One discussion this week included open vs endovascular repair for ruptured AAA.

Reference: IMPROVE trial investigators. Comparative clinical effectiveness and cost effectiveness of endovascular strategy v open repair for ruptured abdominal aortic aneurysm: three year results of the IMPROVE randomised trial. BMJ. 2017 Nov 14;359:j4859. doi: 10.1136/bmj.j4859

Trial registration: Current controlled trials ISRCTN48334791; ClinicalTrials NCT00746122.

Summary: Involving 30 vascular centers – 29 in UK, one in Canada – and 613 patients between 2009 and 2016, the IMPROVE trial is the first RCT comparing keyhole endovascular aneurysm repair to the traditional open surgery with comprehensive mid-term outcomes. The primary outcome was mortality; secondary outcomes included reinterentions, quality of life, resource use, consts, quality adjusted life year (QALYs), and cost effectiveness.

The data analyses showed endovascular repair “offers no significant reduction in operative mortality at 30 or 90 days, but there is an interim midterm survival advantage (3 months to 3 years), that when taken together with the early gains in QoL, leads to a mid-term gain in QALYs after 3 years.

• Mortality: 179 deaths in endovascular group, 183 in open repair, with similar results for mortality related to aneurysm
  • Of the 502 patients treated for confirmed rupture, mortality at 3 years: 109/259 (42%) in endovascular, 131/243 (54%) in open repair
• Reinterventions related to aneurysm: occured at similar rate in both groups, especially those for life threatening conditions.
• Cost differences at 30 days: “not erorded by an increased burden of reinterventions in later follow-up and therefore the endovascular strategy is cost effective” (p.7).

The authors conclude that at three years, the endovascular repair “offers an increase in QALYs, without an excess of reinterventions, and is cost effective” (p.9). The IMPROVE trial mid-term follow-up supports the benefits of endvascular vs open repair to treat ruptured AAA.

Table 5 (p.8) compares the mid-term outcomes from multiple RCTs of endovascular vs open repair for AAA, including the IMPROVE trial.

Additional reading: Bjorck M. Endovascular or open repair for ruptured abdominal aortic aneurysm? BMJ. 2017;359:j5170. doi:10.1136/bmj.j5170.