Burden of Rare Genetic Variants in Spontaneous Coronary Artery Dissection With High-risk Features

Cross-Ancestry Associations of Spontaneous Coronary Artery Dissection Genetic Risk With Coronary Atherosclerosis and Migraine Headache

BACKGROUND

Research studies of spontaneous coronary artery dissection (SCAD) have been primarily focused on European-ancestry individuals, with limited recognition and investigation in non-European-ancestry individuals. While SCAD has not been well ascertained in non-European-ancestry groups, pleiotropic associated traits identified in those of European ancestry have been assessed in individuals of other ancestries. Whether these traits are associated with the complex genetic architecture of SCAD in those of non-European ancestry has not been previously investigated.

METHODS

We investigated the associations of an established SCAD polygenic score with multiple vascular diseases in ≈900 000 ancestrally diverse participants of large-scale studies. Individual-level data from the UK Biobank and the Million Veteran Program and summary statistics of publicly available databases were analyzed.

RESULTS

A set of associations between SCAD polygenic score and related vascular diseases were replicated in non-European samples. Notable associations with the SCAD polygenic score included (1) coronary artery disease, myocardial infarction, and migraine headache in a Hispanic group (coronary artery disease: odds ratio [OR], 0.93 [95% CI, 0.90-0.95]; P=2.35×10-7; myocardial infarction: OR, 0.88 [95% CI, 0.80-0.96]; P=5.73×10-3; migraine headache: OR, 1.03 [95% CI, 1.01-1.06]; P=1.86×10-2) of the Million Veteran Program; (2) headache in an African-ancestry group (OR, 1.22 [95% CI, 1.06-1.41]; P=6.94×10-3) and a South Asian-ancestry group (OR, 1.18 [95% CI, 1.02-1.37]; P=2.43×10-2) of the UK Biobank; and (3) coronary artery disease, myocardial infarction, and migraine headache in East Asian-ancestry cohorts (coronary artery disease: OR, 0.95 [95% CI, 0.93-0.98]; P=2.66×10-3; myocardial infarction: OR, 0.86 [95% CI, 0.83-0.89]; P=9.51×10-16; migraine headache: OR, 1.27 [95% CI, 1.10-1.47]; P=1.03×10-3).

CONCLUSIONS

Pleiotropic associations of SCAD polygenic risk with related vascular diseases previously identified in European-ancestry groups showed notable, largely consistent patterns in non-European-ancestry groups.

Integrative gene regulatory network analysis discloses key driver genes of fibromuscular dysplasia

Fibromuscular dysplasia (FMD) is a poorly understood disease affecting 3-5% of adult females. The pathobiology of FMD involves arterial lesions of stenosis, dissection, tortuosity, dilation and aneurysm, which can lead to hypertension, stroke, myocardial infarction and even death. Currently, there are no animal models for FMD and few insights as to its pathobiology. In this study, by integrating DNA genotype and RNA sequence data from primary fibroblasts of 83 patients with FMD and 71 matched healthy controls, we inferred 18 gene regulatory co-expression networks, four of which were found to act together as an FMD-associated supernetwork in the arterial wall. After in vivo perturbation of this co-expression supernetwork by selective knockout of a top network key driver, mice developed arterial dilation, a hallmark of FMD. Molecular studies indicated that this supernetwork governs multiple aspects of vascular cell physiology and functionality, including collagen/matrix production. These studies illuminate the complex causal mechanisms of FMD and suggest a potential therapeutic avenue for this challenging disease.

The genetics of spontaneous coronary artery dissection: a scoping review

BACKGROUND

Spontaneous coronary artery dissection (SCAD) is a multifactorial process that involves predisposing factors and precipitating stressors. Genetic abnormality has been implicated to play a mechanistic role in the development of SCAD. This systematic review aims to summarize the current evidence concerning the link between SCAD and genetic abnormalities.

METHODS

We reviewed original studies published until May 2023 that reported SCAD patients with a genetic mutation by searching PubMed, Embase Ovid, and Google Scholar. Registries, cohort studies, and case reports were included if a definitive SCAD diagnosis was reported, and the genetic analysis was performed. Exclusion criteria included editorials, reviews, letters or commentaries, animal studies, meeting papers, and studies from which we were unable to extract data. Data were extracted from published reports.

RESULTS

A total of 595 studies were screened and 55 studies were identified. Among 116 SCAD patients with genetic abnormalities, 20% had mutations in the COL gene, 13.70% TLN1 gene, and 8.42% TSR1 gene. Mutations affecting the genes encoding COL and TLN1 were most frequently reported (20 and 13.7%, respectively). Interestingly, 15 genes of this collection were also reported in patients with thoracic aortic diseases as well. The genetic commonality between fibromuscular dysplasia (FMD) and SCAD was also included.

CONCLUSION

In this review, the inherited conditions and reported genes of undetermined significance from case reports associated with SCAD are collected. A brief description of the encoded protein and the clinical features associated with pathologic genes is provided. Current data suggested that the diagnostic yield of genetic studies for patients with SCAD would be low and routine genetic screening of such patients with no clinical features indicative of associated disorders remains debatable. This review can be used as a guide for clinicians to recognize inherited syndromic and nonsyndromic disorders associated with SCAD.

From Atherosclerosis to Spontaneous Coronary Artery Dissection: Defining a Clinical and Genetic Risk Spectrum for Myocardial Infarction

PURPOSE OF REVIEW

Spontaneous coronary artery dissection (SCAD) has been increasingly recognized as a significant cause of acute myocardial infarction (AMI) in young and middle-aged women and arises through mechanisms independent of atherosclerosis. SCAD has a multifactorial etiology that includes environmental, individual, and genetic factors distinct from those typically associated with coronary artery disease. Here, we summarize the current understanding of the genetic factors contributing to the development of SCAD and highlight those factors which differentiate SCAD from atherosclerotic coronary artery disease.

RECENT FINDINGS

Recent studies have revealed several associated variants with varying effect sizes for SCAD, giving rise to a complex genetic architecture. Associated genes highlight an important role for arterial cells and their extracellular matrix in the pathogenesis of SCAD, as well as notable genetic overlap between SCAD and other systemic arteriopathies such as fibromuscular dysplasia and vascular connective tissue diseases. Further investigation of individual variants (including in the associated gene PHACTR1) along with polygenic score analysis have demonstrated an inverse genetic relationship between SCAD and atherosclerosis as distinct causes of AMI. SCAD represents an increasingly recognized cause of AMI with opposing clinical and genetic risk factors from that of AMI due to atherosclerosis, and it is often associated with complex underlying genetic conditions. Genetic study of SCAD on a larger scale and with more diverse cohorts will not only further our evolving understanding of a newly defined genetic spectrum for AMI, but it will also inform the clinical utility of integrating genetic testing in AMI prevention and management moving forward.

Genetic testing in cardiovascular disease

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality globally and is responsible for an estimated one-third of deaths as well as significant morbidity and health care utilisation. Technological and bioinformatic advances have facilitated the discovery of pathogenic germline variants for some specific CVDs, including familial hypercholesterolaemia, cardiomyopathies and arrhythmic syndromes. Use of these genetic tests for earlier disease identification is increasing due, in part, to decreasing costs, Medicare rebates, and consumer comfort with genetic testing. However, CVDs that occur more commonly, including coronary artery disease and atrial fibrillation, do not display monogenic inheritance patterns. Genetically, these diseases have generally been associated with many genetic variants each with a small effect size. This complexity can be expressed mathematically as a polygenic risk score. Genetic testing kits that provide polygenic risk scoring are becoming increasingly available directly to private-paying consumers outside the traditional clinical setting. An improved understanding of the evidence of genetics in CVD will offer clinicians new opportunities for individualised risk prediction and preventive therapy.

Secreted ADAMTS-like proteins as regulators of connective tissue function

The extracellular matrix (ECM) determines functional properties of connective tissues through structural components, such as collagens, elastic fibers, or proteoglycans. The ECM also instructs cell behavior through regulatory proteins, including proteases, growth factors, and matricellular proteins, which can be soluble or tethered to ECM scaffolds. The secreted a disintegrin and metalloproteinase with thrombospondin type 1 repeats/motifs-like (ADAMTSL) proteins constitute a family of regulatory ECM proteins that are related to ADAMTS proteases but lack their protease domains. In mammals, the ADAMTSL protein family comprises seven members, ADAMTSL1-6 and papilin. ADAMTSL orthologs are also present in the worm, Caenorhabditis elegans, and the fruit fly, Drosophila melanogaster. Like other matricellular proteins, ADAMTSL expression is characterized by tight spatiotemporal regulation during embryonic development and early postnatal growth and by cell type- and tissue-specific functional pleiotropy. Although largely quiescent during adult tissue homeostasis, reexpression of ADAMTSL proteins is frequently observed in the context of physiological and pathological tissue remodeling and during regeneration and repair after injury. The diverse functions of ADAMTSL proteins are further evident from disorders caused by mutations in individual ADAMTSL proteins, which can affect multiple organ systems. In addition, genome-wide association studies (GWAS) have linked single nucleotide polymorphisms (SNPs) in ADAMTSL genes to complex traits, such as lung function, asthma, height, body mass, fibrosis, or schizophrenia. In this review, we summarize the current knowledge about individual members of the ADAMTSL protein family and highlight recent mechanistic studies that began to elucidate their diverse functions.

Polygenic Risk in Families With Spontaneous Coronary Artery Dissection

Importance

Spontaneous coronary artery dissection (SCAD) is a poorly understood cause of acute coronary syndrome that predominantly affects women. Evidence to date suggests a complex genetic architecture, while a family history is reported for a minority of cases.

Objective

To determine the contribution of rare and common genetic variants to SCAD risk in familial cases, the latter via the comparison of a polygenic risk score (PRS) with those with sporadic SCAD and healthy controls.

Design, Setting, and Participants

This genetic association study analyzed families with SCAD, individuals with sporadic SCAD, and healthy controls. Genotyping was undertaken for all participants. Participants were recruited between 2017 and 2021. A PRS for SCAD was calculated for all participants. The presence of rare variants in genes associated with connective tissue disorders (CTD) was also assessed. Individuals with SCAD were recruited via social media or from a single medical center. A previously published control database of older healthy individuals was used. Data were analyzed from January 2022 to October 2023.

Exposures

PRS for SCAD comprised of 7 single-nucleotide variants.

Main Outcomes and Measures

Disease status (familial SCAD, sporadic SCAD, or healthy control) associated with PRS.

Results

A total of 13 families with SCAD (27 affected and 12 unaffected individuals), 173 individuals with sporadic SCAD, and 1127 healthy controls were included. A total of 188 individuals with SCAD (94.0%) were female, including 25 of 27 with familial SCAD and 163 of 173 with sporadic SCAD; of 12 unaffected individuals from families with SCAD, 6 (50%) were female; and of 1127 healthy controls, 672 (59.6%) were female. Compared with healthy controls, the odds of being an affected family member or having sporadic SCAD was significantly associated with a SCAD PRS (where the odds ratio [OR] represents an increase in odds per 1-SD increase in PRS) (affected family member: OR, 2.14; 95% CI, 1.78-2.50; adjusted P = 1.96 × 10-4; sporadic SCAD: OR, 1.63; 95% CI, 1.37-1.89; adjusted P = 5.69 × 10-4). This association was not seen for unaffected family members (OR, 1.03; 95% CI, 0.46-1.61; adjusted P = .91) compared with controls. Further, those with familial SCAD were overrepresented in the top quintile of the control PRS distribution (OR, 3.70; 95% CI, 2.93-4.47; adjusted P = .001); those with sporadic SCAD showed a similar pattern (OR, 2.51; 95% CI, 1.98-3.04; adjusted P = .001). Affected individuals within a family did not share any rare deleterious variants in CTD-associated genes.

Conclusions and Relevance

Extreme aggregation of common genetic risk appears to play a significant role in familial clustering of SCAD as well as in sporadic case predisposition, although further study is required.

Emerging roles for the ADAMTS-like family of matricellular proteins in cardiovascular disease through regulation of the extracellular microenvironment

Dysregulation of the extracellular matrix (ECM) occurs widely across cardiovascular pathologies. Recent work has revealed important roles for the «a disintegrin-like and metalloprotease domain with thrombospondin-type 1 motifs like" (ADAMTSL) family of secreted glycoproteins in cardiovascular tissues during development and disease. Key insights in this regard have come from naturally occurring gene mutations in humans and animals that result in severe diseases with cardiovascular manifestations or aortopathies. Expression of ADAMTSL genes is greatly increased in the myocardium during heart failure. Genetically modified mice recapitulate phenotypes of patients with ADAMTSL mutations and demonstrate important functions in the ECM. The novel functions thus disclosed are intriguing because, while these proteins are neither structural, nor proteases like the related ADAMTS proteases, they appear to act as regulatory, i.e., matricellular proteins. Evidence from genetic variants, genetically engineered mouse mutants, and in vitro investigations have revealed regulatory functions of ADAMTSLs related to fibrillin microfibrils and growth factor signaling. Interestingly, the ability to regulate transforming growth factor (TGF)β signaling may be a shared characteristic of some ADAMTSLs. TGFβ signaling is important in cardiovascular development, health and disease and a central driver of ECM remodeling and cardiac fibrosis. New strategies to target dysregulated TGFβ signaling are warranted in aortopathies and cardiac fibrosis. With their emerging roles in cardiovascular tissues, the ADAMTSL proteins may provide causative genes, diagnostic biomarkers and novel treatment targets in cardiovascular disease. Here, we discuss the relevance of ADAMTSLs to cardiovascular medicine.

Spontaneous Coronary Artery Dissection and Fibromuscular Dysplasia: A Case Series and Genetic Links

Spontaneous coronary artery dissection (SCAD) is a rare cause of myocardial infarction in young women. An association of fibromuscular dysplasia (FMD) with SCAD has been well established; a significant proportion of SCAD patients may have typical FMD findings in other noncoronary arteries. The current consensus recommends arterial imaging screening from head to pelvis using computed tomography angiography (CTA) or magnetic resonance angiography (MRA) in SCAD. Genetic testing for FMD should be considered in high-risk cases. We present two cases of SCAD associated with FMD and discuss the significance of genetic screening in such patients.

Gene Commonality in Arterial Circuits Throughout the Body

The common genetic underpinnings of thoracic aortic aneurysms and aneurysms and dissections of several other major arterial circuits have been described in the literature. These include thoracic and abdominal aortic aneurysms, thoracic and intracranial aneurysms, thoracic aortic aneurysms, and spontaneous coronary artery dissections. In this study, we provide a unified report of these observations and investigate any genetic commonality between the above four arterial circulations.

Spontaneous Coronary Artery Dissection in Clinical Practice: Pathophysiology and Therapeutic Approaches

Spontaneous coronary artery dissection (SCAD) is a cause of myocardial infarction without obstructive coronary artery disease (MINOCA). It is determined by a coronary artery wall layers separation, which occurs regardless of traumatic or iatrogenic injuries. Even if it is often a missed diagnosis, its incidence is growing along with the improvement of intracoronary imaging techniques that allow for better detection. The main angiographical classification distinguishes three different forms, with slightly different prognoses at long-term follow up. SCAD is a recurrent condition, severely hampering the life quality of affected patients. The predominantly young age of patients with SCAD and the high prevalence of females among them have made the topic increasingly important, especially regarding therapeutic strategies. According to the data, the most recommended treatment is conservative, based on the use of antiplatelet agents and supportive anti-ischemic therapy. However, there are conflicting opinions concerning the need for dual antiplatelet therapy and its duration. In the case of invasive treatment, the choice between percutaneous coronary intervention and coronary artery bypass graft depends on the patient's clinical stability and the interested vessel. The purpose of the current review is to revise the pathophysiological mechanisms underlying SCAD and the current knowledge of its treatment.

Spontaneous coronary artery dissection: An underrecognized cause of ACS

ABSTRACT

Spontaneous coronary artery dissection (SCAD) is an underrecognized form of nonatherosclerotic acute coronary syndrome, mostly occurring in younger female patients. The knowledge base about the diagnosis and management of SCAD has grown over the past decade, but gaps remain in how best to approach this disease. This article reviews the research on the prevalence, presentation, and management of SCAD.

Advancements in the Genetics of Spontaneous Coronary Artery Dissection

PURPOSE OF REVIEW

Spontaneous coronary artery dissection (SCAD) is a significant cause of acute myocardial infarction that is increasingly recognized in young and middle-aged women. The etiology of SCAD is likely multifactorial and may include the interaction of environmental and individual factors. Here, we summarize the current understanding of the genetic factors contributing to the development of SCAD.

RECENT FINDINGS

The molecular findings underlying SCAD have been demonstrated to include a combination of rare DNA sequence variants with large effects, common variants contributing to a complex genetic architecture, and variants with intermediate impact. The genes associated with SCAD highlight the role of arterial cells and their extracellular matrix in the pathogenesis of the disease and shed light on the relationship between SCAD and other disorders, including fibromuscular dysplasia and connective tissue diseases. While up to 10% of affected individuals may harbor a rare variant with large effect, SCAD most often presents as a complex genetic condition. Analyses of larger and more diverse cohorts will continue to improve our understanding of risk susceptibility loci and will also enable consideration of the clinical utility of genetic testing strategies in the management of SCAD.

Identification of Rare Genetic Variants in Familial Spontaneous Coronary Artery Dissection and Evidence for Shared Biological Pathways

Rare familial spontaneous coronary artery dissection (SCAD) kindreds implicate genetic disease predisposition and provide a unique opportunity for candidate gene discovery. Whole-genome sequencing was performed in fifteen probands with non-syndromic SCAD who had a relative with SCAD, eight of whom had a second relative with extra-coronary arteriopathy. Co-segregating variants and associated genes were prioritized by quantitative variant, gene, and disease-level metrics. Curated public databases were queried for functional relationships among encoded proteins. Fifty-four heterozygous coding variants in thirteen families co-segregated with disease and fulfilled primary filters of rarity, gene variation constraint, and predicted-deleterious protein effect. Secondary filters yielded 11 prioritized candidate genes in 12 families, with high arterial tissue expression (n = 7), high-confidence protein-level interactions with genes associated with SCAD previously (n = 10), and/or previous associations with connective tissue disorders and aortopathies (n = 3) or other vascular phenotypes in mice or humans (n = 11). High-confidence associations were identified among 10 familial SCAD candidate-gene-encoded proteins. A collagen-encoding gene was identified in five families, two with distinct variants in COL4A2. Familial SCAD is genetically heterogeneous, yet perturbations of extracellular matrix, cytoskeletal, and cell-cell adhesion proteins implicate common disease-susceptibility pathways. Incomplete penetrance and variable expression suggest genetic or environmental modifiers.

Precipitating factors in patients with spontaneous coronary artery dissection: Clinical, laboratoristic and prognostic implications

BACKGROUND

Spontaneous coronary artery dissection (SCAD) often presents with acute coronary syndrome and underlying pathophysiology involves the interplay between predisposing factors and precipitating stressors, such as emotional and physical triggers. In our study we sought to compare clinical, angiographic and prognostic features in a cohort of patients with SCAD according to the presence and type of precipitating stressors.

METHODS

Consecutive patients with angiographic evidence of SCAD were divided into three groups: patients with emotional stressors, patients with physical stressors and those without any stressor. Clinical, laboratoristic and angiographic features were collected for each patient. The incidence of major adverse cardiovascular events, recurrent SCAD and recurrent angina was assessed at follow-up.

RESULTS

Among the total population (64 subjects), 41 [64.0%] patients presented with precipitating stressors, including emotional triggers (31 [48.4%] subjects) and physical efforts (10 [15.6%] subjects). As compared with the other groups, patients with emotional triggers were more frequently female (p = 0.009), had a lower prevalence of hypertension (p = 0.039] and dyslipidemia (p = 0.039), were more likely to suffer from chronic stress (p = 0.022) and presented with higher levels of C-reactive protein (p = 0.037) and circulating eosinophils cells (p = 0.012). At a median follow-up of 21 [7; 44] months, patients with emotional stressors experienced higher prevalence of recurrent angina (p = 0.025), as compared to the other groups.

CONCLUSIONS

Our study shows that emotional stressors leading to SCAD may identify a SCAD subtype with specific features and a trend towards a worse clinical outcome.