Search

Endovascular treatment of thoracic aortic pathology (ETAP) has been under development for over a decade. Only recently has one device been approved in the United States for treatment of descending thoracic aortic aneurysms. The length of this development process is due to multiple device and deployment system modifications, as understanding has evolved of the unique challenges of reconstruction in the thoracic aorta. The TX2 system has evolved from pioneering custom-made designs into a mature system with several features designed to improve early and late results. Controlled trials are necessary to compare the outcomes of ETAP with standard open repair. This article will detail the current generation of the device, review large published single-center experiences, and describe an ongoing prospective, nonrandomized, multi-institutional, investigational device exemption (IDE) phase II pivotal clinical trial investigating the safety and effectiveness of this device in elective treatment of patients with descending thoracic aortic aneurysms.

Although open surgical repair of abdominal aortic aneurysms remains the standard of care, endovascular repair is becoming an attractive alternative as more long-term outcome data become available to show its safety and efficacy. The authors review data on the 2-year outcome of the pivotal US multicenter, prospective Gore Excluder Trial. Patients treated with the Excluder endograft (W.L. Gore, Flaggstaff, AZ) had less blood loss (310 +/- 19 v 1,590 +/- 124 mL; P <.0001), required fewer homologous transfusions (6% v 32%; P <.0001), and had faster inpatient recovery (2.0 +/- 0.1 v 9.8 +/- 1.4 days; P <.0001) compared with those treated with open repair. Early major adverse events were reduced significantly in the patients treated with the endograft (14% v 57% in control; P <.0001), and this persisted at 2 years. There was no difference in overall survival rate (P =.13). There were no deployment failures, early conversions, or aneurysm ruptures. At the 2-year time-point, trunk migration occurred in 1%, limb migration in 1%, limb narrowing in 1%, endoleak in 20%, and aneurysm growth in 14%. There was a 7% annual reintervention rate in the endograft group in the first 2 years. The Excluder endograft is a safe and effective treatment compared with open surgical repair for infrarenal abdominal aortic aneurysms with appropriate anatomy.

Early detection of abdominal aortic aneurysms potentially can save many lives by preventing aneurysm rupture. Screening programs, however, have yet to be proven as an efficient means of accomplishing this goal and improving overall life expectancy. Until more information is available, selective high-risk screening may be the only viable option. Recently, 2 large prospective studies have better defined the utility of screening programs and have provided guidelines for the safe nonoperative management of small aneurysms. Using ultrasound surveillance, these can be followed up at 3- to 12-month intervals, depending on their size, with operative intervention reserved for aneurysms that enlarge rapidly, become symptomatic, or reach 5.5 cm in diameter., (Copyright 2001 by W.B. Saunders Company)

Vena cava filtration devices are commonly inserted for the prevention of fatal pulmonary emboli. Several imaging methods are used today to direct device placement. Bedside insertion has several advantages, particularly in the critically ill patient. Imaging techniques include bedside fluoroscopy, transperitoneal ultrasound, and intravascular ultrasound. We have now successfully placed 10 transfemoral vena cava filters by use of intravascular ultrasound at the patient's bedside. This appears to be a feasible method for filter insertion.

Long-term follow-up of controlled clinical trials of endovascular grafting for aortic aneurysms will provide data on the safety and efficacy of this new treatment to reduce morbidity and mortality compared with standard treatment. It will be several years before this information will be available, and careful analysis of surrogate markers for clinical success has value for predicting long-term outcome. One essential surrogate marker is aortic aneurysm diameter, which has traditionally been the most important variable in calculating rupture risk, and multiple studies have shown that aneurysms shrink after complete endovascular exclusion. Furthermore, measurements of aortic neck size and aortic length has shown interesting patterns that may affect the durability of endovascular repair and, thus, may suggest potential strategies for the design of future devices.

Endovascular repair is a feasible treatment alternative with favorable short-term results compared with standard operations. Nonrandomized, multicenter trials already in progress should help to define the role of endovascular grafting in the treatment of patients who are otherwise candidates for conventional repair. Long-term follow-up studies will test the durability of the procedure, including clinical repercussions of late endoleaks and migration related to slow alterations in aortic morphology, such as neck dilation and aortic shortening. More research is needed into long-term aortic morphologic changes; further insights into these changes may allow subclinical prediction of clinical events and permit intervention before a catastrophic failure. How great an advantage this procedure has over observation in high-risk patients for whom no open surgical alternative is available is also unknown because the overall mortality of this patient cohort may mitigate any treatment benefits. In today's cost-conscious world, the viability of this new technology may be dependent on balancing the short-term benefits of this procedure against its associated requirements for monitoring and subsequent reinterventions.