Genetic Overlap of Spontaneous Dissection of Either the Thoracic Aorta or the Coronary Arteries

Spontaneous Coronary Artery Dissection and a Family History of Aortic Dissection: A Genetic Association Study

BACKGROUND

Spontaneous coronary artery dissection (SCAD) is an increasingly recognized cause of acute coronary syndrome or sudden cardiac death, primarily affecting relatively young women (median age, 51 years) without typical cardiovascular risk factors. SCAD has a genetic component, with genome-wide association studies identifying multiple risk loci. Thoracic aortic dissection (type A) shares some genetic overlap with SCAD, suggesting potential common predispositions.

METHODS

We performed genetic screening or whole-genome sequencing of 17 patients with SCAD (94% women) with a first- or second-degree relative (89% men) affected by aortic dissection (AD). We assessed rare variants in candidate genes and genome-wide using the American College of Medical Genetics and Genomics criteria. Polygenic risk scores were calculated to assess genetic risk for SCAD, fibromuscular dysplasia, AD, and abdominal aortic aneurysm in patients with SCAD, relatives with AD, and controls.

RESULTS

Whole-genome sequencing identified pathogenic or likely pathogenic variants in SMAD3, CBS, and COL3A1 in 3 SCAD cases. Additionally, 4 variants of uncertain significance were found in candidate genes. Polygenic risk scores for SCAD were significantly associated with increased odds of SCAD in probands versus controls (odds ratio, 1.79 [95% CI, 1.08-2.99]; P=0.024).

CONCLUSIONS

Our study supports a complex genetic landscape underlying SCAD, implicating rare monogenic pathogenic variants and polygenic risk. We identified pathogenic variants in patients with SCAD with a family history of AD, highlighting potential genetic links between these vascular disorders. The findings underscore the importance of genetic screening in patients with SCAD with a history of AD to identify individuals at risk and guide preventive strategies.

Genetic Overlap of Thoracic Aortic Aneurysms and Intracranial Aneurysms

OBJECTIVE

Thoracic aortic aneurysms (TAAs) and intracranial aneurysms (ICAs) share overlapping genetic and pathophysiological mechanisms, yet the genetic interplay between these conditions remains insufficiently explored. This study aimed to identify common genetic factors underlying TAA and ICA.

METHODS

A comprehensive review of genome-wide association studies (GWASs) and retrospective clinical studies was conducted using PubMed, Orbis, and Web of Science. Articles addressing the genetic etiologies of TAA and ICA were analyzed. Separate lists of causative genes were compiled, and commonalities were identified. A Venn diagram was constructed to illustrate genetic overlap and shared physiological pathways.

RESULTS

We identified 24 overlapping genes associated with TAA and ICA, including LTBP2, TGFB2, TGFB3, TGFBR1, TGFBR2, SMAD2, SMAD3, COL1A2, COL3A1, COL4A1, COL5A1, COL5A2, FBN1, FBN2, ELN, LOX ACTA2, MYH11, MYLK, ABCC6, NOTCH1, MED12, PKD1, and PKD2. These genes are involved in pathways related to connective tissue biology, contractile elements, extracellular matrix components, and transforming growth factor-β signaling. While vascular endothelium and cell cycle pathways were unique to ICA, TAA pathways predominantly involved extracellular matrix remodeling.

CONCLUSIONS

This study highlights the significant genetic overlap between TAA and ICA, shedding light on shared molecular mechanisms. These findings underscore the importance of interdisciplinary awareness: neurologists, neurosurgeons, and neurointerventional radiologists should monitor ICA patients for potential TAA, while cardiologists, cardiac surgeons, vascular surgeons, and vascular interventionalists should consider ICA risks in TAA patients. Further research into these genetic pathways could enhance the understanding and management of both conditions.

Long-term outcomes in thoracic aortic surgery: 11 year single centre experience

OBJECTIVES

Thoracic aortic aneurysms and dissections provide a complex surgical cohort termed thoracic aortic surgery. Regular follow-up at specialist clinics with cross-sectional imaging is recommended. Identifying risk factors that lead to re-operations as well as the requirement for and appropriate length of follow-up remain points of debate.

METHODS

Patients undergoing thoracic aortic surgery performed at a single centre from January 2012 to December 2022 were retrospectively reviewed. The clinical information, operative details, histological reports, post-operative outcomes and follow up were collected from electronic patient records. Statistical analysis was performed using Microsoft Excel and R Studio.

RESULTS

409 patients met the inclusion criteria for the study with a median follow-up of 3.8 years (IQR 1.6-7.6). The prevalence of all cause re-operations was 10.8% (n = 44). The median time to re-operation was 1.8 years. 68% of the reoperations occurred within the first 5 years. Multi and univariate logistic regression identified young age, arteritis and/or aortitis as the main risk factors associated with increased risk of re-operation. Connective tissue disease and systemic inflammatory diseases approached but didn't meet statistical significance. Bicuspid aortic valve pathology was associated with reduced risk of re-operation.

CONCLUSIONS

Patients undergoing thoracic aortic surgery have a high rate of re-operation. The first 5 years represent a high-risk period and follow-up with cross-sectional imaging during that time by specialist aortic services is essential. Patient with aortitis remain at high risk and should be treated by appropriate by specialist aortic services with subspecialty interest and expertise on treating patients with aortitis.

Genetics architecture of spontaneous coronary artery dissection in an Italian cohort

Spontaneous coronary artery dissection (SCAD) is a relevant non-atherosclerotic cause of acute coronary syndrome with a complex genetic architecture. Recent discoveries have highlighted the potential role of miRNAs and protein-coding genes involved in the processing of small RNAs in the pathogenesis of SCAD. Furthermore, there may be a connection between SCAD and the increased cardiovascular risk observed in fragile X premutation carriers as well as a correlation with pathogenetic variants in genes encoding for collagen and extracellular matrix, which are related to connective tissue disorders (CTDs). In our cohort of 15 Italian SCAD patients, a total of 37 rare variants were identified in 34 genes using whole exome sequencing (WES) and TRIO-WES analysis when both parents were available. Three likely pathogenic/pathogenetic variants were found in genes previously associated with SCAD and CTDs (COL3A1, COL1A2, and SMAD3) and 26 variants of uncertain significance in genes previously associated with SCAD and CTDs. TRIO-WES analysis revealed 7 de novo variants, 1 of which was found in a potential novel candidate gene (DROSHA). In addition, a premutation allele of 55 ± 2 CGG repeats in the promoter of the FMR1 gene was identified in two related SCAD patients by test for CGG-repeat expansions in the 5'-UTR of the FMR1 gene. Our findings suggest various potential mechanisms such as mRNA toxicity, miRNA regulation, alteration of collagen, and the extracellular matrix architecture, all of which could disrupt vascular homeostasis, and finally, WES and TRIO-WES have proven to be the most powerful approaches for characterizing the genetic background of SCAD.

Heritable thoracic aortic disease: a literature review on genetic aortopathies and current surgical management

Heritable thoracic aortic disease puts patients at risk for aortic aneurysms, rupture, and dissections. The diagnosis and management of this heterogenous patient population continues to evolve. Last year, the American Heart Association/American College of Cardiology Joint Committee published diagnosis and management guidelines for aortic disease, which included those with genetic aortopathies. Additionally, evolving research studying the implications of underlying genetic aberrations with new genetic testing continues to become available. In this review, we evaluate the current literature surrounding the diagnosis and management of heritable thoracic aortic disease, as well as novel therapeutic approaches and future directions of research.

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.