PHACTR1 Is a Genetic Susceptibility Locus for Fibromuscular Dysplasia Supporting Its Complex Genetic Pattern of Inheritance

Spontaneous coronary artery dissection

Spontaneous coronary artery dissection is an underdiagnosed entity. It has been recognized as an important cause of acute coronary syndrome and sudden death, particularly among young women and individuals with few conventional atherosclerotic risk factors. This document provides an exhaustive review of the pathophysiology and etiology of this disease. In addition, we describe the main clinical characteristics of these patients, the diagnostic tests that must be performed, and the most appropriate treatment.

Current progress in clinical, molecular, and genetic aspects of adult fibromuscular dysplasia

Fibromuscular dysplasia (FMD) is a non-atherosclerotic vascular disease that may involve medium-sized muscular arteries throughout the body. The majority of FMD patients are women. Although a variety of genetic, mechanical, and hormonal factors play a role in the pathogenesis of FMD, overall, its cause remains poorly understood. It is probable that the pathogenesis of FMD is linked to a combination of genetic and environmental factors. Extensive studies have correlated the arterial lesions of FMD to histopathological findings of arterial fibrosis, cellular hyperplasia, and distortion of the abnormal architecture of the arterial wall. More recently, the vascular phenotype of lesions associated with FMD has been expanded to include arterial aneurysms, dissections, and tortuosity. However, in the absence of a string of beads or focal stenosis, these lesions do not suffice to establish the diagnosis. While FMD most commonly involves renal and cerebrovascular arteries, involvement of most arteries throughout the body has been reported. Increasing evidence highlights that FMD is a systemic arterial disease and that subclinical alterations can be found in non-affected arterial segments. Recent significant progress in FMD-related research which has led to improved understandings of the disease's clinical manifestations, natural history, epidemiology, and genetics. Ongoing work continues to focus on FMD genetics and proteomics, physiological effects of FMD on cardiovascular structure and function, and novel imaging modalities and blood-based biomarkers that can be used to identify subclinical FMD. It is also hoped that the next decade will bring the development of multi-centred and potentially international clinical trials to provide comparative effectiveness data to inform the optimal management of patients with FMD.

PHACTR1 genetic variability is not critical in small vessel ischemic disease patients and PcomA recruitment in C57BL/6J mice

Recently, several genome-wide association studies identified PHACTR1 as key locus for five diverse vascular disorders: coronary artery disease, migraine, fibromuscular dysplasia, cervical artery dissection and hypertension. Although these represent significant risk factors or comorbidities for ischemic stroke, PHACTR1 role in brain small vessel ischemic disease and ischemic stroke most important survival mechanism, such as the recruitment of brain collateral arteries like posterior communicating arteries (PcomAs), remains unknown. Therefore, we applied exome and genome sequencing in a multi-ethnic cohort of 180 early-onset independent familial and apparently sporadic brain small vessel ischemic disease and CADASIL-like Caucasian patients from US, Portugal, Finland, Serbia and Turkey and in 2 C57BL/6J stroke mouse models (bilateral common carotid artery stenosis [BCCAS] and middle cerebral artery occlusion [MCAO]), characterized by different degrees of PcomAs patency. We report 3 very rare coding variants in the small vessel ischemic disease-CADASIL-like cohort (p.Glu198Gln, p.Arg204Gly, p.Val251Leu) and a stop-gain mutation (p.Gln273*) in one MCAO mouse. These coding variants do not cluster in PHACTR1 known pathogenic domains and are not likely to play a critical role in small vessel ischemic disease or brain collateral circulation. We also exclude the possibility that copy number variants (CNVs) or a variant enrichment in Phactr1 may be associated with PcomA recruitment in BCCAS mice or linked to diverse vascular traits (cerebral blood flow pre-surgery, PcomA size, leptomeningeal microcollateral length and junction density during brain hypoperfusion) in C57BL/6J mice, respectively. Genetic variability in PHACTR1 is not likely to be a common susceptibility factor influencing small vessel ischemic disease in patients and PcomA recruitment in C57BL/6J mice. Nonetheless, rare variants in PHACTR1 RPEL domains may influence the stroke outcome and are worth investigating in a larger cohort of small vessel ischemic disease patients, different ischemic stroke subtypes and with functional studies.

An Outline of Renal Artery Stenosis Pathophysiology-A Narrative Review

Renal artery stenosis (RAS) is conditioned mainly by two disturbances: fibromuscular dysplasia or atherosclerosis of the renal artery. RAS is an example of renovascular disease, with complex pathophysiology and consequences. There are multiple pathophysiological mechanisms triggered in response to significant renal artery stenosis, including disturbances within endothelin, kinin-kallikrein and sympathetic nervous systems, with angiotensin II and the renin-angiotensin-aldosterone system (RAAS) playing a central and key role in the pathogenesis of RAS. The increased oxidative stress and the release of pro-inflammatory mediators contributing to pathological tissue remodelling and renal fibrosis are also important pathogenetic elements of RAS. This review briefly summarises these pathophysiological issues, focusing on renovascular hypertension and ischemic nephropathy as major clinical manifestations of RAS. The activation of RAAS and its haemodynamic consequences is the primary and key element in the pathophysiological cascade triggered in response to renal artery stenosis. However, the pathomechanism of RAS is more complex and also includes other disturbances that ultimately contribute to the development of the diseases mentioned above. To sum up, RAS is characterised by different clinical pictures, including asymptomatic disorders diagnosed in kidney imaging, renovascular hypertension, usually characterised by severe course, and chronic ischemic nephropathy, described by pathological remodelling of kidney tissue, ultimately leading to kidney injury and chronic kidney disease.

Heart Disease and Stroke Statistics-2021 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2021 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population, an enhanced focus on social determinants of health, adverse pregnancy outcomes, vascular contributions to brain health, the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors related to cardiovascular disease.

RESULTS

Each of the 27 chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

[Molecular genetics of human hypertension]

A genetic influence on blood pressure was demonstrated more than 100 years ago and a simple Mendelian inheritance was initially presumed. Platt and Pickering conducted a lively debate on this topic. Platt favored the idea that a single gene or only a few genes were responsible for high blood pressure. Pickering presented research results, which supported the assumption that many genes exerted an influence on blood pressure. This was all in a period when it was not even known what genes were. Genome-wide association studies (GWAS) according to the Pickering model have identified > 500 blood pressure relevant gene loci, which are distributed over the whole genome. Each individual gene exerts only a small effect on blood pressure. The dark horses of hypertension research are the secondary causes. In pheochromocytoma, primary aldosteronism, Cushing's syndrome and even fibromuscular dysplasia (renovascular hypertension) the results indicate that a genetic cause regularly underlies secondary hypertension. This would therefore also partially confirm Platt's theory. In the meantime, a multitude of forms of hypertension have been described with a genetic inheritance according to Mendel. Each of these genetic variants exerts a considerable influence on blood pressure. A multitude of novel physiological mechanisms were explained by this. These findings will become therapeutically important. Therefore, it is incumbent upon clinicians to be optimally informed about these research results.

Fibromuscular dysplasia: A comprehensive review on evaluation and management and role for multidisciplinary comprehensive care and patient input model

Fibromuscular dysplasia is a nonatherosclerotic, under-recognized disorder primarily seen in middle-aged women. It can lead to several complications, such as hypertension, headaches, dissections, aneurysms, myocardial infarctions, and cerebrovascular accidents, to name a few. This article provides a comprehensive review of current literature on epidemiology, etiology, diagnosis, treatment, and long-term surveillance and fibromuscular dysplasia management. In addition, it renders the role of education and prevention for patients living with this condition and family screening. Lastly, it emphasizes the importance of a comprehensive multidisciplinary care model and patient input, given the complexity of this disease and its systemic presence and protean manifestations.

Spontaneous cervical artery dissection and fibromuscular dysplasia: Epidemiologic and biologic evidence of a mutual relationship

Cervical artery dissection (CeAD) is the most common cause of ischemic stroke in young and middle-aged adults. Over the last decade, a relation between CeAD and fibromuscular dysplasia (FMD), an idiopathic, segmental, non-atherosclerotic and non-inflammatory arterial disease, has been suggested based on a number of epidemiologic observations, while preliminary data support the idea that the two conditions may share common biologic mechanisms. In this article, we review the literature on the relation between CeAD and FMD, focus on the potential pathogenetic mechanisms common to the two conditions, summarize clinical features, management and outcome, and provide support to the hypothesis that the coexistence of the two diseases in one individual might be conceptualized as a distinct non-atherosclerotic non-inflammatory arteriopathy.

Clinical Features of Patients With Cervical Artery Dissection and Fibromuscular Dysplasia

BACKGROUND AND PURPOSE

Observational studies have suggested a link between fibromuscular dysplasia and spontaneous cervical artery dissection (sCeAD). However, whether patients with coexistence of the two conditions have distinctive clinical characteristics has not been extensively investigated.

METHODS

In a cohort of consecutive patients with first-ever sCeAD, enrolled in the setting of the multicenter IPSYS CeAD study (Italian Project on Stroke in Young Adults Cervical Artery Dissection) between January 2000 and June 2019, we compared demographic and clinical characteristics, risk factor profile, vascular pathology, and midterm outcome of patients with coexistent cerebrovascular fibromuscular dysplasia (cFMD; cFMD+) with those of patients without cFMD (cFMD-).

RESULTS

A total of 1283 sCeAD patients (mean age, 47.8±11.4 years; women, 545 [42.5%]) qualified for the analysis, of whom 103 (8.0%) were diagnosed with cFMD+. In multivariable analysis, history of migraine (odds ratio, 1.78 [95% CI, 1.13-2.79]), the presence of intracranial aneurysms (odds ratio, 8.71 [95% CI, 4.06-18.68]), and the occurrence of minor traumas before the event (odds ratio, 0.48 [95% CI, 0.26-0.89]) were associated with cFMD. After a median follow-up of 34.0 months (25th to 75th percentile, 60.0), 39 (3.3%) patients had recurrent sCeAD events. cFMD+ and history of migraine predicted independently the risk of recurrent sCeAD (hazard ratio, 3.40 [95% CI, 1.58-7.31] and 2.07 [95% CI, 1.06-4.03], respectively) in multivariable Cox proportional hazards analysis.

CONCLUSIONS

Risk factor profile of sCeAD patients with cFMD differs from that of patients without cFMD. cFMD and migraine are independent predictors of midterm risk of sCeAD recurrence.

Assessing genomic diversity and signatures of selection in Jiaxian Red cattle using whole-genome sequencing data

Background

Native cattle breeds are an important source of genetic variation because they might carry alleles that enable them to adapt to local environment and tough feeding conditions. Jiaxian Red, a Chinese native cattle breed, is reported to have originated from crossbreeding between taurine and indicine cattle; their history as a draft and meat animal dates back at least 30 years. Using whole-genome sequencing (WGS) data of 30 animals from the core breeding farm, we investigated the genetic diversity, population structure and genomic regions under selection of Jiaxian Red cattle. Furthermore, we used 131 published genomes of world-wide cattle to characterize the genomic variation of Jiaxian Red cattle.

Results

The population structure analysis revealed that Jiaxian Red cattle harboured the ancestry with East Asian taurine (0.493), Chinese indicine (0.379), European taurine (0.095) and Indian indicine (0.033). Three methods (nucleotide diversity, linkage disequilibrium decay and runs of homozygosity) implied the relatively high genomic diversity in Jiaxian Red cattle. We used θπ, CLR, F_ST and XP-EHH methods to look for the candidate signatures of positive selection in Jiaxian Red cattle. A total number of 171 (θπ and CLR) and 17 (F_ST and XP-EHH) shared genes were identified using different detection strategies. Functional annotation analysis revealed that these genes are potentially responsible for growth and feed efficiency (CCSER1), meat quality traits (ROCK2, PPP1R12A, CYB5R4, EYA3, PHACTR1), fertility (RFX4, SRD5A2) and immune system response (SLAMF1, CD84 and SLAMF6).

Conclusion

We provide a comprehensive overview of sequence variations in Jiaxian Red cattle genomes. Selection signatures were detected in genomic regions that are possibly related to economically important traits in Jiaxian Red cattle. We observed a high level of genomic diversity and low inbreeding in Jiaxian Red cattle. These results provide a basis for further resource protection and breeding improvement of this breed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-020-07340-0.

Cerebral aneurysms and cervical artery dissection: Neurological complications and genetic associations

Dissections and aneurysms are two of the more common nonatherosclerotic arteriopathies of the cerebrovascular system and a significant contributor to neurovascular complications, particularly in the young. Specifically, ruptured intracranial aneurysms (IA) account for nearly 500,000 cases of subarachnoid hemorrhage annually with a 30-day mortality approaching 40% and survivors suffering often permanent neurologic deficits and disability. Unruptured IAs require dedicated assessment of risk and often warrant serial radiologic monitoring. Cervical artery dissection, affecting the carotid and vertebral arteries, accounts for nearly 20% of strokes in young and middle-aged adults. While approximately 70% of cervical artery dissection (CeAD) cases present with stroke or TIA, additional neurologic complications include severe headache and neck pain, oculosympathetic defect (i.e., partial Horner's syndrome), acute vestibular syndrome, and rarely lower cranial nerve palsies. Both aneurysms and dissections of the cerebrovascular system may occur frequently in patients with syndromic connective tissue disorders; however, the majority of cases are spontaneously occurring or mildly heritable with both polygenic and environmental associations. Fibromuscular dysplasia, in particular, is commonly associated with both risk of CeAD and IA formation. Further research is needed to better understand the pathophysiology of both IA and CeAD to better understand risk, improve treatments, and prevent devastating neurologic complications.

Extracellular Matrix in Vascular Disease, Part 2/4: JACC Focus Seminar

Medium-sized and large arteries consist of 3 layers: the tunica intima, tunica media, and tunica adventitia. The tunica media accounts for the bulk of the vessel wall and is the chief determinant of mechanical compliance. It is primarily composed of circumferentially arranged layers of vascular smooth muscle cells that are separated by concentrically arranged elastic lamellae; a form of extracellular matrix (ECM). The tunica media is separated from the tunica intima and tunica adventitia, the innermost and outermost layers, respectively, by the internal and external elastic laminae. This second part of a 4-part JACC Focus Seminar discusses the contributions of the ECM to vascular homeostasis and pathology. Advances in genetics and proteomics approaches have fostered significant progress in our understanding of vascular ECM. This review highlights the important role of the ECM in vascular disease and the prospect of translating these discoveries into clinical disease biomarkers and potential future therapies.

[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.

A Novel Recurrent COL5A1 Genetic Variant Is Associated With a Dysplasia-Associated Arterial Disease Exhibiting Dissections and Fibromuscular Dysplasia

OBJECTIVE

While rare variants in the COL5A1 gene have been associated with classical Ehlers-Danlos syndrome and rarely with arterial dissections, recurrent variants in COL5A1 underlying a systemic arteriopathy have not been described. Monogenic forms of multifocal fibromuscular dysplasia (mFMD) have not been previously defined. Approach and Results: We studied 4 independent probands with the COL5A1 pathogenic variant c.1540G>A, p.(Gly514Ser) who presented with arterial aneurysms, dissections, tortuosity, and mFMD affecting multiple arteries. Arterial medial fibroplasia and smooth muscle cell disorganization were confirmed histologically. The COL5A1 c.1540G>A variant is predicted to be pathogenic in silico and absent in gnomAD. The c.1540G>A variant is on a shared 160.1 kb haplotype with 0.4% frequency in Europeans. Furthermore, exome sequencing data from a cohort of 264 individuals with mFMD were examined for COL5A1 variants. In this mFMD cohort, COL5A1 c.1540G>A and 6 additional relatively rare COL5A1 variants predicted to be deleterious in silico were identified and were associated with arterial dissections (P=0.005).

CONCLUSIONS

COL5A1 c.1540G>A is the first recurring variant recognized to be associated with arterial dissections and mFMD. This variant presents with a phenotype reminiscent of vascular Ehlers-Danlos syndrome. A shared haplotype among probands supports the existence of a common founder. Relatively rare COL5A1 genetic variants predicted to be deleterious by in silico analysis were identified in ≈2.7% of mFMD cases, and as they were enriched in patients with arterial dissections, may act as disease modifiers. Molecular testing for COL5A1 should be considered in patients with a phenotype overlapping with vascular Ehlers-Danlos syndrome and mFMD.

Dissection of coronary artery: A clinical overview

Spontaneous coronary artery dissection (SCAD) is a rare but life-threatening disorder. SCAD is gaining importance as an emerging cause of acute coronary syndrome (ACS), especially in otherwise healthy young women. While SCAD and ACS show similarity in presentation, the management of SCAD differs to that of ACS. If not managed properly SCAD can lead to sudden death. This review examines the pathophysiology, clinical presentation, diagnostic algorithms, and the current and future management of SCAD.

Molecular genetics of human hypertension

PURPOSE OF REVIEW

Genetic variance on blood pressure was shown about 100 years ago; a Mendelian inheritance was initially presumed. Platt and Pickering conducted a lively debate, whether blood pressure was inherited in a Mendelian fashion or whether the condition was polygenic. Genetic-hypertension research has appropriately followed both pathways.

RECENT FINDINGS

Genome-wide association studies, Pickering model, have identified more than 500 blood-pressure loci, the targets of which are waiting to be evaluated. Then, come the 'dark-horses' of hypertension, namely 'secondary' causes. These conditions have been remarkably elucidative including pheochromocytoma, primary aldosteronism, Cushing's syndrome, and even renovascular hypertension. All these conditions feature genetic causes. Finally, arrive the Platt followers. A plethora of Mendelian conditions located within the kidney are established. These syndromes involve increased sodium (as chloride) absorption in the distal nephron. Finally, nonsalt-dependent Mendelian forms involving the vascular directly have been described. Mechanistically, Mendelian forms have large effects on blood pressure and offer effective treatment targets.

SUMMARY

Which genetic models will bring us improved therapies? Ongoing studies will answer that question. It behooves the clinician to follow this dynamic area of research.

Chromosome 1q21.2 and additional loci influence risk of spontaneous coronary artery dissection and myocardial infarction

Spontaneous coronary artery dissection (SCAD) is a non-atherosclerotic cause of myocardial infarction (MI), typically in young women. We undertook a genome-wide association study of SCAD (N_cases = 270/N_controls = 5,263) and identified and replicated an association of rs12740679 at chromosome 1q21.2 (P_{discovery+replication} = 2.19 × 10⁻¹², OR = 1.8) influencing ADAMTSL4 expression. Meta-analysis of discovery and replication samples identified associations with P < 5 × 10⁻⁸ at chromosome 6p24.1 in PHACTR1, chromosome 12q13.3 in LRP1, and in females-only, at chromosome 21q22.11 near LINC00310. A polygenic risk score for SCAD was associated with (1) higher risk of SCAD in individuals with fibromuscular dysplasia (P = 0.021, OR = 1.82 [95% CI: 1.09–3.02]) and (2) lower risk of atherosclerotic coronary artery disease and MI in the UK Biobank (P = 1.28 × 10⁻¹⁷, HR = 0.91 [95% CI :0.89–0.93], for MI) and Million Veteran Program (P = 9.33 × 10⁻³⁶, OR = 0.95 [95% CI: 0.94–0.96], for CAD; P = 3.35 × 10⁻⁶, OR = 0.96 [95% CI: 0.95–0.98] for MI). Here we report that SCAD-related MI and atherosclerotic MI exist at opposite ends of a genetic risk spectrum, inciting MI with disparate underlying vascular biology.

Spontaneous coronary artery dissection (SCAD) is a cause of myocardial infarction Here, the authors present a genome-wide association study of SCAD, finding an association at 1q21.2 which potentially affects expression of ADAMTSL4.

Multiple independent mechanisms link gene polymorphisms in the region of ZEB2 with risk of coronary artery disease

BACKGROUND AND AIMS

Coronary artery disease (CAD) arises from the interaction of genetic and environmental factors. Although genome-wide association studies (GWAS) have identified multiple risk loci and single nucleotide polymorphisms (SNPs) associated with risk of CAD, they are predominantly located in non-coding or intergenic regions and their mechanisms of effect are largely unknown. Accordingly, our objective was to develop a data-driven informatics pipeline to understand complex CAD risk loci, and to apply this to a poorly understood cluster of SNPs in the vicinity of ZEB2.

METHODS

We developed a unique informatics pipeline leveraging a multi-tissue CAD genetics-of-gene-expression dataset, GWAS datasets, and other resources. The pipeline first dissected SNP locations and their linkage disequilibrium relationships, and progressed through analyses of tissue-specific expression quantitative trait loci, and then gene-gene, gene-phenotype, SNP-phenotype relationships. The pipeline concluded by exploring CAD-relevant gene regulatory networks (GRNs).

RESULTS

We identified three independent CAD risk SNPs in close proximity to the ZEB2 coding region (rs6740731, rs17678683 and rs2252641/rs1830321). Our pipeline determined that these SNPs likely act in concert via the atherosclerotic arterial wall and adipose tissues, by governing metabolic and lipid functions. In addition, ZEB2 is the top key driver of a liver-specific GRN that is related to lipid levels, metabolic and anthropometric measures, and CAD severity.

CONCLUSIONS

Using a novel informatics pipeline, we disclosed the multi-faceted mechanisms of action of the ZEB2-associated CAD risk SNPs. This pipeline can serve as a roadmap to dissect complex SNP-gene-tissue-phenotype relationships and to reveal targets for tissue- and gene-specific therapeutic interventions.

Diagnostic approach and management of genetic aortopathies

Aortic aneurysms were the primary cause of nearly 10,000 deaths in 2014 according to data from the Centers for Disease Control and may involve segments of the thoracic or abdominal aorta. Thoracic aortic aneurysms and dissections are more commonly associated with an underlying genetic etiology. In the past several decades, in parallel with the burst of new genome sequencing technologies, a number of genetic aortopathies have been identified. These have provided important insights into the molecular mechanisms of aneurysmal disease, but pose challenges in clinical practice as there are limited consensus recommendations at this time. In this review, we aim to address the pathophysiology, clinical presentation, and treatment considerations in the key heritable thoracic aortopathies.

Identification of Susceptibility Loci for Spontaneous Coronary Artery Dissection

Importance

Spontaneous coronary artery dissection (SCAD), an idiopathic disorder that predominantly affects young to middle-aged women, has emerged as an important cause of acute coronary syndrome, myocardial infarction, and sudden cardiac death.

Objective

To identify common single-nucleotide variants (SNVs) associated with SCAD susceptibility.

Design, Setting, and Participants

This single-center genome-wide association study examined approximately 5 million genotyped and imputed SNVs and subsequent SNV-targeted replication analysis results in individuals enrolled in the Mayo Clinic SCAD registry from August 30, 2011, to August 2, 2018. Data analysis was performed from June 21, 2017, to December 30, 2019.

Main Outcomes and Measures

Genetic loci and positional candidate genes associated with SCAD.

Results

This study included 484 white women with SCAD (mean [SD] age, 46.6 [9.2] years) and 1477 white female controls in the discovery cohort (mean [SD] age, 64.0 [14.5] years) and 183 white women with SCAD (mean [SD] age, 47.1 [9.9] years) and 340 white female controls in the replication cohort (mean [SD] age, 51.0 [15.3] years). Associations with SCAD risk reached genome-wide significance at 3 loci (1q21.3 [OR, 1.78; 95% CI, 1.51-2.09; P = 2.63 × 10-12], 6p24.1 [OR, 1.77; 95% CI, 1.51-2.09; P = 7.09 × 10-12], and 12q13.3 [OR, 1.67; 95% CI, 1.42-1.97; P = 3.62 × 10-10]), and 7 loci had evidence suggestive of an association (1q24.2 [OR, 2.10; 95% CI, 1.58-2.79; P = 2.88 × 10-7], 3q22.3 [OR, 1.47; 95% CI, 1.26-1.71; P = 6.65 × 10-7], 4q34.3 [OR, 1.84; 95% CI, 1.44-2.35; P = 9.80 × 10-7], 8q24.3 [OR, 2.57; 95% CI, 1.76-3.75; P = 9.65 × 10-7], 15q21.1 [OR, 1.75; 95% CI, 1.40-2.18; P = 7.23 × 10-7], 16q24.1 [OR, 1.91; 95% CI, 1.49-2.44; P = 2.56 × 10-7], and 21q22.11 [OR, 2.11; 95% CI, 1.59-2.82; P = 3.12 × 10-7]) after adjusting for the top 5 principal components. Associations were validated for 5 of the 10 risk alleles in the replication cohort. In a meta-analysis of the discovery and replication cohorts, associations for the 5 SNVs were significant, with relatively large effect sizes (1q21.3 [OR, 1.77; 95% CI, 1.54-2.03; P = 3.26 × 10-16], 6p24.1 [OR, 1.71; 95% CI, 1.49-1.97; P = 4.59 × 10-14], 12q13.3 [OR, 1.69; 95% CI, 1.47-1.94; P = 1.42 × 10-13], 15q21.1 [OR, 1.79; 95% CI, 1.48-2.17; P = 2.12 × 10-9], and 21q22.11 [OR, 2.18; 95% CI, 1.70-2.81; P = 1.09 × 10-9]). Each index SNV was within or near a gene highly expressed in arterial tissue and previously linked to SCAD (PHACTR1) and/or other vascular disorders (LRP1, LINC00310, and FBN1).

Conclusions and Relevance

This study revealed 5 replicated risk loci and positional candidate genes for SCAD, most of which are associated with extracoronary arteriopathies. Moreover, the alternate alleles of 3 SNVs have been previously associated with atherosclerotic coronary artery disease, further implicating allelic susceptibility to coronary artery atherosclerosis vs dissection.

Spontaneous Coronary Artery Dissection and Fibromuscular Dysplasia: Vasculopathies With a Predilection for Women

The burden of cardiovascular disease in women is being increasingly appreciated. Nevertheless, both clinicians and the general public are largely unaware that cardiovascular disease is the leading cause of death worldwide in women in all countries and that outcomes after a heart attack are worse for women than men. Of note, certain types of cardiovascular disease have a predilection for women, including spontaneous coronary artery dissection (SCAD) and fibromuscular dysplasia (FMD). Although uncommon, SCAD is being increasingly recognised as the cause of an acute coronary syndrome (ACS) and can recur. It is a potentially fatal, under-diagnosed condition that affects relatively young women, who often have few traditional risk factors, and is the commonest cause of a myocardial infarction associated with pregnancy. In contrast, FMD often remains silent but when manifested can also cause major sequelae, including renal infarction, stroke, cervical artery dissection and gut infarction. Here we provide an update on the diagnosis, aetiology and management of these important disorders that overwhelmingly affect women.

Rare loss-of-function mutations of PTGIR are enriched in fibromuscular dysplasia

Aims

Fibromuscular dysplasia (FMD) and spontaneous coronary artery dissection (SCAD) are related, non-atherosclerotic arterial diseases mainly affecting middle-aged women. Little is known about their physiopathological mechanisms. We aimed to identify rare genetic causes to elucidate molecular mechanisms implicated in FMD and SCAD.

Methods and results

We analysed 29 exomes that included familial and sporadic FMD. We identified one rare loss-of-function variant (LoF) (frequency_gnomAD = 0.000075) shared by two FMD sisters in the prostaglandin I₂ receptor gene (PTGIR), a key player in vascular remodelling. Follow-up was conducted by targeted or Sanger sequencing (1071 FMD and 363 SCAD patients) or lookups in exome (264 FMD) or genome sequences (480 SCAD), all independent and unrelated. It revealed four additional LoF allele carriers, in addition to several rare missense variants, among FMD patients, and two LoF allele carriers among SCAD patients, including one carrying a rare splicing mutation (c.768 + 1C>G). We used burden test to test for enrichment in patients compared to gnomAD controls, which detected a putative enrichment in FMD (P_TRAPD = 8 × 10⁻⁴), but not a significant enrichment (P_TRAPD = 0.12) in SCAD. The biological effects of variants on human prostaclycin receptor (hIP) signalling and protein expression were characterized using transient overexpression in human cells. We confirmed the LoFs (Q163X and P17RfsX6) and one missense (L67P), identified in one FMD and one SCAD patient, to severely impair hIP function in vitro.

Conclusions

Our study shows that rare genetic mutations in PTGIR are enriched among FMD patients and found in SCAD patients, suggesting a role for prostacyclin signalling in non-atherosclerotic stenosis and dissection.

First international consensus on the diagnosis and management of fibromuscular dysplasia

This article is a comprehensive document on the diagnosis and management of fibromuscular dysplasia (FMD) which was commissioned by the Working Group 'Hypertension and the Kidney' of the European Society of Hypertension (ESH) and the Society for Vascular Medicine (SVM). This document updates previous consensus documents/scientific statements on FMD published in 2014 with full harmonization of the position of European and US experts. In addition to practical consensus-based clinical recommendations, including a consensus protocol for catheter-based angiography and percutaneous angioplasty for renal FMD, the document also includes the first analysis of the European/International FMD Registry and provides updated data from the US Registry for FMD. Finally, it provides insights on ongoing research programs and proposes future research directions for understanding this multifaceted arterial disease.

Heart Disease and Stroke Statistics-2020 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports on the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2020 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population, metrics to assess and monitor healthy diets, an enhanced focus on social determinants of health, a focus on the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors, implementation strategies, and implications of the American Heart Association's 2020 Impact Goals.

RESULTS

Each of the 26 chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, healthcare administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

A plasma proteogenomic signature for fibromuscular dysplasia

AIMS

Fibromuscular dysplasia (FMD) is a poorly understood disease that predominantly affects women during middle-life, with features that include stenosis, aneurysm, and dissection of medium-large arteries. Recently, plasma proteomics has emerged as an important means to understand cardiovascular diseases. Our objectives were: (i) to characterize plasma proteins and determine if any exhibit differential abundance in FMD subjects vs. matched healthy controls and (ii) to leverage these protein data to conduct systems analyses to provide biologic insights on FMD, and explore if this could be developed into a blood-based FMD test.

METHODS AND RESULTS

Females with 'multifocal' FMD and matched healthy controls underwent clinical phenotyping, dermal biopsy, and blood draw. Using dual-capture proximity extension assay and nuclear magnetic resonance-spectroscopy, we evaluated plasma levels of 981 proteins and 31 lipid sub-classes, respectively. In a discovery cohort (Ncases = 90, Ncontrols = 100), we identified 105 proteins and 16 lipid sub-classes (predominantly triglycerides and fatty acids) with differential plasma abundance in FMD cases vs. controls. In an independent cohort (Ncases = 23, Ncontrols = 28), we successfully validated 37 plasma proteins and 10 lipid sub-classes with differential abundance. Among these, 5/37 proteins exhibited genetic control and Bayesian analyses identified 3 of these as potential upstream drivers of FMD. In a 3rd cohort (Ncases = 506, Ncontrols = 876) the genetic locus of one of these upstream disease drivers, CD2-associated protein (CD2AP), was independently validated as being associated with risk of having FMD (odds ratios  = 1.36; P = 0.0003). Immune-fluorescence staining identified that CD2AP is expressed by the endothelium of medium-large arteries. Finally, machine learning trained on the discovery cohort was used to develop a test for FMD. When independently applied to the validation cohort, the test showed a c-statistic of 0.73 and sensitivity of 78.3%.

CONCLUSION

FMD exhibits a plasma proteogenomic and lipid signature that includes potential causative disease drivers, and which holds promise for developing a blood-based test for this disease.

Endothelin: 30 Years From Discovery to Therapy

Discovered in 1987 as a potent endothelial cell-derived vasoconstrictor peptide, endothelin-1 (ET-1), the predominant member of the endothelin peptide family, is now recognized as a multifunctional peptide with cytokine-like activity contributing to almost all aspects of physiology and cell function. More than 30 000 scientific articles on endothelin were published over the past 3 decades, leading to the development and subsequent regulatory approval of a new class of therapeutics-the endothelin receptor antagonists (ERAs). This article reviews the history of the discovery of endothelin and its role in genetics, physiology, and disease. Here, we summarize the main clinical trials using ERAs and discuss the role of endothelin in cardiovascular diseases such as arterial hypertension, preecclampsia, coronary atherosclerosis, myocardial infarction in the absence of obstructive coronary artery disease (MINOCA) caused by spontaneous coronary artery dissection (SCAD), Takotsubo syndrome, and heart failure. We also discuss how endothelins contributes to diabetic kidney disease and focal segmental glomerulosclerosis, pulmonary arterial hypertension, as well as cancer, immune disorders, and allograft rejection (which all involve ET_A autoantibodies), and neurological diseases. The application of ERAs, dual endothelin receptor/angiotensin receptor antagonists (DARAs), selective ET_B agonists, novel biologics such as receptor-targeting antibodies, or immunization against ET_A receptors holds the potential to slow the progression or even reverse chronic noncommunicable diseases. Future clinical studies will show whether targeting endothelin receptors can prevent or reduce disability from disease and improve clinical outcome, quality of life, and survival in patients.

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 and Clinical Factors of Migraine in Patients With Spontaneous Coronary Artery Dissection

Background Spontaneous coronary artery dissection (SCAD) is a cause of acute coronary syndrome predominantly in women without usual cardiovascular risk factors. Many have a history of migraine headaches, but this association is poorly understood. This study aimed to determine migraine prevalence among SCAD patients and assess differences in clinical factors based on migraine history. Methods and Results A cohort study was conducted using the Mayo Clinic SCAD "Virtual" Multi-Center Registry composed of patients with SCAD as confirmed on coronary angiography. Participant-provided data and records were reviewed for migraine history, risk factors, SCAD details, therapies, and outcomes. Among 585 patients (96% women), 236 had migraine history; the lifetime and 1-year prevalence of migraine were 40% and 26%, respectively. Migraine was more common in SCAD women than comparable literature-reported female populations (42% versus 24%, P<0.0001; 42% versus 33%, P<0.0001). Among all SCAD patients, those with migraine history were more likely to be female (99.6% versus 94%; P=0.0002); have SCAD at a younger age (45.2±9.0 years versus 47.6±9.9 years; P=0.0027); have depression (27% versus 17%; P=0.025); have recurrent post-SCAD chest pain at 1 month (50% versus 39%; P=0.035); and, among those assessed, have aneurysms, pseudoaneurysms, or dissections (28% versus 18%; P=0.018). There was no difference in recurrent SCAD at 5 years for those with versus without migraine (15% versus 19%; P=0.39). Conclusions Many SCAD patients have a history of migraine. SCAD patients with migraine are younger at the time of SCAD; have more aneurysms, pseudoaneurysms, and dissections among those imaged; and more often report a history of depression and post-SCAD chest pain. Clinical Trial Registration URL: https://www.clinicaltrials.gov . Unique identifiers: NCT01429727, NCT01427179.

Association of the PHACTR1/EDN1 Genetic Locus With Spontaneous Coronary Artery Dissection

BACKGROUND

Spontaneous coronary artery dissection (SCAD) is an increasingly recognized cause of acute coronary syndromes (ACS) afflicting predominantly younger to middle-aged women. Observational studies have reported a high prevalence of extracoronary vascular anomalies, especially fibromuscular dysplasia (FMD) and a low prevalence of coincidental cases of atherosclerosis. PHACTR1/EDN1 is a genetic risk locus for several vascular diseases, including FMD and coronary artery disease, with the putative causal noncoding variant at the rs9349379 locus acting as a potential enhancer for the endothelin-1 (EDN1) gene.

OBJECTIVES

This study sought to test the association between the rs9349379 genotype and SCAD.

METHODS

Results from case control studies from France, United Kingdom, United States, and Australia were analyzed to test the association with SCAD risk, including age at first event, pregnancy-associated SCAD (P-SCAD), and recurrent SCAD.

RESULTS

The previously reported risk allele for FMD (rs9349379-A) was associated with a higher risk of SCAD in all studies. In a meta-analysis of 1,055 SCAD patients and 7,190 controls, the odds ratio (OR) was 1.67 (95% confidence interval [CI]: 1.50 to 1.86) per copy of rs9349379-A. In a subset of 491 SCAD patients, the OR estimate was found to be higher for the association with SCAD in patients without FMD (OR: 1.89; 95% CI: 1.53 to 2.33) than in SCAD cases with FMD (OR: 1.60; 95% CI: 1.28 to 1.99). There was no effect of genotype on age at first event, P-SCAD, or recurrence.

CONCLUSIONS

The first genetic risk factor for SCAD was identified in the largest study conducted to date for this condition. This genetic link may contribute to the clinical overlap between SCAD and FMD.

Migraine headache: Is it only a neurological disorder? Links between migraine and cardiovascular disorders

Migraine headache (MH) is a common disorder affecting millions of people in the United States. MH is substantially more prevalent in women compared to men. An association between migraine with or without aura and risk of cardiovascular disease (CVD) has been extensively reported. There are several proposed theories that may explain the pathophysiologic relationship between MH and CVD. This review will summarize the recent literature on this topic and provide an evidence-based perspective regarding the current knowledge and controversies regarding association of MH and CVD.

Internal carotid and vertebral artery dissection: morphology, pathophysiology and provoking factors

The causes of internal carotid artery (ICA) and vertebral artery (VA) dissection, as well as its provoking factors, remain understudied. The aim of this paper was to explore morphological changes in the ICA/VA walls, factors provoking dissection, clinical signs and biomarkers of connective tissue (CT) damage. A total of 271 patients were examined, of whom 54% were women. The mean age of the participants was 37.0 ± 10 years. Clinical signs and biomarkers of CT damage (matrix metalloproteinase 9, tissue inhibitor of metalloproteinase 1, hydroxyproline, sulphated glycosaminoglycans) were analyzed in 82 patients and 40 healthy volunteers. Histologic examination of dissected and seemingly intact arteries conducted in 5 cases revealed signs of arterial wall dysplasia similar to those characteristics of fibromuscular dysplasia: thinning and splitting of the internal elastic membrane, areas of fibrosis, irregular orientation of myocytes, and their necrosis in the tunica media. Clinical signs and biomarkers of CT dysplasia (CTD) were more pronounced in patients with arterial dissection than in the controls. The major provoking factors were head turns and physical activity (42%), minor head injury (10%), and acute respiratory infection in the month preceding arterial dissection (14%). We conclude that arterial wall dysplasia is a predisposing factor for ICA/VA dissection, both spontaneous and provoked. The analysis of CTD biomarkers and clinical signs suggests connective tissue pathology in patients with ICA/VA dissection.

Subclinical involvement of common carotid arteries in patients with fibromuscular dysplasia - a case-control study

Background: Fibromuscular dysplasia (FMD) primarily involves medium-sized arteries, though the entire spectrum of vascular involvement is not fully understood. We hypothesized that larger arteries may also be affected, albeit sub-clinically. Patients and methods: We measured the cross-sectional diameter of the thoracic aorta, abdominal aorta, common iliac arteries (CIA) and common carotid arteries (CCA) in FMD subjects and compared them to matched controls. We retrospectively analyzed records of FMD subjects (n = 74) and of age- and sex- matched controls (n = 74) that underwent computed tomography of the neck, chest or abdomen. Cross-sectional diameters of the thoracic and abdominal aorta, CIA and CCA were measured in a standardized manner by two trained physicians. Results: The FMD group had a significantly greater diameter of the CIA and CCA bilaterally. The measurements (mm) in FMD and control groups were as follows: Right CIA: 10.85 + 1.75 vs. 10.23 + 1.36, p = 0.04, left CIA: 11.01 + 1.93 vs. 10.15 + 1.38, p = 0.007, right CCA: 7.70 + 0.81 vs. 6.80 + 1.10, p < 0.001 and left CCA: 7.70 + 1.10 vs. 6.80 + 1.0, p < 0.001). There was no difference in the diameter between the two groups in the ascending aorta, descending and the abdominal aorta. After adjusting for baseline differences, common carotid arteries (but not common iliac) were significantly larger in FMD group compared with controls. Conclusions: There is sub-clinical involvement of the common carotid arteries in patients with FMD and this manifests as a greater diameter of these arteries compared to age and sex matched controls.

A Rare Case of 7 Simultaneous Arterial Dissections and Review of The Literature

Objective:

Spontaneous multiple artery dissection is a relatively rare phenomenon. Early clinical signs are often nonspecific, making it difficult to diagnose.

Case Report:

This is a case of a 51-year-old female who presented with spontaneous dissection of 4 visceral arteries, both iliac arteries, and of the right internal carotid artery. The patient underwent urgent successful endovascular repair. Later complications included acute respiratory distress syndrome and pneumonia after massive blood transfusion. She recovered gradually and was discharged after 21 days. Due to this rare presentation, genetic investigation was performed in search of a connective tissue disorder. Results revealed a new COL3A1 subtype mutation. The pathogenicity of this variant remains unclear.

Conclusion:

We recommend a high index of suspicion for visceral artery dissection in the differential diagnosis for abdominal pain with concurrent uncontrolled hypertension. Early diagnosis and intervention are crucial to reducing the mortality rate.

Modern Concepts of Fibromuscular Dysplasia of the Coronary Arteries

Fibromuscular dysplasia of the coronary arteries is a rare non-atherosclerotic and non-inflammatory vascular lesion that is asymptomatic until serious complications develop: stenosis, dissection, rupture, sudden cardiac death. Since there are no long-term numerous clinical observations of patients with fibromuscular dysplasia of the coronary arteries, recommendations have not been developed for diagnosing and treating the disease, which often manifests with acute coronary syndrome. In 2014, the European Consensus was published, and in 2019, the first international consensus document on the diagnosis and treatment of fibromuscular dysplasia with lesions of vessels from different regions (renal, cerebrovascular, coronary, and others). The documents state that the development of fibromuscular dysplasia of the coronary arteries considers the participation of the PHACTR1 gene mutation and the transcriptional activity of the EDN1 gene, smoking, prolonged exertion of the vascular wall, and possibly female sex hormones. In the case of acute coronary syndrome, the most informative diagnostic method is computed tomography with angiography, which reveals a smooth narrowing of the lumen in the middle or distal section in the epicardial artery, often due to intramural hematoma, and also finds dissection, spasm, and tortuous vessel. Additional diagnostic methods ‒ intravascular ultrasound and optical coherence tomography allow differentiation of fibromuscular dysplasia with atherosclerosis of the coronary artery, vasculitis, and other diseases. The choice of treatment tactics for fibromuscular dysplasia of the coronary arteries depends on the severity of the clinical manifestations ‒ conservative medical treatment and interventional methods are used.

Spontaneous coronary artery dissection: etiology and recurrence

Introduction: Spontaneous coronary artery dissection (SCAD) is an increasingly appreciated cause of acute myocardial infarction (AMI) and sudden cardiac death most often affecting young to middle-aged women with few conventional cardiovascular risk factors. Areas covered: A literature search was performed using MedLine, PubMed, and Google Scholar (dating to 04/30/2019). Authors review the key clinical features of SCAD and highlight what is known regarding its pathophysiology and associated factors. The relationship between SCAD and other systemic vasculopathies, notably fibromuscular dysplasia (FMD) is also discussed. Authors also mention the management of acute SCAD along with considerations for long term follow-up such as chest pain syndrome, extracoronary vasculopathy screening, and recurrent SCAD. Expert opinion: Our understanding regarding the association of SCAD and other arteriopathies such as FMD is anticipated to grow. In addition, progress is likely to be made in our efforts to predict recurrent SCAD risk and define potential preventative strategies, possibly through the incorporation of adjunctive imaging.

Prospective Cardiovascular Genetics Evaluation in Spontaneous Coronary Artery Dissection

BACKGROUND

Previous studies describing genetics evaluation in spontaneous coronary artery dissection (SCAD) have been retrospective in nature or presented as single case reports. As part of a dedicated clinical program, we evaluated patients in cardiovascular genetics clinic to determine the role of genetically triggered vascular disease and genetic testing in SCAD.

METHODS AND RESULTS

Patient data were entered prospectively into the Massachusetts General Hospital SCAD registry database from July 2013 to September 2017. Clinically indicated genetic testing was conducted based on patient imaging, family history, physical examination, and patient preference. Of the 107 patients enrolled in the registry, 73 underwent cardiovascular genetics evaluation at our center (average age, 45.3±9.4 years; 85.3% female), and genetic testing was performed for 44 patients. A family history of aneurysm or dissection was not a prevalent feature in the study population, and only 1 patient had a family history of SCAD. Six patients (8.2%) had identifiable genetically triggered vascular disease: 3 with vascular Ehlers-Danlos syndrome (COL3A1), 1 with Nail-patella syndrome (LMX1B), 1 with autosomal dominant polycystic kidney disease (PKD1), and 1 with Loeys-Dietz syndrome (SMAD3). None of these 6 had radiographic evidence of fibromuscular dysplasia.

CONCLUSIONS

In this series, 8.2% of the SCAD patients evaluated had a molecularly identifiable disorder associated with vascular disease. The most common diagnosis was vascular Ehlers-Danlos syndrome. Patients with positive gene testing were significantly younger at the time of their first SCAD event. A low threshold for genetic testing should be considered in patients with SCAD.

Current state-of-play in spontaneous coronary artery dissection

For over 80 years, spontaneous coronary artery dissection (SCAD) has been recognised as a cause of myocardial infarction. SCAD is described as a non-iatrogenic, non-atherosclerotic coronary artery dissection, resulting in formation of a false lumen or intramural haematoma in the coronary artery wall that compresses the true lumen, often compromising myocardial blood flow. In early literature, the incidence of SCAD in acute coronary syndrome (ACS) was underestimated. Recent advances in awareness and widespread early angiographic investigation in ACS has led to important shifts in our understanding of the prevalence, predisposing causes, natural history, aetiology, clinical and angiographic features, management, and prognosis of SCAD. It is now well understood that SCAD predominantly affects women and is responsible for around 20% of ACS presentations in females below the age of 60. Despite this, SCAD is still often overlooked and misdiagnosed as atherosclerotic disease. Misdiagnosis is multifactorial; with contributing factors including a low clinical index of suspicion, particularly in young females, a lack of clinician familiarity with angiographic variants, and limitations of angiography. Although increasing evidence suggests that optimal management is distinct from atherosclerotic coronary artery disease, many questions remain unanswered regarding the pathogenesis and optimal treatment of SCAD, heralding prospective research to answer these questions. This review aims to give a current clinical perspective on SCAD and highlight the importance of familiarity and vigilance with this condition when diagnosing and treating ACS.

Epidemiology, aetiology, and management of ischaemic stroke in young adults

Epidemiological evidence suggests that the incidence of ischaemic stroke in young adults (18-50 years) has increased substantially. These patients have a long life expectancy after stroke, and the costs of long-term care pose huge challenges to health-care systems. Although the current recommendations for treatment of young and old (>50 years) patients with stroke are similar, the optimal management of young adult patients with stroke is unknown. They are usually not included in trials, and specific subanalyses limited to young adult patients with stroke are usually not done, owing to lower incidence of stroke and lower prevalence of vascular risk factors in young adults. Progress has been made in identifying patients with a considerable risk of stroke occurrence, such as those with patent foramen ovale. Future prevention studies might result in a decrease in the incidence of stroke and its sequelae in young adults. The development of guidelines specifically devoted to the management of stroke in young adults will be an important step in achieving this aim.

Neuroimaging of Pediatric Arteriopathies

Pediatric arteriopathies are increasingly recognized in school-aged children with a variety of presenting symptoms ranging from headache, seizures, encephalopathy, and neuropsychiatric symptoms as well as focal neurologic deficits due to acute ischemic strokes. However, unlike the adult stroke population, there are differences in the clinical manifestations, the stroke mechanism, and risk factors in pediatric ischemic stroke. There has been increasing awareness and recognition of pediatric cerebral arteriopathies as a predominant stroke etiology. Prompt diagnosis of arteriopathies is essential to limit injury and prevent recurrent stroke. Based on predominant vessels involved and clinical symptoms, these arteriopathies can be broadly divided into two categories: large-medium size arteriopathies and small vessel arteriopathies. Each category can be further divided into inflammatory and noninflammatory according to their etiologies. The ability to distinguish between inflammatory and noninflammatory etiologies carries major prognostic implications for acute management and secondary stroke prevention as well as screening for systemic complications and counseling.