Expanding Role of Endovascular Repair for Type B Aortic Dissection

Abstract

Aortic dissection is a medical emergency that can quickly lead to death, despite optimal treatment. The Stanford classification is widely used and is in close relationship to clinical practice, as type A dissections require primary surgical repair whereas type B dissections are treated medically as initial treatment with surgery or endovascular repair (EVR) reserved for any complications. Multislice CT is the investigation of choice to establish the diagnosis and plan treatment strategies. Therapeutic strategies differ for treatment of an acute dissection compared with a chronic dissection. Traditionally, most institutions favor a “complication specific” approach for type B dissection with antihypertensive treatment and use of β-blockers as primary therapy. Surgery or EVR is reserved for patients with recurrent pain, life-threatening complications, or rapid aortic expansion. With above algorithms, there is evidence that 30 to 50% patients on conservative therapy develop serious morbidity or mortality over 5-year period. Clinical and imaging markers of adverse outcome are being identified to revise the management strategies and offer EVR to those at risk for adverse outcome. This is especially relevant in view of the fact that EVR for type B dissection is associated with procedural success in 99.2 ± 0.1% patients. Overall survival rates of 96.9% at 30 days, 96.7% at 6 months, 96.4% at 1 year, 95.6% at 2 years, and 95.2% at 5 years are reported after EVR in type B dissections. There is emerging evidence that EVR may be noninferior to surgery in this group of patients. These observations along with the development of dissection-specific device designs have the potential to rewrite the management algorithms for type B aortic dissection and define the role of EVR in this disease.