Does the clopidogrel CYP2C19 genotype assay predict postprocedure stenosis in cerebral aneurysms treated with a flow diverter?

OBJECTIVE: Flow diverters have emerged as a popular modality for treating cerebral aneurysms but require dual antiplatelet therapy (DAPT) after placement. Clopidogrel is a common choice but is a prodrug that some patients may not convert into an active metabolite. The CYP2C19 genotype assay is used to predict activation speed; however, limited data exist showcasing whether this genotype accurately predicts postprocedure complications after flow diversion treatment of cerebral aneurysms. Therefore, the authors sought to characterize whether CYP2C19 genotype correlated with the development of postprocedure intimal hyperplasia (stenosis) after flow diverter placement. METHODS: Medical records were reviewed for patients who underwent flow diverter treatment of cerebral aneurysm at a single academic institution between January 1, 2012, and May 31, 2020. Patient demographics and comorbidities were reviewed alongside CYP2C19 genotype assay, DAPT regimen, and postprocedure angiogram data. Stenosis was defined based on review of angiogram data by two independent physicians. RESULTS: In this review of 120 unique cerebral aneurysms, 102 received DAPT with clopidogrel and 18 received DAPT with an alternative agent. Stenosis was present on 3-month follow-up angiogram for 35/102 (34.3%) aneurysms receiving DAPT with clopidogrel and in 11/18 (61.1%) aneurysms receiving an alternative DAPT regimen (p = 0.031). The CYP2C19 genotype did not correlate with postprocedure stenosis (p = 0.35). CONCLUSIONS: Clopidogrel was a significantly more effective DAPT agent for preventing stenosis when compared to nonclopidogrel DAPT regimens. The clopidogrel CYP2C19 genotype did not predict postprocedure stenosis in this cohort of 120 cerebral aneurysms treated with a flow diverter.

Commentary on Ultrasound Instruction in Undergraduate Medical Education: Perspective from Two Students.

Background: Ultrasound integration in undergraduate medical education (UME) has been a focused endeavor in recent years. According to the American Institute of Ultrasound in Medicine, more than a third of all US medical schools have adopted a focused ultrasound training program for medical students. Medical student perspectives on best practices in ultrasound education are lacking in the literature. Curricula Experiences: Two students' reflections are presented regarding two different didactic approaches, flipped classroom and self-study learning models, to teaching ultrasound in the pre-clinical medical education curriculum. Students present reflections on these didactic approaches to facilitate further improvement in ultrasound education curricula. Discussion: The self-directed learning model enabled students to learn foundational ultrasound exam techniques efficiently in a low-stress environment and subsequently optimized the efficiency of later faculty-led learning events. However, we noted that in both the flipped classroom and self-study learning models of education, the training on basic physical properties of ultrasound, tissue characteristics, and probe manipulation was limited. Conclusion: A self-study learning model ultrasound curricula improves perceived learning efficiency and student confidence, especially when followed by faculty-guided didactics and scanning opportunities. We suggest a framework for ultrasound education curricula that includes components of both formats of ultrasound education alongside faculty-led sessions as an ideal model of ultrasound education. Further, we propose the added benefit of inanimate object scanning to optimize students' knowledge of waveform physics (image acquisition and physical properties of materials) early in the ultrasound education process.

Gender Disparities in Aortoiliac Revascularization in Patients with Aortoiliac Occlusive Disease.

BACKGROUND: Gender disparities have been previously reported in aortic aneurysm and critical limb ischemia outcomes; however, limited info is known about disparities in aortoiliac occlusive disease. We sought to characterize potential disparities in this specific population. MATERIAL AND METHODS: Patients who underwent aortobifemoral bypass and aortic thromboendarterectomy (Current Procedural Terminology codes 35646 and 35331) between 2012 and 2019 were identified in the National Surgical Quality Improvement Program database. A binomial regression model was used to estimate gender differences in 30-day morbidity and mortality. Inverse probability weighting was used to standardize demographic and surgical characteristics. RESULTS: We identified 1,869 patients, of which 39.8% were female and the median age was 61 years. Age, body composition, and other baseline characteristics were overall similar between genders; however, racial data were missing for 26.1% of patients. Females had a higher prevalence of preexisting chronic obstructive pulmonary disease (20.9% vs. 14.7%, prevalence difference 6.1%, P < 0.01), diabetes mellitus (25.4% vs. 19.4%, prevalence difference 6.0%, P < 0.01), and high-risk anatomical features (39.4% vs. 33.7%, prevalence difference 5.8%, P = 0.01). Preprocedural medications included a statin in only 68.2% of patients and antiplatelet agent in 76.7% of patients. Females also had a higher incidence of bleeding events when compared to males (25.2% vs. 17.5%, standardized risk difference 7.2%, P < 0.01), but were less likely to have a prolonged hospitalization greater than 10 days (18.2% vs. 20.9%, standardized risk difference -5.0%, P = 0.01). The 30-day mortality rate was not significantly different between genders (4.7% vs. 3.6%, standardized risk difference 1.2%, P = 0.25). CONCLUSIONS: Female patients treated with aortobifemoral bypass or aortic thromboendarterectomy are more likely to have preexisting chronic obstructive pulmonary disease, diabetes mellitus, and high-risk anatomical features. Regardless of a patient's gender, there is poor adherence to preoperative medical optimization with both statins and antiplatelet agents. Female patients are more likely to have postoperative bleeding complications while males are more likely to have a prolonged hospital stay greater than 10 days. Future work could attempt to further delineate disparities using databases with longer follow-up data and seek to create protocols for reducing these observed disparities.

Creating an Ultrasound Scholarly Concentration Program for Medical Students.

INTRODUCTION: Point of care ultrasound (POCUS) is increasingly prevalent and standardized in undergraduate medical education (UME); however, roughly 25% of United States medical schools lack an ultrasound curriculum. One of the commonly cited barriers to ultrasound training in UME is faculty time resources. Here, we describe an ultrasound scholarly concentration program (SCP) designed to provide medical students with ultrasound opportunities in clinical and scholarly domains, while reducing the need for extensive faculty resources. METHODS: SCPs at the University of North Carolina School of Medicine have 3 requirements: an elective course, a longitudinal portfolio, and a final scholarly project. Thus, the ultrasound SCP was designed to comprise an introductory clinical elective to ultrasound, development of a longitudinal scan portfolio, and a final scholarly project in ultrasound related research or educational innovation. A review of the literature and search of the top 50 US medical schools by US News & World Report was performed to assess the novelty of the ultrasound SCP. RESULTS: To the best of our knowledge, the ultrasound SCP is the first scholarly concentration, track or pathway offered to medical students in the United States. It is the first description of a student designed and student led curriculum focused on providing meaningful ultrasound opportunities to students without necessitating unavailable faculty resources and educational infrastructure. CONCLUSION: A novel ultrasound SCP is described which has clinical aims to expose students to clinical ultrasound as well as scholarly aims to facilitate ultrasound related research and educational innovation. It is designed to enable students to make ultrasound a defining characteristic of their medical school experience. The SCP relies on motivated student involvement and near-peer teaching in a way that is self-sustaining and self-improving.