Time-to-event data meta-analysis of late outcomes of endovascular versus open repair for ruptured abdominal aortic aneurysm.

Abstract

OBJECTIVE\nTo investigate whether the well documented perioperative survival advantage of emergency endovascular aneurysm repair (EVAR) over open repair is sustained in follow-up.\n\n\nMETHODS\nA systematic review conforming to the PRISMA statement standards was conducted to identify studies that reported follow-up outcomes of endovascular versus open repair for ruptured abdominal aortic aneurysm. Electronic bibliographic sources (MEDLINE, EMBASE, CINHAL, and CENTRAL) were interrogated using the Healthcare Databases Advanced Search interface. A time-to-event data meta-analysis was performed using the inverse-variance method and the result was reported as summary hazard ratio (HR) and associated 95% confidence intervals (CI). Mixed effects regression was applied to investigate outcome changes over time. The quality of the body of evidence was appraised using the GRADE system.\n\n\nRESULTS\nThree randomized controlled trials (RCTs) and 22 observational studies reporting a total of 31,383 patients were included in quantitative synthesis. The mean duration of follow-up ranged across the studies from 232 days to 4.9 years. The overall all-cause mortality was significantly lower after EVAR than after open repair (HR 0.79, 95% CI 0.73-0.86), but the post-discharge all-cause mortality was not significantly different (HR 1.10, 95% CI 0.85-1.43). The aneurysm related mortality, that was reported by one RCT, was not significantly different between EVAR and open repair (HR 0.89, 95% CI 0.69-1.15). Meta-regression showed the mortality difference in favour of EVAR was more pronounced in recent studies (P=0.069) and recently treated patients (P=0.062). The certainty for the body of evidence for overall and post-discharge all-cause mortality was judged to be low, and for aneurysm-related mortality it was high.\n\n\nCONCLUSIONS\nEVAR has a sustained mortality benefit in follow-up over open repair. A wider adoption of an endovascular-first strategy is justified.