[Endovascular therapy of abdominal aortic aneurysm: results of a mid-term follow-up].

PURPOSE: Prospective study to evaluate clinical results and complications of endovascular abdominal aortic aneurysm treatment in a mid-term follow-up.

MATERIALS AND METHODS: A total of 122 patients (9 females, 113 males, average age 70.9 +/- 7.9 years) with abdominal aortic aneurysms were treated with stent grafts (53 Vanguard or Stentor endografts, 69 Talent endografts). Group I consisted of 40 patients who had all aortic tributaries of the aneurysm sac occluded prior to endovascular grafting, either spontaneously by parietal thrombosis or by selective coil embolization of the respective ostia preserving collateral circulation distal to the vessel occlusion. Group II consisted of 82 patients and included all cases without or with incomplete coil embolization with at least one patent vessel. Stent grafting was performed in general anesthesia in the first 21 patients, followed by peridural anesthesia in 15 cases, and local anesthesia with conscious sedation in 86 cases. The results were evaluated with Spiral-CT, MRI and radiographs of the endovascular graft, with follow-up examinations obtained at 3, 6, 12 months, and every year.

RESULTS: Implantation was successfully completed in all cases without primary conversion surgery, laparotomy, or any significant complication. Mean follow-up was 29 +/- 21 months (maximum 84 months). The 30-day mortality was 0.8 % due to a myocardial infarction 3 days after discharge from the hospital. A total of 47 re-interventions were performed in 29 patients (23.8 %), with 35 re-interventions in 18 cases with Vanguard or Stentor endografts and 12 re-interventions in 11 patients with Talent endografts. 23 percutaneous re-interventions included distal graft extension (n = 11), Wallstents for kinking and limb stenosis (n = 3), and secondary coil embolization of collateral vessels (n = 9). 24 surgical re-interventions included proximal graft extension (n = 6), new endovascular grafts (n = 3), surgical clipping of lumbar and mesenteric artery branches for type-II endoleaks following ineffective secondary coil embolization (n = 1), and femorofemoral crossover bypasses (n = 4). A total of 10 secondary conversion operations were performed because of damage to the membrane (n = 4; 3 Vanguard endografts, 1 Talent endograft), significant caudal migrations (n = 5; 4 Vanguard endografts, 1 Talent endograft) associated with type-I endoleaks (n = 2), limb occlusion (n = 1), disconnection of graft components (n = 1), and significant endoluminal thrombus deposits (n = 1). One patient, who was followed for 82 months, suffered from a significant endoleak for 10 months with increasing aneurysm diameter but he refused surgery. He was admitted with aneurysm perforation and was successfully operated with aortic graft replacement. Compared to group II, the incidence and size of endoleaks was reduced in group I (incidence 19.2 % versus 29.9 %, p < 0.05). Group I demonstrated significantly better aneurysm shrinkage at 36 months follow-up (Delta sagittal diameter - 11.1 +/- 8.4 mm versus - 4.9 +/- 6.2 mm, p < 0.05).

CONCLUSION: In selected patients, endovascular aneurysm treatment is an effective alternative to open surgery. It is safely performed in local anesthesia with low mortality rate and a low number of acute complications. Intermediate follow-up revealed re-interventions in around one quarer of all patients, especially when Vanguard or Stentor endografts were implanted. Primary coil embolization of all aortic branches prior to endovascular grafting improves clinical outcome. Insufficient proximal fixation and its consecutive complications remains a major problem of this method.