Endovascular treatment of thoracic aortic aneurysms

Endovascular repair of thoracic aortic aneurysm

A thoracic aortic aneurysm (TAA) is a potentially life-threatening condition with structural weakness of the aortic wall, which can progress to arterial dilatation and rupture. Today, both an increasing awareness of vascular disease and the access to tomographic imaging facilitate the diagnosis of TAA even in an asymptomatic stage. The risk of rupture for untreated aneurysms beyond a diameter of 5.6 cm ranges from 46% to 74% and the two-year mortality rate is greater than 70%, with most deaths resulting from rupture. Treatment options include surgical and non-surgical repair to prevent aneurysm enlargement and rupture. While most cases of ascending aortic involvement are subject to surgical repair (partially with valve-preserving techniques), aneurysm of the distal arch and descending thoracic aorta are amenable to emerging endovascular techniques as an alternative to classic open repair or to a hybrid approach (combining debranching surgery with stent grafting) in an attempt to improve outcomes.

Outcome and quality of life after surgical and endovascular treatment of descending aortic lesions

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) represents an attractive alternative to open aortic repair (OAR). The aim of this study was to assess outcome and quality of life in patients treated either by TEVAR or OAR for diseased descending thoracic aorta.

METHODS

A post hoc analysis of a prospectively collected consecutive series of 136 patients presenting with surgical diseases of the descending aorta between January 2001 and December 2005 was conducted. Fourteen patients were excluded because of involvement of the ascending aorta. Assessed treatment cohorts were TEVAR (n = 52) and OAR (n = 70). Mean follow-up was 34 +/- 18 months. End points were perioperative and late mortality rates and long-term quality of life as assessed by the Short Form Health Survey (SF-36) and Hospital Anxiety and Depression Score questionnaires.

RESULTS

Mean age was significantly higher in TEVAR patients (69 +/- 10 years versus 62 +/- 15 years; p = 0.002). Perioperative mortality rates were 9% (OAR) and 8% (TEVAR), respectively (p = 0.254). Accordingly, cumulative long-term mortality rates were similar in both cohorts. Overall quality-of-life scores were 93 (63-110, OAR) and 83 (60-112, TEVAR), respectively. Normal quality-of-life scores range from 85 to 115. Anxiety and depression scores were not increased after open surgery.

CONCLUSIONS

Thoracic endovascular aortic repair and OAR both provide excellent long-term results in treatment of thoracic aortic disease. Long-term quality of life, however, is reduced after thoracic aortic repair. Interestingly, TEVAR patients did not score higher in overall quality of life despite all advantages of minimized access trauma. Similarly, anxiety and depression scores are not reduced by TEVAR, possibly reflecting a certain caution against the new technology.

The French National Authority for Health reports on thoracic stent grafts

OBJECTIVE

This study was conducted to determine the efficacy and safety of stent grafts in the treatment of thoracic aortic aneurysms and dissections.

METHOD

Our health technology assessment method combined a critical review of the literature with experts' opinions. Several databases, useful Web sites, and the gray literature were searched from January 1995 to December 2004. Some manually retrieved major articles published in 2005 were also included. The draft report was submitted to and discussed by a working group of 12 members nominated by relevant medical societies. The amended report was submitted to a multidisciplinary group of 12 peer reviewers for comment.

RESULTS

Endovascular stent grafting (ESG) repair for lesions of the thoracic aorta, including aneurysms, dissections, and aortic isthmus ruptures, is probably beneficial in terms of operative mortality and severe morbidity, with an incidence of paraplegia of 2.1% (range 0%-7%) for ESG vs 5% (range, 3%-15%) for surgery, provided that there is a rigorous medium-term assessment and that anatomic factors are favorable. A proximal neck length of at least 2 cm is needed to insert the stent graft. Indications for ESG in thoracic aortic aneurysm and dissection are similar to those for surgery. Endovascular stent grafting is particularly appropriate in patients with multiple traumas to the thoracic aorta in whom concomitant lesions are a contraindication to open surgery. Endovascular stent graft repair can only be done in public or private centers with expertise in both endovascular and surgical procedures and with adequate technical facilities. Patients should be informed of the advantages and drawbacks of both methods. A multidisciplinary discussion should address risks of converting to open surgery and possible need for a cardiopulmonary bypass. Patients should be monitored annually by computed tomography scan or magnetic resonance imaging and plain radiographs because long-term results are uncertain (possible stent graft deterioration, onset of aortic disease). They should be told of the need for surveillance and possible further treatment.

CONCLUSIONS

A prospective registry of all thoracic aorta procedures (endovascular treatment, open surgery, thoracic ESG plus extra-anatomic bypass) needs to be set up. All practitioners and stent graft manufacturers should contribute to this registry. It should include information on patient monitoring in order to (1) select patients who could be treated by ESG repair, (2) assess the feasibility of a randomized controlled study comparing ESG and surgery, (3) assess the medium-term outcome of different devices, and (4) obtain a better understanding of the health economics aspects.

Secondary Interventions after Elective Endovascular Repair of Degenerative Thoracic Aortic Aneurysms: Results of the European Collaborators Registry (EUROSTAR)

PURPOSE

The need for secondary interventions is an important indicator of intermediate and long-term success of endovascular repair of degenerative thoracic aortic aneurysm. The purpose of this study was to analyze the occurrence and consequences of secondary procedures.

MATERIALS AND METHODS

Data from 213 patients electively subject to operation for degenerative thoracic aortic aneurysm and achieving primary success and who were enrolled in the EUROSTAR registry were analyzed. Secondary procedures were categorized as follows: transfemoral endovascular reintervention, extraanatomic secondary procedures, and transthoracic surgery.

RESULTS

Overall, 25 (12%) of the patients with an elective treatment for a degenerative thoracic aneurysm had secondary intervention, occurring at a mean of 8 months after the initial procedure. Seventeen (68%) of the secondary interventions were via a transfemoral approach, six (24%) involved a transthoracic procedure, and two (8%) involved extraanatomic bypass. The cumulative percentage of freedom from intervention at 1 and 2 years was 86% and 83%, respectively. Endoleak (relative risk, 5.21) was the most frequent cause for secondary transfemoral intervention. For the other secondary interventions, no principal indication for reintervention could be identified. Patients who needed secondary interventions more frequently suffered from preoperative back pain (20% vs 44%, P = .008), and their thoracic aneurysms had a longer length (mean, 95.6 mm vs 133.2 mm, P = .006). The 2-year cumulative survival rate of patients without secondary intervention was 85% compared with 58% in the patients who received secondary intervention (P = .0001).

CONCLUSIONS

Regular surveillance after endovascular degenerative thoracic aneurysm repair is needed as secondary interventions were required throughout the follow-up period.

Early outcomes after elective and emergent endovascular repair of the thoracic aorta

BACKGROUND

Endovascular treatment of thoracic aortic pathology has emerged as a viable alternative to open surgical repair in both the elective and emergent settings. The aim of this study was to evaluate preoperative work-up, intra-operative strategy, and outcomes of endovascular stent-grafting of the thoracic aorta in patients undergoing elective repair and those undergoing emergent repair.

METHODS

All patient information was obtained by a retrospective review of an established clinical database for all endovascular thoracic stent-graft cases. From October 1999 to August 2005, 70 patients were treated with endovascular stent-grafts for lesions of the thoracic aorta. Thirty-five patients had an elective endovascular procedure, and 35 patients had an emergent procedure.

RESULTS

Thirty-five patients in the endovascular (EL) group were treated for aneurysm (n = 34) and type B dissection (n = 1). Thirty-five patients in the emergent (EM) group were treated for aneurysm (n = 10), intramural hematoma (n = 10), type B dissection (n = 7), traumatic rupture (n = 7), and aortoesophageal fistula (n = 1). Preoperative angiography was performed in 94.3% (33/35) of EL patients but in only 45.7% (16/35) EM patients (P < .005). The EM procedures had significantly shorter operative times, used lower contrast volumes, used fewer stent-graft components (mode 2, range 1 to 5 vs mode 1, range 1 to 3; P = .02), and spinal cerebrospinal fluid drains were used significantly less often (82.9% vs 57.1%, P = .04). Both groups had similar 30-day morbidity, mortality (0/35 EL vs 1/35 [2.9%] EM, P = .99), postoperative endoleak (9/35 [25.7%] EL vs 7/35 [20.0%] EM, P = .78), endovascular failure (3/35 [8.6%] EL vs 5/35 [14.3%] EM, P = .71), and patient survival.

CONCLUSION

There are significant differences in the underlying pathology, preoperative evaluation, and operative course between elective and emergency treatment endovascular procedures for lesions of the thoracic aorta. Endovascular repair of thoracic aortic lesions can be accomplished with low perioperative mortality and morbidity rates, as well as acceptable endoleak and endovascular failure rates for both elective and emergency procedures.

Endovascular repair of the descending thoracic aorta: evidence for the change in clinical practice

The purpose was to review outcome data following endovascular repair of the descending thoracic aorta from reports published between 1994 and 2004. To accomplish this task, 1,518 patients underwent endovascular repair for thoracic aortic disease; 810 thoracic aortic aneurysms, 500 type B thoracic aortic dissections, and 106 traumatic ruptures. The 30-day mortality rate was 5.5% and 6% for late postoperative deaths. The primary technical success rate was 97%, with only 15 patients requiring open conversion. Neurologic deficits occurred in 29 patients. In total, 118 endoleaks were reported; 29 were restented, and the remainder required surgical intervention. Graft infection occurred in 6 cases, and migrations were detected in 10. The conclusion reached is that endovascular repair of descending thoracic aortic disease is feasible and can be achieved with low rates of perioperative morbidity and mortality. As few long-term data exist on the durability of thoracic stent grafts, lifelong surveillance remains necessary.

Single Center Experience with a New Commercially Available Thoracic Endovascular Graft

PURPOSE

To evaluate the intra-operative performance and clinical outcome of a new commercially available stent-graft for the treatment of thoracic aortic diseases.

METHODS AND PATIENTS

From January 2003 to October 2004, 45 consecutive patients received endovascular treatment with the Zenith TX1 device for diseases of the thoracic aorta at a single center in northern Italy. Indications included disease of the descending thoracic aorta in 26 cases, of the aortic arch in 17 cases and of the thoraco-abdominal aorta in two cases. We treated 38 atherosclerotic aneurysms, two post-traumatic aortic ruptures, two penetrating ulcers, two chronic dissections and one case was treated for aortic bleeding after voluntary acid ingestion for attempted suicide. General anesthesia was used in 20 cases. Combined or hybrid endovascular and open surgical repair was performed in 11 patients. Mean follow-up was 7 months (range 1-22 months).

RESULTS

Technical success was obtained in 44 patients (98%). One primary type I endoleak occurred (2%). ICU was used in 12 cases with a mean stay of 1 day. The mean hospital stay was 6 days (range 4-13 days). There were no hospital deaths or strokes but one transient paraplegia (2%). A type II endoleak was observed in one case and resolved spontaneously 1 month later. No aneurysm enlargement, endograft migration or structural failures were observed during follow-up. Two late unrelated-deaths were observed.

CONCLUSIONS

This stent-graft does not fulfill all the characteristics of the ideal graft, however, it proved to be safe and allowed satisfactory short term results in this group of patients treated at a single center.

CT and MR imaging of the thoracic aorta: current techniques and clinical applications

Disease of the thoracic aorta can present with a broad clinical spectrum of symptoms and signs. The accepted diagnostic gold standard, selective digital subtraction angiography, is now being challenged by state-of-the-art CT angiography (CTA) and MR angiography(MRA). Currently, in many centers, cross-sectional imaging modalities are being used as the first line of diagnosis to evaluate the cardiovascular system, and conventional angiography is reserved for therapeutic intervention. Understanding the principles of CTA and MRA techniques is essential to acquire diagnostic images consistently. This article reviews current CTA and MRA methods used in the evaluation of thoracic aortic disease.