CONVERSION FROM ENDOLUMINAL TO OPEN REPAIR OF ABDOMINAL AORTIC-ANEURYSMS - A HAZARDOUS PROCEDURE

Aim: The purpose of this study teas 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 w ith this clinical course. Methods: Between May 1992 and May 1996 endol uminal repair of AAA was undertaken in 113 patients. Forty-eight of th ese had medical co-morbidities which led to them being rejected for op en repair at other medical centres. Conversion From endoluminal to ope n repair was required in 18 patients. Thirteen of these occurred at th e 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 method s of open repair were used. The technique selected was determined by t he cause of failure lending to conversion. Standard open AAA repair wa s used in patients requiring conversion for access problems (n=2) and balloon malfunction, where the device ended up entirely within the ane urysmal sac (n=1). Modifications to the standard technique were requir ed in patients in which the endograft was correctly positioned immedia tely below the renal arteries and/or where part of the endograft was w ithin one or both common iliac arteries (n=11). Supra-coeliac control was required for patients with aortic rupture (n=1), renal arteries co vered by the endograft (n=2) and situations where the delivery cathete r 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 ti me was 5.25 h in patients undergoing primary conversion. Results: Conv ersion to open repair was achieved in all 18 patients. Renal impairmen t requiring dialysis occurred in three patients. There were three peri operative deaths, all of which were procedure-related (17%), and one l ate death. All four deaths occurred from among the group of seven pati ents with preoperative co-morbidities. Conclusions: Converting an endo luminal to an open AAA repair may require modifications to the standar d open technique and result in a much higher than generally accepted m orbidity and mortality rate. Patients rejected for open repair because of co-morbidities ran the same chance of requiring conversion as thos e without co-morbidities (15-17%). If conversion was required, however , they stood a 3 in 7 or 43% chance of dying.