Identification and characterization of new candidates for abdominal aortic aneurysm screening in patients outside of current accepted guidelines

Adherence to SVS Abdominal Aortic Aneurysm Guidelines Among Pati ents Detected by AI-Based Algorithm

OBJECTIVES

This study evaluates adherence to the latest Society for Vascular Surgery (SVS) guidelines on imaging surveillance, physician evaluation, and surgical intervention for abdominal aortic aneurysm (AAA).

METHODS

AI-based natural language processing applied retrospectively identified AAA patients from imaging scans at a tertiary care center between January-March 2019 and 2021, excluding the pandemic period. Retrospective chart review assessed demographics, comorbidities, imaging, and follow-up adherence. Statistical significance was set at p<0.05.

RESULTS

Among 479 identified patients, 279 remained in the final cohort following exclusion of deceased patients. Imaging surveillance adherence was 67.7% (189/279), with males comprising 72.5% (137/189) (Figure 1). The mean age for adherent patients was 73.9 (SD ±9.5) vs. 75.2 (SD ±10.8) for non-adherent patients (Table 1). Adherent females were significantly younger than non-adherent females (76.7 vs. 81.1 years; p=0.003) with no significant age difference in adherent males. Adherent patients were more likely to be evaluated by a vascular provider within six months (p<0.001), but aneurysm size did not affect imaging adherence: 3.0-4.0cm (p=0.24), 4.0-5.0cm (p=0.88), >5.0cm (p=0.29). Based on SVS surgical criteria, 18 males (AAA >5.5cm) and 17 females (AAA >5.0cm) qualified for intervention and repair rates increased in 2021. 34 males (20 in 2019 v. 14 in 2021) and 7 females (2021 only) received surgical intervention below the threshold for repair.

CONCLUSIONS

Despite consistent SVS guidelines, adherence remains moderate. AI-based detection and follow-up algorithms may enhance adherence and long-term AAA patient outcomes, however further research is needed to assess the specific impacts of AI.

Trends, risk factors, and outcomes of selective screening for abdominal aortic aneurysms in at-risk patients

OBJECTIVES

For men ages 65 to 75 years without a smoking history and for women ages 65 to 75 years with a smoking history, the United States Preventative Service Task Force recommends that primary care providers (PCPs) use their clinical judgement when offering abdominal aortic aneurysm (AAA) screening. This study describes the trends in screening for these cohorts, identifies factors that may influence screening rates, and compares outcomes between screened and unscreened patients.

METHODS

The TriNetX population database was queried for subjects with routine PCP visit between ages 65 to 75 from 2007 to 2023 to create cohorts of male smokers, male nonsmokers, and female smokers. Prevalence and 1- and 3-year incidences of AAA screening by ultrasound and computed tomography scans/magnetic resonance imaging (CT/MRI) were calculated. Screened and unscreened patients' demographics, diagnoses, and medications were compared. Rates of AAA diagnosis and repair were compared between unmatched screened and unscreened patients.

RESULTS

Screening for all groups peaked in 2023. Male smokers had the highest screening prevalence (21.2%), followed by male nonsmokers (3.1%) and female smokers (0.90%). The 1-year incidence of screening increased for male smokers, peaking at 8.2% in 2021. The 1-year incidence plateaued at 1.9% for male nonsmokers in 2020 and remained between 0.25% and 0.35% for female smokers for the whole observation period. By 2023, 23.6%, 14.3%, and 24.3% of male smokers, male nonsmokers, and female smokers had been screened via CT/MRI, respectively, with CT/MRI comprising the majority of screening events for all three cohorts. Hyperlipidemia and statin use were associated with screening for all groups (P < .05), whereas a personal history of coronary artery disease was associated with no screening. Screening for male nonsmokers was associated with hypertension, diabetes, and chronic pulmonary obstructive disease (P < .05). Screening in female smokers was associated with family history of coronary artery disease (odds ratio, 1.50; P < .001). For all groups, screening was associated with unruptured AAA diagnosis and endovascular aortic repair (P < .05). Screened female smokers had similar rates of AAA diagnosis as male nonsmokers (4.58% and 4.37%, respectively).

CONCLUSIONS

AAA screening in all at-risk populations increases diagnosis and treatment of AAA, but the screening rate is low for all groups, even with increasing CT/MRI use. Patients with strong risk factors for AAA are not undergoing screening. Collaboration with PCPs is necessary to increase screening rates and ensure that patients with the most clinically consequential risk factors are managed appropriately.

Systemic exogenous progestins with or without estrogens are associated with decreased rates of venous procedures for varicose veins

OBJECTIVES

Risk factors for varicose veins (VVs) such as female sex, pregnancy, and obesity, are high estrogen states, yet the role of systemic progestins with or without estrogens (SPEs) in VV management is not well characterized. This study investigates how SPE use affects rates of venous procedures for patients with VV.

METHODS

The TriNetX database was queried for subjects with International Classification of Diseases, 10th edition, diagnoses of asymptomatic VV, chronic venous insufficiency, and complicated VV (inflammation or ulceration). Patients were divided into a control cohort with no subsequent SPE use, a progestin-only cohort, and a combined estrogen-progestin (CEP) cohort. Further stratification by VV symptomology and premenopausal status (age <40 years) was also performed. Cohorts were one:one propensity matched on known and theorized risk factors for VV including age, race, prior pregnancy, and body mass index. The outcomes of interest were deep vein thrombosis, pregnancy, stab phlebectomy, endovenous ablation, and sclerotherapy.

RESULTS

Database query yielded 674,838 controls, 7597 CEP patients, and 13,758 progestin-only patients before matching. After propensity matching, compared with controls, the CEP cohort received fewer stab phlebectomies (relative risk [RR], 0.52; 95% confidence interval [CI], 0.42-0.64; P < .001), endovenous ablations (RR, 0.50; 95% CI, 0.43-0.59; P < .001) or any venous interventions (RR, 0.68; 95% CI, 0.61-0.76; P < .001), with no difference in sclerotherapy (P = .12). Similarly, the progestin-only cohort was less likely to receive stab phlebectomy (RR, 0.37; 95% CI, 0.31-0.43; P < .001), endovenous ablation (RR, 0.35; 95% CI, 0.31-0.40; P < .001), sclerotherapy (RR, 0.65; 95% CI, 0.56-0.75; P < .001), and any venous procedure (RR, 0.57; 95% CI, 0.52-0.62; P < .001). Compared with the progestin-only cohort, the CEP cohort had higher rates of sclerotherapy (RR, 1.38; 95% CI, 1.12-1.72; P = .003) and overall venous procedures (RR, 1.16; 95% CI, 1.00-1.34; P = .048). When possible, analysis stratified by symptomatic status and menopausal status revealed similar findings for subcohorts. Finally, the CEP cohort had lower risk of pregnancy than controls during the first 1200 days of observation, but subsequently had greater risk of pregnancy (RR, 1.38; 95% CI, 1.21-1.57; P < .001). Kaplan-Meier analysis showed that the rates of venous intervention were lower throughout the observation period.

CONCLUSIONS

This large, population-based cohort study demonstrated that, despite variable risk of deep vein thrombosis and pregnancy for estrogen-progestin and progestin-only treatment cohorts, both SPE formulations were associated with significantly fewer venous procedures for VVs than controls, with progestin-only cohorts undergoing the fewest procedures. This warrants further investigation into the role of SPE in VV disease progression and the usefulness of systemic progestins as an adjunct therapy for VVs.

Chemokine Receptor 2 Is a Theranostic Biomarker for Abdominal Aortic Aneurysms

Abdominal aortic aneurysm (AAA) is a degenerative vascular disease with a high mortality upon rupture. There is no diagnosis to predict the rupture nor effective medical therapies to prevent rupture. Here we demonstrate that the C-C chemokine receptor type 2 (CCR2) is a theranostic biomarker for AAA. In rat AAA models, we determined the potential of a CCR2-targeted positron emission tomography radiotracer [64Cu]Cu-DOTA-ECL1i predicting AAA rupture. Using a CCR2 inhibitor, we observed the effective prevention of rupture in AAA rat models. In humans, CCR2 positron emission tomography showed intense radiotracer uptake along the AAA wall in patients while little signal was observed in healthy volunteers.

Chemokine Receptor 2 Is A Theranostic Biomarker for Abdominal Aortic Aneurysms

Abdominal aortic aneurysm (AAA) is a degenerative vascular disease impacting aging populations with a high mortality upon rupture. There are no effective medical therapies to prevent AAA expansion and rupture. We previously demonstrated the role of the monocyte chemoattractant protein-1 (MCP-1) / C-C chemokine receptor type 2 (CCR2) axis in rodent AAA pathogenesis via positron emission tomography/computed tomography (PET/CT) using CCR2 targeted radiotracer 64 Cu-DOTA-ECL1i. We have since translated this radiotracer into patients with AAA. CCR2 PET showed intense radiotracer uptake along the AAA wall in patients while little signal was observed in healthy volunteers. AAA tissues collected from individuals scanned with 64 Cu-DOTA-ECL1i and underwent open-repair later demonstrated more abundant CCR2+ cells compared to non-diseased aortas. We then used a CCR2 inhibitor (CCR2i) as targeted therapy in our established male and female rat AAA rupture models. We observed that CCR2i completely prevented AAA rupture in male rats and significantly decreased rupture rate in female AAA rats. PET/CT revealed substantial reduction of 64 Cu-DOTA-ECL1i uptake following CCR2i treatment in both rat models. Characterization of AAA tissues demonstrated decreased expression of CCR2+ cells and improved histopathological features. Taken together, our results indicate the potential of CCR2 as a theranostic biomarker for AAA management.