Thoracic Aortic Aneurysm

An arterial aneurysm is a localized pathological dilation of the artery with a diameter of 1.5 times that of the normal artery . The histopathology of some aortic aneurysms includes medial degeneration with elastic fiber loss from the medial layer, loss of vascular smooth muscle cells, and proteoglycan deposition. Dissection of the thoracic aorta involves disruption of the medial layer with intramural hemorrhage causing propagation and tracking of blood within the media.

The DeBakey classification system states that a type I dissection originates in the ascending aorta and propagates distally to the aortic arch and typically to the descending aorta with surgery usually recommended. Type II dissection originates in and is confined to the ascending aorta with surgery usually recommended. Type III dissection originates in the descending thoracic aorta and propagates most often distally with nonsurgical treatment usually recommended. The Stanford classification system is divided into type A dissections which involve the ascending aorta and type B dissections which do not involve the ascending aorta. Surgery is usually recommended for all dissections involving the ascending aorta. Surgery is usually not recommended for dissections that do not involve the ascending aorta.  Read more.............