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Lekah, Alexander

Mayo Clinic

Mayo Clinic

Citations 3

Prospective Assessment of Changes in Target Vessel Peak Systolic Velocity Measurements After Fenestrated-Branched Endovascular Aortic Repair
Macedo, Thanila A. , Lima, Guilherme Baumgardt Barbosa , Hatz, Heather J., Hesley, Gina K. , Lekah, Alexander, Huang, Ying , Mendes, Bernardo C. , Sulzer, Titia A L , Tenorio, Emanuel R , Baumgardt Barbosa Lima, Guilherme, Hatz, Heather, Tallarita, Tiziano , Huang, Ying , Oderich, Gustavo S , Lima, Guilherme B , Mésnard, Thomas , Tenorio, Emanuel R. , Oderich, Gustavo S.

Journal of Endovascular Therapy | September 28, 2025 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1177/15266028251368250 Get It

Objective: Target vessel stenosis or occlusion is a common indication for secondary intervention after fenestrated-branched endovascular aortic repair requiring long-term imaging surveillance including duplex ultrasound (DUS). This study aimed to describe and compare longitudinal changes in peak systolic velocity (PSV) measurements for renal and mesenteric arteries targeted by directional branches (DBs) or reinforced fenestrations (RFs). Methods: Patients enrolled in a prospective, nonrandomized study (2013-2020) had DUS of celiac axis, superior mesenteric artery, and renal arteries (RAs) obtained preoperatively, at 6 to 8 weeks, 6 months, and annually. Vessels with preprocedural stenosis were excluded. Outcomes were variations in PSV over time for target vessels incorporated by DBs or RFs, differences in balloon-expandable stent-grafts (BESGs) and self-expandable stent-grafts (SESGs), PSV measurements prior to secondary interventions related to vessel stenosis, and a predictive value of PSV for stenosis requiring secondary intervention. Results: A total of 419 patients (292 male, mean age 74 ± 8 years old) were enrolled, with 1,311 target vessels analyzed preoperatively, including 607 mesenteric and 704 RAs. Over a median follow-up of 23 months (interquartile range [IQR], 7-36), PSV measurements decreased in the first 6 to 8 weeks after DB incorporation, remained stable, followed by a nonsignificant increase at 5 years. PSV increased in the first 6 months using RFs with postoperative velocities significantly higher ( P < .05) for RFs compared to DBs. Branched mesenteric vessels stented with BESGs had higher velocities than SESGs ( P < .05). Of the 23 target vessels treated by secondary intervention for stenosis, 19 (83%) had velocities above the thresholds for native, nonstented vessels. Furthermore, in RAs (n = 20) PSV effectively predicted clinically relevant stenosis, AUC was 0.98, with a 231 cm/s threshold offering 84% sensitivity with 100% specificity. Conclusion: Longitudinal follow-up shows that velocity changes vary depending on the type of incorporation, vessel, and bridging stent. For DBs, PSV decreased initially, stabilized, and showed a nonsignificant increase at 5 years. In contrast, PSV increased with RFs and remained higher than DBs. Despite these variations, velocities remained below established thresholds for clinically significant stenosis in nonstented vessels. Criteria for in-stent stenosis may differ, and PSV alone should not be the sole indicator for reintervention. Clinical Impact This study provides new insight into duplex ultrasound (DUS) surveillance after fenestrated and branched endovascular aneurysm repair (FB-EVAR). Peak systolic velocity (PSV) trends differed between fenestrations and branches, and stent type influenced flow dynamics. Importantly, most vessels with secondary interventions had elevated PSVs, but many others exceeded native stenosis thresholds without clinical consequence. Despite these variations, velocities remained below established thresholds for clinically significant stenosis in non-stented vessels. Criteria for in-stent stenosis may differ, and PSV alone should not be the sole indicator for reintervention.The reported PSV measurements served as a benchmark for DUS surveillance following FB-EVAR.
Acute Deep Vein Thrombosis and Association with Popliteal Fossa (Baker's) Cysts in Patients with Lower Extremity Duplex Ultrasound Examination
Vlazny, Danielle T. , Meverden, Ryan A., Daniels, Paul R. , Bartlett, Matthew , Hesley, Gina K. , Macedo, Thanila A. , Lekah, Alexander, Houghton, Damon E. , Wysokiński, Waldemar E.

Blood | November 4, 2020 | Volume: 136 | Issue: Supplement 1 | Pages: 9-10

10.1182/blood-2020-134231 Get It

Background: Popliteal fossa cysts (PFCs aka Baker's cysts) are synovial cysts of the knee joint that can be symptomatic or asymptomatic and incidentally identified on ultrasound. Whether PFCs are associated with deep vein thrombosis (DVT) is unknown. Possible mechanisms for an association include direct compression of the popliteal vein, indirect compression on the popliteal vein with leg flexion, adjacent inflammation of the cyst, or relative immobility due to underlying joint disease itself. Methods: Lower extremity venous Duplex ultrasound radiology reports from the inception of electronic archiving through 11/14/2019 were evaluated across the Mayo Clinic Enterprise (Rochester MN, Jacksonville, FL, Scottsdale AZ, and Mayo Clinic Health System) in patients &gt;18 years of age. Natural language processing (NLP) algorithms were created and validated to identify acute DVT (proximal or distal) and PFCs. A random sample of 1,752 ultrasound reports underwent manual review to calculate the sensitivity and specificity of the NLP algorithm. Cases (ultrasounds with acute DVT) were compared to controls (ultrasound without acute DVT) to examine the frequency of PFCs. IRB approval was obtained and patients lacking Minnesota research authorization were excluded. Results: A total of 332,016 lower extremity venous ultrasounds were performed in 223,035 patients; 156,846 unilateral and 175,170 bilateral lower extremities exams. The mean age at ultrasound was 63.3 (SD 16.5) and 54.7% were female. Ultrasound reports were available for analysis starting in 1992 with a significant increase in the number of ultrasounds performed over the study period across the enterprise (Figure 1). Overall, acute DVT was identified in 24,179 (7.3%) of ultrasounds, and PFCs were identified in 32,427 (9.8%) of ultrasounds. The sensitivity and specificity of the NLP algorithm in the full dataset to identify acute DVT was 86.0% and 97.2%, respectfully. The sensitivity and specificity of the NLP algorithm to identify PFCs was 97.8% and 99.5%, respectively. PFCs were present in 9.3% of ultrasounds with acute DVT and 9.8% of ultrasounds without acute DVT (p=0.007), OR 0.94 (95% CI 0.90-0.98). In a multivariate logistic regression model, after adjusting for age and sex, results remained significant (aOR 0.95, 95% CI 0.91-0.995). Comparing ultrasounds before and after 2010, there was a higher percentage of PFCs and acute DVT reported after 2010 (p&lt;0.001 for both). Sensitivity analyses comparing results before or after 2010, by sex, and only in the first ultrasound performed per person, demonstrated similar results. Conclusions: PFCs are negatively associated with the presence of acute DVT on lower extremity venous Duplex ultrasound. This data does not support PFCs as a contributing or causative factor in the development of lower extremity DVT. Figure 1 Disclosures No relevant conflicts of interest to declare.
Neoplastic zebras of venous thrombosis: Diagnostic challenges in vascular medicine
Cornejo, Alejandro ro Donohue, Lekah, Alexander, Kurklinsky, AK, Donohué-Cornejo, Alejandro

Phlebology: The Journal of Venous Disease | October 9, 2014 | Volume: 30 | Issue: 10 | Pages: 744-748

10.1177/0268355514555210 Get It

Venous thrombosis is a common medical problem. Imaging differentiation of neoplasms and venous clots may prove challenging. We report three cases of “mistaken identities” of venous thrombi and neoplasms on the basis of clinical findings and different imaging modalities: ultrasound, computed tomography, and magnetic resonance imaging. Imaging studies are not always reliable and consideration of clinical features, including pretest probability, is necessary for correct diagnosis. A combination of imaging modalities and biopsies is needed for correct diagnosis in some cases.