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1.
Plant Commun ; 5(6): 100846, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38460510

RESUMO

Allelochemicals represent a class of natural products released by plants as root, leaf, and fruit exudates that interfere with the growth and survival of neighboring plants. Understanding how allelochemicals function to regulate plant responses may provide valuable new approaches to better control plant function. One such allelochemical, Myrigalone A (MyA) produced by Myrica gale, inhibits seed germination and seedling growth through an unknown mechanism. Here, we investigate MyA using the tractable model Dictyostelium discoideum and reveal that its activity depends on the conserved homolog of the plant ethylene synthesis protein 1-aminocyclopropane-1-carboxylic acid oxidase (ACO). Furthermore, in silico modeling predicts the direct binding of MyA to ACO within the catalytic pocket. In D. discoideum, ablation of ACO mimics the MyA-dependent developmental delay, which is partially restored by exogenous ethylene, and MyA reduces ethylene production. In Arabidopsis thaliana, MyA treatment delays seed germination, and this effect is rescued by exogenous ethylene. It also mimics the effect of established ACO inhibitors on root and hypocotyl extension, blocks ethylene-dependent root hair production, and reduces ethylene production. Finally, in silico binding analyses identify a range of highly potent ethylene inhibitors that block ethylene-dependent response and reduce ethylene production in Arabidopsis. Thus, we demonstrate a molecular mechanism by which the allelochemical MyA reduces ethylene biosynthesis and identify a range of ultrapotent inhibitors of ethylene-regulated responses.


Assuntos
Arabidopsis , Etilenos , Feromônios , Etilenos/biossíntese , Etilenos/metabolismo , Feromônios/farmacologia , Feromônios/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/efeitos dos fármacos , Germinação/efeitos dos fármacos
2.
Otolaryngol Head Neck Surg ; 169(3): 701-709, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37003297

RESUMO

OBJECTIVE: Evaluate 2-year outcomes after lidocaine/epinephrine iontophoresis and tympanostomy using an automated tube delivery system for pediatric tube placement in-office. STUDY DESIGN: Prospective, single-arm. SETTING: Eighteen otolaryngology practices. METHODS: Children age 6 months to 12 years indicated for tympanostomy were enrolled between October 2017 and February 2019. Local anesthesia of the tympanic membrane was achieved via lidocaine/epinephrine iontophoresis and tympanostomy was completed using an automated tube delivery system (the Tula® System). An additional Lead-In cohort of patients underwent tube placement in the operating room (OR) under general anesthesia using only the tube delivery system. Patients were followed for 2 years or until tube extrusion, whichever occurred first. Otoscopy and tympanometry were performed at 3 weeks, and 6, 12, 18, and 24 months. Tube retention, patency, and safety were evaluated. RESULTS: Tubes were placed in-office for 269 patients (449 ears) and in the OR for 68 patients (131 ears) (mean age, 4.5 years). The median and mean times to tube extrusion for the combined OR and In-Office cohorts were 15.82 (95% confidence interval [CI]: 15.41-19.05) and 16.79 (95% CI: 16.16-17.42) months, respectively. Sequelae included ongoing perforation for 1.9% of ears (11/580) and medial tube displacement for 0.2% (1/580) observed at 18 months. Over a mean follow-up of 14.3 months, 30.3% (176/580) of ears had otorrhea and 14.3% (83/580) had occluded tubes. CONCLUSION: In-office pediatric tympanostomy using lidocaine/epinephrine iontophoresis and automated tube delivery results in tube retention within the ranges described for similar grommet-type tubes and complication rates consistent with traditional tube placement in the OR.


Assuntos
Iontoforese , Otite Média com Derrame , Criança , Humanos , Pré-Escolar , Lidocaína , Ventilação da Orelha Média/métodos , Estudos Prospectivos , Membrana Timpânica , Otite Média com Derrame/cirurgia
3.
Laryngoscope ; 130 Suppl 4: S1-S9, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32160320

RESUMO

OBJECTIVES/HYPOTHESIS: Evaluate technical success, tolerability, and safety of lidocaine iontophoresis and tympanostomy tube placement for children in an office setting. STUDY DESIGN: Prospective individual cohort study. METHODS: This prospective multicenter study evaluated in-office tube placement in children ages 6 months through 12 years of age. Anesthesia was achieved via lidocaine/epinephrine iontophoresis. Tube placement was conducted using an integrated and automated myringotomy and tube delivery system. Anxiolytics, sedation, and papoose board were not used. Technical success and safety were evaluated. Patients 5 to 12 years old self-reported tube placement pain using the Faces Pain Scale-Revised (FPS-R) instrument, which ranges from 0 (no pain) to 10 (very much pain). RESULTS: Children were enrolled into three cohorts with 68, 47, and 222 children in the Operating Room (OR) Lead-In, Office Lead-In, and Pivotal cohorts, respectively. In the Pivotal cohort, there were 120 and 102 children in the <5 and 5- to 12-year-old age groups, respectively, with a mean age of 2.3 and 7.6 years, respectively. Bilateral tube placement was indicated for 94.2% of children <5 and 88.2% of children 5 to 12 years old. Tubes were successfully placed in all indicated ears in 85.8% (103/120) of children <5 and 89.2% (91/102) of children 5 to 12 years old. Mean FPS-R score was 3.30 (standard deviation [SD] = 3.39) for tube placement and 1.69 (SD = 2.43) at 5 minutes postprocedure. There were no serious adverse events. Nonserious adverse events occurred at rates similar to standard tympanostomy procedures. CONCLUSIONS: In-office tube placement in selected patients can be successfully achieved without requiring sedatives, anxiolytics, or papoose restraints via lidocaine iontophoresis local anesthesia and an automated myringotomy and tube delivery system. LEVEL OF EVIDENCE: 2b Laryngoscope, 130:S1-S9, 2020.


Assuntos
Procedimentos Cirúrgicos Ambulatórios/métodos , Iontoforese/métodos , Ventilação da Orelha Média/métodos , Anestesia Local/métodos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Lidocaína/administração & dosagem , Masculino , Estudos Prospectivos , Resultado do Tratamento
4.
Dis Model Mech ; 11(1)2018 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-29361519

RESUMO

Natural compounds often have complex molecular structures and unknown molecular targets. These characteristics make them difficult to analyse using a classical pharmacological approach. Curcumin, the main curcuminoid of turmeric, is a complex molecule possessing wide-ranging biological activities, cellular mechanisms and roles in potential therapeutic treatment, including Alzheimer's disease and cancer. Here, we investigate the physiological effects and molecular targets of curcumin in Dictyostelium discoideum We show that curcumin exerts acute effects on cell behaviour, reduces cell growth and slows multicellular development. We employed a range of structurally related compounds to show the distinct role of different structural groups in curcumin's effects on cell behaviour, growth and development, highlighting active moieties in cell function, and showing that these cellular effects are unrelated to the well-known antioxidant activity of curcumin. Molecular mechanisms underlying the effect of curcumin and one synthetic analogue (EF24) were then investigated to identify a curcumin-resistant mutant lacking the protein phosphatase 2A regulatory subunit (PsrA) and an EF24-resistant mutant lacking the presenilin 1 orthologue (PsenB). Using in silico docking analysis, we then showed that curcumin might function through direct binding to a key regulatory region of PsrA. These findings reveal novel cellular and molecular mechanisms for the function of curcumin and related compounds.


Assuntos
Curcumina/farmacologia , Dictyostelium/metabolismo , Presenilina-1/metabolismo , Proteína Fosfatase 2/metabolismo , Homologia de Sequência de Aminoácidos , Antioxidantes/farmacologia , Curcumina/análogos & derivados , Curcumina/química , Dictyostelium/efeitos dos fármacos , Dictyostelium/crescimento & desenvolvimento , Ligantes , Simulação de Acoplamento Molecular
5.
Artigo em Inglês | MEDLINE | ID: mdl-27307549

RESUMO

BACKGROUND: Previously, through the use of computed tomography (CT), it has been proposed that D-shaped versus saddle-shaped mitral annulus (MA) segmentation is more biomechanically appropriate to determine transcatheter mitral valve implantation size and eligibility. METHODS AND RESULTS: Forty-one patients with severe mitral regurgitation being considered for transcatheter mitral valve implantation who had undergone cardiac CT and 3-dimensional transesophageal echocardiography (3D-TEE) were retrospectively evaluated. A standardized segmentation protocol for the D-shaped MA was developed using Philips Q-Laboratory mitral valve quantification software. MA dimensions were compared using Spearman's rank correlation and Bland-Altman analysis. Inter- and intraobserver agreement was quantified by intraclass correlation coefficient and Bland-Altman analysis. Mean age was 77±14 years; 71% male (n=29); mitral regurgitation pathogenesis was functional in 54% (n=22) and myxomatous in 46% (n=19). Mean MA area and circumference by 3D-TEE and CT were 11.3±2.7 versus 11.4±3.0 (P=0.67) and 124.1±15.6 versus 123.9±15.5 (P=0.79), respectively, with excellent correlation between modalities (r=0.84 and r=0.86; P<0.0001) and no systematic bias (-0.20±1.8 cm(2) [-3.7 cm(2); 3.3 cm(2)], 0.37±9 mm [-18.0 mm; 17.27 mm]). Mean septal-to-lateral and inter-trigone distances by 3D-TEE and CT were 33.2±4.7 versus 32.5±4.4 (P=0.24) and 31.7±3.5 versus 32.6±3.6 (P=0.06), respectively, with good correlation (r=0.69 and r=0.71; P<0.0001) and no systematic bias (0.77±3.8 mm [-6.7 mm; 8.2 mm], -1.5±3.1 mm [-4.6 mm; 7.6 mm]). There was excellent intra- and interobserver agreement according to intraclass correlation coefficients >0.90 for all parameters. CONCLUSIONS: Similar to cardiac CT, 3D-TEE allows for D-shaped MA segmentation with no systematic difference in MA dimensions between modalities. This study supports the utilization of 3D-TEE as a complementary tool to CT assessment of the D-shaped MA to determine transcatheter mitral valve implantation size.


Assuntos
Cateterismo Cardíaco/instrumentação , Ecocardiografia Tridimensional , Ecocardiografia Transesofagiana , Implante de Prótese de Valva Cardíaca/instrumentação , Próteses Valvulares Cardíacas , Insuficiência da Valva Mitral/diagnóstico por imagem , Valva Mitral/diagnóstico por imagem , Tomografia Computadorizada Multidetectores , Idoso , Idoso de 80 Anos ou mais , Cateterismo Cardíaco/métodos , Estudos de Viabilidade , Feminino , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/fisiopatologia , Insuficiência da Valva Mitral/fisiopatologia , Insuficiência da Valva Mitral/terapia , Variações Dependentes do Observador , Valor Preditivo dos Testes , Desenho de Prótese , Interpretação de Imagem Radiográfica Assistida por Computador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença
6.
Magn Reson Med ; 75(1): 345-55, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25752499

RESUMO

PURPOSE: Lymphatic impairment is known to reduce quality of life in some of the most crippling diseases of the 21st century, including obesity, lymphedema, and cancer. However, the lymphatics are not nearly as well-understood as other bodily systems, largely owing to a lack of sensitive imaging technologies that can be applied using standard clinical equipment. Here, proton exchange-weighted MRI is translated to the lymphatics in patients with breast cancer treatment-related lymphedema (BCRL). METHODS: Healthy volunteers (N = 8) and BCRL patients (N = 7) were scanned at 3 Tesla using customized structural MRI and amide proton transfer (APT) chemical exchange saturation transfer (CEST) MRI in sequence with the hypothesis that APT effects would be elevated in lymphedematous tissue. APT contrast, lymphedema stage, symptomatology, and histology information were evaluated. RESULTS: No significant difference between proton-weighted APT contrast in the right and left arms of healthy controls was observed. An increase in APT contrast in the affected arms of patients was found (P = 0.025; Cohen's d = 2.4), and variability among patients was consistent with documented damage to lymphatics as quantified by lymphedema stage. CONCLUSION: APT CEST MRI may have relevance for evaluating lymphatic impairment in patients with BCRL, and may extend to other pathologies where lymphatic compromise is evident.


Assuntos
Neoplasias da Mama/complicações , Neoplasias da Mama/patologia , Linfedema/etiologia , Linfedema/patologia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Proteínas/metabolismo , Adulto , Idoso , Biomarcadores/metabolismo , Neoplasias da Mama/terapia , Feminino , Humanos , Linfonodos , Linfedema/metabolismo , Pessoa de Meia-Idade , Imagem Molecular/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
7.
Nat Cell Biol ; 16(1): 87-98, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24335649

RESUMO

Rab GTPases play key roles in the delivery, docking and fusion of intracellular vesicles. However, the mechanism by which spatial and temporal regulation of Rab GTPase activity is controlled is poorly understood. Here we describe a mechanism by which localized calcium release through a vesicular ion channel controls Rab GTPase activity. We show that activation of P2XA, an intracellular ion channel localized to the Dictyostelium discoideum contractile vacuole system, results in calcium efflux required for downregulation of Rab11a activity and efficient vacuole fusion. Vacuole fusion and Rab11a downregulation require the activity of CnrF, an EF-hand-containing Rab GAP found in a complex with Rab11a and P2XA. CnrF Rab GAP activity for Rab11a is enhanced by the presence of calcium and the EF-hand domain. These findings suggest that P2XA activation results in vacuolar calcium release, which triggers activation of CnrF Rab GAP activity and subsequent downregulation of Rab11a to allow vacuole fusion.


Assuntos
Cálcio/farmacologia , Vesículas Citoplasmáticas/metabolismo , Dictyostelium/metabolismo , Espaço Intracelular/metabolismo , Fusão de Membrana , Receptores Purinérgicos P2X/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Trifosfato de Adenosina/farmacologia , Vesículas Citoplasmáticas/efeitos dos fármacos , Dictyostelium/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Proteínas Ativadoras de GTPase/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Espaço Intracelular/efeitos dos fármacos , Ativação do Canal Iônico/efeitos dos fármacos , Fusão de Membrana/efeitos dos fármacos , Microscopia de Fluorescência , Mutação/genética , Osmorregulação/efeitos dos fármacos , Fenótipo , Ligação Proteica/efeitos dos fármacos , Proteínas de Protozoários/metabolismo , Vacúolos/efeitos dos fármacos , Vacúolos/metabolismo , Proteínas rab de Ligação ao GTP/antagonistas & inibidores
8.
Can J Cardiol ; 29(11): 1454-61, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23927867

RESUMO

BACKGROUND: Marked variation exists concerning the utilization of percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG). The objective of this study was to examine differences in predictors of mode of revascularization across 3 provincial jurisdictions. METHODS: All patients who underwent PCI and isolated CABG in British Columbia, Alberta, and Nova Scotia between 1996 and 2007 were considered. Age- and sex-standardized rates of PCI and CABG per 100,000 population and PCI to CABG ratios were calculated by year and province. Logistic regression models were constructed to identify independent predictors of mode of revascularization in each province. RESULTS: A total of 32,190 and 69,409 patients underwent CABG and PCI, respectively, during the study period. Significant increases in the age- and sex-adjusted PCI to CABG ratios were observed in all 3 provinces, but these ratios differed between provinces. Across all 3 jurisdictions, female sex and diagnosis of acute coronary syndrome favoured increased PCI vs CABG, and increased age, left main, or 3-vessel disease occurring before myocardial infarction, and diabetes favoured lower PCI vs CABG. After adjusting for clinical and angiographic factors, there remained a significant variation in choice of PCI vs CABG between the 3 provinces over time. CONCLUSIONS: Significant interprovincial variability in PCI to CABG ratios was observed. Though certain patient-related factors predictive of either PCI or CABG were identified, factors beyond clinical presentation played a role in the choice of revascularization approach.


Assuntos
Ponte de Artéria Coronária/estatística & dados numéricos , Intervenção Coronária Percutânea/estatística & dados numéricos , Governo Estadual , Síndrome Coronariana Aguda/epidemiologia , Síndrome Coronariana Aguda/terapia , Adulto , Distribuição por Idade , Idoso , Canadá/epidemiologia , Cardiologia , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/terapia , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/terapia , Distribuição por Sexo , Recursos Humanos , Adulto Jovem
9.
J Biol Chem ; 288(29): 20992-21000, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23740252

RESUMO

The Dictyostelium discoideum genome encodes five proteins that share weak sequence similarity with vertebrate P2X receptors. Unlike vertebrate P2X receptors, these proteins are not expressed on the surface of cells, but populate the tubules and bladders of the contractile vacuole. In this study, we expressed humanized cDNAs of P2XA, P2XB, P2XC, P2XD, and P2XE in human embryonic kidney cells and altered the ionic and proton environment in an attempt to reflect the situation in amoeba. Recording of whole-cell membrane currents showed that four receptors operated as ATP-gated channels (P2XA, P2XB, P2XD, and P2XE). At P2XA receptors, ATP was the only effective agonist of 17 structurally related putative ligands that were tested. Extracellular sodium, compared with potassium, strongly inhibited ATP responses in P2XB, P2XD, and P2XE receptors. Increasing the proton concentration (pH 6.2) accelerated desensitization at P2XA receptors and decreased currents at P2XD receptors, but increased the currents at P2XB and P2XE receptors. Dictyostelium lacking P2XA receptors showed impaired regulatory volume decrease in hypotonic solution. This phenotype was readily rescued by overexpression of P2XA and P2XD receptors, partially rescued by P2XB and P2XE receptors, and not rescued by P2XC receptors. The failure of the nonfunctional receptor P2XC to restore the regulatory volume decrease highlights the importance of ATP activation of P2X receptors for a normal response to hypo-osmotic shock, and the weak rescue by P2XB and P2XE receptors indicates that there is limited functional redundancy among Dictyostelium P2X receptors.


Assuntos
Dictyostelium/metabolismo , Proteínas de Protozoários/metabolismo , Receptores Purinérgicos P2X/metabolismo , Ácidos/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , Dictyostelium/citologia , Dictyostelium/efeitos dos fármacos , Espaço Extracelular/efeitos dos fármacos , Espaço Extracelular/metabolismo , Células HEK293 , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Ativação do Canal Iônico/efeitos dos fármacos , Íons/farmacologia , Ligantes , Fenótipo , Potássio/farmacologia , Soluções
10.
J Thorac Cardiovasc Surg ; 145(6): 1554-62, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22698566

RESUMO

OBJECTIVE: The feasibility of transapical valve-in-valve aortic valve implantation into a failed aortic surgical bioprosthesis has been confirmed. The purpose of the present study was to investigate the clinical and hemodynamic outcomes more than 2 years after transapical valve-in-valve aortic valve implantation. METHODS: From April 2007 to May 2010, 8 consecutive patients underwent transapical valve-in-valve aortic valve implantation of either 23- or 26-mm Edwards-SAPIEN balloon-expandable bioprostheses into failed surgical tissue valves (21- to 25-mm valves). Clinical and echocardiographic follow-up was performed in all patients. The mean follow-up duration was 27.8 ± 15.7 months (range, 18-55 months). RESULTS: Transapical valve-in-valve aortic valve implantation was successful in all patients (mean age, 84.1 ± 1.6 years). The predicted operative mortality was 42.1% ± 15.7% by logistic European System for Cardiac Operative Risk Evaluation and 14.4% ± 9.6% using the Society of Thoracic Surgeons risk calculator. The observed 30-day mortality was 12.5%. No strokes or valve embolization/migrations occurred. The mean hospital stay was 9.0 ± 9.1 days. The New York Heart Association class decreased from preoperative class III-IV to postoperative class I in 6 of 7 survivors. The 2-year survival was 87.5%. No late mortality occurred during the follow-up period. The echocardiographic results at 1 to 4 years of follow-up demonstrated stable valve position and function in all patients. The transaortic valve pressure gradients after valve-in-valve aortic valve implantation were greater than 20 mm Hg and less than 15 mm Hg in patients with 21- or 23-mm and 25-mm surgical valves, respectively. CONCLUSIONS: Transapical valve-in-valve aortic valve implantation provides good clinical outcomes and stable valve function beyond 2 years of follow-up. The best hemodynamic and clinical outcomes can be achieved in the patients with a surgical valve size of 25 mm or greater. Valve-in-valve aortic valve implantation could become a viable approach for selected high-risk patients with failed surgical bioprostheses.


Assuntos
Valva Aórtica/cirurgia , Bioprótese , Implante de Prótese de Valva Cardíaca/métodos , Próteses Valvulares Cardíacas , Idoso de 80 Anos ou mais , Valva Aórtica/diagnóstico por imagem , Ecocardiografia , Feminino , Seguimentos , Implante de Prótese de Valva Cardíaca/mortalidade , Humanos , Masculino , Complicações Pós-Operatórias , Reoperação/estatística & dados numéricos , Fatores de Tempo , Resultado do Tratamento
11.
JACC Cardiovasc Interv ; 5(5): 571-577, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22625197

RESUMO

OBJECTIVES: This study sought to evaluate outcomes after implantation of a second transcatheter heart valve (THV-in-THV) for acute THV failure. BACKGROUND: Aortic regurgitation after transcatheter aortic valve replacement (TAVR) may be valvular due to prosthetic leaflet dysfunction or paravalvular due to poor annular sealing. METHODS: Patients undergoing aortic balloon-expandable TAVR at 3 centers were prospectively evaluated at baseline, intraprocedurally, at hospital discharge, and annually. RESULTS: Of 760 patients undergoing TAVR, 21 (2.8%) received a THV-in-THV implant due to acute, severe regurgitation. Aortic regurgitation was paravalvular in 18 patients and transvalvular in the remaining 3 patients. THV-in-THV implantation was technically successful in 19 patients (90%) and unsuccessful in 2 patients (10%), who subsequently underwent open heart surgery. Mortality at 30 days and 1 year was 14.3% and 24%, respectively. After successful THV-in-THV, mean aortic valve gradient fell from 37 ± 12 mm Hg to 13 ± 5 mm Hg (p < 0.01); aortic valve area increased from 0.64 ± 0.14 cm(2) to 1.55 ± 0.27 cm(2) (p < 0.01); and paravalvular aortic regurgitation was none in 4 patients, mild in 13 patients, and moderate in 2 patients. At 1-year follow-up, 1 patient had moderate and the others had mild or no paravalvular leaks. The mean transvalvular gradient was 15 ± 4 mm Hg, which was higher than in patients undergoing conventional TAVR (11 ± 4 mm Hg, p = 0.02). CONCLUSIONS: THV-in-THV implantation is feasible and results in satisfactory short- and mid-term outcomes.


Assuntos
Insuficiência da Valva Aórtica/terapia , Estenose da Valva Aórtica/terapia , Cateterismo Cardíaco/instrumentação , Implante de Prótese de Valva Cardíaca/instrumentação , Implante de Prótese de Valva Cardíaca/métodos , Próteses Valvulares Cardíacas , Falha de Prótese , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Insuficiência da Valva Aórtica/diagnóstico , Insuficiência da Valva Aórtica/etiologia , Insuficiência da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/mortalidade , Canadá , Cateterismo Cardíaco/mortalidade , Distribuição de Qui-Quadrado , Ecocardiografia Doppler em Cores , Ecocardiografia Transesofagiana , Estudos de Viabilidade , Feminino , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/mortalidade , Humanos , Estimativa de Kaplan-Meier , Masculino , Ohio , Valor Preditivo dos Testes , Estudos Prospectivos , Desenho de Prótese , Retratamento , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Falha de Tratamento
12.
JACC Cardiovasc Interv ; 5(5): 582-590, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22625199

RESUMO

OBJECTIVES: This study sought to report on the pathology of transcatheter aortic valves explanted at early and late time points after transcatheter aortic valve implantation. BACKGROUND: Information on pathological findings following transcatheter aortic valve implantation is scarce, particularly late after transcatheter aortic valve implantation. METHODS: This study included 20 patients (13 men, median age 80 years [interquartile range: 72 to 84] years) with previous transcatheter aortic valve implantation with a valve explanted at autopsy (n = 17) or surgery (n = 3) up to 30 months after implantation (10 transapical and 10 transfemoral procedures). RESULTS: Structural valve degeneration was not seen, although fibrous tissue ingrowth was observed at later time points with minimal effects on cusp mobility in 1 case. Minor alterations in valve configuration or placement were observed in up to 50% of cases, but they were not accompanied by substantial changes in valve function or reliably associated with chest compressions. Vascular or myocardial injury was common, especially within 30 days of transcatheter aortic valve implantation (about 69%), with the latter associated with left coronary ostial occlusion by calcified native aortic valve tissue in 2 cases. Mild to severe myocardial amyloidosis was present in nearly 33% of cases and likely played a role in the poor outcome of 3 patients. Endocarditis, migration of the valve, and embolization during the procedure led to surgical valve removal. CONCLUSIONS: Structural degeneration was not seen and minor alterations of valve configuration or placement did not affect valve function and were not reliably caused by chest compressions. Vascular or myocardial injury is very common early after transcatheter aortic valve implantation and myocardial amyloidosis represents a relatively frequent potentially significant comorbid condition.


Assuntos
Estenose da Valva Aórtica/terapia , Cateterismo Cardíaco/efeitos adversos , Doenças Cardiovasculares/etiologia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Amiloidose/etiologia , Amiloidose/patologia , Valva Aórtica/patologia , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/mortalidade , Autopsia , Colúmbia Britânica , Cateterismo Cardíaco/mortalidade , Cardiomiopatias/etiologia , Cardiomiopatias/patologia , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/patologia , Doenças Cardiovasculares/cirurgia , Causas de Morte , Remoção de Dispositivo , Endocardite/etiologia , Endocardite/patologia , Feminino , Migração de Corpo Estranho/etiologia , Migração de Corpo Estranho/patologia , Implante de Prótese de Valva Cardíaca/métodos , Implante de Prótese de Valva Cardíaca/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Fatores de Tempo , Resultado do Tratamento
13.
J Am Coll Cardiol ; 59(23): 2068-74, 2012 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-22483326

RESUMO

OBJECTIVES: The aim of this study was to evaluate the impact of mitral regurgitation (MR) on outcomes after transcatheter aortic valve replacement (TAVR) and the impact of TAVR on MR. BACKGROUND: Little is known of the influence of MR on outcomes after TAVR. METHODS: The outcomes of patients with mild or less (n = 319), moderate (n = 89), and severe (n = 43) MR were evaluated after TAVR at 2 Canadian centers. RESULTS: Patients with moderate or severe MR had a higher mortality rate than those with mild or less MR during the 30 days after TAVR (adjusted hazard ratio: 2.10; 95% confidence interval: 1.12 to 3.94; p = 0.02). However, the mortality rates after 30 days were similar (adjusted hazard ratio: 0.82; 95% confidence interval: 0.50 to 1.34; p = 0.42). One year after TAVR, moderate MR had improved in 58%, remained moderate in 17%, and worsened to severe in 1%, and 24% of patients had died. Severe MR had improved in 49% and remained severe in 16%, and 35% of patients had died. Multivariate predictors of improved MR at 1 year (vs. unchanged MR, worse MR, or death) were a mean transaortic gradient ≥ 40 mm Hg, functional (as opposed to structural) MR, the absence of pulmonary hypertension, and the absence of atrial fibrillation. CONCLUSIONS: Moderate or severe MR in patients undergoing TAVR is associated with a higher early, but not late, mortality rate. At 1-year follow-up, MR was improved in 55% of patients with moderate or severe MR at baseline. Improvement was more likely in patients with high transaortic gradients, with functional MR, without pulmonary hypertension and without atrial fibrillation.


Assuntos
Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/terapia , Implante de Prótese de Valva Cardíaca/mortalidade , Implante de Prótese de Valva Cardíaca/métodos , Insuficiência da Valva Mitral/mortalidade , Insuficiência da Valva Mitral/terapia , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/diagnóstico por imagem , Bioprótese , Colúmbia Britânica , Cateterismo Cardíaco/métodos , Estudos de Coortes , Ecocardiografia Doppler , Feminino , Seguimentos , Próteses Valvulares Cardíacas , Humanos , Estimativa de Kaplan-Meier , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/mortalidade , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/diagnóstico por imagem , Razão de Chances , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Falha de Prótese , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
14.
Laryngoscope ; 122(2): 393-400, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22252464

RESUMO

OBJECTIVES/HYPOTHESIS: To describe the population of patients with malignancy affecting the ear canal and temporal bone. STUDY DESIGN: Retrospective review. METHODS: The charts of 157 patients with temporal bone cancer were reviewed for clinical outcomes. RESULTS: Between 1999 and 2009, 157 patients underwent temporal bone surgery for cancer involving the ear canal (n = 25), external ear with ear canal involvement (n = 26), periauricular skin (n = 40), parotid gland (n = 40), temporal bone (n = 13), and lateral skull base (n = 13). All surgeries involved one or more otologic approaches: mastoidectomy (28.0%), lateral temporal bone resection (TBR) (59.2%), subtotal TBR (2.5%), total TBR (3.2%), transtemporal approach (TTA) to the jugular foramen (8.2%), TTA to the middle fossa (5.7%), and TTA to the infratemporal fossa (3.2%). Cancers of the cartilaginous ear canal were managed with wide local excision of canal skin and cartilage in nine patients (5.7%). A combination of approaches was performed in 32 patients (20.4%). The 5-year overall survival rate was 58.0%. Patients whose disease was limited to the ear canal had significantly better overall survival than did patients who had skull base primaries (P = .02989), periauricular skin cancer (P = .00138), or temporal bone tumors (P = .02598). Patients with parotid tumors also had better overall survival than did those with periauricular skin tumors (P = .02357). CONCLUSIONS: Otologic surgery plays an important role in managing cancers that involve the ear canal, temporal bone, or lateral skull base. The specialty of otologic oncology is emerging as a defined area of practice.


Assuntos
Neoplasias da Orelha/epidemiologia , Base do Crânio , Neoplasias Cranianas/epidemiologia , Osso Temporal , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Neoplasias da Orelha/diagnóstico , Neoplasias da Orelha/cirurgia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Otolaringologia , Procedimentos Cirúrgicos Otológicos/métodos , Prognóstico , Estudos Retrospectivos , Neoplasias Cranianas/diagnóstico , Neoplasias Cranianas/cirurgia , Estados Unidos/epidemiologia , Adulto Jovem
15.
Laryngoscope ; 121(8): 1702-7, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21792957

RESUMO

OBJECTIVES/HYPOTHESIS: To describe the results of temporal bone surgery in managing advanced or recurrent tumors of the parotid gland. STUDY DESIGN: Retrospective review. METHODS: Patients with advanced or recurrent tumors involving the parotid gland who underwent either mastoidectomy or temporal bone resection were reviewed for treatment outcomes. RESULTS: Forty-nine patients were identified who required either mastoidectomy (n = 33) or temporal bone resection (n = 16) for malignancies involving the parotid gland. Facial nerve sacrifice was required in 35 patients (71.4%). Perineural invasion was found in 51.1% of patients; and negative margins were achieved in 78.2% patients. Six of 10 patients presenting with normal facial function (House-Brackmann I) and recurrent tumors maintained normal facial function following salvage surgery. Trismus, tumors larger than 4 cm, and the need for mandibulectomy were significantly correlated with higher recurrence rates (P = .025, P = .004, and P = .002, respectively). Patients with preoperative House-Brackmann I or II had a lower risk for recurrence (P = .035) and more favorable survival at 3 years (P = .024). Patients who required parapharyngeal space dissection and those with metastatic neck disease had the poorest survival rates. The overall survival at 3 years was 72.4%. CONCLUSIONS: Mastoidectomy and temporal bone resection permit preservation of the facial nerve when oncologically safe; they may help to achieve negative margins, and they allow facial nerve grafting when nerve sacrifice is required. Despite the poor prognostic indicators of facial paralysis, recurrent tumors, and perineural invasion, a significant number of patients can be salvaged successfully when a temporal bone procedure is combined with parotidectomy.


Assuntos
Recidiva Local de Neoplasia/cirurgia , Neoplasias Parotídeas/cirurgia , Osso Temporal/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Adjuvante , Nervo Facial/cirurgia , Feminino , Humanos , Masculino , Processo Mastoide/cirurgia , Pessoa de Meia-Idade , Neoplasias Parotídeas/patologia , Complicações Pós-Operatórias , Radioterapia Adjuvante , Adulto Jovem
16.
J Thorac Cardiovasc Surg ; 139(5): 1107-13, 1113.e1, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20412948

RESUMO

BACKGROUND: We performed the first human case of successful transapical transcatheter aortic valve implantation on a beating heart in October 2005, and therefore we have the longest follow-up on transapical aortic valve implantation in humans. We now report clinical and echocardiographic outcomes of transapical aortic valve implantation in 71 patients. METHODS: Between October 2005 and February 2009, 71 patients (44 female) underwent transcatheter transapical aortic valve implantation with either 23- or 26-mm Edwards Lifesciences transcatheter bioprostheses. All patients with symptomatic aortic stenosis were declined for conventional aortic valve replacement owing to unacceptable operative risks and were not candidates for transfemoral aortic valve implantation because of poor arterial access. Clinical and echocardiographic follow-ups were performed before discharge, at 1 and 6 months, and then yearly. The mean follow-up was 12.9 +/- 11.5 months with a total of 917.3 months of follow-up. RESULTS: Mean age was 80.0 +/- 8.1 years and predicted operative mortality was 34.5% +/- 20.4% by logistic EuroSCORE and 12.1% +/- 7.7% by The Society of Thoracic Surgeons Risk Calculator. Valves were successfully implanted in all patients. Twelve patients died within 30 days (30-day mortality: 16.9% in all patients, 33% in the first 15 patients, and 12.5% in the remainder), and 10 patients died subsequently. Overall survival at 24 and 36 months was 66.3% +/- 6.4% and 58.0% +/- 9.5%, respectively. Among 59 patients who survived at least 30 days, 24- and 36-month survivals were 79.8% +/- 6.4% and 69.8% +/- 10.9%, respectively. Late valve-related complications were rare. New York Heart Association functional class improved significantly from preoperative 3.3 +/- 0.8 to 1.8 +/- 0.8 at 24 months. The aortic valve area and mean gradient remained stable at 24 months (1.6 +/- 0.3 cm(2) and 10.3 +/- 5.9 mm Hg, respectively). CONCLUSION: Our outcome suggests that transapical transcatheter aortic valve implantation provides sustained clinical and hemodynamic benefits for up to 36 months in selected high-risk patients with symptomatic severe aortic stenosis.


Assuntos
Estenose da Valva Aórtica/terapia , Valva Aórtica , Cateterismo Cardíaco , Implante de Prótese de Valva Cardíaca/métodos , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/fisiopatologia , Bioprótese , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/instrumentação , Cateterismo Cardíaco/mortalidade , Feminino , Seguimentos , Próteses Valvulares Cardíacas , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/instrumentação , Implante de Prótese de Valva Cardíaca/mortalidade , Hemodinâmica , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Seleção de Pacientes , Desenho de Prótese , Recuperação de Função Fisiológica , Medição de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia
17.
Ann Thorac Surg ; 88(4): 1322-4, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19766829

RESUMO

Off-pump transcatheter, transapical valve-in-valve aortic valve implantation into a failed surgically implanted aortic valve was successfully performed in an 85-year-old man. He was discharged on postoperative day 5, and remained well at his 16-month follow-up. Echocardiography at 12 months showed normal prosthetic valve function without displacement, recoil, or regurgitation. Transcatheter transapical valve-in-valve aortic valve implantation is feasible and could be a viable approach for selected patients.


Assuntos
Insuficiência da Valva Aórtica/cirurgia , Cateterismo Cardíaco/instrumentação , Implante de Prótese de Valva Cardíaca/instrumentação , Idoso de 80 Anos ou mais , Insuficiência da Valva Aórtica/diagnóstico por imagem , Ecocardiografia , Desenho de Equipamento , Seguimentos , Humanos , Masculino , Radiografia Torácica , Fatores de Tempo
19.
Am J Cardiol ; 103(9): 1295-301, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19406275

RESUMO

Transcatheter aortic valve replacement (TAVR) required precise knowledge of the anatomic dimensions and physical characteristics of the aortic valve, annulus, and aortic root. Most groups currently use angiography, transthoracic echocardiography (TTE), or transesophageal echocardiography (TEE) to assess aortic annulus dimensions and anatomy. However, multislice computed tomography (MSCT) may allow more detailed 3-dimensional assessment of the aortic root. Twenty-six patients referred for TAVR underwent MSCT. Scans were also obtained for 18 patients after TAVR. All patients underwent pre- and postprocedural aortic root angiography, TTE, and TEE. Mean differences in measured aortic annular diameters were 1.1 mm (95% confidence interval 0.5, 1.8) for calibrated angiography and TTE, -0.9 mm (95% confidence interval -1.7, -0.1 mm) for TTE and TEE, -0.3 mm (95% confidence interval -1.1, 0.6 mm) for MSCT (sagittal) and TTE, and -1.2 mm (95% confidence interval -2.2, -0.2 mm) for MSCT (sagittal) and TEE. Coronal systolic measurements using MSCT, which corresponded to angiographic orientation, were 3.2 mm (1st and 3rd quartiles 2.6, 3.9) larger than sagittal systolic measurements, which were in the same anatomic plane as standard TTE and TEE views. There was no significant association between either shape of the aortic annulus or amount of aortic valve calcium and development of perivalvular aortic regurgitation. After TAVR, the prosthesis extended to or beyond the inferior border of the left main ostium in 9 of 18 patients (50%), and in 11 patients (61%), valvular calcium was <5 mm from the left main ostium. In conclusion, MSCT identified that the aortic annulus was commonly eccentric and often oval. This may in part explain the small, but clinically insignificant, differences in measured aortic annular diameters with other imaging modalities. MSCT after TAVR showed close proximity of both the prosthesis and displaced valvular calcium to the left main ostium in most patients. Neither eccentricity nor calcific deposits appeared to contribute significantly to severity of paravalvular regurgitation after TAVR.


Assuntos
Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Imageamento Tridimensional/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Cateterismo Cardíaco/métodos , Estudos de Coortes , Ecocardiografia/métodos , Ecocardiografia Transesofagiana/métodos , Feminino , Seguimentos , Doenças das Valvas Cardíacas/diagnóstico , Doenças das Valvas Cardíacas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Medição de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Resultado do Tratamento
20.
J Thorac Cardiovasc Surg ; 137(1): 167-73, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19154921

RESUMO

BACKGROUND: We reported the first case of successful transapical transcatheter aortic valve implantation in a human subject in 2005 and have now completed a 12-month follow-up on our first 26 patients. This is, to date, the longest follow-up of patients undergoing transapical aortic valve implantation. METHODS: Between October 2005 and January 2007, 26 patients (13 female) underwent transcatheter transapical aortic valve implantation with either 23- or 26-mm Edwards Lifesciences transcatheter bioprostheses. All patients with symptomatic aortic stenosis were declined for conventional aortic valve replacement because of unacceptable operative risks and were not candidates for transfemoral aortic valve implantation because of poor arterial access. Clinical and echocardiographic follow-up was performed before discharge and at 1, 6, and 12 months. Data from the 17 patients who survived over 12 months were used for comparisons of the baseline and follow-up results. RESULTS: The mean age was 80 +/- 9 years, and the predicted operative mortality was 37% +/- 20% by using logistic EuroSCORE and 11% +/- 6% by using the Society of Thoracic Surgeons Risk Calculator. Valves were successfully implanted in all patients. Six patients died within 30 days (30-day mortality, 23%), and 3 patients died from noncardiovascular causes after 30 days (late mortality, 12%). Among patients who survived at least 30 days, 12-month survival was 85%. There were no late valve-related complications. New York Heart Association functional class improved significantly. The aortic valve area and mean gradient remained stable at 12 months (1.6 +/- 0.3 cm(2) and 9.6 +/- 4.8 mm Hg, respectively). CONCLUSION: Our 1-year clinical and echocardiographic outcomes suggest that transapical transcatheter aortic valve implantation is a viable alternative to conventional aortic valve replacement in selected high-risk patients.


Assuntos
Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/diagnóstico por imagem , Cateterismo Cardíaco , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia
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