Natural history of thoracic aortic aneurysms: size matters, plus moving beyond size.

Thoracic aortic aneurysms (TAAs) are a prevalent and deadly disease that, without diagnosis and treatment, eventuates in life-threatening aortic dissection or rupture. While TAAs normally grow in an indolent manner, once a certain size (a "hinge point") is reached, the risk of dissection, rupture, and death increases dramatically. By virtue of their common clinical "silence," many TAAs are not diagnosed until such complications occur. While size is a helpful criterion for intervention, there is a need for parameters and markers besides aortic aneurysm size for use in diagnosing and monitoring TAAs so as to prevent natural complications of this disease.