Acute abdominal aortic occlusion: A 16-year single-center experience

Background: Acute abdominal aortic occlusion (AAO) is a rare vascular emergency associated with high morbidity and mortality. In the present study, we analyzed the clinical management and outcomes for a consecutive patient series during a 16-year period. Methods: We included all patients with an acute AAO and bilateral acute limb ischemia who had been treated between 2004 and 2019. Patients with dissection, aneurysm rupture, or chronic occlusive disease were excluded. The patient characteristics, surgical procedures, and outcomes were extracted retrospectively from a prospective aortic database, electronic patient files, and outpatient examination records. The extent of ischemia was classified according to the TASC II (Inter-Society Consensus for the Management of Peripheral Arterial Disease) section on acute limb ischemia. The primary endpoints were 30-day mortality (safety endpoint) and the combined 6-month amputation and/or death rate (efficacy endpoint). The follow-up outcomes, amputation rates, and 30-day complications were evaluated as secondary endpoints. The patient cohort was divided into four 4-year groups (2004-2007, 2008-2011, 2012-2015, 2016-2019) to assess the outcome changes over time. Statistical analysis included c2 tests and univariate and linear regression analyses. Results: A total of 74 patients (57% male; median age, 64.5 years) with an acute AAO were identified. Arterial thrombosis was the most common etiology (66%). The extent of ischemia was TASC I, IIa, IIb, and III in 7%, 39%, 40%, and 14%, respectively. The patient numbers had increased significantly over time (P=.016). Of the patients, 42% had undergone open transfemoral recanalization (including hybrid procedures), 35% open aortic surgery, 15% extra-anatomic bypass surgery, and 5% (four patients) endovascular therapy alone. The overall 30-day mortality rate was 23%, and the 6-month amputation and/or death rate was 43%. The 30-day mortality rate had declined significantly from 54% for 2004 to 2007 to 10% for 2011 to 2015 (odds ratio [OR], 0.10; 95% confidence interval [CI], 0.001-0.52) and 20% for 2016 to 2019 (OR, 0.21; 95% CI, 0.05-0.90), a statistically nonsignificant trend showing that the relative decline in the use of open aortic procedures was associated with decreased 30-day mortality (P=.06). Univariate analysis indicated that elevated serum lactate on admission (OR, 3.33; 95% CI, 1.06-10.48) and an advanced stage of limb ischemia (OR, 4.33), were strongly associated with an increased 30-day mortality rate. The incidence of severe postoperative systemic complications also indicated a greater incidence of both primary endpoints. The 6-month amputation and/or mortality rates were also affected by the presence of atrial fibrillation (OR, 3.63; 95% CI, 1.34-9.79) and increased patient age (OR, 3.96; 95% CI, 1.49-10.53). Conclusions: Acute AAO remains a life-threatening emergency. Immediate transfemoral open or endovascular techniques should be preferred, if technically possible and proper intraoperative imaging is available.