier. He had no known risk factors for atherosclerosis. Initial neurological examination revealed a mild weakness and central facial palsy on the left side.

DIAGNOSES

Diffusion-weighted magnetic resonance imaging revealed a small acute infarction in the right insular cortex. Magnetic resonance angiography and digital subtraction angiography showed a severe stenosis with post-dilatation in the right internal carotid artery (ICA). There was a focal ectatic lesion in the left ICA. On the previous abdominal computed tomography angiography (CTA), there were arterial lesions suggestive of dissection in the bilateral renal arteries and a rod-shaped ectasia in the left common iliac artery (CIA). The pathological diagnosis was mixed-type FMD involving the intima and media.

INTERVENTIONS

The patient was prescribed antiplatelet agents for prevention of further ischemic events and followed up regularly.

OUTCOMES

Seven years after the initial renal infarction, the patient developed abdominal pain radiating to the back. Abdominal CTA revealed that an aortic dissection had developed in the infrarenal aorta, which was shown as normal previously. The ectasia in the left CIA and left ICA showed no interval changes during follow-up.

LESSONS

We present a patient who developed spontaneous symptomatic dissection of the bilateral renal arteries, right ICA, and abdominal aorta during 7 years of follow-up, which were caused by pathologically confirmed FMD. Besides the symptomatic multifocal dissection, the patient showed an asymptomatic multifocal ectasia on cerebral and abdominal angiographies that had not changed over 7 years.

Fibromuscular Dysplasia and Its Neurologic Manifestations: A Systematic Review

Importance

Data on neurologic manifestations of fibromuscular dysplasia (FMD) are rare, and current knowledge remains limited.

Objectives

To present a comprehensive review of the epidemiologic characteristics, management, and prognosis of the neurologic manifestations associated with cerebrovascular FMD (ie, involving cervical or intracranial arteries) and to guide future research priorities.

Evidence Review

References were identified through searches of PubMed from inception to December 2017 using both the medical subject headings and text words. Additional sources were also identified by reviewing reference lists of relevant articles and through searches of the authors' personal files. Selected articles described at least 1 clinical or radiologic feature and/or outcome of cerebrovascular FMD. Isolated case reports could be included if they described interesting or noteworthy manifestations of FMD.

Findings

A total of 84 relevant references were identified. Diagnosis of cerebrovascular FMD is based on the appearance of alternating arterial dilatation and constriction ("string of beads") or of focal narrowing, with no sign of atherosclerotic or inflammatory lesions. Although the diagnosis is easily apparent on results of radiographic imaging, making a diagnosis can be challenging in children or individuals with atypical phenotypes, such as purely intracranial FMD and arterial diaphragm. Involvement of multiple arteries is common, and there is increased incidence of cervical artery dissection and intracranial aneurysms. A variant in the PHACTR1 gene has been associated with FMD as well as cervical artery dissection and migraine, although less than 5% of cases of FMD are familial. Headaches, mainly of the migraine type, are observed in up to 70% of patients with FMD. Cerebrovascular FMD is mostly asymptomatic, but the most frequent neurologic manifestations include transient ischemic attack and ischemic stroke, notably in the presence of associated cervical artery dissection. Other conditions associated with FMD include subarachnoid hemorrhage and, rarely, intracranial hemorrhage. Management relies on observational data and expert opinion. Antiplatelet therapy is considered reasonable to prevent thromboembolic complications. Endovascular therapy is typically restricted to cases with symptomatic stenosis despite optimal medical therapy or in those with rupture of an intracranial aneurysm.

Conclusions and Relevance

Longitudinal cohort studies of individuals of multiple ethnicities with biosampling are needed to better understand the risk factors, pathophysiological features, and outcomes of FMD. Patient advocacy groups could assist researchers in answering patient-centered questions regarding FMD.

Prevalence, Presentation, and Associated Conditions of Patients With Fibromuscular Dysplasia

Fibromuscular dysplasia (FMD) is defined by focal narrowing of small and medium-sized arteries due to an idiopathic, noninflammatory, nonatherosclerotic vascular disease. The population-based prevalence of FMD remains unknown. Using the National Inpatient Sample database, we evaluated the prevalence, clinical presentation, mortality, and associated conditions of FMD from January 1, 2004, to September 30, 2015. Among 2,420 patients who presented with FMD, 2,086 (86.20%) of patients were female. The mean age was 55.18 ± 18.99 years in men and 63.37 ± 17.10 years in women. FMD patients most commonly presented with hypertension (67.3%), transient ischemic attack (3.7%), headache (2.1%), dizziness (1.1%), abdominal pain (0.6%), or hematuria (0.3%). In-hospital mortality of FMD patients was 0.74%. In conclusion, FMD is a rare condition with low in-hospital mortality that may be considered among female patients presenting with hypertension.

Endovascular Treatment of Concomitant Carotid Fibromuscular Dysplasia and Atherosclerotic Disease After Failed Open Surgical Treatment

We describe a case of concomitant fibromuscular dysplasia (FMD) and atherosclerotic internal carotid artery (ICA) disease in a symptomatic patient. Sixty-eight-year-old female presented for evaluation of a transient ischemic attack. Imaging revealed severe proximal >80% ICA stenosis with severe FMD to mid and distal ICA. Planned hybrid approach with left carotid endarterectomy (CEA) and balloon angioplasty was aborted intraoperatively due to lack of back bleeding. Open gradual rigid dilation was then performed with resumption of back bleeding. Completion angiogram revealed widely patent flow through CEA patch with no residual defects. Patient awoke from operation neurologically intact. At 6-month follow-up, carotid duplex revealed severe recurrent ICA stenosis. Endovascular intervention was performed with balloon dilation to the proximal and mid-ICA with stenting of a moderate 60% ostial common carotid stenosis. She recovered well from procedure with 3-month carotid duplex showing widely patent common carotid stent and ICA with no areas of stenosis. Informed consent has been obtained from the patient for publication of the case report and accompanying images.

Endovascular management of an acute type B aortic dissection in a patient with fibromuscular dysplasia

We report the case of a 44-year-old woman who developed an acute type B aortic dissection caused by an entry tear from an aneurysmal left common iliac artery that extended retrograde to the proximal descending thoracic aorta. She experienced refractory chest pain despite optimal medical management, thereby indicating repair. Endovascular aortic repair was subsequently performed. Intraoperatively, fibromuscular dysplasia was diagnosed by the characteristic appearance of her renal arteries. The patient tolerated the procedure and had resolution of her chest pain. In summary, we present a highly unusual case of type B aortic dissection resulting from a retrograde common iliac artery tear in a patient with fibromuscular dysplasia.

Tread carefully: A functional variant in the human NADPH oxidase 4 (NOX4) is not disease causing

In this study, we report a paediatric patient with a lethal phenotype of respiratory distress, failure to thrive, pancreatic insufficiency, liver dysfunction, hypertrophic cardiomyopathy, bone marrow suppression, humoral and cellular immune deficiency. To identify the genetic basis of this unusual clinical phenotype and potentially make available the option of future prenatal testing, whole exome sequencing (WES) was used followed by functional studies in a bid to confirm pathogenicity. The WES we identified a homozygous novel variant, AK298328; c.9_10insGAG; p.[Glu3dup], in NOX4 in the proband, and parental heterozygosity for the variant (confirmed by Sanger sequencing). NADPH Oxidase 4 NOX4 (OMIM 605261) encodes an enzyme that functions as the catalytic subunit of the NADPH oxidase complex. NOX4 acts as an oxygen sensor, catalysing the reduction of molecular oxygen, mainly to hydrogen peroxide (H₂O₂). However, although, our functional data including 60% reduction in NOX4 protein levels and a 75% reduction in the production of H₂O₂ in patient fibroblast extracts compared to controls was initially considered to be the likely cause of the phenotype in our patient, the potential contribution of the NOX4 variant as the primary cause of the disease was clearly excluded based on following pieces of evidence. First, Sanger sequencing of other family members revealed that two of the grandparents were also homozygous for the NOX4 variant, one of who has fibromuscular dysplasia. Second, re-evaluation of more recent variant databases revealed a high allele frequency for this variant. Our case highlights the need to re-interrogate bioinformatics resources as they are constantly evolving, and is reminiscent of the short-chain acyl-CoA dehydrogenase deficiency (SCADD) story, where a functional defect in fatty acid oxidation has doubtful clinical ramifications.