From the Guidelines
For AAA lab work, I recommend a comprehensive panel including complete blood count (CBC), basic metabolic panel (BMP), lipid profile, and specific tests for abdominal aortic aneurysm evaluation such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) to assess inflammation, as supported by the most recent guidelines 1. When evaluating patients with suspected or confirmed abdominal aortic aneurysm (AAA), it is essential to consider the risk factors and comorbidities that may impact management decisions.
- Key risk factors for AAA include hypertension, smoking history, family history of aneurysms, and age, as highlighted in the 2022 ACC/AHA guideline for the diagnosis and management of aortic disease 1.
- The frequency of lab testing depends on aneurysm size, with small aneurysms (<4cm) typically requiring lab work every 6-12 months, while larger aneurysms may need more frequent monitoring every 3-6 months, as suggested by the ACR Appropriateness Criteria for screening for abdominal aortic aneurysm 1.
- Coagulation studies, including PT/INR and PTT, are necessary if surgical intervention is being considered, and kidney function tests are crucial for patients with vascular disease, as they often have concurrent renal issues, as noted in the ACR Appropriateness Criteria for pulsatile abdominal mass suspected abdominal aortic aneurysm 1.
- Regular monitoring of these values helps evaluate overall health status and identify complications that might influence management decisions for AAA patients, ultimately reducing morbidity, mortality, and improving quality of life, as emphasized by the 2022 ACC/AHA guideline 1.
From the Research
AAA Lab Work
- Abdominal aortic aneurysm (AAA) is a pathologic condition with progressive abdominal aortic dilatation of 3.0 cm or more that predisposes the abdominal aorta to rupture 2.
- The risk factors for abdominal aortic aneurysm include hypertension, coronary artery disease, tobacco use, male sex, a family history of abdominal aortic aneurysm, age older than 65 years, and peripheral artery disease 2, 3.
- Abdominal ultrasonography is the preferred modality to screen for abdominal aortic aneurysm because of its cost-effectiveness and lack of exposure to ionizing radiation 2, 3.
Management and Screening
- The decision to screen for AAAs is challenging, but the United States Preventive Services Task Force recommended that men between the age of 65 to 75 years who have ever smoked should be screened at least once for AAAs by abdominal ultrasonography 2, 3.
- Management options for patients with an asymptomatic AAA include reduction of risk factors such as smoking, hypertension and dyslipidemia; medical therapy with beta-blockers; watchful waiting; endovascular stenting; and surgical repair depending on the size and expansion rate of the aneurysm and underlying comorbidities 3.
- Surgical management, which includes open and endovascular aneurysm repair, is indicated when the aneurysm diameter is 5.5 cm or larger in men and 5.0 cm or larger in women 2.
Pathogenesis and Metabolomics
- Genome-wide association studies have identified novel drug targets, e.g. interleukin-6 blockade, to limit AAA growth and rupture 4.
- Metabolomics analysis has identified abnormal energy, lipid, and amino acid metabolism in abdominal aortic aneurysms, and potential biomarkers that could affect the size of AAAs 5.
- The progression of an AAA may be related to 13 metabolites, including citric acid, 2-oxoglutarate, and arginine, which indicate disordered metabolism of energy, lipids, and amino acids in AAAs 5.