Genetic Testing in Thoracic Aortic Disease--When, Why, and How?

Advances in genetic technology over the past 10 years have revealed the polygenic basis of thoracic aortic aneurysm and thoracic aortic acute dissection (TAAD) in a subset of patients. There is mounting evidence to show that clinical risk stratification for aneurysmal dilatation and acute dissection can be based on genotype for some of the known genes, allowing individualized medical and surgical management with the aim of reducing morbidity and mortality. This evidence has led to a recommendation by the American College of Cardiology Foundation and the American Heart Association that the underlying genetic mutation should dictate the timing of aortic repair. Other benefits of identifying a specific genetic cause include prediction of multisystem involvement in syndromic forms of TAAD and cascade screening for other at-risk family members. Mutation analysis for genes associated with TAAD in a clinical setting is typically ordered by geneticists or cardiologists with an interest or expertise in cardiac genetics. We present an approach to assist cardiologists and vascular surgeons in recognizing which patients would benefit from genetic testing, provide justification for such testing, and outline a practical approach to ordering the tests.