The fate of patients with large abdominal aortic aneurysms referred for consideration for elective repair.

Background: The premise of the Vascular Services Quality Improvement Programme (VSQIP) in management of patients with asymptomatic large abdominal aortic aneurysms (AAA) is reducing mortality from ruptured AAA in a sustainable way without introducing excessive procedure related mortality. Inevitably a proportion of patients are deemed unfit for elective repair. The aim of this study was to report outcomes of patients who were referred with large asymptomatic AAAs including those turned down for elective repair and identify independent risk factors for being turned down for elective open or endovascular repair of AAA.

Methods: Consecutive patients referred to a regional vascular center with a large AAA (greater than 55 mm) between 1 January 2008 and 31 March 2018 were included. All patients underwent the nationally agreed VSQIP pathway which included preoperative cardio-pulmonary exercise testing and contrast enhanced CT scan of aorta. The decision to repair and the modality of repair were made through a Multi-Disciplinary Team MDT process on each patient. Patients were classified into two groups; those managed non-operatively and those offered elective repair. Survival was assessed using Kaplan-Meier analysis. Factors associated with non-operative management were examined using multivariate analysis.

Results: A total of 876 patients of whom 768 were men and 108 were women with a mean age of 74 years (SD: 7.2) and a diagnosis of a large asymptomatic AAA were assessed. One hundred and seventy-four patients (19.9%) were turned down for elective repair and 702 (80.1%) underwent repair [Open: 244(34.8%), EVAR: 458 (65.2%] with perioperative and 30 day mortality of 1.13% (8 patients). Median duration of follow-up was 1530 days (51 months), (inter quartile range: 1714 days). Patients who underwent repair had significantly higher survival rates compared with those who were turned down (P<0.0001). Risk factors for being turned down for elective AAA included anaerobic threshold <8 mL kg min [OR: (95% CI): 2.27 (1.31-3.92)], (P=0.0005), Age>80 yrs. [OR (95% CI): 1.32 (1.012-1.52], (P=0.0203), complex aneurysm morphology [OR (95% CI): 3.70 (2.82-4.87], (P<0.0001), Female gender: [OR: (95% CI): 2.41 (1.32-3.92)], (P<0.0001) and being classed high or very high risk for open AAA repair OR: (95% CI): 6.48 (4.01-10.49)], (P<0.0001).

Conclusions: A significant cohort of patients with large asymptomatic AAA is turned down for elective AAA repair. These patients appear to have significantly lower survival rates than those who are treated. Information on patients turned down for elective AAA repair should be routinely reported.