Re: Endovascular or open repair strategy for ruptured abdominal aortic aneurysm: 30 day outcomes from IMPROVE randomised trial
The clinical question addressed by the IMPROVE trial was what is the best management strategy for a patient with the clinical diagnosis of ruptured aneurysm [1]. The advantage of the IMPROVE trial design is that it represents the real life situation. It is this trial, not AJAX [2] or the similar French ECAR trial [3], which shows that CT scans did not introduce dangerous delays in the treatment pathway, reports the number of patients who died before definitive treatment could be offered as well as those who could not wait for endovascular repair to be organised. In the IMPROVE trial 28 patients randomised to the endovascular strategy and having aortic morphology suitable for endovascular repair were crossed over to open repair because of deteriorating patient condition or because the facilities and teams for endovascular repair were not yet available. The IMPROVE trial has shown that when endovascular repair was performed the 30-day mortality was 25%, versus 37% for open repair, but this comparison is likely to be biased by the selection of patients for each operation.
The organisation of the teams and facilities for endovascular repair is more complex than for open repair and takes longer. This delay may have adverse effects, although the often quoted figure that the early mortality increases by 3% per hour in the first 6 hours between rupture and definitive repair has no firm evidence to support it. In all three recent trials AJAX, IMPROVE and ECAR the average time taken for a patient to reach endovascular repair was longer than for a patient to reach open repair by almost 30 minutes, 10 minutes and over an hour respectively.
The pre-specified subgroups selected for analysis were limited, since the trial has insufficient power for numerous subgroup analyses. However, other analyses such as the impact of aortic morphology on survival after both endovascular and open repair, the impact of time between clinical diagnosis and repair as well as individual patient meta-analysis of the three European trials are in progress.
References
1 IMPROVE trial investigators. Endovascular or open repair strategy for ruptured abdominal aortic aneurysm: 30-day outcomes from the IMPROVE randomised trial. BMJ 2014;348:f6771
2 Reimerink JJ, Hoornweg LL, Vahl AC, Wisselink W, van den Broek TA, Legemate DA et al. Endovascular repair versus open repair of ruptured abdominal aortic aneurysms: a multicentre randomized controlled trial. Ann Surg 2013;258:248-56
3 Desgranges P for the ECAR investigators. Latest news from the ECAR randomised controlled trial. Presented at Veith Symposium, New York November 2013 and Controversies & Updates in Vascular Surgery, Paris January 2014, meetings.
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Re: Endovascular or open repair strategy for ruptured abdominal aortic aneurysm: 30 day outcomes from IMPROVE randomised trial
The clinical question addressed by the IMPROVE trial was what is the best management strategy for a patient with the clinical diagnosis of ruptured aneurysm [1]. The advantage of the IMPROVE trial design is that it represents the real life situation. It is this trial, not AJAX [2] or the similar French ECAR trial [3], which shows that CT scans did not introduce dangerous delays in the treatment pathway, reports the number of patients who died before definitive treatment could be offered as well as those who could not wait for endovascular repair to be organised. In the IMPROVE trial 28 patients randomised to the endovascular strategy and having aortic morphology suitable for endovascular repair were crossed over to open repair because of deteriorating patient condition or because the facilities and teams for endovascular repair were not yet available. The IMPROVE trial has shown that when endovascular repair was performed the 30-day mortality was 25%, versus 37% for open repair, but this comparison is likely to be biased by the selection of patients for each operation.
The organisation of the teams and facilities for endovascular repair is more complex than for open repair and takes longer. This delay may have adverse effects, although the often quoted figure that the early mortality increases by 3% per hour in the first 6 hours between rupture and definitive repair has no firm evidence to support it. In all three recent trials AJAX, IMPROVE and ECAR the average time taken for a patient to reach endovascular repair was longer than for a patient to reach open repair by almost 30 minutes, 10 minutes and over an hour respectively.
The pre-specified subgroups selected for analysis were limited, since the trial has insufficient power for numerous subgroup analyses. However, other analyses such as the impact of aortic morphology on survival after both endovascular and open repair, the impact of time between clinical diagnosis and repair as well as individual patient meta-analysis of the three European trials are in progress.
References
1 IMPROVE trial investigators. Endovascular or open repair strategy for ruptured abdominal aortic aneurysm: 30-day outcomes from the IMPROVE randomised trial. BMJ 2014;348:f6771
2 Reimerink JJ, Hoornweg LL, Vahl AC, Wisselink W, van den Broek TA, Legemate DA et al. Endovascular repair versus open repair of ruptured abdominal aortic aneurysms: a multicentre randomized controlled trial. Ann Surg 2013;258:248-56
3 Desgranges P for the ECAR investigators. Latest news from the ECAR randomised controlled trial. Presented at Veith Symposium, New York November 2013 and Controversies & Updates in Vascular Surgery, Paris January 2014, meetings.
Competing interests: No competing interests