6 Recommendations for further research
6.1 The following trials are currently ongoing.
The Elective Abdominal Aortic Aneurysm trial ACE is a French RCT comparing EVAR and OSR in patients aged 50 years and older with an AAA measuring 5 cm or more in diameter (4 cm or more if rapidly growing). The trial started in January 2003 with an expected completion date of January 2006. The date of publication has not been confirmed at present.
OVER (open surgery versus endovascular repair) is a large USA RCT comparing EVAR and OSR in patients aged 50 years and older with an AAA measuring 5 cm or more in diameter (4.5 cm or more if rapidly growing). The expected completion date is October 2011.
CAESAR (comparison of surveillance versus aortic endografting for small aneurysm repair) is an RCT in Italy to compare EVAR with surveillance (and eventual treatment) in patients with AAAs of diameter 4.1–5.4 cm who are suitable for EVAR. Results are expected at the end of 2011.
6.2 Further research is needed on the management of ruptured aneurysms. Given the difficulties of conducting RCTs on the management of ruptured aneurysms, the collection of data through existing, established registries, particularly RETA (for EVAR) and NVD (for OSR) in the UK should be continued.
6.3 Research is required to measure the extent to which the relative treatment effect of EVAR on operative mortality can be assumed constant across subgroups of patients.
6.4 Research is required into how to incorporate the best available risk-scoring systems for the management of AAA into decision-making in routine clinical practice.