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2.
J Am Coll Cardiol ; 78(1): 1-9, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-33945832

RESUMO

BACKGROUND: Transcatheter edge-to-edge (TEER) mitral repair may be complicated by residual or recurrent mitral regurgitation. An increasing need for surgical reintervention has been reported, but operative outcomes are ill defined. OBJECTIVES: This study evaluated national outcomes of mitral surgery after TEER. METHODS: The Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database was used to identify 524 adults who underwent mitral surgery after TEER between July 2014 and June 2020. Emergencies (5.0%; n = 26), previous mitral surgery (5.3%; n = 28), or open implantation of transcatheter prostheses (1.5%; n = 8) were excluded. The primary outcome was 30-day or in-hospital mortality. RESULTS: In the study cohort of 463 patients, the median age was 76 years (interquartile range [IQR]: 67 to 81 years), median left ventricular ejection fraction was 57% (IQR: 48% to 62%), and 177 (38.2%) patients had degenerative disease. Major concomitant cardiac surgery was performed in 137 (29.4%) patients: in patients undergoing isolated mitral surgery, the median STS-predicted mortality was 6.5% (IQR: 3.9% to 10.5%), the observed mortality was 10.2% (n = 23 of 225), and the ratio of observed to expected mortality was 1.2 (95% confidence interval [CI]: 0.8 to 1.9). Predictors of mortality included urgent surgery (odds ratio [OR]: 2.4; 95% CI: 1.3 to 4.6), nondegenerative/unknown etiology (OR: 2.2; 95% CI: 1.1 to 4.5), creatinine of >2.0 mg/dl (OR: 3.8; 95% CI: 1.9 to 7.9) and age of >80 years (OR: 2.1; 95% CI: 1.1 to 4.4). In a volume outcomes analysis in an expanded cohort of 591 patients at 227 hospitals, operative mortality was 2.6% (n = 2 of 76) in 4 centers that performed >10 cases versus 12.4% (n = 64 of 515) in centers performing fewer (p = 0.01). The surgical repair rate after failed TEER was 4.8% (n = 22) and was 6.8% (n = 12) in degenerative disease. CONCLUSIONS: This study indicates that mitral repair is infrequently achieved after failed TEER, which may have implications for treatment choice in lower-risk and younger patients with degenerative disease. These findings should inform patient consent for TEER, clinical trial design, and clinical performance measures.


Assuntos
Cateterismo Cardíaco , Implante de Prótese de Valva Cardíaca , Anuloplastia da Valva Mitral/efeitos adversos , Insuficiência da Valva Mitral , Valva Mitral , Complicações Pós-Operatórias , Reoperação , Fatores Etários , Idoso , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/métodos , Feminino , Doenças das Valvas Cardíacas/patologia , Doenças das Valvas Cardíacas/cirurgia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/métodos , Mortalidade Hospitalar , Humanos , Masculino , Valva Mitral/diagnóstico por imagem , Valva Mitral/patologia , Valva Mitral/cirurgia , Anuloplastia da Valva Mitral/métodos , Insuficiência da Valva Mitral/diagnóstico , Insuficiência da Valva Mitral/etiologia , Insuficiência da Valva Mitral/mortalidade , Insuficiência da Valva Mitral/cirurgia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/cirurgia , Prognóstico , Recidiva , Reoperação/efeitos adversos , Reoperação/métodos , Reoperação/estatística & dados numéricos , Fatores de Risco , Estados Unidos
4.
J Cardiovasc Dev Dis ; 7(4)2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33212844

RESUMO

The clinical efficacy of neuregulin (NRG) in the treatment of heart failure is hindered by off-target exposure due to systemic delivery. We previously encapsulated neuregulin in a hydrogel (HG) for targeted and sustained myocardial delivery, demonstrating significant induction of cardiomyocyte proliferation and preservation of post-infarct cardiac function in a murine myocardial infarction (MI) model. Here, we performed a focused evaluation of our hydrogel-encapsulated neuregulin (NRG-HG) therapy's potential to enhance cardiac function in an ovine large animal MI model. Adult male Dorset sheep (n = 21) underwent surgical induction of MI by coronary artery ligation. The sheep were randomized to receive an intramyocardial injection of saline, HG only, NRG only, or NRG-HG circumferentially around the infarct borderzone. Eight weeks after MI, closed-chest intracardiac pressure-volume hemodynamics were assessed, followed by heart explant for infarct size analysis. Compared to each of the control groups, NRG-HG significantly augmented left ventricular ejection fraction (p = 0.006) and contractility based on the slope of the end-systolic pressure-volume relationship (p = 0.006). NRG-HG also significantly reduced infarct scar size (p = 0.002). Overall, using a bioengineered hydrogel delivery system, a one-time dose of NRG delivered intramyocardially to the infarct borderzone at the time of MI in adult sheep significantly reduces scar size and enhances ventricular contractility at 8 weeks after MI.

6.
J Am Heart Assoc ; 9(6): e014345, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32131688

RESUMO

Background Induced pluripotent stem cells and their differentiated cardiomyocytes (iCMs) have tremendous potential as patient-specific therapy for ischemic cardiomyopathy following myocardial infarctions, but difficulties in viable transplantation limit clinical translation. Exosomes secreted from iCMs (iCM-Ex) can be robustly collected in vitro and injected in lieu of live iCMs as a cell-free therapy for myocardial infarction. Methods and Results iCM-Ex were precipitated from iCM supernatant and characterized by protein marker expression, nanoparticle tracking analysis, and functionalized nanogold transmission electron microscopy. iCM-Ex were then used in in vitro and in vivo models of ischemic injuries. Cardiac function in vivo was evaluated by left ventricular ejection fraction and myocardial viability measurements by magnetic resonance imaging. Cardioprotective mechanisms were studied by JC-1 (tetraethylbenzimidazolylcarbocyanine iodide) assay, immunohistochemistry, quantitative real-time polymerase chain reaction, transmission electron microscopy, and immunoblotting. iCM-Ex measured ≈140 nm and expressed CD63 and CD9. iCM and iCM-Ex microRNA profiles had significant overlap, indicating that exosomal content was reflective of the parent cell. Mice treated with iCM-Ex demonstrated significant cardiac improvement post-myocardial infarction, with significantly reduced apoptosis and fibrosis. In vitro iCM apoptosis was significantly reduced by hypoxia and exosome biogenesis inhibition and restored by treatment with iCM-Ex or rapamycin. Autophagosome production and autophagy flux was upregulated in iCM-Ex groups in vivo and in vitro. Conclusions iCM-Ex improve post-myocardial infarction cardiac function by regulating autophagy in hypoxic cardiomyoytes, enabling a cell-free, patient-specific therapy for ischemic cardiomyopathy.


Assuntos
Autofagia , Exossomos/transplante , Células-Tronco Pluripotentes Induzidas/transplante , Infarto do Miocárdio/terapia , Miocárdio/ultraestrutura , Miócitos Cardíacos/transplante , Animais , Apoptose , Proteínas Relacionadas à Autofagia/metabolismo , Hipóxia Celular , Linhagem Celular , Modelos Animais de Doenças , Exossomos/metabolismo , Exossomos/ultraestrutura , Feminino , Fibrose , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/ultraestrutura , Camundongos SCID , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/ultraestrutura , Recuperação de Função Fisiológica , Transdução de Sinais , Volume Sistólico , Função Ventricular Esquerda
8.
J Thorac Cardiovasc Surg ; 159(2): 477-486.e3, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31053433

RESUMO

OBJECTIVE: The study objective was to compare outcomes for patients with and without acute kidney injury during hospitalizations when left ventricular assist devices are implanted. METHODS: By using the National Inpatient Sample from 2008 to 2013, we identified patients with an International Classification of Diseases, Ninth Revision procedure code for left ventricular assist device implantation (37.66). We ascertained the presence of acute kidney injury and acute kidney injury requiring dialysis using validated International Classification of Diseases, Ninth Revision codes. We used logistic regression to examine the association of nondialysis-requiring acute kidney injury and acute kidney injury requiring dialysis with mortality, procedural complications, and discharge destination. RESULTS: We identified 8362 patients who underwent left ventricular assist device implantation, of whom 3760 (45.0%) experienced nondialysis-requiring acute kidney injury and 426 (5.1%) experienced acute kidney injury requiring dialysis. In-hospital mortality was 3.9% for patients without acute kidney injury, 12.2% for patients with nondialysis-requiring acute kidney injury, and 47.4% for patients with acute kidney injury requiring dialysis. Patients with nondialysis-requiring acute kidney injury and acute kidney injury requiring dialysis had higher adjusted odds of mortality (3.24, 95% confidence interval [CI], 2.04-5.13 and 20.8, 95% CI, 9.7-44.2), major bleeding (1.38, 95% CI, 1.08-1.77 and 2.44, 95% CI, 1.47-4.04), sepsis (2.69, 95% CI, 1.93-3.75 and 5.75, 95% CI, 3.46-9.56), and discharge to a nursing facility (2.15, 95% CI, 1.51-3.07 and 5.89, 95% CI, 2.67-12.99). CONCLUSIONS: More than 1 in 10 patients with acute kidney injury and approximately 1 in 2 patients with acute kidney injury requiring dialysis died during their hospitalization, with only 30% of patients with acute kidney injury requiring dialysis discharged to home. This information is necessary to support shared decision-making for patients with advanced heart failure and acute kidney injury.


Assuntos
Injúria Renal Aguda/complicações , Procedimentos Cirúrgicos Cardíacos , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/cirurgia , Coração Auxiliar , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/instrumentação , Procedimentos Cirúrgicos Cardíacos/mortalidade , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Resultado do Tratamento
9.
Eur J Cardiothorac Surg ; 57(1): 63-71, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31006006

RESUMO

OBJECTIVES: Neurodevelopmental disability is the most common complication among congenital heart surgery survivors. The Bayley scales are standardized instruments to assess neurodevelopment. The most recent edition (Bayley Scales of Infant and Toddler Development 3rd Edition, Bayley-III) yields better-than-expected scores in typically developing and high-risk infants than the second edition (Bayley Scales of Infant Development 2nd Edition, BSID-II). We compared BSID-II and Bayley-III scores in infants undergoing cardiac surgery. METHODS: We evaluated 2198 infants who underwent operations with cardiopulmonary bypass between 1996 and 2009 at 26 institutions. We used propensity score matching to limit confounding by indication in a subset of patients (n = 705). RESULTS: Overall, unadjusted Bayley-III motor scores were higher than BSID-II Psychomotor Development Index scores (90.7 ± 17.2 vs 77.6 ± 18.8, P < 0.001), and unadjusted Bayley-III composite cognitive and language scores were higher than BSID-II Mental Development Index scores (92.0 ± 15.4 vs 88.2 ± 16.7, P < 0.001). In the propensity-matched analysis, Bayley-III motor scores were higher than BSID-II Psychomotor Development Index scores [absolute difference 14.1, 95% confidence interval (CI) 11.7-17.6; P < 0.001] and the Bayley-III classified fewer children as having severe [odds ratio (OR) 0.24; 95% CI 0.14-0.42] or mild-to-moderate impairment (OR 0.21; 95% CI 0.14-0.32). The composite of Bayley-III cognitive and language scores was higher than BSID-II Mental Development Index scores (absolute difference 4.0, 95% CI 1.4-6.7; P = 0.003), but there was no difference between Bayley editions in the proportion of children classified as having severe cognitive and language impairment. CONCLUSIONS: The Bayley-III yielded higher scores than the BSID-II and classified fewer children as severely impaired. The systematic bias towards higher scores with the Bayley-III precludes valid comparisons between early and contemporary cardiac surgery cohorts.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Deficiências do Desenvolvimento , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Ponte Cardiopulmonar , Criança , Desenvolvimento Infantil , Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/epidemiologia , Deficiências do Desenvolvimento/etiologia , Humanos , Lactente
11.
Circulation ; 140(15): 1239-1250, 2019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-31589488

RESUMO

BACKGROUND: The feasibility and effectiveness of delaying surgery to transfer patients with acute type A aortic dissection-a catastrophic disease that requires prompt intervention-to higher-volume aortic surgery hospitals is unknown. We investigated the hypothesis that regionalizing care at high-volume hospitals for acute type A aortic dissections will lower mortality. We further decomposed this hypothesis into subparts, investigating the isolated effect of transfer and the isolated effect of receiving care at a high-volume versus a low-volume facility. METHODS: We compared the operative mortality and long-term survival between 16 886 Medicare beneficiaries diagnosed with an acute type A aortic dissection between 1999 and 2014 who (1) were transferred versus not transferred, (2) underwent surgery at high-volume versus low-volume hospitals, and (3) were rerouted versus not rerouted to a high-volume hospital for treatment. We used a preference-based instrumental variable design to address unmeasured confounding and matching to separate the effect of transfer from volume. RESULTS: Between 1999 and 2014, 40.5% of patients with an acute type A aortic dissection were transferred, and 51.9% received surgery at a high-volume hospital. Interfacility transfer was not associated with a change in operative mortality (risk difference, -0.69%; 95% CI, -2.7% to 1.35%) or long-term mortality. Despite delaying surgery, a regionalization policy that transfers patients to high-volume hospitals was associated with a 7.2% (95% CI, 4.1%-10.3%) absolute risk reduction in operative mortality; this association persisted in the long term (hazard ratio, 0.81; 95% CI, 0.75-0.87). The median distance needed to reroute each patient to a high-volume hospital was 50.1 miles (interquartile range, 12.4-105.4 miles). CONCLUSIONS: Operative and long-term mortality were substantially reduced in patients with acute type A aortic dissection who were rerouted to high-volume hospitals. Policy makers should evaluate the feasibility and benefits of regionalizing the surgical treatment of acute type A aortic dissection in the United States.


Assuntos
Aneurisma Dissecante/mortalidade , Aneurisma Aórtico/mortalidade , Hospitais com Alto Volume de Atendimentos , Hospitais com Baixo Volume de Atendimentos/métodos , Medicare , Transferência de Pacientes/métodos , Idoso , Idoso de 80 Anos ou mais , Aneurisma Dissecante/diagnóstico , Aneurisma Dissecante/cirurgia , Aorta/patologia , Aorta/cirurgia , Aneurisma Aórtico/diagnóstico , Aneurisma Aórtico/cirurgia , Estudos de Coortes , Feminino , Mortalidade Hospitalar/tendências , Hospitais com Alto Volume de Atendimentos/tendências , Hospitais com Baixo Volume de Atendimentos/tendências , Humanos , Masculino , Medicare/tendências , Transferência de Pacientes/tendências , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Resultado do Tratamento , Estados Unidos/epidemiologia
14.
J Thorac Cardiovasc Surg ; 158(2): 392-403, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30745047

RESUMO

OBJECTIVE: The optimal conduit for valve-sparing aortic root replacement is still debated, with several conduit variations available, ranging from straight tubular grafts to Valsalva grafts. Benefits of neosinus reconstruction include enhanced flow profiles and improved hemodynamics. Curiously, however, some clinical data suggest that straight grafts may have greater long-term durability. In this study, we hypothesized that straight tubular grafts may help maintain the native cylindrical position of the aortic valve commissures radially, resulting in preserved leaflet coaptation, reduced stresses, and potentially improved valve performance. METHODS: Using 3D printing, a left heart simulator with a valve-sparing root replacement model and a physiologic coronary circulation was constructed. Aortic valves were dissected from fresh porcine hearts and reimplanted into either straight tubular grafts (n = 6) or Valsalva grafts (n = 6). Conduits were mounted into the heart simulator and hemodynamic, echocardiographic, and high-speed videometric data were collected. RESULTS: Hemodynamic parameters and coronary blood flow were similar between straight and Valsalva grafts, although the former were associated with lower regurgitant fractions, less peak intercommissural radial separation, preserved leaflet coaptation, decreased leaflet velocities, and lower relative leaflet forces compared with Valsalva grafts. CONCLUSIONS: Valsalva grafts and straight grafts perform equally well in terms of gross hemodyanics and coronary blood flow. Interestingly, however, the biomechanics of these 2 conduits differ considerably, with straight grafts providing increased radial commissural stability and leaflet coaptation. Further investigation into how these parameters influence clinical outcomes is warranted.


Assuntos
Aorta/cirurgia , Valva Aórtica/cirurgia , Impressão Tridimensional , Animais , Aorta/patologia , Aorta/fisiopatologia , Valva Aórtica/patologia , Valva Aórtica/fisiopatologia , Fenômenos Biomecânicos , Circulação Coronária , Ecocardiografia Transesofagiana , Hemodinâmica , Modelos Anatômicos , Seio Aórtico/patologia , Seio Aórtico/fisiopatologia , Seio Aórtico/cirurgia , Suínos , Enxerto Vascular/métodos
15.
J Thorac Cardiovasc Surg ; 158(3): 665-672, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30712911

RESUMO

OBJECTIVE: Neurologic injury complicating the presentation of acute type A aortic dissection remains a challenge for cardiac surgeons. METHODS: This was a retrospective review of patients undergoing open repair of acute type A aortic dissection at our institution between January 2005 and December 2015. Evidence of neurologic injury at the time of presentation was abstracted from the medical record. Propensity-score matching was used to account for baseline differences between groups, and outcome analysis was performed using logistic regression and Kaplan-Meier analysis. Among patients with persistent neurologic deficits, a threshold for time-to-operation was evaluated using receiver operating characteristic curves. RESULTS: There were 345 patients who underwent open repair for acute type A aortic dissection; 50 patients presented with neurologic injury. In the matched analysis, in-hospital mortality was greater among patients who presented with neurologic deficits (odds ratio, 4.42; 95% confidence interval, 1.15-16.97; P = .03). Among patients with persistent neurologic deficits at presentation, receiver operating characteristic curve analysis with cross-validation suggested that time-to-operation was a poor predictor of both neurologic outcome (area under the curve, 0.40) and death (area under the curve, 0.49). CONCLUSIONS: Neurologic injury at the time of presentation with acute type A aortic dissection was associated with an increased risk of in-hospital mortality. Among patients with persistent neurological deficits, time-to-operation failed to predict either neurologic outcome or perioperative mortality suggesting that longer time from onset of symptoms of neurologic injury should not act as a contraindication to proceeding to the operating room for expedient repair.


Assuntos
Aneurisma Dissecante/cirurgia , Aneurisma Aórtico/cirurgia , Doenças do Sistema Nervoso/complicações , Tempo para o Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Doença Aguda , Idoso , Aneurisma Dissecante/complicações , Aneurisma Dissecante/mortalidade , Aneurisma Dissecante/fisiopatologia , Aneurisma Aórtico/complicações , Aneurisma Aórtico/mortalidade , Aneurisma Aórtico/fisiopatologia , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/mortalidade , Doenças do Sistema Nervoso/fisiopatologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/mortalidade
16.
J Am Coll Cardiol ; 73(6): 643-651, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30765029

RESUMO

BACKGROUND: For the management of descending thoracic aortic aneurysms, recent evidence has suggested that outcomes of open surgical repair may surpass thoracic endovascular aortic repair (TEVAR) in as early as 2 years. OBJECTIVES: The purpose of this study was to evaluate the comparative effectiveness of TEVAR and open surgical repair in the treatment of intact descending thoracic aortic aneurysms. METHODS: Using the Medicare database, a retrospective study using regression discontinuity design and propensity score matching was performed on patients with intact descending thoracic aortic aneurysms who underwent TEVAR or open surgical repair between 1999 and 2010 with follow-up through 2014. Survival was assessed with restricted mean survival time. Perioperative mortality was assessed with logistic regression. Reintervention was evaluated as a secondary outcome. RESULTS: Matching created comparable groups with 1,235 open surgical repair patients matched to 2,470 TEVAR patients. The odds of perioperative mortality were greater for open surgical repair: high-volume center, odds ratio (OR): 1.97 (95% confidence interval [CI]: 1.53 to 2.61); low-volume center, OR: 3.62 (95% CI: 2.88 to 4.51). The restricted mean survival time difference favored TEVAR at 9 years, -209.2 days (95% CI: -298.7 to -119.7 days; p < 0.001) for open surgical repair. Risk of reintervention was lower for open surgical repair, hazard ratio: 0.40 (95% CI: 0.34 to 0.60; p < 0.001). CONCLUSIONS: Open surgical repair was associated with increased odds of early postoperative mortality but reduced late hazard of death. Despite the late advantage of open repair, mean survival was superior for TEVAR. TEVAR should be considered the first line for repair of intact descending thoracic aortic aneurysms in Medicare beneficiaries.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Torácica/complicações , Aneurisma da Aorta Torácica/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Pontuação de Propensão , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
18.
Cell ; 176(5): 1128-1142.e18, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30686582

RESUMO

Collateral arteries are an uncommon vessel subtype that can provide alternate blood flow to preserve tissue following vascular occlusion. Some patients with heart disease develop collateral coronary arteries, and this correlates with increased survival. However, it is not known how these collaterals develop or how to stimulate them. We demonstrate that neonatal mouse hearts use a novel mechanism to build collateral arteries in response to injury. Arterial endothelial cells (ECs) migrated away from arteries along existing capillaries and reassembled into collateral arteries, which we termed "artery reassembly". Artery ECs expressed CXCR4, and following injury, capillary ECs induced its ligand, CXCL12. CXCL12 or CXCR4 deletion impaired collateral artery formation and neonatal heart regeneration. Artery reassembly was nearly absent in adults but was induced by exogenous CXCL12. Thus, understanding neonatal regenerative mechanisms can identify pathways that restore these processes in adults and identify potentially translatable therapeutic strategies for ischemic heart disease.


Assuntos
Circulação Colateral/fisiologia , Coração/crescimento & desenvolvimento , Regeneração/fisiologia , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Quimiocina CXCL12/metabolismo , Vasos Coronários/crescimento & desenvolvimento , Células Endoteliais/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica/fisiologia , Receptores CXCR4/metabolismo , Transdução de Sinais
19.
Circulation ; 138(19): 2130-2144, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30474423

RESUMO

BACKGROUND: Cardiovascular bypass grafting is an essential treatment for complex cases of atherosclerotic disease. Because the availability of autologous arterial and venous conduits is patient-limited, self-assembled cell-only grafts have been developed to serve as functional conduits with off-the-shelf availability. The unacceptably long production time required to generate these conduits, however, currently limits their clinical utility. Here, we introduce a novel technique to significantly accelerate the production process of self-assembled engineered vascular conduits. METHODS: Human aortic smooth muscle cells and skin fibroblasts were used to construct bilevel cell sheets. Cell sheets were wrapped around a 22.5-gauge Angiocath needle to form tubular vessel constructs. A thin, flexible membrane of clinically approved biodegradable tissue glue (Dermabond Advanced) served as a temporary, external scaffold, allowing immediate perfusion and endothelialization of the vessel construct in a bioreactor. Subsequently, the matured vascular conduits were used as femoral artery interposition grafts in rats (n=20). Burst pressure, vasoreactivity, flow dynamics, perfusion, graft patency, and histological structure were assessed. RESULTS: Compared with engineered vascular conduits formed without external stabilization, glue membrane-stabilized conduits reached maturity in the bioreactor in one-fifth the time. After only 2 weeks of perfusion, the matured conduits exhibited flow dynamics similar to that of control arteries, as well as physiological responses to vasoconstricting and vasodilating drugs. The matured conduits had burst pressures exceeding 500 mm Hg and had sufficient mechanical stability for surgical anastomoses. The patency rate of implanted conduits at 8 weeks was 100%, with flow rate and hind-limb perfusion similar to those of sham controls. Grafts explanted after 8 weeks showed a histological structure resembling that of typical arteries, including intima, media, adventitia, and internal and external elastic membrane layers. CONCLUSIONS: Our technique reduces the production time of self-assembled, cell sheet-derived engineered vascular conduits to 2 weeks, thereby permitting their use as bypass grafts within the clinical time window for elective cardiovascular surgery. Furthermore, our method uses only clinically approved materials and can be adapted to various cell sources, simplifying the path toward future clinical translation.


Assuntos
Bioprótese , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Artéria Femoral/cirurgia , Músculo Liso Vascular/citologia , Engenharia Tecidual/métodos , Tecidos Suporte , Animais , Aorta/citologia , Velocidade do Fluxo Sanguíneo , Implante de Prótese Vascular/efeitos adversos , Células Cultivadas , Técnicas de Cocultura , Artéria Femoral/patologia , Artéria Femoral/fisiopatologia , Fibroblastos , Humanos , Masculino , Miócitos de Músculo Liso , Desenho de Prótese , Falha de Prótese , Ratos Nus , Fluxo Sanguíneo Regional , Estresse Mecânico , Resistência à Tração , Fatores de Tempo , Grau de Desobstrução Vascular
20.
J Thorac Cardiovasc Surg ; 156(6): 2216-2223, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30119904

RESUMO

OBJECTIVES: Although the importance of mentorship in training the next generation of cardiothoracic surgeons is widely recognized, the current state of mentorship remains undefined. METHODS: Trainee responses to questions in the 2017 In-Training Examination regarding aspects of mentorship were analyzed. Response rate was 78% (288/370). Mentor-related and trainee-related characteristics were assessed. RESULTS: The majority (84%) of residents had mentors, with a high impact on specialty choice (80%), and 91% of respondents viewed mentorship as critical to success. Nearly half (42%) had program-assigned mentors; 53% found them as productive, and 13% reported more consistent/frequent meetings than personally selected mentors, with 22% reporting less ideal personality match compared with personally selected mentors. Among residents with mentors, 36% lacked mentorship in work-life balance, 23% lacked mentorship in job assistance, and 22% lacked mentorship in career advice. Junior residents more often valued mentors as role models, whereas mentors chosen by senior residents were more impactful in technical training, job counseling, and societal involvement. Compared with men, women more often valued mentors as role models and assisting in networking. Men reported their mentors were more impactful in teaching technical skills and clinical ability than women. CONCLUSIONS: The majority of current cardiothoracic surgery trainees had mentorship; however, gaps remain: Many residents lacked career path guidance, assistance obtaining a job, and advice regarding life-work balance. The role of mentorship varied with program type, seniority, and gender, emphasizing the need to tailor mentorship to the individual and changing needs of the resident.


Assuntos
Procedimentos Cirúrgicos Cardíacos/educação , Educação de Pós-Graduação em Medicina/métodos , Internato e Residência , Mentores , Médicas , Cirurgiões/educação , Atitude do Pessoal de Saúde , Mobilidade Ocupacional , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Relações Interpessoais , Masculino , Médicas/psicologia , Cirurgiões/psicologia , Inquéritos e Questionários , Equilíbrio Trabalho-Vida
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