Conversion from endoluminal to open repair of abdominal aortic aneurysms: a hazardous procedure

The purpose of this study was to analyse the technical problems associated with conversion from endoluminal repair of abdominal aortic aneurysms (AAA) to open repair and document the outcome in patients with this clinical course.

Between May 1992 and May 1996 endoluminal repair of AAA was undertaken in 113 patients. Forty-eight of these had medical co-morbidities which led to them being rejected for open repair at other medical centres. Conversion from endoluminal to open repair was required in 18 patients. Thirteen of these occurred at the original operation (primary conversion) and five occurred at a later operation (secondary conversion). Seven of the 18 patients undergoing conversion had serious medical co-morbidities. Three different methods of open repair were used. The technique selected was determined by the cause of failure leading to conversion. Standard open AAA repair was used in patients requiring conversion for access problems (n = 2) and balloon malfunction, where the device ended up entirely within the aneurysmal sac (n = 1). Modifications to the standard technique were required in patients in which the endograft was correctly positioned immediately below the renal arteries and/or where part of the endograft was within one or both common iliac arteries (n = 11). Supra-coeliac control was required for patients with aortic rupture (n = 1), renal arteries covered by the endograft (n = 2) and situations where the delivery catheter was trapped within the aorta above a twisted bifurcated graft (n = 1). The mean volume of contrast used was 225 ml and the mean operative time was 5.25 h in patients undergoing primary conversion.

Conversion to open repair was achieved in all 18 patients. Renal impairment requiring dialysis occurred in three patients. There were three perioperative deaths, all of which were procedure-related (17%), and one late death. All four deaths occurred from among the group of seven patients with preoperative co-morbidities.

Converting an endoluminal to an open AAA repair may require modifications to the standard open technique and result in a much higher than generally accepted morbidity and mortality rate. Patients rejected for open repair because of co-morbidities ran the same chance of requiring conversion as those without co-morbidities (15-17%). If conversion was required, however, they stood a 3 in 7 or 43% chance of dying.