Are patient outcomes superior after endovascular or open surgical repair of thoracoabdominal aortic aneurysms?


A thoracoabdominal aortic aneurysm (TAAA) is a widening or swelling of a blood vessel 50% greater than the original vessel diameter, affecting the thoracic and abdominal aorta simultaneously. A TAAA greater than 6.0 cm to 6.5 cm in diameter (depending on the gender of the patient, or the presence of an underlying inherited weakness in the aortic wall), or a TAAA expanding faster than 1 cm per year, is regarded as a life-threatening condition if left untreated, and presents a complex challenge for surgeons in deciding on the best treatment path for each patient. The treatment options include open surgical repair which requires the surgical team to open both the chest and the abdomen to replace the diseased aorta with a material graft; endovascular repair which involves inserting a series of stents covered with material (endografts) within the aneurysm through small groin incisions using X-rays to guide the endografts into place; and non-interventional management which requires counselling patients and their family and, when necessary, prescribing patients medications to control risk factors. Significant complications including death exist after endovascular and open surgical repair. However, endovascular repair is conceptually less invasive, and for this reason, we aimed to determine if endovascular repair is a safer option for patients compared to open surgical repair.

Study characteristics and key results

We searched the literature for randomised controlled trials and controlled clinical trials to evaluate the effectiveness and safety of endovascular compared to open surgical repair for treating thoracoabdominal aortic aneurysms. Randomised controlled trials and controlled clinical trials help inform healthcare professionals, policymakers, and consumers about the best possible treatment option for patients with TAAAs. These types of trials aim to control confounding factors, for example patient fitness or surgeon experience, so that the methods of treatment are fairly compared. Our search up to April 2021 did not identify any randomised controlled trials or controlled clinical trials that met our inclusion criteria.

Certainty of the evidence

We found no studies that addressed our objective.


To assess the safety and effectiveness of endovascular compared to open surgical repair effectively, randomised controlled trials and controlled clinical trials would be helpful, but there are logistical and ethical challenges in undertaking such trials.

Authors' conclusions: 

Due to the lack of RCTs or CCTs, we were unable to determine the safety and effectiveness of endovascular compared to OSR in patients with TAAAs and are unable to provide any evidence on the optimal surgical intervention for this cohort of patients. High-quality RCTs or CCTs addressing this objective are necessary, however conducting such studies will be logistically and ethically challenging for this life-threatening disease.

Read the full abstract...

Thoracoabdominal aortic aneurysms (TAAAs) are a life-threatening condition which remain difficult to treat. Endovascular and open surgical repair (OSR) provide treatment options for patients, however, due to the lack of clinical trials comparing these, the optimum treatment option is unknown.


To assess the effectiveness and safety of endovascular repair versus conventional OSR for the treatment of TAAAs.

Search strategy: 

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL and AMED databases and World Health Organization International Clinical Trials Registry Platform and trials registers to 26 April 2021. We also searched references of relevant articles retrieved from the electronic search for additional citations.

Selection criteria: 

We considered all published and unpublished randomised controlled trials (RCTs) and controlled clinical trials (CCTs) comparing endovascular repair to OSR for TAAAs for inclusion in the review. The main outcomes of interest were prevention of aneurysm rupture (participants without aneurysm rupture up to 5 years from intervention), aneurysm-related mortality (30 days and 12 months), all-cause mortality, spinal cord ischaemia (paraplegia, paraparesis), visceral arterial branch compromise causing mesenteric ischaemia or renal failure, and rate of reintervention.

Data collection and analysis: 

Two review authors independently screened all titles and abstracts identified from the searches to identify those that met the inclusion criteria. We planned to undertake data collection, risk of bias assessment, and analysis in accordance with Cochrane recommendations. We planned to assess the certainty of the evidence using GRADE.

Main results: 

No RCTs or CCTs met the inclusion criteria for this review.