Importance: Spontaneous coronary artery dissection (SCAD) is a major cause of acute coronary syndrome in young women, especially among those without traditional cardiovascular risk factors. Prior efforts to study SCAD have been hampered by underrecognition and lack of registry-based studies. Risk factors and pathogenesis remain largely undefined, and inheritability has not been reported.
Observations: Using novel research methods, patient champions, and social media, the Mayo Clinic SCAD Registry has been able to better characterize this condition, which was previously considered rare. Of 412 patient enrollees, we identified 5 familial cases of SCAD comprising affected mother-daughter, identical twin sister, sister, aunt-niece, and first-cousin pairs, implicating both recessive and dominant modes of inheritance. The mother-daughter pair also reported fatal myocardial infarction in 3 maternal relatives. None of the participants had other potential risk factors for SCAD, including connective tissue disorders or peripartum status.
Conclusions and relevance: To our knowledge, this series is the first to identify a familial association in SCAD suggesting a genetic predisposition. Recognition of SCAD as a heritable disorder has implications for at-risk family members and furthers our understanding of the pathogenesis of this complex disease. Whole-exome sequencing provides a unique opportunity to identify the molecular underpinnings of SCAD susceptibility.