Anatomic suitability of ruptured abdominal aortic aneurysms for endovascular repair.Ann Vasc Surg. 2008 Nov; 22(6):716-22.AV
Mortality from ruptured abdominal aortic aneurysms (rAAAs) remains high despite improvements in anesthesia, postoperative intensive care, and surgical techniques. Recent small series and single-center experiences suggest that endovascular aneurysm repair (EVAR) for rAAAs is feasible and may improve short-term survival. However, the applicability of EVAR to all cases of rAAA is unknown. The purpose of this study was to investigate the anatomical suitability of ruptured aneurysms for EVAR as determined by preoperative cross-sectional imaging. A contemporary consecutive series of rAAAs presenting to a tertiary academic center was retrospectively reviewed. Preoperative radiographic imaging was reviewed and assessed for endovascular compatibility based on currently available EVAR devices. Patients with aneurysm morphology demonstrating neck diameter >32 mm, neck length <10 mm, neck angulation >60 degrees, severe iliac tortuosity, or external iliac diameter <6 mm were deemed noncandidates for EVAR. Forty-seven rAAAs were treated over a 10-year period, with 47% of patients presenting with free rupture and 60% of patients transferred from outside hospitals. Five (11%) patients were treated with EVAR, all over the past 2 years, while the remaining 42 patients underwent open repair. Preoperative imaging was available for review in 43 (91%) patients, and morphological measurements indicated that 49% would have been candidates for EVAR with currently available devices. Criteria precluding EVAR in this cohort were inadequate neck length in 73%, unsuitable iliac access in 23%, large neck diameter in 18%, and severe neck angulation in 14%. Overall 30-day mortality was 34%, and 1-year mortality was 42%. Candidates for EVAR were more likely than non-EVAR candidates to be male (95% vs. 68%, p = 0.046) and to have smaller sac diameters (7.0 vs. 8.5 cm, p = 0.02) and longer neck lengths (24.1 vs. 8.6 mm, p < 0.0001); less likely to have a >60 degree angulated neck (10% vs. 45%, p = 0.0002), larger external iliac diameter (8.9 vs. 7.3 mm, p = 0.015), and less blood loss during surgical repair (2.4 vs. 6.0 L, p = 0.02); and more likely to be discharged home (71% vs. 25%, p = 0.05). There were no differences in 30-day, 1-year, or overall mortality between candidates for EVAR and noncandidates. Only 49% of patients with rAAAs in this consecutive series were found to be candidates for EVAR with conventional stent-graft devices. Differences in demographics, aneurysm morphology, and outcomes between candidates and noncandidates undergoing open repair suggest that differential risks apply to ruptured aneurysm patients. Protocols and future reports of EVAR for rAAAs should be tailored to these results. Device and technique modifications are necessary to increase the applicability of EVAR for rAAAs.