Why selective screening for asymptomatic carotid stenosis is currently appropriate: a special report.

INTRODUCTION: Two of the main reasons recent guidelines do not recommend routine population-wide screening programs for asymptomatic carotid artery stenosis (AsxCS) is that screening could lead to an increase of carotid revascularization procedures and that such mass screening programs may not be cost-effective. Nevertheless, selective screening for AsxCS could have several benefits. This article presents the rationale for such a program. AREAS COVERED: The benefits of selective screening for AsxCS include early recognition of AsxCS allowing timely initiation of preventive measures to reduce future myocardial infarction (MI), stroke, cardiac death and cardiovascular (CV) event rates. EXPERT OPINION: Mass screening programs for AsxCS are neither clinically effective nor cost-effective. Nevertheless, targeted screening of populations at high risk for AsxCS provides an opportunity to identify these individuals earlier rather than later and to initiate a number of lifestyle measures, risk factor modifications, and intensive medical therapy in order to prevent future strokes and CV events. For patients at 'higher risk of stroke' on best medical treatment, a prophylactic carotid intervention may be considered.

Recent advances and controversial issues in the optimal management of asymptomatic carotid stenosis.

OBJECTIVE: The optimal management of patients with asymptomatic carotid stenosis (AsxCS) is enduringly controversial. We updated our 2021 Expert Review and Position Statement, focusing on recent advances in the diagnosis and management of patients with AsxCS. METHODS: A systematic review of the literature was performed up to August 1, 2023, using PubMed/PubMed Central, EMBASE and Scopus. The following keywords were used in various combinations: "asymptomatic carotid stenosis," "carotid endarterectomy" (CEA), "carotid artery stenting" (CAS), and "transcarotid artery revascularization" (TCAR). Areas covered included (i) improvements in best medical treatment (BMT) for patients with AsxCS and declining stroke risk, (ii) technological advances in surgical/endovascular skills/techniques and outcomes, (iii) risk factors, clinical/imaging characteristics and risk prediction models for the identification of high-risk AsxCS patient subgroups, and (iv) the association between cognitive dysfunction and AsxCS. RESULTS: BMT is essential for all patients with AsxCS, regardless of whether they will eventually be offered CEA, CAS, or TCAR. Specific patient subgroups at high risk for stroke despite BMT should be considered for a carotid revascularization procedure. These patients include those with severe (≥80%) AsxCS, transcranial Doppler-detected microemboli, plaque echolucency on Duplex ultrasound examination, silent infarcts on brain computed tomography or magnetic resonance angiography scans, decreased cerebrovascular reserve, increased size of juxtaluminal hypoechoic area, AsxCS progression, carotid plaque ulceration, and intraplaque hemorrhage. Treatment of patients with AsxCS should be individualized, taking into consideration individual patient preferences and needs, clinical and imaging characteristics, and cultural, ethnic, and social factors. Solid evidence supporting or refuting an association between AsxCS and cognitive dysfunction is lacking. CONCLUSIONS: The optimal management of patients with AsxCS should include BMT for all individuals and a prophylactic carotid revascularization procedure (CEA, CAS, or TCAR) for some asymptomatic patient subgroups, additionally taking into consideration individual patient needs and preference, clinical and imaging characteristics, social and cultural factors, and the available stroke risk prediction models. Future studies should investigate the association between AsxCS with cognitive function and the role of carotid revascularization procedures in the progression or reversal of cognitive dysfunction.

Computer Science meets Vascular Surgery: Keeping a pulse on artificial intelligence.

Artificial intelligence (AI)-based technologies have garnered interest across a range of disciplines in the past several years, with an even more recent interest in various health care fields, including Vascular Surgery. AI offers a unique ability to analyze health data more quickly and efficiently than could be done by humans alone and can be used for clinical applications such as diagnosis, risk stratification, and follow-up, as well as patient-used applications to improve both patient and provider experiences, mitigate health care disparities, and individualize treatment. As with all novel technologies, AI is not without its risks and carries with it unique ethical considerations that will need to be addressed before its broad integration into health care systems. AI has the potential to revolutionize the way care is provided to patients, including those requiring vascular care.

Transition From Mentored to Independent NIH Funding by Gender and Department.

This study uses National Institutes of Health RePORTER data for mentored K awards and R01-equivalent grants to all departments in US schools of medicine to characterize K-award distribution and K-to-R transition by gender and department between 1997 and 2021.

Rates of National Institutes of Health Funding for Surgeon-Scientists, 1995-2020.

Importance: Surgeon-scientists are uniquely positioned to facilitate translation between the laboratory and clinical settings to drive innovation in patient care. However, surgeon-scientists face many challenges in pursuing research, such as increasing clinical demands that affect their competitiveness to apply for National Institutes of Health (NIH) funding compared with other scientists. Objective: To examine how NIH funding has been awarded to surgeon-scientists over time. Design, Setting, and Participants: This cross-sectional study used publicly available data from the NIH RePORTER (Research Portfolio Online Reporting Tools Expenditures and Results) database for research project grants awarded to departments of surgery between 1995 and 2020. Surgeon-scientists were defined as NIH-funded faculty holding an MD or MD-PhD degree with board certification in surgery; PhD scientists were NIH-funded faculty holding a PhD degree. Statistical analysis was performed from April 1 to August 31, 2022. Main Outcome: National Institutes of Health funding to surgeon-scientists compared with PhD scientists, as well as NIH funding to surgeon-scientists across surgical subspecialties. Results: Between 1995 and 2020, the number of NIH-funded investigators in surgical departments increased 1.9-fold from 968 to 1874 investigators, corresponding to a 4.0-fold increase in total funding (1995, $214 million; 2020, $861 million). Although the total amount of NIH funding to both surgeon-scientists and PhD scientists increased, the funding gap between surgeon-scientists and PhD scientists increased 2.8-fold from a $73 million difference in 1995 to a $208 million difference in 2020, favoring PhD scientists. National Institutes of Health funding to female surgeon-scientists increased significantly at a rate of 0.53% (95% CI, 0.48%-0.57%) per year from 4.8% of grants awarded to female surgeon-scientists in 1995 to 18.8% in 2020 (P < .001). However, substantial disparity remained, with female surgeon-scientists receiving less than 20% of NIH grants and funding dollars in 2020. In addition, although there was increased NIH funding to neurosurgeons and otolaryngologists, funding to urologists decreased significantly from 14.9% of all grants in 1995 to 7.5% in 2020 (annual percent change, -0.39% [95% CI, -0.47% to -0.30%]; P < .001). Despite surgical diseases making up 30% of the global disease burden, representation of surgeon-scientists among NIH investigators remains less than 2%. Conclusion and Relevance: This study suggests that research performed by surgeon-scientists continues to be underrepresented in the NIH funding portfolio, highlighting a fundamental need to support and fund more surgeon-scientists.

Gender Disparity in National Institutes of Health Funding Among Surgeon-Scientists From 1995 to 2020.

Importance: Surgical diseases account for approximately 30% of the global burden of disease. Gender diversity in biomedical research is critical to generate innovative patient-centered research in surgery. Objective: To examine the distribution of biomedical research funding by the National Institutes of Health (NIH) among women and men surgeon-scientists during a 25-year period. Design, Setting, and Participants: This cross-sectional study used publicly available data from the NIH RePORTER (Research Portfolio Online Reporting Tools: Expenditures and Results) database for research project grants awarded to women and men surgeon-scientists who were principal investigators between 1995 and 2020. Data were retrieved between January 20 and March 20, 2022. The representation of women surgeon-scientists among academic surgeons was compared with the representation of men surgeon-scientists over time. Main Outcomes and Measures: Distribution of NIH funding to women and men surgeon-scientists was examined via 2 metrics: holding a large-dollar (ie, R01-equivalent) grant and being a super principal investigator (SPI) with $750 000 or more in total annual research funding. Statistical analysis was performed between April 1 and August 31, 2022. Results: Between 1995 and 2020, 2078 principal investigator surgeons received funding from the NIH. The proportion of women academic surgeons who were surgeon-scientists remained unchanged during this same period (1995, 14 of 792 [1.8%] vs 2020, 92 of 3834 [2.4%]; P = .10). Compared with their men counterparts, women surgeon-scientists obtained their first NIH grant earlier in their career (mean [SD] years after first faculty appointment, 8.8 [6.2] vs 10.8 [7.9] years; P < .001) and were as likely to obtain large-dollar grants (aRR, 0.99 [95% CI, 0.95-1.03]) during the period 2016 to 2020. Despite this success, women surgeon-scientists remained significantly underrepresented among SPIs and were 25% less likely to be an SPI (aRR, 0.75 [95% CI, 0.60-0.95] during the period 2016 to 2020). Conclusions and Relevance: The findings of this cross-sectional study of NIH-funded surgeons suggest that women surgeons remained underrepresented among surgeon-scientists over a 25-year period despite early career success in receiving NIH funding. This is concerning and warrants further investigation to increase the distribution of NIH funding among women surgeon-scientists.

Association of Demographic Factors and Medical School Experiences With Students' Intention to Pursue a Surgical Specialty and Practice in Underserved Areas.

Importance: The surgical workforce shortage is a threat to promoting health equity in medically underserved areas. Although the Health Resources and Services Administration and the American College of Surgeons have called to increase the surgical pipeline for trainees to mitigate this shortage, the demographic factors associated with students' intention to practice in underserved areas is unknown. Objective: To evaluate the association between students' demographics and medical school experiences with intention to pursue surgery and practice in underserved areas. Design, Setting, and Participants: This cross-sectional study surveyed graduating US allopathic medical students who matriculated between 2007-2008 and 2011-2012. Analysis began June 2020 and ended December 2020. Main Outcomes and Measures: Intention to pursue surgery and practice in underserved areas were retrieved from the Association of American Medical Colleges graduation questionnaire. Logistic regression models were constructed to evaluate (1) the association between demographic factors and medical students' intention to pursue surgical specialties vs medical specialties and (2) the association between demographic factors and medical school electives with intention to practice in underserved areas. Results: Among 57 307 students who completed the graduation questionnaire, 48 096 (83.9%) had complete demographic data and were included in the study cohort. The mean (SD) age at matriculation was 23.4 (2.5) years. Compared with students who reported intent to pursue nonsurgical careers, a lower proportion of students who reported intent to pursue a surgical specialty identified as female (3264 [32.4%] vs 19 731 [51.9%]; χ2 P < .001). Multiracial Black and White students (adjusted odds ratio [aOR], 1.72; 95% CI, 1.11-2.65) were more likely to report an intent for surgery compared with White students. Among students who reported an intention to pursue surgery, Black/African American students (aOR, 3.24; 95% CI, 2.49-4.22), Hispanic students (aOR, 2.00; 95% CI, 1.61-2.47), multiracial Black and White students (aOR, 2.27; 95% CI, 1.03-5.01), and Indian/Pakistani students (aOR, 1.31; 95% CI, 1.02-1.69) were more likely than White students to report an intent to practice in underserved areas. Students who reported participating in community health (aOR, 1.61; 95% CI, 1.42-1.83) or global health (aOR, 1.83; 95% CI, 1.61-2.07) experiences were more likely to report an intention to practice in underserved areas. Conclusions and Relevance: This study suggests that diversifying the surgical training pipeline and incorporating health disparity and community health in undergraduate or graduate medical education may promote students' motivation to practice in underserved areas.

Costs and complications of endovascular inferior vena cava filter retrieval.

OBJECTIVE: Advanced endovascular techniques are frequently used for challenging inferior vena cava (IVC) filter retrieval. However, the costs of IVC filter retrieval have not been studied. This study compares IVC filter retrieval techniques and estimates procedural costs. METHODS: Consecutive IVC filter retrievals performed at a tertiary center between 2009 and 2014 were retrospectively reviewed. Procedures were classified as standard retrieval (SR) if they required only a vascular sheath and a snare device and as advanced endovascular retrieval (AER) if additional endovascular techniques were used for retrieval. Cost data were based on hospital bills for the procedures. Patients' characteristics, filter dwell time, retrieval procedure details, complications, and costs were compared between the groups. All statistical comparisons were performed using SAS 9.3 software. RESULTS: There were 191 IVC filter retrievals (SR, 157; AER, 34) in 183 patients (mean age, 55 years; 51% male). Fifteen filters (7.9%) were placed at an outside hospital. The indications for placement were mostly therapeutic (76% vs 24% for prophylaxis). All IVC filters were retrievable, with Bard Eclipse (Bard Peripheral Vascular, Tempe, Ariz; 34%) and Cook Günther Tulip (Cook Medical, Bloomington, Ind; 24%) the most common. Venous ultrasound examination of the lower extremities of 133 patients (70%) was performed before retrieval, whereas only 5 patients (2.6%) received a computed tomography scan of the abdomen. There was no difference in the mean filter dwell time in the two groups (SR, 147.9 ± 146.1 days; AER, 161.4 ± 91.3 days; P = .49). AERs were more likely to have had prior attempts at retrieval (23.5%) compared with SRs (1.9%; P < .001). The most common AER techniques used were the wire loop and snare sling (47.1%) and the stiff wire displacement (44.1%). Bronchoscopy forceps was used in four cases (11.8%); this was the only off-label device used. AERs were more likely to require more than one venous access site for the retrieval procedure (23.5% vs 0%; P < .001). AERs were significantly more likely to have longer fluoroscopy time (34.4 ± 18.3 vs 8.1 ± 7.9 minutes; P < .001) and longer total procedural time (102.8 ± 59.9 vs 41.1 ± 25.0 minutes; P < .001) compared with SRs. The complication rate was higher with AER (20.6%) than with SR (5.2%; P = .006). Most complications were abnormal radiologic findings that did not require additional intervention. The procedural cost of AER was significantly higher (AER, $14,565 ± $6354; SR, $7644 ± $2810; P < .001) than that of SR. This translated to an average increase in cost of $6921 ± $3544 per retrieval procedure for AER. CONCLUSIONS: Advanced endovascular techniques provide a feasible alternative when standard IVC filter retrieval techniques do not succeed. However, these procedures come with a higher cost and higher rate of complications.

Readmissions after carotid artery revascularization in the Medicare population.

BACKGROUND: In appropriately selected patients with severe carotid stenosis, carotid revascularization reduces ischemic stroke. Prior clinical research has focused on the efficacy and safety of carotid revascularization, but few investigators have considered readmission as a clinically important outcome. OBJECTIVES: The aims of this study were to examine frequency, timing, and diagnoses of 30-day readmission following carotid revascularization; to assess differences in 30-day readmission between patients undergoing carotid endarterectomy (CEA) and carotid artery stenting (CAS); to describe hospital variation in risk-standardized readmission rates (RSRR); and to examine whether hospital variation in the choice of procedure (CEA vs. CAS) is associated with differences in RSRRs. METHODS: We used Medicare fee-for-service administrative claims data to identify acute care hospitalizations for CEA and CAS from 2009 to 2011. We calculated crude 30-day all-cause hospital readmissions following carotid revascularization. To assess differences in readmission after CAS compared with CEA, we used Kaplan-Meier survival curves and fitted mixed-effects logistic regression. We estimated hospital RSRRs using hierarchical generalized logistic regression. We stratified hospitals into 5 groups by their proportional CAS use and compared hospital group median RSRRs. RESULTS: Of 180,059 revascularizations from 2,287 hospitals, CEA and CAS were performed in 81.5% and 18.5% of cases, respectively. The unadjusted 30-day readmission rate following carotid revascularization was 9.6%. Readmission risk after CAS was greater than that after CEA. There was modest hospital-level variation in 30-day RSRRs (median: 9.5%; range 7.5% to 12.5%). Variation in proportional use of CAS was not associated with differences in hospital RSRR (range of median RSRR across hospital groups 9.49% to 9.55%; p = 0.771). CONCLUSIONS: Almost 10% of Medicare patients undergoing carotid revascularization were readmitted within 30 days of discharge. Compared with CEA, CAS was associated with a greater readmission risk. However, hospitals' RSRR did not differ by their proportional CAS use.

The vascular surgeon-scientist: a 15-year report of the Society for Vascular Surgery Foundation/National Heart, Lung, and Blood Institute-mentored Career Development Award Program.

The Society for Vascular Surgery (SVS) Foundation partnered with the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health (NIH) in 1999 to initiate a competitive career development program that provides a financial supplement to surgeon-scientists receiving NIH K08 or K23 career development awards. Because the program has been in existence for 15 years, a review of the program's success has been performed. Between 1999 and 2013, 41 faculty members applied to the SVS Foundation program, and 29 from 21 different institutions were selected as awardees, resulting in a 71% success rate. Three women (10%) were among the 29 awardees. Nine awardees (31%) were supported by prior NIH F32 or T32 training grants. Awardees received their K award at an average of 3.5 years from the start of their faculty position, at the average age of 39.8 years. Thirteen awardees (45%) have subsequently received NIH R01 awards and five (17%) have received Veterans Affairs Merit Awards. Awardees received their first R01 at an average of 5.8 years after the start of their K award at the average age of 45.2 years. The SVS Foundation committed $9,350,000 to the Career Development Award Program. Awardees subsequently secured $45,108,174 in NIH and Veterans Affairs funds, resulting in a 4.8-fold financial return on investment for the SVS Foundation program. Overall, 23 awardees (79%) were promoted from assistant to associate professor in an average of 5.9 years, and 10 (34%) were promoted from associate professor to professor in an average of 5.2 years. Six awardees (21%) hold endowed professorships and four (14%) have secured tenure. Many of the awardees hold positions of leadership, including 12 (41%) as division chief and two (7%) as vice chair within a department of surgery. Eight (28%) awardees have served as president of a regional or national society. Lastly, 47 postdoctoral trainees have been mentored by recipients of the SVS Foundation Career Development Program on training grants or postdoctoral research fellowships. The SVS Foundation Career Development Program has been an effective vehicle to promote the development and independence of vascular surgeon-scientists in the field of academic vascular surgery.

Race as a predictor of morbidity, mortality, and neurologic events after carotid endarterectomy.

OBJECTIVE: Racial disparities in the outcomes of patients undergoing carotid endarterectomy (CEA) have been reported. We sought to examine the contemporary relationship between race and outcomes and to report postdischarge events after CEA. METHODS: The American College of Surgeons National Surgical Quality Improvement Program Participant Use Data Files were reviewed to identify all CEAs performed from 2005 to 2010 by vascular surgeons. The influence of race on outcomes was examined. Multivariate analysis was performed using variables found to be significant on bivariate analysis. The primary outcomes were stroke and mortality. Secondary outcomes were other 30-day complications, including postdischarge events. RESULTS: CEA was performed on 29,114 white patients (95.7%) and on 1316 black patients (4.3%); the overall stroke and mortality rates were 1.65% and 0.7%, respectively. The stroke rate was 1.6% for whites and 2.5% blacks (P = .009). The 30-day mortality rate was 0.7% for whites and 1.4% for blacks (P = .002). There was a longer operating time (P < .001) and total length of stay (P < .001), more postoperative pneumonias (P = .049), unplanned intubations (P < .001), ventilator dependence (P < .001), cardiac arrests (P < .001), bleeding requiring transfusions (P = .024), and reoperations within 30 days (P = .021) among black patients. Multivariate logistic regression modeling identified black race as an independent risk factor for 30-day mortality (odds ratio, 1.9; P = .007). Black patients also had a greater proportion of in-hospital deaths than white patients (73.7% vs 43.1%; P = .01). There was no between-group difference in the rate of postdischarge strokes. Thirty-six percent of all strokes occurred after discharge at a mean of 8.3 days, and 54.3% of deaths occurred after discharge at a mean of 11 days. CONCLUSIONS: Black race is an independent risk factor for 30-day mortality after CEA. A significant proportion of strokes and deaths occur after discharge in both racial groups evaluated.

Success of carotid endarterectomy in veterans: high medical risk does not equate with high surgical risk.

BACKGROUND: The safety and efficacy of carotid endarterectomy (CEA) in stroke prevention has been well documented. But "high-risk" patients have traditionally been excluded from these studies and may be offered alternate therapies. We examined the safety of CEA in veterans, a medically high-risk group with multiple comorbidities. STUDY DESIGN: The records of all patients having CEAs performed between 1995 and 1999 in the Connecticut Veterans Affairs (VA) hospital were reviewed. Survival and freedom from stroke were determined using Kaplan-Meier survival analysis. The effects of risk factors on outcomes were analyzed with Cox regression. RESULTS: There were 128 CEAs performed in 120 patients, with a mean followup of 8.5 years. Most patients were symptomatic preoperatively and had a high incidence of hypertension (83%), coronary artery disease (64%), diabetes (37%), and pulmonary disease (22%). Incidences of perioperative (30-day) mortality (0.8%), stroke (1.6%), and myocardial infarction (0.8%) were low. Survival rates at 8.9 and 12 years were 50% and 13%, respectively, with 90% patient followup. Freedom from ipsilateral stroke was 90% at 12 years. Age (hazards ratio [HR] 1.1, p=0.004), hypertension (HR 2.6, p=0.04), and elevated creatinine (HR 3.7, p=0.001) were significant risk factors for mortality. Age (HR 0.8, p=0.07) and diastolic blood pressure (HR 1.2, p=0.06) were predictive of ipsilateral stroke. CONCLUSIONS: Despite poor health and symptomatic presentation, patients treated with CEA achieved excellent perioperative outcomes and were protected from stroke for the remainder of their lives. Multiple medical comorbidities should not be used as exclusion criteria for CEA.

Preoperative assessment and management to prevent complications during high-risk vascular surgery.

OBJECTIVE: Most patients requiring vascular surgical reconstruction are at high risk for major morbidity and mortality, with certain vascular procedures at particularly high risk for complications. Although numerous comorbid conditions are precisely the risk factors that determine outcome, we review particular factors for each surgery that may be optimized to alter outcome and minimize postoperative complications. DESIGN: Literature review. RESULTS: Certain aspects of care are common to all vascular surgery procedures, including thoracoabdominal aortic aneurysm repair, pararenal and ruptured abdominal aortic aneurysm repair, mesenteric and renal revascularization, and carotid endarterectomy. Some factors that are important include careful preoperative assessment and optimization of cardiac, pulmonary, and renal function and volume status. In addition, the use of experienced teams during and after the procedure, as well as clear and continuous communication between all surgical team members, may improve outcome. Particular attention to procedural details is also crucial to achieving excellent results. CONCLUSIONS: Patients needing vascular surgery often possess management challenges that increase the risk of perioperative complications. Meticulous attention to details during all phases of care, including preoperative optimization as well as intraoperative procedural conduct and communication, helps achieve optimal results and thus minimize the risk of complications.

A contemporary assessment of carotid body tumor surgery.

Carotid body tumor resection remains a surgical challenge traditionally associated with a 15-30% incidence of cranial nerve injury. The authors reviewed their experience with carotid body tumor surgery to determine whether contemporary awareness of carotid body tumors is leading to earlier detection and operation, resulting in a lower incidence of postoperative cranial nerve injury. Twenty-seven carotid body tumors were resected in 25 patients between 1990 and 2000. No patient died and no patient had postoperative baroreflex failure syndrome. There was 1 stroke (4%) in a patient who required ligation of the internal carotid artery. There were 9 cranial nerve injuries (33%), most commonly to the vagus or hypoglossal nerves, which was not significantly different from the rate of cranial nerve injury (44%) in the 9 patients operated upon between 1984 and 1989 (p=0.37, Fisher's exact test). Multivariate analysis demonstrated that tumor size was the only significant factor predicting cranial nerve injury (p=0.045, logistic regression). Since carotid body tumors with large size or higher Shamblin grades had predictably high operative blood loss and rates of postoperative cranial nerve injury, a high index of suspicion and aggressive surgical management may lead to earlier detection and operation on smaller tumors, ultimately reducing the risk of nerve injury. Nevertheless, carotid body tumor surgery appears to be relatively free of mortality and major morbidity in contemporary practice.