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BACKGROUND: The United Network for Organ Sharing (UNOS) started recording data on intellectual disability status in 2008. This study aimed to characterize the long-term outcomes for children with intellectual disabilities (IDs) undergoing lung transplantation. METHODS: All pediatric patients (under 18 years old) undergoing bilateral lung transplantation were identified using the UNOS database. The patients were grouped into the following categories: no cognitive delay, possible cognitive delay, and definite cognitive delay. The primary endpoint was graft survival at 3-year posttransplantation. Multivariate Cox proportional hazards modeling was used to estimate the independent effect of cognitive disability on graft survival. RESULTS: Five hundred four pediatric patients who underwent lung transplantation between March 2008 and December 2022 were retrospectively analyzed. 59 had a definite cognitive delay (12%), 23 had a possible delay (5%), and 421 had no delay (83%). When comparing these three groups, there was no significant difference in 60-day graft survival (p = 0.4), 3-year graft survival (p = 0.6), 3-year graft survival for patients who survived at least 60-day posttransplantation (p = 0.9), distribution of causes of death (p = 0.24), nor distribution treatment of rejection within 1-year posttransplantation (p = 0.06). CONCLUSIONS: Intellectual disability does not impact long-term outcomes after bilateral lung transplantation. Intellectual disability should not be a contraindication to bilateral lung transplantation on the basis of inferior graft survival.
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Supervivencia de Injerto , Discapacidad Intelectual , Trasplante de Pulmón , Modelos de Riesgos Proporcionales , Humanos , Discapacidad Intelectual/complicaciones , Femenino , Masculino , Niño , Estudios Retrospectivos , Adolescente , Preescolar , Resultado del Tratamiento , Lactante , Rechazo de Injerto/epidemiología , Estudios de SeguimientoRESUMEN
BACKGROUND: Several studies have explored factors affecting academic employment in surgical subspecialties; however, vascular surgery has not yet been investigated. We examined which elements of surgical training predict future academic productivity and studied characteristics of NIH-funded vascular surgery attendings. METHODS: With approval from the Association of Program Directors in Vascular Surgery (APDVS), the database of recent vascular surgery fellowship (VSF) and integrated vascular surgery residency (IVSR) graduates was obtained, and public resources (Doximity, Scopus, PubMed, NIH, etc.) were queried for research output during and after training, completion of dedicated research years, individual and program NIH funding, current practice setting, and academic rank. Adjusted multivariate regression analyses were conducted for postgraduate academic productivity. RESULTS: From 2013 to 2017, there were 734 graduates. Six hundred three completed VSF and 131 IVSR; 220 (29%) were female. Academic employment was predicted by MD degree, advanced degree, training at a top NIH-funded program, number publications by end of training, and H-index. Dedicated research time before or during vascular training, advanced degree, or graduating from a top NIH-funded program were predictors of publishing >1 paper/year. Number of publications by end of training and years in practice were predictive of H-index ≥5. VSF versus IVSR pathway did not have an impact on future academic employment, annual publication rate as an attending, or H-index. Characterization of NIH-funded attendings showed that they often completed dedicated research time (72%) and trained at a top NIH-funded program (79%). Mean publications by graduation among this group was 15.82 ± 11.3, and they averaged 4.31 ± 4.2 publications/year as attendings. CONCLUSIONS: Research output during training, advanced degrees, and training at a top NIH-funded program predict an academic vascular surgery career. VSF and IVSR constitute equally valid paths to productive academic careers.
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Investigación Biomédica , Internado y Residencia , Especialidades Quirúrgicas , Humanos , Femenino , Masculino , Resultado del Tratamiento , Especialidades Quirúrgicas/educación , Procedimientos Quirúrgicos Vasculares/educación , Bibliometría , EficienciaRESUMEN
The Ross procedure using the inclusion technique with anticommissural plication (ACP) is associated with excellent valve hemodynamics and favorable leaflet kinematics. The objective was to evaluate individual pulmonary cusp's biomechanics and fluttering by including coronary flow in the Ross procedure using an ex vivo three-dimensional-printed heart simulator. Ten porcine and five human pulmonary autografts were harvested from a meat abattoir and heart transplant patients. Five porcine autografts without reinforcement served as controls. The other autografts were prepared using the inclusion technique with and without ACP (ACP and NACP). Hemodynamic and high-speed videography data were measured using the ex vivo heart simulator. Although porcine autografts showed similar leaflet rapid opening and closing mean velocities, human ACP compared to NACP autografts demonstrated lower leaflet rapid opening mean velocity in the right (p = 0.02) and left coronary cusps (p = 0.003). The porcine and human autograft leaflet rapid opening and closing mean velocities were similar in all three cusps. Porcine autografts showed similar leaflet flutter frequencies in the left (p = 0.3) and noncoronary cusps (p = 0.4), but porcine NACP autografts versus controls demonstrated higher leaflet flutter frequency in the right coronary cusp (p = 0.05). The human NACP versus ACP autografts showed higher flutter frequency in the noncoronary cusp (p = 0.02). The leaflet flutter amplitudes were similar in all three cusps in both porcine and human autografts. The ACP compared to NACP autografts in the Ross procedure was associated with more favorable leaflet kinematics. These results may translate to the improved long-term durability of the pulmonary autografts.
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Prótesis Valvulares Cardíacas , Válvula Pulmonar , Animales , Válvula Aórtica/cirugía , Autoinjertos , Fenómenos Biomecánicos , Hemodinámica , Humanos , Válvula Pulmonar/trasplante , Porcinos , Trasplante AutólogoRESUMEN
We present the development of ligands featuring the unconventional hydrogen bond donor, -CF2H, within a metal's secondary coordination sphere. When metalated with palladium, o-CF2H-functionalized 1,10-phenanthroline provides highly directed H-bonding interactions with Pd-coordinated substrates. Spectroscopic and computational analyses with a series of X-type ligand acceptors (-F, -Cl, -Br, -OR) establish the H-bonding interaction strength for the -CF2H group (â¼3 kcal/mol). The synthesis of Pd0/Ni0 complexes and subsequent coupling (Ni) highlight the unique reductive and base compatibility of the -CF2H hydrogen bond donor group.
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Complejos de Coordinación/química , Hidrocarburos Fluorados/química , Níquel/química , Paladio/química , Complejos de Coordinación/síntesis química , Enlace de Hidrógeno , Ligandos , Estructura MolecularRESUMEN
Leishmaniasis is a vector-borne disease uncommonly encountered in the United States. This case report describes a 54-year-old man presenting with rapidly progressing, pruritic, painful ulcerative lesions after recently immigrating from Venezuela. A punch biopsy confirmed infection with Leishmaniasis braziliensis. He was successfully treated with amphotericin B and miltefosine.
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OBJECTIVE: The limited availability of academic surgery positions has led to increased competition for these jobs. Integrated vascular surgery residency (IVSR) allows for earlier specialization, with some programs providing professional development time (PDT). We hypothesized that IVSR and PDT lead to academic employment and increased research productivity. DESIGN: This is a retrospective study of vascular surgery fellowship (VSF) and IVSR graduates. SETTING: Training, number of publications, H-index, NIH funding, and employment history were collected using institutional websites, Doximity, Scopus, PubMed, and NIH Research Portfolio Reporting. PARTICIPANTS: After a review of the research protocol, the Association of Program Directors in Vascular Surgery (APDVS) provided a list of vascular surgery fellowship (VSF) and IVSR graduates. METHODS: After review of the research protocol, the Association of Program Directors in Vascular Surgery (APDVS) provided a list of vascular surgery fellowship (VSF) and IVSR graduates. Training, number of publications, H-index, NIH funding, and employment history were collected using institutional websites, Doximity, Scopus, PubMed, and NIH Research Portfolio Reporting. RESULTS: From 2013-2017, comparison of IVSR (n=131) to VSF (n=603) graduates showed that IVSR graduates were more likely to be women (38.17% vs 28.19%; pâ¯=â¯0.024), be MD graduates (99.24% vs 93.37%; pâ¯=â¯0.008), attended programs in the northeast (41.98% vs 27.5%; p < 0.001), have advanced degrees (13.74% vs 6.97%; pâ¯=â¯0.01) and graduate from larger programs (median 15 vs 14 faculty; pâ¯=â¯0.013). There was no significant difference in number of publications per trainee by the end of training (median 4 vs 3; P=0.61) or annual trend in average number of publications. After training, there was no significant difference in the type of practice, academic affiliation, practice region, publication number, H-index, NIH funding, level of academic appointment, or leadership positions. From 2013-2019, a comparison of IVSR graduates with (n=32) and without PDT (n=190) demonstrated that those with PDT were more likely to be women (53.13% vs 34.74%; pâ¯=â¯0.038), have advanced degrees (28.12% vs 8.95%; pâ¯=â¯0.002), be at larger programs (median 14 vs 9 faculty; p < 0.001), train at a top 10 NIH funded program (65.62% vs 21.58%; p < 0.001) and publish more by the end of IVSR (median 9 vs 3; p < 0.001). Graduates with PDT were more likely to have academic employment and affiliation, a higher yearly publication rate, and greater H-index. CONCLUSION: IVSR and VSF graduates have comparable academic employment and research productivity. However, PDT during IVSR correlates with an eventual academic career and greater research productivity. This study supports the importance of PDT in developing academic vascular surgeons. It remains necessary to continue both IVSR and VSF training paradigms as healthcare needs of the population are met through both academic and non-academic surgeons.
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Internado y Residencia , Cirujanos , Humanos , Femenino , Estados Unidos , Masculino , Selección de Profesión , Estudios Retrospectivos , Cirujanos/educación , Procedimientos Quirúrgicos Vasculares/educaciónRESUMEN
Purpose: Despite a growing number of women entering medical school, a small proportion of women pursue surgical specialties, including pediatric surgery. This multi-center study assesses gender-based differences in measures of scholarly productivity and distribution of faculty positions. Methods: This is a retrospective web-based study of all pediatric surgeons at twelve large institutions across the United States. Data published by the American Association of Medical Colleges was compiled and analyzed to understand the gender distributions of medical students, general surgery residents, and pediatric surgery fellows. P-values were calculated using two-sided Student's independent t-tests and chi-squared tests. Results: There have been a growing number of women applying into pediatric surgery, but the proportion of women matriculating into these fellowships is not concordant. Women are still underrepresented (28%) amongst the pediatric surgeon workforce. A total of 111 pediatric surgeons were identified for this study, which included 31 women (28%) and 80 males (72%). There was a significant difference in the distribution across academic ranks between genders (p < 0.001). Women had significantly fewer publications per year after residency, fewer total publications, and a lower h-index in comparison to men (p < .001, p = .005, p = .002, respectively). Conclusions: Women are not only underrepresented in pediatric surgery, but there are also significant differences in the distribution of faculty positions and scholarly productivity when comparing men and women. There is a pressing need to improve gender diversity and identify barriers that may prevent women from advancing to leadership positions and achieving professional success.
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BACKGROUND AND AIMS: There are a limited number of pharmacologic therapies for coronary artery disease, and few rodent models of occlusive coronary atherosclerosis and consequent myocardial infarction with which one can rapidly test new therapeutic approaches. Here, we characterize a novel, fertile, and easy-to-use HDL receptor (SR-B1)-based model of atherogenic diet-inducible, fatal coronary atherosclerosis, the SR-B1ΔCT/LDLR KO mouse. Additionally, we test intramyocardial injection of Stromal Cell-Derived Factor-1 alpha (SDF-1α), a potent angiogenic cytokine, as a possible therapy to rescue cardiac function in this mouse. METHODS: SR-B1ΔCT/LDLR KO mice were fed the Paigen diet or standard chow diet, and we determined the effects of the diets on cardiac function, histology, and survival. After two weeks of feeding either the Paigen diet (n = 24) or standard chow diet (n = 20), the mice received an intramyocardial injection of either SDF-1α or phosphate buffered saline (PBS). Cardiac function and angiogenesis were assessed two weeks later. RESULTS: When six-week-old mice were fed the Paigen diet, they began to die as early as 19 days later and 50% had died by 38 days. None of the mice maintained on the standard chow diet died by day 72. Hearts from mice on the Paigen diet showed evidence of cardiomegaly, myocardial infarction, and occlusive coronary artery disease. For the five mice that survived until day 28 that underwent an intramyocardial injection of PBS on day 15, the average ejection fraction (EF) decreased significantly from day 14 (the day before injection, 52.1 ± 4.3%) to day 28 (13 days after the injection, 30.6 ± 6.8%) (paired t-test, n = 5, p = 0.0008). Of the 11 mice fed the Paigen diet and injected with SDF-1α on day 15, 8 (72.7%) survived to day 28. The average EF for these 8 mice increased significantly from 48.2 ± 7.2% on day 14 to63.6 ± 6.9% on day 28 (Paired t-test, n = 8, p = 0.003). CONCLUSIONS: This new mouse model and treatment with the promising angiogenic cytokine SDF-1α may lead to new therapeutic approaches for ischemic heart disease.
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Quimiocina CXCL12 , Enfermedad de la Arteria Coronaria , Modelos Animales de Enfermedad , Ratones Noqueados , Receptores de LDL , Receptores Depuradores de Clase B , Animales , Quimiocina CXCL12/metabolismo , Quimiocina CXCL12/genética , Receptores de LDL/genética , Receptores de LDL/deficiencia , Receptores Depuradores de Clase B/genética , Masculino , Neovascularización Fisiológica/efectos de los fármacos , Ratones Endogámicos C57BL , Dieta Aterogénica , Ratones , Función Ventricular Izquierda , Miocardio/patología , Miocardio/metabolismo , Dieta Alta en GrasaRESUMEN
OBJECTIVE: Combined heart-liver transplantation (CHLT) is a definitive therapy reserved for patients with concomitant heart failure and advanced liver disease. A limited number of centers perform CHLT, and even fewer use the en bloc implantation technique. This study 1) reviews clinical outcomes and immunoprotective effects following CHLT, and 2) describes our institution's experience of over two decades using the en bloc technique. METHODS: All patients who underwent CHLT at our institution between January 2003 and July 2023 were identified. Recipient and donor characteristics, operative details, and clinical outcomes were assessed. Kaplan-Meier analysis was performed to evaluate survival following CHLT. RESULTS: A total of 20 patients underwent CHLT using the en bloc technique at our institution between January 2003 and July 2023. At a median follow-up of 3.8 years for patients who survived the perioperative period (n=18), estimated survival at 1- and 5-years was 94% and 75%, respectively. There was 100% freedom from acute moderate rejection, acute severe rejection, and chronic rejection in all patients. No patients required re-transplantation due to rejection. CONCLUSIONS: CHLT is a definitive therapy reserved for patients with multi-organ dysfunction. At our institution, the en bloc technique is the preferred operative approach, as it minimizes cardiac insult, requires fewer anastomoses, minimizes cold ischemia time, and allows for rapid correction of coagulopathy. Overall survival for this cohort is excellent. Episodes of acute rejection were rarely observed, providing further support that the liver may serve an immunoprotective role in multi-organ transplantation.
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OBJECTIVE: The objective of this study is to evaluate survival for combined heart-lung transplant (HLTx) recipients across 4 decades at a single institution. We aim to summarize our contemporary practice based on more than 271 HLTx procedures over 40 years. METHODS: Data were collected from a departmental database and the United Network for Organ Sharing. Recipients younger than age 18 years, those undergoing redo HLTx, or triple-organ system transplantation were excluded, leaving 271 patients for analysis. The pioneering era was defined by date of transplant between 1981 and 2000 (n = 155), and the modern era between 2001 and 2022 (n = 116). Survival analysis was performed using cardinality matching of populations based on donor and recipient age, donor and recipient sex, ischemic time, and sex matching. RESULTS: Between 1981 and 2022, 271 HLTx were performed at a single institution. Recipients in the modern era were older (age 42 vs 34 y; P < .001) and had shorter waitlist times (78 vs 234 days; P < .001). Allografts from female donors were more common in the modern era (59% vs 39%; P = .002). In the matched survival analysis, 30-day survival (97% vs 84%; P = .005), 1-year survival (89% vs 77%; P = .041), and 10-year survival (53% vs 26%; P = .012) significantly improved in the modern era relative to the pioneering era, respectively. CONCLUSIONS: Long-term survival in HLTx is achievable with institutional experience and may continue to improve in the coming decades. Advances in mechanical circulatory support, improved maintenance immunosuppression, and early recognition and management of acute complications such as primary graft dysfunction and acute rejection have dramatically improved the prognosis for recipients of HLTx in our contemporary institutional experience.
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Trasplante de Corazón-Pulmón , Humanos , Femenino , Trasplante de Corazón-Pulmón/mortalidad , Trasplante de Corazón-Pulmón/efectos adversos , Masculino , Adulto , Persona de Mediana Edad , Factores de Tiempo , Estudios Retrospectivos , Supervivencia de Injerto , Resultado del Tratamiento , Factores de Riesgo , Adulto Joven , Bases de Datos Factuales , Rechazo de Injerto , Listas de Espera/mortalidadRESUMEN
BACKGROUND: Various mitral repair techniques have been described. Though these repair techniques can be highly effective when performed correctly in suitable patients, limited quantitative biomechanical data are available. Validation and thorough biomechanical evaluation of these repair techniques from translational large animal in vivo studies in a standardized, translatable fashion are lacking. We sought to evaluate and validate biomechanical differences among different mitral repair techniques and further optimize repair operations using a large animal mitral valve prolapse model. METHODS: Male Dorset sheep (n=20) had P2 chordae severed to create the mitral valve prolapse model. Fiber Bragg grating force sensors were implanted to measure chordal forces. Ten sheep underwent 3 randomized, paired mitral valve repair operations: neochord repair, nonresectional leaflet remodeling, and triangular resection. The other 10 sheep underwent neochord repair with 2, 4, and 6 neochordae. Data were collected at baseline, mitral valve prolapse, and after each repair. RESULTS: All mitral repair techniques successfully eliminated regurgitation. Compared with mitral valve prolapse (0.54±0.18 N), repair using neochord (0.37±0.20 N; P=0.02) and remodeling techniques (0.30±0.15 N; P=0.001) reduced secondary chordae peak force. Neochord repair further decreased primary chordae peak force (0.21±0.14 N) to baseline levels (0.20±0.17 N; P=0.83), and was associated with lower primary chordae peak force compared with the remodeling (0.34±0.18 N; P=0.02) and triangular resectional techniques (0.36±0.27 N; P=0.03). Specifically, repair using 2 neochordae resulted in higher peak primary chordal forces (0.28±0.21 N) compared with those using 4 (0.22±0.16 N; P=0.02) or 6 neochordae (0.19±0.16 N; P=0.002). No difference in peak primary chordal forces was observed between 4 and 6 neochordae (P=0.05). Peak forces on the neochordae were the lowest using 6 neochordae (0.09±0.11 N) compared with those of 4 neochordae (0.15±0.14 N; P=0.01) and 2 neochordae (0.29±0.18 N; P=0.001). CONCLUSIONS: Significant biomechanical differences were observed underlying different mitral repair techniques in a translational large animal model. Neochord repair was associated with the lowest primary chordae peak force compared to the remodeling and triangular resectional techniques. Additionally, neochord repair using at least 4 neochordae was associated with lower chordal forces on the primary chordae and the neochordae. This study provided key insights about mitral valve repair optimization and may further improve repair durability.
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Implantación de Prótesis de Válvulas Cardíacas , Insuficiencia de la Válvula Mitral , Prolapso de la Válvula Mitral , Humanos , Masculino , Animales , Ovinos , Insuficiencia de la Válvula Mitral/diagnóstico por imagen , Insuficiencia de la Válvula Mitral/cirugía , Prolapso de la Válvula Mitral/diagnóstico por imagen , Prolapso de la Válvula Mitral/cirugía , Válvula Mitral/diagnóstico por imagen , Válvula Mitral/cirugía , Implantación de Prótesis de Válvulas Cardíacas/métodos , Cuerdas Tendinosas/cirugía , Resultado del TratamientoRESUMEN
OBJECTIVE: The inclusion technique was developed to reinforce the pulmonary autograft to prevent dilation after the Ross procedure. Anticommissural plication (ACP), a modification technique, can reduce graft size and create neosinuses. The objective was to evaluate pulmonary valve biomechanics using the inclusion technique in the Ross procedure with and without ACP. METHODS: Seven porcine and 5 human pulmonary autografts were harvested from hearts obtained from a meat abattoir and from heart transplant recipients and donors, respectively. Five additional porcine autografts without reinforcement were used as controls. The Ross procedure was performed using the inclusion technique with a straight polyethylene terephthalate graft. The same specimens were tested both with and without ACP. Hemodynamic parameter data, echocardiography, and high-speed videography were collected via the ex vivo heart simulator. RESULTS: Porcine autograft regurgitation was significantly lower after the use of inclusion technique compared with controls (P < .01). ACP compared with non-ACP in both porcine and human pulmonary autografts was associated with lower leaflet rapid opening velocity (3.9 ± 2.4 cm/sec vs 5.9 ± 2.4 cm/sec; P = .03; 3.5 ± 0.9 cm/sec vs 4.4 ± 1.0 cm/sec; P = .01), rapid closing velocity (1.9 ± 1.6 cm/sec vs 3.1 ± 2.0 cm/sec; P = .01; 1.8 ± 0.7 cm/sec vs 2.2 ± 0.3 cm/sec; P = .13), relative rapid opening force (4.6 ± 3.0 vs 7.7 ± 5.2; P = .03; 3.0 ± 0.6 vs 4.0 ± 2.1; P = .30), and relative rapid closing force (2.5 ± 3.4 vs 5.9 ± 2.3; P = .17; 1.4 ± 1.3 vs 2.3 ± 0.6; P = .25). CONCLUSIONS: The Ross procedure using the inclusion technique demonstrated excellent hemodynamic parameter results. The ACP technique was associated with more favorable leaflet biomechanics. In vivo validation should be performed to allow direct translation to clinical practice.
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Insuficiencia de la Válvula Aórtica , Válvula Pulmonar , Humanos , Animales , Porcinos , Autoinjertos , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Trasplante Autólogo , Válvula Pulmonar/cirugía , Válvula Pulmonar/trasplante , Ecocardiografía , Insuficiencia de la Válvula Aórtica/cirugía , Estudios de SeguimientoRESUMEN
PURPOSE: Rheumatic heart disease is a major cause of mitral valve (MV) dysfunction, particularly in disadvantaged areas and developing countries. There lacks a critical understanding of the disease biomechanics, and as such, the purpose of this study was to generate the first ex vivo porcine model of rheumatic MV disease by simulating the human pathophysiology and hemodynamics. METHODS: Healthy porcine valves were altered with heat treatment, commissural suturing, and cyanoacrylate tissue coating, all of which approximate the pathology of leaflet stiffening and thickening as well as commissural fusion. Hemodynamic data, echocardiography, and high-speed videography were collected in a paired manner for control and model valves (n = 4) in an ex vivo left heart simulator. Valve leaflets were characterized in an Instron tensile testing machine to understand the mechanical changes of the model (n = 18). RESULTS: The model showed significant differences indicative of rheumatic disease: increased regurgitant fractions (p < 0.001), reduced effective orifice areas (p < 0.001), augmented transmitral mean gradients (p < 0.001), and increased leaflet stiffness (p = 0.025). CONCLUSION: This work represents the creation of the first ex vivo model of rheumatic MV disease, bearing close similarity to the human pathophysiology and hemodynamics, and it will be used to extensively study both established and new treatment techniques, benefitting the millions of affected victims.
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Enfermedades de las Válvulas Cardíacas , Insuficiencia de la Válvula Mitral , Cardiopatía Reumática , Humanos , Animales , Porcinos , Válvula Mitral/diagnóstico por imagen , Cardiopatía Reumática/patología , Insuficiencia de la Válvula Mitral/diagnóstico por imagen , Enfermedades de las Válvulas Cardíacas/patología , HemodinámicaRESUMEN
Systolic anterior motion (SAM) of the mitral valve (MV) is a complex pathological phenomenon often occurring as an iatrogenic effect of surgical and transcatheter intervention. While the aortomitral angle has long been linked to SAM, the mechanistic relationship is not well understood. We developed the first ex vivo heart simulator capable of recreating native aortomitral biomechanics, and to generate models of SAM, we performed anterior leaflet augmentation and sequential undersized annuloplasty procedures on porcine aortomitral junctions (n = 6). Hemodynamics and echocardiograms were recorded, and echocardiographic analysis revealed significantly reduced coaptation-septal distances confirming SAM (p = 0.003) and effective manipulation of the aortomitral angle (p < 0.001). Upon increasing the angle in our pathological models, we recorded significant increases (p < 0.05) in both coaptation-septal distance and multiple hemodynamic metrics, such as aortic peak flow and effective orifice area. These results indicate that an increased aortomitral angle is correlated with more efficient hemodynamic performance of the valvular system, presenting a potential, clinically translatable treatment opportunity for reducing the risk and adverse effects of SAM. As the standard of care shifts towards surgical and transcatheter interventions, it is increasingly important to better understand SAM biomechanics, and our advances represent a significant step towards that goal.
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Insuficiencia de la Válvula Mitral , Válvula Mitral , Animales , Porcinos , Fenómenos Biomecánicos , Válvula Mitral/cirugía , Insuficiencia de la Válvula Mitral/cirugía , Sístole , EcocardiografíaRESUMEN
INTRODUCTION: Central venous catheters (CVCs) are often trimmed during heart transplantation and pediatric cardiac surgery. However, the risk of endothelial injury caused by the cut tip of the CVC has not been evaluated. We hypothesized that there is no difference in the degree of endothelial injury associated with trimmed CVCs versus standard untrimmed CVCs. METHODS: In four adult male sheep, the left external jugular vein was exposed in three segments, one designated for an untouched control group, one for the trimmed CVC group, and one for the untrimmed CVC group. Trimmed and untrimmed CVC tips were rotated circumferentially within their respective segments to abrade the lumen of the vein. The vein samples were explanted, and two representative sections from each sample were analyzed using hematoxylin and eosin (H&E) staining, as well as with immunohistochemistry against CD31, von Willebrand factor (vWF), endothelial nitric oxide synthase (eNOS), and caveolin. Higher immunohistochemical stain distributions and intensities are associated with normal health and function of the venous endothelium. Data are presented as counts with percentages or as means with standard error. RESULTS: H&E staining revealed no evidence of endothelial injury in 6/8 (75%) samples from the untouched control group, and no injury in 4/8 (50%) samples from both the trimmed and untrimmed CVC groups (p = 0.504). In all remaining samples from each group, only mild endothelial injury was observed. Immunohistochemical analysis comparing trimmed CVCs versus untrimmed CVCs revealed no difference in the percentage of endothelial cells staining positive for CD31 (57.5% ± 7.2% vs 55.0% ± 9.2%, p = 0.982), vWF (73.8% ± 8.0% vs 62.5% ± 9.6%, p = 0.579), eNOS (66.3% ± 4.2% vs 63.8% ± 7.5%, p = 0.962), and caveolin (53.8% ± 5.0% vs 51.3% ± 4.4%, p = 0.922). There were no significant differences between the groups in the distributions of stain intensity for CD31, vWF, eNOS, and caveolin. CONCLUSION: Trimmed CVCs do not increase endothelial injury compared to standard untrimmed CVCs.
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Background: Several conduit configurations, such as straight graft (SG), Valsalva graft (VG), anticommissural plication (ACP), and the Stanford modification (SMOD) technique, have been described for the valve-sparing aortic root replacement (VSARR) procedure. Prior ex vivo studies have evaluated the impact of conduit configurations on root biomechanics, but the mock coronary artery circuits used could not replicate the physical properties of native coronary arteries. Moreover, the individual leaflet's biomechanics, including the fluttering phenomenon, were unclear. Methods: Porcine aortic roots with coronary arteries were explanted (n=5) and underwent VSARR using SG, VG, ACP, and SMOD for evaluation in an ex vivo left heart flow loop simulator. Additionally, 762 patients who underwent VSARR from 1993 through 2022 at our center were retrospectively reviewed. Analysis of variance was performed to evaluate differences between different conduit configurations, with post hoc Tukey's correction for pairwise testing. Results: SG demonstrated lower rapid leaflet opening velocity compared with VG (P=0.001) and SMOD (P=0.045) in the left coronary cusp (LCC), lower rapid leaflet closing velocity compared with VG (P=0.04) in the right coronary cusp (RCC), and lower relative opening force compared with ACP (P=0.04) in the RCC. The flutter frequency was lower in baseline compared with VG (P=0.02) and in VG compared with ACP (P=0.03) in the LCC. Left coronary artery mean flow was higher in SG compared with SMOD (P=0.02) and ACP (P=0.05). Clinically, operations using SG compared with sinus-containing graft was associated with shorter aortic cross-clamp and cardiopulmonary bypass time (P<0.001, <0.001). Conclusions: SG demonstrated hemodynamics and biomechanics most closely recapitulating those from the native root with significantly shorter intraoperative times compared with repair using sinus-containing graft. Future in vivo validation studies as well as correlation with comprehensive, comparative clinical study outcomes may provide additional invaluable insights regarding strategies to further enhance repair durability.
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BACKGROUND: The 6-year Integrated Thoracic Surgery (I-6) residency programs have evolved over the past decade. Despite the rising number of programs, there are minimal data published about the criteria utilized by program directors to select candidates. We analyze the characteristics and qualities of successful matriculants using the American Association of Medical College's (AAMC) data reports and survey responses from program directors. METHODS: Using a survey administered through the RedCap service, program directors were asked to rate the importance of a variety of factors in their evaluations of candidates. The AAMC data reports from 2018 to 2020 provided information on the mean matriculant research productivity, United States Medical Licensing Examination (USMLE) step 1 scores, and step 2 clinical knowledge (CK) scores. RESULTS: Responses were received from 19 of 33 I-6 programs (58%). Program directors consistently rated interview performance as a very important factor in their evaluation of applicants. Matching into the specialty is becoming more competitive, with mean USMLE step 1, step 2 CK, and research productivity increasing over the past few years; matriculants had mean step 1 and step 2 CK scores of 247.3 and 254.2, respectively, in the 2020 match. CONCLUSIONS: Thoracic surgery program directors place high value on applicant interview performance, letters of recommendation, and professionalism. Program directors agree that a forthcoming pass/fail USMLE step 1 score report will lead to closer scrutiny of other factors during the decision-making process and may cause future evaluation of applicants to be heavily reliant on letters of recommendation and medical school pedigree.
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Internado y Residencia , Cirugía Torácica , Humanos , Criterios de Admisión Escolar , Facultades de Medicina , Encuestas y Cuestionarios , Estados UnidosRESUMEN
Peripheral artery disease and the associated ischemic wounds are substantial causes of global morbidity and mortality, affecting over 200 million people worldwide. Although advancements have been made in preventive, pharmacologic, and surgical strategies to treat this disease, ischemic wounds, a consequence of end-stage peripheral artery disease, remain a significant clinical and economic challenge. Synechococcus elongatus is a cyanobacterium that grows photoautotrophically and converts carbon dioxide and water into oxygen. We present a novel topical biologic gel containing S. elongatus that provides oxygen via photosynthesis to augment wound healing by rescuing ischemic tissues caused by peripheral artery disease. By using light rather than blood as a source of energy, our novel topical therapy significantly accelerated wound healing in two rodent ischemic wound models. This novel topical gel can be directly translated to clinical practice by using a localized, portable light source without interfering with patients' daily activities, demonstrating potential to generate a paradigm shift in treating ischemic wounds from peripheral artery disease. Its novelty, low production cost, and ease of clinical translatability can potentially impact the clinical care for millions of patients suffering from peripheral arterial disease.
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Productos Biológicos , Enfermedad Arterial Periférica , Geles , Humanos , Isquemia , Oxígeno , Enfermedad Arterial Periférica/terapia , Fotosíntesis , Cicatrización de HeridasRESUMEN
OBJECTIVES: Neonatal rodents and piglets naturally regenerate the injured heart after myocardial infarction. We hypothesized that neonatal rabbits also exhibit natural heart regeneration after myocardial infarction. METHODS: New Zealand white rabbit kits underwent sham surgery or left coronary ligation on postnatal day 1 (n = 94), postnatal day 4 (n = 11), or postnatal day 7 (n = 52). Hearts were explanted 1 day postsurgery to confirm ischemic injury, at 1 week postsurgery to assess cardiomyocyte proliferation, and at 3 weeks postsurgery to assess left ventricular ejection fraction and scar size. Data are presented as mean ± standard deviation. RESULTS: Size of ischemic injury as a percentage of left ventricular area was similar after myocardial infarction on postnatal day 1 versus on postnatal day 7 (42.3% ± 5.4% vs 42.3% ± 4.7%, P = .9984). Echocardiography confirmed severely reduced ejection fraction at 1 day after postnatal day 1 myocardial infarction (33.7% ± 5.3% vs 65.2% ± 5.5% for postnatal day 1 sham, P = .0001), but no difference at 3 weeks after postnatal day 1 myocardial infarction (56.0% ± 4.0% vs 58.0% ± 3.3% for postnatal day 1 sham, P = .2198). Ejection fraction failed to recover after postnatal day 4 myocardial infarction (49.2% ± 1.8% vs 58.5% ± 5.8% for postnatal day 4 sham, P = .0109) and postnatal day 7 myocardial infarction (39.0% ± 7.8% vs 60.2% ± 5.0% for postnatal day 7 sham, P < .0001). At 3 weeks after infarction, fibrotic scar represented 5.3% ± 1.9%, 14.3% ± 4.9%, and 25.4% ± 13.3% of the left ventricle area in the postnatal day 1, postnatal day 4, and postnatal day 7 groups, respectively. An increased proportion of peri-infarct cardiomyocytes expressed Ki67 (15.9% ± 1.8% vs 10.2% ± 0.8%, P = .0039) and aurora B kinase (4.0% ± 0.9% vs 1.5% ± 0.6%, P = .0088) after postnatal day 1 myocardial infarction compared with sham, but no increase was observed after postnatal day 7 myocardial infarction. CONCLUSIONS: A neonatal leporine myocardial infarction model reveals that newborn rabbits are capable of age-dependent natural heart regeneration.
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Infarto del Miocardio , Función Ventricular Izquierda , Animales , Conejos , Cicatriz , Corazón/diagnóstico por imagen , Infarto del Miocardio/diagnóstico por imagen , Miocitos Cardíacos , Regeneración , Volumen Sistólico , PorcinosRESUMEN
Resource-scarce regions with serious COVID-19 outbreaks do not have enough ventilators to support critically ill patients, and these shortages are especially devastating in developing countries. To help alleviate this strain, we have designed and tested the accessible low-barrier in vivo-validated economical ventilator (ALIVE Vent), a COVID-19-inspired, cost-effective, open-source, in vivo-validated solution made from commercially available components. The ALIVE Vent operates using compressed oxygen and air to drive inspiration, while two solenoid valves ensure one-way flow and precise cycle timing. The device was functionally tested and profiled using a variable resistance and compliance artificial lung and validated in anesthetized large animals. Our functional test results revealed its effective operation under a wide variety of ventilation conditions defined by the American Association of Respiratory Care guidelines for ventilator stockpiling. The large animal test showed that our ventilator performed similarly if not better than a standard ventilator in maintaining optimal ventilation status. The FiO2, respiratory rate, inspiratory to expiratory time ratio, positive-end expiratory pressure, and peak inspiratory pressure were successfully maintained within normal, clinically validated ranges, and the animals were recovered without any complications. In regions with limited access to ventilators, the ALIVE Vent can help alleviate shortages, and we have ensured that all used materials are publicly available. While this pandemic has elucidated enormous global inequalities in healthcare, innovative, cost-effective solutions aimed at reducing socio-economic barriers, such as the ALIVE Vent, can help enable access to prompt healthcare and life saving technology on a global scale and beyond COVID-19. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s42242-021-00164-1.