Hybrid versus conventional open surgical repair for thoracic aortic arch aneurysms

Background

An aortic aneurysm is an abnormal bulge or swelling that occurs in the wall of the aorta. An aneurysm can be classified by its shape, location (sometimes reported as zone) and size. A thoracic aortic arch aneurysm (TAA) is a swelling in the upper portion of the thoracic aorta. The estimated annual incidence (number of new cases in a population over a particular period of time) of TAAs is between 5.6 and 10.4 cases per 100,000 patient-years. TAAs affect people mostly in the sixth and seventh decade of life and affect men and women equally. Management of TAAs differs by the extent and location of the aneurysm along the aortic arch and the patient’s medical history. TAAs can be treated with either open surgical repair (a surgical procedure requiring partial or total replacement of the diseased aortic arch) or hybrid repair (a surgical procedure which is a less invasive form of open surgical repair). So far, there is no consensus on which type of operation offers the best clinical outcomes in people with TAAs.

This review aimed to assess the safety and effectiveness of hybrid repair compared to open surgical repair in treating TAAs.

Study characteristics and key results

We searched the literature for randomised controlled trials (RCTs) and controlled clinical trials (CCTs) to evaluate the effectiveness and safety of HR compared to OSR for treating TAAs. Our search, current up to March 2021, did not identify any trials that met our inclusion criteria. High-quality trials are needed to help inform healthcare professionals, policy makers, and patients about the best possible treatment option for people with TAAs.

Certainty of the evidence

We found no RCTs and CCTs that addressed the review objective.

Conclusion

High-quality RCT and CCTs are required to assess the safety and effectiveness of HR compared to OSR effectively.

Authors' conclusions: 

Due to the lack of RCTs or CCTs, we were unable to determine the safety and effectiveness of HR compared to OSR in people with TAAs, and we are unable to provide high-certainty evidence on the optimal surgical intervention for this cohort of patients. High-quality RCTs or CCTs are necessary, addressing the objective of this review.

Read the full abstract...
Background: 

Thoracic aortic arch aneurysms (TAAs) can be a life-threatening condition due to the potential risk of rupture. Treatment is recommended when the risk of rupture is greater than the risk of surgical complications. Depending on the cause, size and growth rate of the TAA, treatment may vary from close observation to emergency surgery. Aneurysms of the thoracic aorta can be managed by a number of surgical techniques. Open surgical repair (OSR) of aneurysms involves either partial or total replacement of the aorta, which is dependent on the extent of the diseased segment of the aorta. During OSR, the aneurysm is replaced with a synthetic graft. Hybrid repair (HR) involves a combination of open surgery with endovascular aortic stent graft placement. Hybrid repair requires varying degrees of invasiveness, depending on the number of supra-aortic branches that require debranching. The hybrid technique that combines supra-aortic vascular debranching with stent grafting of the aortic arch has been introduced as a therapeutic alternative. However, the short- and long-term outcomes of HR remain unclear, due to technical difficulties and complications as a result of the angulation of the aortic arch as well as handling of the arch during surgery.

Objectives: 

To assess the effectiveness and safety of HR versus conventional OSR for the treatment of TAAs.

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 ClinicalTrials.gov trials registers to 22 March 2021. We also searched references of relevant articles retrieved from the electronic search for additional citations.

Selection criteria: 

We considered for inclusion in the review all published and unpublished randomised controlled trials (RCTs) and controlled clinical trials (CCTs) comparing HR to OSR for TAAs.

Data collection and analysis: 

Two review authors independently screened all titles and abstracts obtained from the literature search to identify those that met the inclusion criteria. We retrieved the full text of studies deemed as potentially relevant by at least one review author. The same review authors screened the full-text articles independently for inclusion or exclusion.

Main results: 

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