Although the majority of DTAA are asymptomatic, all are potentially life-threatening because the natural course of DTAA is progressive dilatation with ultimate rupture.1 and 2 Ninety percent of ruptures result in death.1, 2 and 3
There is no known medical treatment for DTAA and, up until recently, the only known treatment was left thoracotomy and replacement of the aorta with prosthetic graft. The operative mortality for this procedure is approximately 10%.2 Alternatively, the average 3-year survival rate for patients with untreated DTAA is less than 25%.3, 4 and 5 Therefore, most physicians recommend surgical repair once the aneurysm reaches 6 cm. Unfortunately, the patients who have DTAA frequently have comorbidities such as chronic obstructive lung disease (COPD), coronary artery disease (CAD), or renal insufficiency that sometimes complicate conventional repair.6 and 7
Endovascular repair of DTAA provides an alternative to conventional repair. A stent-graft consists of a prosthetic Dacron or polytetrafluoroethylene graft attached to a stent. This stent-graft is then compressed and inserted into a slender tubular sheath, which can be passed over a guide wire and maneuvered up the femoral or iliac artery into the thoracic aorta with fluoroscopic guidance. The procedure is performed with the patient under spinal or epidural anesthesia. The technique is similar to that used for balloon angioplasty and stenting of coronary artery blockages. Retraction of the sheath allows the self-expanding stent to expand, seating the graft against the aortic wall. Once the endovascular graft is deployed, it provides a conduit for bloodflow and excludes the aneurysm sac from the general circulation, thereby preventing rupture.
Endovascular stent-graft repair (EVSG) of DTAA not only represents an exciting method of treating aneurysms but will demand new and challenging skills from the nurses involved in the care and treatment of patients undergoing this procedure. This type of repair also provides an opportunity for nurses to work collaboratively with physicians to provide optimum care and patient education.
This article describes and compares the conventional and endovascular repair of DTAA. It further describes the unique complications that can occur with the endovascular procedure and discusses the nursing implications for both the general and advanced practice nurse in the perioperative arena as well as in long-term follow-up.