Epicardial deletion of Sox9 leads to myxomatous valve degeneration and identifies Cd109 as a novel gene associated with valve development.

Epicardial-derived cells (EPDCs) are involved in the regulation of myocardial growth and coronary vascularization and are critically important for proper development of the atrioventricular (AV) valves. SOX9 is a transcription factor expressed in a variety of epithelial and mesenchymal cells in the developing heart, including EPDCs. To determine the role of SOX9 in epicardial development, an epicardial-specific Sox9 knockout mouse model was generated. Deleting Sox9 from the epicardial cell lineage impairs the ability of EPDCs to invade both the ventricular myocardium and the developing AV valves. After birth, the mitral valves of these mice become myxomatous with associated abnormalities in extracellular matrix organization. This phenotype is reminiscent of that seen in humans with myxomatous mitral valve disease (MVD). An RNA-seq analysis was conducted in an effort to identify genes associated with this myxomatous degeneration. From this experiment, Cd109 was identified as a gene associated with myxomatous valve pathogenesis in this model. Cd109 has never been described in the context of heart development or valve disease. This study highlights the importance of SOX9 in the regulation of epicardial cell invasion-emphasizing the importance of EPDCs in regulating AV valve development and homeostasis-and reports a novel expression profile of Cd109, a gene with previously unknown relevance in heart development.

The anti-proliferative effects of a frankincense extract in a window of opportunity phase ia clinical trial for patients with breast cancer.

PURPOSE: Boswellic acids, active components of frankincense, suppress tumor proliferation in vitro with a strong clinical trial safety profile in patients with inflammatory diseases. We performed a Phase Ia window of opportunity trial of Boswellia serrata (B. serrata) in patients with breast cancer to evaluate its biologic activity and safety. METHODS: Patients with invasive breast cancer were treated pre-operatively with B. Serrata (2400 mg/day PO) until the night before surgery for a median of 11 days (SD 6 days; range: 5-23 days). Paraffin-embedded sections from pretreatment diagnostic core biopsies and post-treatment surgical excisions were evaluated using a tunnel assay and immunohistochemistry staining with Ki-67 antibodies. A non-intervention retrospective control arm consisting of core and surgical tissue specimens from untreated patients was used to compare patients treated with B. Serrata. The change in proliferation and apoptosis between diagnostic core specimens and surgical specimens was compared between the control and treatment groups using a two-tailed paired t-test. RESULTS: Twenty-two patients were enrolled, of which 20 received treatment, and 18 had sufficient tissue for IHC. There was an increase in percent change in proliferation from core biopsy to surgical excision in the control group (n = 18) of 54.6 ± 21.4%. In the B. serrata-treated group there was a reduction in proliferation between core biopsy and excision (n = 18) of 13.8 ± 11.7%. This difference was statistically significant between the control and B. serrata-treated groups (p = 0.008). There was no difference in change in apoptosis. There were no serious adverse events related to the drug. CONCLUSION: Boswellia serrata inhibited breast cancer proliferation and was well-tolerated in a Phase Ia window of opportunity trial.

Racial Disparities in Breast Cancer Genetic Testing May be Mitigated by Counseling.

BACKGROUND: Currently, racial disparities exist in access to genetic testing. Recent developments have helped narrow the gap in accessibility. The purpose of this study was to determine whether racial disparities in genetic consultation attendance and completion of genetic testing persist, and, if so, factors that contribute to under-utilization of these resources. METHODS: A single-institution retrospective review of breast patients referred for genetic counseling between 2017 and 2019 was performed. Univariate and multivariate logistic regression evaluated factors associated with genetic counseling attendance and genetic testing. RESULTS: A total of 596 patients were referred for genetic counseling: 433 (72.7%) white; 138 (23.2%) black; and 25 (4.2%) other or unknown. In multivariate analysis, black patients, patients without breast cancer family history, and patients without a current cancer diagnosis, classified as high risk, were significantly less likely to attend their genetics appointment (p = 0.010, p = 0.007, p = 0.005, respectively). Age, insurance type, distance from facility, and need for chemotherapy did not significantly impact consult completion rate. Of the patients who completed a genetic consult, 84.4% (n = 248) had genetic testing and 17.7% (n = 44) had a pathogenic variant. For patients who attended counseling, there were no significant factors that were predictive with receipt of genetic testing. CONCLUSIONS: In this study, there was a significant association between race and attending genetic counseling. Once counseled, most patients went on to receive genetic testing, and racial disparities in testing disappeared, emphasizing the value of providing additional education about the importance and purpose of genetic testing.

Benefits of early vascular provider involvement in wound care center management of patients with underlying arterial disease.

OBJECTIVES: Peripheral arterial disease (PAD) can reduce wound healing rates by ≤30%. Current literature suggests wound outcomes are improved when management is driven by vascular providers. However, whether this benefit is derived solely from early vascular provider involvement remains unclear. METHODS: A retrospective analysis was performed of 80 limbs with chronic wounds and underlying PAD seen at our institution's wound center between July 2022 and July 2023. Arterial disease was defined by the following criteria: (1) prior PAD diagnosis, (2) ankle-brachial-index of <0.9 or toe pressure of <70 mm Hg, or (3) absent peripheral pulses. Patients were divided into early (<6 week) vascular provider exposure (EVE; n = 45) or late/no vascular exposure (LNVE; n = 35). Providers included vascular surgeons and affiliated advanced practitioners. The primary outcome studied was overall time to wound healing. Statistical analysis included χ2 tests, t test, Pearson correlation, Kaplan-Meier analysis, and Cox regression modeling (variables included in a multivariate model if univariate effect on healing was associated at P < .1). RESULTS: Baseline demographic profiles were similar between groups with exception of lower baseline albumin (P = .037), more heart failure (P = .013), and more prior peripheral endovascular interventions (P = .013) in the EVE group. Although the initial wound locations and sizes were similar, EVE wounds had significantly higher WIfI wound scores (1.9 ± 0.1 vs 1.6 ± 0.1; P = .039). Although more LNVE patients developed radiographic osteomyelitis (31.8% vs 55.6%; P = .033), fewer underwent operative debridement or amputation (100% vs 63.2%; P = .008). On univariate analysis, healing time tended to be shorter in EVE, but not significantly (P = .089). When controlled for comorbidities, however, healing rates were nearly two-fold higher in EVE (hazard ratio, 2.42; 95% confidence interval, 1.21-4.84). LNVE wounds also took significantly longer to reach checkpoints including time to >75% granulation (P = .05), 15% weekly size decrease (P = .044), and epithelialization (P = .026). LNVE patients required more wound center visits (P = .024) and procedures (P = .005) with a longer time to intervention (P = .041). All EVE patients obtained ankle-brachial indices, with 90.9% of them available at their first wound care visit (P < .001). Although a slightly greater proportion of patients underwent a major amputation in EVE (15.6% vs 11.4%; P = .595), this difference did not attain significance; additionally, 100% of EVE patients had documented discussion of nonsalvageable limbs before amputation. CONCLUSIONS: Early exposure to vascular practitioners improves wound healing time, timeliness to intervention, and wound center and hospital resource use in patients with PAD. Further investigation into benefits of vascular involvement within community wound center models could significantly improve awareness and accessibility of arterial wound care in smaller/remote communities.

Defining Pathologic Upstaging in cT1b Esophageal Cancer: Should We Consider Neoadjuvant Therapy?

INTRODUCTION: Neoadjuvant chemoradiation therapy (NCRT) for cT1b esophageal cancer is not recommended despite the risk of pathologic upstaging with increased depth of penetration. We aimed to (1) define the rate of and factors associated with pathologic upstaging, (2) describe current trends in treatments, and (3) compare overall survival (OS) with and without NCRT for surgically resected cT1b lesions. METHODS: We used the 2020 National Cancer Database to identify patients with cT1b N0 esophageal cancer with or without pathologic upstaging who underwent removal of their tumor. We built multivariable logistic regression models to assess factors associated with pathologic upstaging. Survival was compared using log-rank analysis and modeled using multivariable Cox proportional hazards regressions. RESULTS: Out of 1106 patients with cT1b esophageal cancer, 17.3% (N = 191) had pathologic upstaging. A higher tumor grade (P = 0.002), greater tumor size (P < 0.001), and presence of lympho-vascular invasion (P < 0.001) were associated with pathologic upstaging. 8.0% (N = 114) of patients were treated with NCRT. Five-y OS was 49.4% for patients who received NCRT compared to 67.2% for upfront esophagectomy (P < 0.05). Pathologic upstaging was associated with decreased OS (pathologic upstaging 43.7% versus no pathologic upstaging 67.7%) (hazard ratio 2.12 [95% confidence interval, 1.70-2.65; P < 0.001]). Compared to esophagectomy, endoscopic local tumor excision was associated with a decreased OS (hazard ratio 1.50 [95% confidence interval, 1.19-1.89; P = 0.001]). CONCLUSIONS: Pathologic upstaging of cT1b lesions is associated with decreased OS. Esophagectomy is associated with a survival benefit over endoscopic local tumor excision for these lesions. NCRT is not associated with an increase in OS in cT1b lesions compared to upfront esophagectomy.

Letter of Recommendation Characteristics Associated with Interview Offer to a Vascular Surgery Residency Program.

BACKGROUND: Letters of recommendation (LOR) are considered by program directors (PDs) to be an integral part of the residency application. With the conversion of United States Medical Licensing Examination (USMLE) Step 1 to a binary pass/fail outcome, LORs will likely have higher important in the application process moving forward. However, their utility in securing an interview for a particular applicant remains undetermined. This study aims to identify the applicant and LOR characteristics associated with an interview invitation. METHODS: Letter writer (n = 977) characteristics were abstracted from applications (n = 264) to an individual integrated vascular surgery residency program over 2 application cycles. A validated text analysis program, Linguistic Inquiry and Word Count, was used to characterize LOR content. Applicant, letter writer, and LOR characteristics associated with an interview invitation were determined using multivariable analysis. RESULTS: Letter writers were 70.9% vascular surgeons (VS), 23.7% PDs, and 45.4% professors. Applicants offered an interview were more likely to come from a top 50 medical school (35.2% vs 25.8%, P = 0.013) and an institution with a home vascular program (45.5% vs 34.1%, P = 0.006). Alpha Omega Alpha membership was significantly associated with interview offer (28.4%, P < 0.001). A greater proportion of letters from VS was associated with an interview offer (P < 0.001) compared with letter writers of other specialties. One or more PD letters were significantly associated with an interview offer (79.55% vs 20.45%, P = 0.008), whereas number of letters from APDs was not significantly associated with interview offer. Letters written by away institution faculty were significantly associated with interview offer (75%, P < 0.001), whereas nonclinical letters were not. Presence of one or more letters from a chair (57.95% vs 42.05%, P = 0.015) or chief (67.05% vs 32.95%, P = 0.028) was significantly associated with interview offer. Letters for applicants offered an interview had more references to research and teaching, which were more common in letters written by versus Letters written by PDs were more likely to use assertive, advertising language in favor of applicants. There were no significant applicant, letter writer, or LOR characteristics associated with a top 20 rank. CONCLUSIONS: Successful applicants were more likely to have LORs written by VS, PDs, and those of higher academic rank with references to research and teaching.

The prevalent I686T human variant and loss-of-function mutations in the cardiomyocyte-specific kinase gene TNNI3K cause adverse contractility and concentric remodeling in mice.

TNNI3K expression worsens disease progression in several mouse heart pathology models. TNNI3K expression also reduces the number of diploid cardiomyocytes, which may be detrimental to adult heart regeneration. However, the gene is evolutionarily conserved, suggesting a beneficial function that has remained obscure. Here, we show that C57BL/6J-inbred Tnni3k mutant mice develop concentric remodeling, characterized by ventricular wall thickening and substantial reduction of cardiomyocyte aspect ratio. This pathology occurs in mice carrying a Tnni3k null allele, a K489R point mutation rendering the protein kinase-dead, or an allele corresponding to human I686T, the most common human non-synonymous TNNI3K variant, which is hypomorphic for kinase activity. Mutant mice develop these conditions in the absence of fibrosis or hypertension, implying a primary cardiomyocyte etiology. In culture, mutant cardiomyocytes were impaired in contractility and calcium dynamics and in protein kinase A signaling in response to isoproterenol, indicating diminished contractile reserve. These results demonstrate a beneficial function of TNNI3K in the adult heart that might explain its evolutionary conservation and imply that human TNNI3K variants, in particular the widespread I686T allele, may convey elevated risk for altered heart geometry and hypertrophy.

The impact of nurse navigation on timeliness to treatment for benign high-risk breast pathology.

PURPOSE: High-risk breast pathology is a breast cancer risk factor for which timely treatment is crucial. Nurse navigation programs have been implemented to minimize delays in patient care. This study evaluated nurse navigation in terms of timeliness to surgery for patients with high-risk breast pathology. METHODS: This was a single-institution, retrospective review of patients with identified high-risk breast pathology undergoing lumpectomy between January 2017 and June 2019. Patients were stratified into cohorts based on periods with and without nurse navigation. Preoperative and postoperative time to care as well as demographic and tumor characteristics were compared using univariate and multivariate analysis. RESULTS: 100 patients had assigned nurse navigators and 29 patients did not. Nurse navigation was associated with reduced time from referral to date of surgery (DOS) by 16.9 days (p = 0.003). Patients > 75 years had a shorter time to first appointment (p = 0.03), and patients with Medicare insurance had a reduced time from referral to DOS (p = 0.005). 20% of all patients were upstaged to cancer on final surgical pathology. CONCLUSION: Nurse navigation was significantly associated with decreased time to care for patients with high-risk breast pathology undergoing lumpectomy. We recommend nurse navigation programs as part of a comprehensive approach for patients with high-risk breast pathology.

Step 1 is Pass/Fail, Now What? Can Clinical Clerkship Grades be Used as a Reliable Metric to Screen General Surgery Residency Applicants?

INTRODUCTION: For decades, the three-digit United States Medical Licensing Exam Step 1 score has been used to competitively evaluate and compare candidates during the residency application process. Starting in 2022, however, all Step 1 scores will be converted to pass/fail. A different quantitative measure will likely gain importance in its stead, one such being clerkship performance grades. This study aims to determine the consistency of class rank and distribution of clerkship grades reported by medical schools for applicants to a general surgery program. METHODS: Candidates' Medical Student Performance Evaluation letters from 141 unique US allopathic medical schools were reviewed for student overall class rank, the number of grading tiers in each clerkship, and the percent achieving honors criteria in each clerkship from the 2020 application cycle. Comparative analysis was performed by region and medical school prestige. RESULTS: Most medical schools rank students using a four-tier system (e.g., fail, pass, high pass, and honors). A third of schools do not provide an overall class rank of students (34.7% of schools); this was most prevalent in the Northeast and Western regions. Schools in the Central US more often rank their students in five tiers compared to the South (P < 0.01). The percent of students that achieve the highest grading tier varies across the core clerkships (mean 37.1%, range 6.5%-78%); an average of 34.5% of students meet the highest honors tier in their Surgery clerkship. Students at US News and World Report Top 20 medical schools are more likely to receive the highest honors tier, across all core clerkships and overall class rank, than students at schools outside the Top 20 (P < 0.05). CONCLUSIONS: In the absence of the United States Medical Licensing Exam Step 1 score, the variability in clerkship grading tiers and overall class rank will likely pose a challenge to residency programs' ability to stratify desirable applicants. Further transparency and standardization may be required to compare students objectively and fairly from medical schools across the country.

Distal Pancreatectomy for Pancreatitis in the Modern Era.

INTRODUCTION: Distal pancreatectomy has not been well examined in the modern era to guide management for pancreatitis. We evaluated this heterogeneous group and the preoperative factors associated with clinically relevant postoperative pancreatic fistula (CR-POPF). METHODS: Patients undergoing distal pancreatectomy at a single academic institution from August 2012 to January 2020 were evaluated. Univariate and multivariate logistic regressions were conducted between preoperative factors and CR-POPF. RESULTS: One hundred and thirty patients underwent distal pancreatectomy. Indication for operative management included chronic pancreatitis and/or pseudotumor in 24.6% (n = 32), disconnected left pancreatic remnant in 31.5% (n = 41), chronic distal pseudocyst in 20.8% (n = 27), and distal necrosis in 13.8% (n = 18). Significant complications (Clavien-Dindo grade ≥ III) were seen in 34% of patients. After surgery, 34.2% developed diabetes, 40% had persistent opioid use, and 22.3% had CR-POPF. In multivariate analysis, male sex was significantly associated with CR-POPF (odds ratio 3.1, P = 0.037), and having a preoperative, therapeutic endoscopic retrograde cholangiopancreatography was protective (odds ratio 0.28, P = 0.020). CONCLUSIONS: Distal pancreatectomy is undertaken in pancreatitis with high morbidity. Female sex and preoperative, therapeutic endoscopic retrograde cholangiopancreatography were significant protective factors for CR-POPF. The natural history of this approach is relevant for those with distal pancreatitis failing medical management.

Staging Endovascular Thoracic and Thoracoabdominal Aortic Aneurysm Repairs and the Risk of Post-operative Spinal Cord Ischemia.

OBJECTIVE: Staged aortic aneurysm repair is one method used to decrease the risk of spinal cord ischemia (SCI) following endovascular aortic intervention. Sequential sacrifice of arteries perfusing the spine may allow for improved spinal perfusion through the development of collateral networks over time. To evaluate the impact of staging endovascular aortic aneurysm repairs on SCI, we conducted a conservative analysis of Vascular Quality Initiative (VQI) data. METHODS: De-identified VQI data were queried for cases of endovascular thoracic and thoracoabdominal aneurysm repairs from year 2014 to 2019. Cases were selected based on inclusion criteria: aneurysmal disease, no ruptures, no prior aortic surgeries, no retreatments, and only cases with complete data on aortic zones and SCI. Chi-square, Student's t-tests, and Mann-Whitney U tests were used for univariable analyses, as appropriate. Logistic regression analyses were used to identify independent predictors of outcome. RESULTS: There were 116 staged aortic repairs (SARs) (8.2%) performed out of a total of 1421 endovascular aortic repairs that fit study criteria. The overall rate of SCI within the study cohort was 3.4% (n = 48). The distribution of SARs and SCI events according to aortic zone coverage are displayed in Table 1. Patients who underwent staged endovascular aortic repairs had higher rates of SCI, pre-op spinal drain placement, non-African-American race, COPD, smoking history, positive stress tests, aspirin and statin use, increased estimated blood loss, physician-modified endografts, number of aortic zones covered, lower pre-op hemoglobin levels, larger aneurysm sac size, fusiform aneurysms, and longer total procedure times, Table 2. After adjusting for factors associated with SCI, a priori, and factors with a P < 0.1 univariable analysis, SAR was not associated with SCI (odds ratio [OR] = 1.86, 95% confidence interval [CI] = 0.77-4.50, P = 0.17). Of the six factors associated with SCI on univariable analysis, only procedure time ≥6 hours (OR = 2.49, 95% CI = 1.09-5.70, P = 0.031) and the number of aortic zones covered (OR = 1.15, 95% CI = 1.00-1.32, P = 0.047) were predictive of SCI. Staged repairs had a lower proportion of permanent SCI (38%, 3 of 8 cases) compared with repairs that were not staged (68%, 27 of 40 cases), with a relative risk reduction of 44% for those who developed SCI, P = 0.21. CONCLUSIONS: In a large national data set, SARs were performed for patients with more extensive aortic disease. SARs were only performed in about 8% of cases and the rate of SCI remained low. After adjusting for baseline comorbidities, extent of aortic disease, and other factors that may potentiate SCI, staged aortic aneurysm repair had a similar risk of SCI compared with non-staged repairs. However, there was a trend toward decreased permanent SCI risk in the SAR group.

Complication accrual impacts pediatric extracorporeal life support mortality.

INTRODUCTION: This study tested the hypothesis that complication accrual during pediatric extracorporeal life support (ECLS) increases mortality irrespective of indication for support. METHODS: Prospectively collected Extracorporeal Life Support Organization (ELSO) registry data for all neonatal and pediatric patients cannulated for ECLS at our institution from 1/1/2015 to 12/31/2020 was stratified based on the presence or absence of complications. We excluded renal replacement therapy from complications, as this is frequently and empirically applied within our practice. RESULTS: Of 114 patients, overall survival to discharge was 66%. 62 patients (54%) had 149 total complications: 29% were mechanical (circuit related), and the rest were patient related. Age (neonatal versus pediatric), sex, race/ethnicity, support type, presence of pre-ECLS arrest, pre-ECLS pH and intubation-to-ECLS duration were not significantly associated with the development of complications. Patients with complications required longer ECLS duration (168 versus 86 median hours, p < 0.001) and were more likely to be decannulated due to death or poor prognosis (25% versus 8%, p = 0.022). One or more ECLS complications was associated with significantly decreased survival by Cox proportional hazard regression (p = 0.003). CONCLUSION: Complications on ECLS are associated with longer support duration and predict decreased survival independent of pre-ECLS variables, suggesting a multidisciplinary ECLS team target for improved outcomes.

Prognostic factors for residual occult disease in shave margins during partial mastectomy.

PURPOSE: Shave margins have been shown to decrease positive final margins in partial mastectomy. We investigated prognostic factors associated with residual disease in shave margins. METHODS: Patients with invasive breast carcinoma and ductal carcinoma in situ (DCIS) who had circumferential shave margins excised during lumpectomy were abstracted from a retrospective database from 2015 to 2018. We defined residual occult disease (ROD) as either (1) residual disease in a shave margin when the initial lumpectomy specimen had negative margins or (2) residual disease in a shave margin that did not correspond with the positive lumpectomy margin. We identified the frequency of ROD and conducted logistic regression analysis to identify associated prognostic factors. RESULTS: 166 Patients (139 invasive carcinoma, 27 DCIS) were included with median follow-up of 28 months (9-50 months). Residual occult disease existed in 34 (24.5%) with invasive carcinoma and 8 (29.6%) with DCIS. In univariate analyses of the invasive group, invasive lobular carcinoma and a positive initial, non-corresponding lumpectomy margin were predictive of ROD (OR 3.63, p = 0.04, OR 3.48, p = 0.003 respectively). In multivariate analysis, a positive lumpectomy margin remained significant, p = 0.007. No variables were associated with ROD in DCIS. CONCLUSION: Residual occult disease was shown to be a frequent event in this analysis of lumpectomy with circumferential shave margins. Having a positive initial lumpectomy margin was predictive of ROD in a non-corresponding margin. Surgeons should consider not being selective in their shave margins or margin of re-excision if shave margins were not obtained in their initial surgery.

Resident-Driven Wellness Initiatives Improve Resident Wellness and Perception of Work Environment.

BACKGROUND: Resident burnout is associated with increased adverse patient events and increased incidence of resident depression and suicide when compared to the general population. We hypothesized that resident-driven assessment and implementation of wellness measures would allow implementation of desired interventions and facilitate improvement in wellness. METHODS: A wellness intervention team was established to address resident wellness and job satisfaction. A needs assessment to determine desired interventions as well as a three-part anonymous 5-point Likert scale survey was developed and distributed to general surgery residents. Following implementation of three measures, a postintervention survey was administered at 6 and 15 mo to the same cohort. Analysis of variance test was used to evaluate for significant difference between preintervention and postintervention surveys. RESULTS: Three interventions were implemented: two protected weekday personal days per year, modernization of resident workspace, and additional meal funds. There were statistically significant changes in perceptions of wellness opportunities (3.14 versus 3.88 and 3.7; P < 0.05), time for wellness (2.53 versus 3.42 and 3.2; P < 0.05), work/life balance satisfaction (2.86 versus 3.71 and 3.41; P < 0.05), and improved quality of life (2.67 versus 3.3 and 3.0; P < 0.05) in both 6-mo and 15-mo postintervention responses. CONCLUSIONS: Implementation of resident-selected wellness measures was found to influence overall resident satisfaction and improved perception of the working environment. Several scores of wellness items showed sustained improvement at 15 mo. These results suggest that resident-driven wellness interventions can positively affect working conditions for residents.

Defects in the Exocyst-Cilia Machinery Cause Bicuspid Aortic Valve Disease and Aortic Stenosis.

BACKGROUND: Bicuspid aortic valve (BAV) disease is a congenital defect that affects 0.5% to 1.2% of the population and is associated with comorbidities including ascending aortic dilation and calcific aortic valve stenosis. To date, although a few causal genes have been identified, the genetic basis for the vast majority of BAV cases remains unknown, likely pointing to complex genetic heterogeneity underlying this phenotype. Identifying genetic pathways versus individual gene variants may provide an avenue for uncovering additional BAV causes and consequent comorbidities. METHODS: We performed genome-wide association Discovery and Replication Studies using cohorts of 2131 patients with BAV and 2728 control patients, respectively, which identified primary cilia genes as associated with the BAV phenotype. Genome-wide association study hits were prioritized based on P value and validated through in vivo loss of function and rescue experiments, 3-dimensional immunohistochemistry, histology, and morphometric analyses during aortic valve morphogenesis and in aged animals in multiple species. Consequences of these genetic perturbations on cilia-dependent pathways were analyzed by Western and immunohistochemistry analyses, and assessment of aortic valve and cardiac function were determined by echocardiography. RESULTS: Genome-wide association study hits revealed an association between BAV and genetic variation in human primary cilia. The most associated single-nucleotide polymorphisms were identified in or near genes that are important in regulating ciliogenesis through the exocyst, a shuttling complex that chaperones cilia cargo to the membrane. Genetic dismantling of the exocyst resulted in impaired ciliogenesis, disrupted ciliogenic signaling and a spectrum of cardiac defects in zebrafish, and aortic valve defects including BAV, valvular stenosis, and valvular calcification in murine models. CONCLUSIONS: These data support the exocyst as required for normal ciliogenesis during aortic valve morphogenesis and implicate disruption of ciliogenesis and its downstream pathways as contributory to BAV and associated comorbidities in humans.

Discharge to a Post-Acute Care Facility after Emergent Femoral Artery Repair is Not Protective Against Wound Complications.

BACKGROUND: Access site complication is the most common adverse event after endovascular intervention, and when emergent operative repair of the common femoral artery (CFA) is needed, patient morbidity can be significantly increased. The intent of this project was to identify predictors of wound events after emergent operative repair of the CFA due to an access site complication. It was hypothesized that patients discharged to a facility would benefit from an ongoing relationship with healthcare professionals as evidenced by more consistent follow-up and lower wound complication rates. METHODS: Patients who had a percutaneous CFA access complication and required emergent open CFA repair at an academic medical institution between 2015 and 2018 were included, and the charts were reviewed retrospectively. Primary outcomes included wound complication and outpatient compliance with vascular surgery clinic visit. Dichotomous groups were evaluated by the chi-squared test, and continuous variables were evaluated by Student's t-test. Univariate and multivariate regression analyses were completed to assess risk factors contributing to wound event or failure of clinic follow-up. RESULTS: Forty-four patients were identified with emergent CFA repair due to an access complication between July 2015 and June 2018. Among this population, 33% of patients had wound complications and 27% were discharged to a facility. Among those discharged to a facility, the rate of follow-up to the vascular surgeon's clinic was significantly lower than those discharged to home (40% vs. 85%, P < 0.05), and the incidence of wound complications appeared greater but did not reach statistical significance (50% vs. 27%, P = 0.11). Univariate analysis indicated that kidney disease, albumin <3 g/dL, and current smoking were predictive of wound complication, whereas on multivariate analysis, only kidney disease remained predictive (P < 0.05, odds ratio = 22). The modified frailty index (mFI) was not predictive of wound complications or compliance with follow-up. However, mFI did approach statistical significance when predicting discharge to a facility. CONCLUSIONS: Despite the availability of medical personnel to arrange transportation and provide wound care in post-acute care facilities, patients who were discharged to a facility after CFA injury requiring emergent repair experienced lower compliance with clinic follow-up and may have suffered more wound complications. Strategies to improve compliance with patient follow-up and wound healing in patients sent to post-acute care facilities are warranted.

Elevated Wall Tension Initiates Interleukin-6 Expression and Abdominal Aortic Dilation.

BACKGROUND: Hypertension (HTN) has long been associated with abdominal aortic aneurysm (AAA) development, and these cardiovascular pathologies are biochemically characterized by elevated plasma levels of angiotensin II (AngII) as well as interleukin-6 (IL-6). A biologic relationship between HTN and AAA has not been established, however. Accordingly, the objective of this study was to evaluate whether elevated tension may initiate IL-6 production to accumulate monocyte/macrophages and promote dilation of the abdominal aorta (AA). METHODS: An IL-6 infusion model (4.36 µg/kg/day) was created utilizing an osmotic infusion pump, and after 4 weeks, AA diameter was measured by digital microscopy. The AA was then excised for CD68 immunostaining and flow cytometric analysis with CD11b and F4/80 to identify macrophages. Aortic segments from wild-type mice were suspended on parallel wires in an ex vivo tissue myograph at experimentally derived optimal tension (1.2 g) and in the presence of elevated tension (ET, 1.7 g) for 3 hr, and expression of IL-6 and monocyte chemoattractant protein-1 (MCP-1) was evaluated by quantitative polymerase chain reaction (QPCR). Isolated aortic vascular smooth muscle cells (VSMCs) were subjected to 12% biaxial cyclic stretch or held static (control) for 3 hr (n = 7), and IL-6 and MCP-1 expressions were evaluated by QPCR. RESULTS: Four-week IL-6 infusion resulted in an AA outer diameter that was 72.5 ± 5.6% (P < 0.05) greater than that of control mice, and aortic dilation was accompanied by an accumulation of macrophages in the AA medial layer as defined by an increase in CD68 + staining as well as an increase by flow cytometric quantification of CD11b+/F4/80+ cells. Wild-type AA segments did not respond to ex vivo application of ET but cyclic stretch of isolated VSMCs increased IL-6 (2.03 ± 0.3 fold) and MCP-1 (1.51 ± 0.11 fold) expression compared to static control (P < 0.05). Pretreatment with the selective STAT3 inhibitor WP1066 blunted the response in both cases. Interestingly, AngII did not stimulate expression of IL-6 and MCP-1 above that initiated by tension and again, the response was inhibited by WP1066, supporting an integral role of STAT3 in this pathway. CONCLUSIONS: An IL-6 infusion model can initiate macrophage accumulation as well as aortic dilation, and under conditions of elevated tension, this proinflammatory cytokine can be produced by aortic VSMCs. By activation of STAT3, MCP-1 is expressed to increase media macrophage abundance and create an environment susceptible to dilation. This biomechanical association between HTN and aortic dilation may allow for the identification of novel therapeutic strategies.

Amplitude mediated chimera states with active and inactive oscillators.

The emergence and nature of amplitude mediated chimera states, spatio-temporal patterns of co-existing coherent and incoherent regions, are investigated for a globally coupled system of active and inactive Ginzburg-Landau oscillators. The existence domain of such states is found to shrink and shift in parametric space with the increase in the fraction of inactive oscillators. The role of inactive oscillators is found to be twofold-they get activated to form a separate region of coherent oscillations and, in addition, decrease the common collective frequency of the coherent regions by their presence. The dynamical origin of these effects is delineated through a bifurcation analysis of a reduced model system that is based on a mean field approximation. Our results may have practical implications for the robustness of such states in biological or physical systems where age related deterioration in the functionality of components can occur.

A role for primary cilia in aortic valve development and disease.

BACKGROUND: Bicuspid aortic valve (BAV) disease is the most common congenital heart defect, affecting 0.5-1.2% of the population and causing significant morbidity and mortality. Only a few genes have been identified in pedigrees, and no single gene model explains BAV inheritance, thus supporting a complex genetic network of interacting genes. However, patients with rare syndromic diseases that stem from alterations in the structure and function of primary cilia ("ciliopathies") exhibit BAV as a frequent cardiovascular finding, suggesting primary cilia may factor broadly in disease etiology. RESULTS: Our data are the first to demonstrate that primary cilia are expressed on aortic valve mesenchymal cells during embryonic development and are lost as these cells differentiate into collagen-secreting fibroblastic-like cells. The function of primary cilia was tested by genetically ablating the critical ciliogenic gene Ift88. Loss of Ift88 resulted in abrogation of primary cilia and increased fibrogenic extracellular matrix (ECM) production. Consequentially, stratification of ECM boundaries normally present in the aortic valve were lost and a highly penetrant BAV phenotype was evident at birth. CONCLUSIONS: Our data support cilia as a novel cellular mechanism for restraining ECM production during aortic valve development and broadly implicate these structures in the etiology of BAV disease in humans. Developmental Dynamics 246:625-634, 2017. © 2017 Wiley Periodicals, Inc.

Differential hypertensive protease expression in the thoracic versus abdominal aorta.

BACKGROUND: Hypertension (HTN), which is a major risk factor for cardiovascular morbidity and mortality, can drive pathologic remodeling of the macro- and microcirculation. Patterns of aortic pathology differ, however, suggesting regional heterogeneity of the pressure-sensitive protease systems triggering extracellular matrix remodeling in the thoracic (TA) and abdominal aortas (AA). This study tested the hypothesis that the expression of two major protease systems (matrix metalloproteinases [MMPs] and cathepsins) in the TA and AA would be differentially affected with HTN. METHODS: Normotensive (BPN3) mice at 14-16 weeks of age underwent implantation of osmotic infusion pumps for 28-day angiotensin II (AngII) delivery (1.46 mg/kg/day; BPN3+AngII; n = 8) to induce HTN. The TA and AA were harvested to determine levels of MMP-2, MMP-9, and membrane type 1-MMP, and cathepsins S, K, and L were evaluated in age-matched BPN3 (n = 8) control and BPH2 spontaneously hypertensive mice (non-AngII pathway; n = 7). Blood pressure was monitored via CODA tail cuff plethysmography (Kent Scientific Corporation, Torrington, Conn). Quantitative real-time polymerase chain reaction and immunoblotting/zymography were used to measure MMP and cathepsin messenger RNA expression and protein abundance, respectively. Target protease values were compared within each aortic region via analysis of variance. RESULTS: Following 28 days infusion, the BPN3+AngII mice had a 17% increase in systolic blood pressure, matching that of the BPH2 spontaneously hypertensive mice (both P < .05 vs BPN3). MMP-2 gene expression demonstrated an AngII-dependent increase in the TA (P < .05), but MMP-9 was not altered with HTN. Expression of tissue inhibitor of metalloproteinases-1 was markedly increased in TA of BPN3+AngII mice, but tissue inhibitor of metalloproteinases-2 demonstrated decreased expression in the AA of both hypertensive groups (P < .05). Only cathepsin K responded to AngII-induced HTN with significant elevation in the TA of those mice, but expression of cathepsin L and cystatin C was inhibited in AA of both hypertensive groups (P < .05). Apoptotic markers were not significantly elevated in any experimental group. CONCLUSIONS: By using two different models of HTN, this study has identified pressure-dependent as well as AngII-dependent regional alterations in aortic gene expression of MMPs and cathepsins that may lead to differential remodeling responses in each of the aortic regions. Further studies will delineate mechanisms and may provide targeted therapies to attenuate down-stream aortic pathology based on demonstrated regional heterogeneity.