Perspective: The following are 10 points to remember from the American Heart Association (AHA) Scientific Statement on surgical management of descending thoracic aortic disease (TAD).
1. Descending TAD is increasingly recognized, composed of distinct etiologies with predictable and well defined clinical behaviors.
2. Historically, surgical intervention for descending TAD has been associated with high rates of paraplegia and mortality. However, in recent years, particularly at high-volume centers, mortality (4-9%) and paraplegia (<3%) rates have improved. 3. Endovascular thoracic aortic stent grafts are an attractive treatment option in descending TAD due to lower published risks of mortality and paraplegia, particularly in the high surgical risk groups (i.e., the elderly and those with significant chronic obstructive pulmonary disease). 4. Though technically feasible in a variety of clinical settings, some considerations for the broad application of stent grafting in descending TAD include: * Lack of long-term data on durability (>5 years).
* Lack of prospective randomized trials to directly compare open and endovascular therapy.
* Re-intervention rates, primarily for endoleak, are not insignificant.
* Risk of stroke approaches 4%.
* Frequent need for left subclavian bypass procedures in order to secure adequate landing zones.
5. Patients with the Marfan syndrome or other connective tissue diseases were excluded from stent-graft trials and are not ideal candidates for stent grafting.
6. Though feasible in most cases, stent graft therapy of thoracic aortic aneurysm should not be performed at aortic sizes smaller than what is recommended for traditional surgery. Patient selection should be based on lack of candidacy for open surgery, life expectancy, and anatomic suitability.
7. Traditional surgery for complicated acute type B dissection carries significant morbidity and mortality. Endovascular therapy is emerging as an alternative with high rates of technical success, false lumen thrombosis, and low complication rates.
8. Prophylactic stent grafting to prevent complications of chronic type B dissection is compared to medical management in the INSTEAD and ABSORB trials, but long-term data are not yet available.
9. Stent grafting can be performed as an alternative to high-risk surgery in intramural hematoma and penetrating atherosclerotic ulcers (PAUs) in the descending aorta. Stent grafting of PAU is associated with higher complication rates due to the diffuse nature of atherosclerotic disease. The risk of endoleak is higher in these patients.
10. Treatment of traumatic aortic transaction with stent grafts is an alternative to surgery in high-risk cases. However, in this younger population, questions remain regarding graft durability, impact of frequent imaging, and radiation exposure, and long-term consequences of left subclavian coverage (required in an estimated 80% of cases). Anna M. Booher, M.D.