Endovascular aortic aneurysm repair by a multidisciplinary team: Lessons learned and six-year clinical update
Background: Endovascular aneurysm repair (EVAR) (using an Federal Drug Association-approved AneuRx® device) compared to conventional surgical repair of abdominal aortic aneurysm (AAA) previously rendered favourable outcomes regarding post-operative pain, avoidence of laparotomy, and rapid rehabilitation and hospital discharge in high-risk patients, including octagenarians. Objectives: To assess the safety, reduction in aneurysm-related deaths, and interim survival data up to 72 months after AAA exclusion by endoluminal endografts (EVAR). Design: We carried out an open, controlled, prospective, multidisciplinary EVAR study for the period 1998 to 2003 (six years). In the earlier part of the study, EVAR was compared with previously published results of conventional open aneurysmectomy surgery. Setting: Heart Unit, Panorama Medi-Clinic, Parow, South Africa. Participants: We recruited adult male and female patients presenting with AAA and fulfilling the inclusion criteria for endovascular repair, as recommended by the consensus 2003 meeting of the Vascular Association of South Africa (VASSA). All patients were offered open surgery as an alternative and were entered into the VASSA EVAR trial registry. Pre-operatively, AAA anatomy was assessed by spiral-computed tomography (CT), and selectively with conventional angiography and intravascular ultrasound (IVUS). Informed consent was obtained in accordance with the recommendations of the Senate of Surgery Paper 2, Ethical Guidelines, Great Britain and Ireland. Patients underwent EVAR by a multidisciplinary interventional team. Interventions: Two hundred and seven adult patient with AAA were assessed. Forty-four of the 207 (21.2%) were excluded from EVAR because of irreversible comorbid factors and complex aneurysm morphology. One hundred and sixty-three patients with a mean age of 70.7 years (range 60-91 years), underwent EVAR (1993-2003). Five patients were lost to follow-up (3%). Median AAA diameter was 56.9 mm and ASA ratings were I, 1.2%; II, 15.9%; III, 57%; IV, 22.6% and V, 2.4%. EVAR was performed in high- and low-risk categories of both sexes. Most patients were in ASA groups III and IV. Device deployed: EVAR was performed using a selection Of endografts over 72 months - AneuRx® (Medtronic) 47; Talent® (Medtronic) 49; Vanguard® three; Zenith® (Cook) one; Powerlink® (Endologix) 62; and other, one. Results: Thirty-day outcome: successful deployment 99%, primary stent patency 97%, surgical conversion 0.6%, procedural or intra-operative mortality 1.2%, 30-day mortality 4.3%, endoleaks 1.84%, and secondary intraprocedural endovascular interventions 24.5%. Peri-operative mortality was 3.1% (one aneurysm related). One patient had suspected endograft infection. Late mortality was 21.4% (35 patients due to co-morbidities, and one was aneurysm related). Follow-up was a median of 28.3 months (range 1-69 months). In 163 patients, two persisting endoleaks (1.2%) were detected. Endotension was detected in 3/163 (1.8% with average sac increase of 0.8 cm. Conversion to open surgery was needed in one patient (0.6%). Co-morbidities that contributed to late mortality included multi-organ failure, ischaemic heart disease (IHD), cardiomyopathy, renal failure, stroke and cancer. One procedural rupture was fatal (0.6%). Two late ruptures occurred; one was successfully endostented and the other patient died after a failed surgical intervention (0.6%). Endovascular repair of AAA is more expensive than conventional surgery. Introduction of the Endologix stent has reduced operative time from 120 to 60 minutes in uncomplicated patients. Newer-generation aortic stents allow better control of negative remodeling and stent migration. Conclusion: A multidisciplinary team can safely perform EVAR, with a low 30-day mortality rate in selected patients graded ASA II-IV and with favourable aortic aneurysm morphology. About 22% of patients with AAA are not suited for EVAR. Persisting late endoleaks occurred in 1.2% of the cohort study and were not device specific. Life-long follow-up post EVAR is a prerequisite to detect late device failure, endoleaks and aneurysm-sac enlargement, and to assure the durability of these mid-term results. Short-term aneurysm rupture prevention is a predictable outcome in high-risk groups.