At the Crossroad of Transforming Growth Factor-β Signaling and Vascular Smooth Muscle Cell Contractility

Aortic aneurysm and dissections account for 1% to 2% of all deaths in the Western countries, and the incidence of thoracic aortic aneurysm (TAA) is ≈10.4 per 100 000 personyears. Furthermore, because acute aortic dissections might be disguised as heart attacks, true incidence numbers could be significantly higher. Aortic aneurysms are categorized into 2 main groups depending on their location: TAAs and abdominal aortic aneurysms. Abdominal aortic aneurysms are the most common group and are linked to various lifestyle-associated risk factors, including hyperlipidemia, hypertension, sex, and age. However, smoking is generally regarded as the most important risk factor. Heritability estimates as high as 70% have been found, and recently, several genes and loci have been associated with abdominal aortic aneurysms (DAB2IP, LRP1, CDKN2B-AS1, CNTN3, LPA, IL6R, and the sortilin-1 [SORT1] locus). In this review, we focus on TAA, which have an even stronger genetic component, with 20% of patients having a positive family history. This number is also likely to be underestimated because developing TAA usually remain asymptomatic. TAA can develop at the ascending Review