Immediate Management of the Patient With Ruptured Aneurysm: Open Versus Endovascular Repair | Clinical Trial - IMPROVE


The goal of this trial was to compare long-term outcomes following endovascular versus open surgical repair of ruptured abdominal aortic aneurysms (AAAs).

Contribution to the Literature: The IMPROVE trial demonstrates that 1-year mortality following ruptured AAA repair is similar between endovascular and open repair, but among survivors, endovascular repair may be associated with better quality of life scores, and is also more cost-efficient.

Study Design

Patients with an in-hospital diagnosis of a ruptured AAA were randomized to either an endovascular strategy of immediate computed tomography angiography and emergent endovascular aneurysm repair (EVAR) (n = 316) if anatomically feasible, or to emergent open repair (n = 297).

Inclusion criteria:

  • Age >50 years
  • Clinical diagnosis of ruptured AAA or ruptured aortoiliac aneurysm
  • For EVAR: Aneurysm neck diameter ≤32 mm, aneurysm neck length ≥10 mm, and neck angulation <60 degrees
  • Total number of enrollees: 613
  • Duration of follow-up: 1 year
  • Mean patient age: 76.7 years
  • Percentage female: 22%
  • Mean aneurysm diameter: 8.4 cm
  • Admission systolic blood pressure: 110 mm Hg

Principal Findings:

Of the 613 randomized patients, 536 (87.4%) had proved AAA rupture; repair was started in 502 (93.6%) of these patients. Primary outcome: Mortality at 1 year for endovascular vs. open strategy: 41.1% vs. 45.1% (p = 0.33). The majority of mortality was either in-hospital or within 30 days (35.4% vs. 37.4%).

Secondary outcomes: Among patients with an attempted repair, reintervention rates were similar: 21.2% vs. 20.2% (p = 0.7). Average length of stay: 17 vs. 26 days (p < 0.001). Quality of life, as assessed by EQ-5D, was higher in the EVAR arm among surviving patients at 3 months: 0.76 vs. 0.67, p < 0.05, and 12 months: 0.77 vs. 0.71, p < 0.05. Quality-adjusted life-year gain at 1 year with EVAR was 0.052. Total costs were lower: £16,394 vs. £18,723.


The results of this trial indicate that among patients with ruptured AAA, mortality at 1 year remains high, with the highest risk within the first 30 days. EVAR did not provide a survival advantage over open surgery, although among survivors, it appeared to be a more cost-efficient strategy. The lack of mortality benefit with EVAR is similar to that observed in the DREAM and AJAX trials. Current guidelines list a Class I indication for both endovascular or open surgical repair in patients with ruptured AAA, with EVAR being preferred in hospitals with available expertise and where computed tomography angiography suggests a favorable anatomy.


Grieve R, Gomes M, Sweeting MJ, et al. Endovascular strategy or open repair for ruptured abdominal aortic aneurysm: one-year outcomes from the IMPROVE randomized trial. Eur Heart J 2015;Apr 8:[Epub ahead of print].

Clinical Topics: Cardiac Surgery, Invasive Cardiovascular Angiography and Intervention, Noninvasive Imaging, Vascular Medicine, Aortic Surgery, Interventions and Imaging, Interventions and Vascular Medicine, Angiography, Nuclear Imaging

Keywords: Aneurysm, Ruptured, Aneurysm, Angiography, Aortic Aneurysm, Abdominal, Aortic Rupture, Blood Pressure, Cardiac Surgical Procedures, Endovascular Procedures, Follow-Up Studies, Length of Stay, Quality of Life, Survivors, Tomography

< Back to Listings