Prevalence of Guideline-Recommended Genetic Testing in Patients at Risk for Heritable Thoracic Aortic Disease.

Heritable thoracic aortic diseases (HTAD) include genetic conditions that increase risk of thoracic aortic aneurysm and dissection. The 2022 American College of Cardiology/American Heart Association (ACC/AHA) guidelines recommend genetic testing for at-risk individuals, but real-world uptake remains unclear. We evaluated adherence to testing recommendations and demographic differences across major HTAD risk cohorts. We conducted a retrospective study using the TriNetX Research Network (2005-2025). Three guideline-based cohorts were identified using International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes: (1) thoracic aortic aneurysm/dissection before age 60, (2) family history of thoracic aortic disease, and (3) non-thoracic arterial aneurysms. Genetic testing was defined by ICD-10-CM codes for genetic screening or susceptibility. Testing prevalence was stratified by age, sex, race, and ethnicity, and annual testing incidence (2005-2024) was evaluated. Among 57,935 patients with thoracic aortic aneurysm/dissection before age 60, 1,205 (2.09%) underwent genetic testing. Among 2,811,862 patients with a family history of thoracic aortic disease, 66,699 (2.38%) received testing. Among 347,000 patients with non-thoracic arterial aneurysms, 4,913 (1.42%) underwent testing. Testing was consistently higher in females than males and varied across age groups. Annual testing incidence increased over time but remained <0.6% by 2024. In conclusion, genetic testing for HTAD remains markedly underutilized, with < 2.5% of at-risk patients tested despite guideline recommendations, highlighting persistent implementation gaps and the need to improve equitable access to genetic evaluation.