Feasibility of emergency endovascular aneurysm repair, eEVAR has been discussed at the Eurostar collaborators meeting and also at the recent British Society of Interventional Radiology (BSIR) in Glasgow and at the Vascular Surgical Society of Great Britain & Ireland (VSSGBI). At the first of these, European experience was taken into account and at the British meetings there was an opportunity to discuss, with the EVAR trialists, radiological and vascular surgical, and coordinators, whether it was time to address emergency EVAR formally.
There were inevitably more questions than answers but at the BSIR and VSSGBI it was reiterated that, in the UK, EVAR is the domain of surgeons and radiologists in combination. It emerges that this is not necessarily the situation in some of the other European countries. A big question is whether there is time for a CT scan or not. There certainly was no total agreement amongst vascular surgeons whether CT scan should be performed in all cases of emergency aortic aneurysm. The general consensus was that a CT scan is the only reliable way of assessing suitability for EVAR, and 3-dimensional imaging reconstructions are the best way to avoid anatomical surprises. The question is whether all this is available around the clock, and the issue arose whether endovascular repair can be scheduled following angiography only.
There was clear benefit expressed for approaching contained rupture with CT scan and then the vascular repair under local anaesthetic, if time permitted. In all of these discussions it became plain that a pragmatic decision needed to be taken as to whether the patient was stable enough for a CT scan or not. It therefore seemed to fall into two categories; ones stable and able to have a CT scan and those deemed so unstable not to be suitable for CT scan. The next question was whether the patient would be anatomically suitable for endovascular repair. There was a variety of data coming from Nottingham, who have shown great interest in this subject. Brian Hopkinson, in Istanbul, commented that 90% of patients should be suitable for endovascular repair, but at the BSIR meeting, radiologists from Nottingham said that the number was down to 20%. Peter Harris announced great interest from the UK EVAR centres and, on behalf of the Trial Management Committee, Peter was asked to sound out interest levels. It became clear that at least 20 centres would wish to participate in a coordinated approach to emergency endovascular aneurysm repair. Suddenly in Istanbul, Brian Hopkinson announced that Nottingham had started its own REVAR Trial by Bruce Braithwaite and Shane McSweeney. The experience of Nottingham, since the first UK patient for emergency aneurysm was described by Yusef et al in 1994, is very important and greatly appreciated. Nottingham is working with William Cook and is recommending the use of the new BIFAB system. It seems to be a serious contender for emergency aneurysm repair with an aorto-uni-iliac system. It also emerges that the Medtronic aorto-uni-iliac device is being tested in Holland. The Cook device is seeking a CE mark by March 2003 and is already well known to the Medical Devices Agency in the UK. At the time of writing, the MDA have no information about the Medtronic device, although the Dutch trials are intending to further develop experience with this Medtronic device.
It is imagined that approximately 50% of aneurysms will be anatomically suitable and we must find out in a pilot study. The big question is whether there should be a pilot audit or go into a pilot trial from the beginning. There is much to be learned and the question is whether to consider randomisation in the very beginning of the learning curve.
The general feeling is that the UK surgeons wish to collaborate amongst some 20 centres and the NHS Research & Development Health Technology Assessment Programme, which funds the EVAR trials, have indicated support for a modification of the EVAR protocol to incorporate an eEVAR arm of the EVAR trials for recruitment during the calendar year of 2003. The NHS also indicated its willingness to fund the devices during this period. The aim will be to build upon the skills and knowledge of the Nottingham group to perform a pilot trial during that calendar year to begin as soon as possible. The precise algorithm and protocol was discussed at length and the accent was to stress that the period is a pilot. From the outset we can consider all of the various outcomes but the key will be to document the outcome of every patient who arrives at one of the designated centres during the calendar year of 2003 and comment on outcome of this highly fatal condition. Another aim of the study will be to identify those who are anatomically suitable for EVAR and to randomise half of them for open repair and half for endovascular repair.
The potential for a pilot eEVAR trial in the UK is viewed against the background of the knowledge of the outcome of the condition from recent UK Small Aneurysm Trial data published in Annals of Surgery 1999. From these data it was realised that 75% of patients died before reaching hospital and of the 25% who arrived alive, only half of those reached the operating theatre alive. It is the 25% that we need to look at and ask what is the best algorithm and protocol for management of these patients and whether endovascular repair comes into the picture. Any pilot information would require modification during the pilot phase. Peter Harris is remarkably energetic in seeking national enthusiasm for this collaboration. With his enthusiasm, and the experience of the Nottingham centre, we hope to proceed to the next stage.
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