Hybridverfahren zur therapie thorakoabdomineller aortenaneurysmen (TAAA). Erste erfahrungen an einem hochrisikokollektiv

Introduction. Open replacement of the aorta for treatment of thoracoabdominal aortic aneurysms (TAAA) is liable to complications. The combination therapy consisting in endovascular bypass of the TAAA and proximal/distal diversion of supraaortal vessels and of the visceral and renal arteries (debranching) could be a technical alternative for the high-risk patient. Patients and methods. We report on a consecutive prospective series of 47 patients with TAAA (29.8% female; median age 65.5 years, range 37-81 years; 44 in ASA stage >3). In 51% of cases the aneurysm was an arteriosclerotic TAAA, while in 38.3% a secondarily expanding type B aortic dissection was present and in 10.6%, a plaque rupture or a Carrel patch stretched by an aneurysm. Six patients (12.6%) were treated as emergencies because of a free or concealed aortic rupture; 21.3% had back pain, and 66% had no symptoms. In 55.3% and in 23.4% a TAAA affecting a long section of the aorta and classifiable as Cawford extents II or III, respectively, was present. The median maximum diameter of a TAAA in this series was 74 mm (range 45-120 mm), and 57.4% of the patients had already undergone surgery of the abdominal or thoracic aorta previously. In 7 patients (14.9%) proximal debranching was first performed to create a proximal landing area offset in time against the hybrid operation. In 51% of patients it was necessary to replace the infrarenal aorta with a prosthesis before a distal landing area could be created. The median duration of surgery was 368 min for the abdominal intervention and 499 (range 250-935) min for the entire procedure. All patients underwent clinical examination and spiral CT investigation at 6-month intervals with prospective documentation. Results. The 30-day mortality was 12.6% (6/47 patients) for the whole series and 7.4% (3/41) for those with nonruptured TAAA. The corresponding paraparesis/paraplegia rates were 4.2% and 8.5%. In 8.5% renal insufficiency requiring dialysis arose in the postoperative period. The mean length of stay in hospital was 21.3-26 (11-68) days and the mean length of stay in the intensive care unit, 9 (2-31) days. The postoperative CT investigation showed 11 endoleaks in 10 patients (type I n=6; type II n= 4; type III n=1) and 7 occluded bypasses (only renal arteries). Type I and II endoleaks were corrected by endovascular techniques. Conclusions. The hybrid operation is a technically and logistically challenging alternative to conventional thoracoabdominal aortic replacement for the high risk patient. To optimise the result, the procedure must be evaluated prospectively against the conventional standard treatment.