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2.
J Robot Surg ; 18(1): 16, 2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38217749

RESUMO

Robotic assisted surgery (RAS) has seen a global rise in adoption. Despite this, there is not a standardised training curricula nor a standardised measure of performance. We performed a systematic review across the surgical specialties in RAS and evaluated tools used to assess surgeons' technical performance. Using the PRISMA 2020 guidelines, Pubmed, Embase and the Cochrane Library were searched systematically for full texts published on or after January 2020-January 2022. Observational studies and RCTs were included; review articles and systematic reviews were excluded. The papers' quality and bias score were assessed using the Newcastle Ottawa Score for the observational studies and Cochrane Risk Tool for the RCTs. The initial search yielded 1189 papers of which 72 fit the eligibility criteria. 27 unique performance metrics were identified. Global assessments were the most common tool of assessment (n = 13); the most used was GEARS (Global Evaluative Assessment of Robotic Skills). 11 metrics (42%) were objective tools of performance. Automated performance metrics (APMs) were the most widely used objective metrics whilst the remaining (n = 15, 58%) were subjective. The results demonstrate variation in tools used to assess technical performance in RAS. A large proportion of the metrics are subjective measures which increases the risk of bias amongst users. A standardised objective metric which measures all domains of technical performance from global to cognitive is required. The metric should be applicable to all RAS procedures and easily implementable. Automated performance metrics (APMs) have demonstrated promise in their wide use of accurate measures.


Assuntos
Procedimentos Cirúrgicos Robóticos , Robótica , Cirurgiões , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Robótica/educação , Currículo , Cirurgiões/educação , Competência Clínica
3.
Ann Dermatol Venereol ; 138(11): 739-42, 2011 Nov.
Artigo em Francês | MEDLINE | ID: mdl-22078034

RESUMO

BACKGROUND: Types of subepidermal autoimmune bullous dermatosis (AIBD) are classified by anatomoclinical picture and target antigen. A new entity has recently been identified: anti-p200 pemphigoid. PATIENTS AND METHODS: An 82-year-old man consulted for a profuse pruritic bullous eruption refractory to the standard treatments for bullous pemphigoid (BP). Direct immunofluorescence examination of a skin biopsy revealed linear deposits of IgG and of C3 at the dermal-epidermal junction, but Elisa screening for circulating anti-BP180 and anti-BP230 antibodies was negative. Indirect immunofluorescence (IIF) testing of cleaved skin revealed a deposit of IgG4 antibodies on the dermal side. Immunoblotting was negative for a dermal extract but showed an antibody directed against a 200-kD epidermal antigen. A diagnosis of anti-p200 pemphigoid was eventually made and the patient was successfully treated with dapsone. DISCUSSION: The diagnosis of anti-p200 pemphigoid was made in this case in spite of discrepancy between the IIF and immunoblotting results, and despite the fact that the target antigen in this disease is considered as being restricted to dermal sites. Anti-p200 pemphigoid usually begins in the second part of life and differs from standard bullous pemphigoid in terms of more frequent mucous membrane and cephalic involvement, as well as a greater degree of miliary scarring. This disease appears more prominent in males and is associated with psoriasis in around one third of cases. Autoantibodies recognize laminin gamma-1, an extra-desmosomal protein that contributes to dermal-epidermal adhesion. CONCLUSION: This recently described disease as probably under-diagnosed in France. It should be considered in atypical presentations of bullous disease. Diagnosis is confirmed by immunoblotting detection of autoantibodies directed against a 200-kD antigen normally present in the extract. Dapsone appears to be the most effective treatment.


Assuntos
Autoanticorpos/imunologia , Autoantígenos/imunologia , Dapsona/uso terapêutico , Laminina/imunologia , Penfigoide Bolhoso/tratamento farmacológico , Idoso de 80 Anos ou mais , Especificidade de Anticorpos , Clobetasol/uso terapêutico , Complemento C3/imunologia , Epiderme/imunologia , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imunoglobulina G/imunologia , Imunossupressores/uso terapêutico , Masculino , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapêutico , Penfigoide Bolhoso/diagnóstico , Penfigoide Bolhoso/imunologia , Prednisona/uso terapêutico
5.
Circ Res ; 98(4): 557-63, 2006 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-16439693

RESUMO

Occlusive vascular disease is a widespread abnormality leading to lethal or debilitating outcomes such as myocardial infarction and stroke. It is part of atherosclerosis and is evoked by clinical procedures including angioplasty and grafting of saphenous vein in bypass surgery. A causative factor is the switch in smooth muscle cells to an invasive and proliferative mode, leading to neointimal hyperplasia. Here we reveal the importance to this process of TRPC1, a homolog of Drosophila transient receptor potential. Using 2 different in vivo models of vascular injury in rodents we show hyperplasic smooth muscle cells have upregulated TRPC1 associated with enhanced calcium entry and cell cycle activity. Neointimal smooth muscle cells after balloon angioplasty of pig coronary artery also express TRPC1. Furthermore, human vein samples obtained during coronary artery bypass graft surgery commonly exhibit an intimal structure containing smooth muscle cells that expressed more TRPC1 than the medial layer cells. Veins were organ cultured to allow growth of neointimal smooth muscle cells over a 2-week period. To explore the functional relevance of TRPC1, we used a specific E3-targeted antibody to TRPC1 and chemical blocker 2-aminoethoxydiphenyl borate. Both agents significantly reduced neointimal growth in human vein, as well as calcium entry and proliferation of smooth muscle cells in culture. The data suggest upregulated TRPC1 is a general feature of smooth muscle cells in occlusive vascular disease and that TRPC1 inhibitors have potential as protective agents against human vascular failure.


Assuntos
Canais de Cátion TRPC/fisiologia , Túnica Íntima/patologia , Doenças Vasculares/metabolismo , Animais , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Humanos , Hiperplasia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/patologia , Ratos , Ratos Endogâmicos WKY , Veia Safena/patologia , Suínos , Canais de Cátion TRPC/antagonistas & inibidores , Canais de Cátion TRPC/genética , Regulação para Cima , Doenças Vasculares/tratamento farmacológico
6.
Heart ; 92(7): 939-44, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16251225

RESUMO

OBJECTIVES: To define best practice standards for mitral valve repair surgery. DESIGN: Development of standards for process and outcome by consensus. SETTING: Multidisciplinary panel of surgeons, anaesthetists, and cardiologists with interests and expertise in caring for patients with severe mitral regurgitation. MAIN OUTCOME MEASURES: Standards for best practice were defined including the full spectrum of multidisciplinary aspects of care. RESULTS: 19 criteria for best practice were defined including recommendations on surgical training, intraoperative transoesophageal echocardiography, surgery for atrial fibrillation, audit, and cardiology and imaging issues. CONCLUSIONS: Standards for best practice in mitral valve repair were defined by multidisciplinary consensus. This study gives centres undertaking mitral valve repair an opportunity to benchmark their care against agreed standards that are challenging but achievable. Working towards these standards should act as a stimulus towards improvements in care.


Assuntos
Insuficiência da Valva Mitral/cirurgia , Prática Profissional/normas , Fibrilação Atrial/cirurgia , Cardiologia/educação , Cardiologia/normas , Consultores , Ecocardiografia Transesofagiana , Educação Médica Continuada , Cirurgia Geral/educação , Cirurgia Geral/normas , Hospitais/normas , Hospitais/estatística & dados numéricos , Humanos , Cuidados Intraoperatórios , Auditoria Médica , Corpo Clínico Hospitalar/normas , Corpo Clínico Hospitalar/estatística & dados numéricos , Equipe de Assistência ao Paciente , Padrões de Referência , Procedimentos Cirúrgicos Torácicos/normas , Procedimentos Cirúrgicos Torácicos/estatística & dados numéricos , Reino Unido
7.
Cardiovasc Surg ; 9(4): 378-82, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11420163

RESUMO

This study was designed to measure the degree to which hand and forearm blood flow is reduced following harvesting of the radial artery in myocardial revascularization surgery and determine whether there is an effect on hand function. Twenty patients who had the radial artery used for myocardial revascularization underwent bilateral blood flow assessment of hands and forearms using Technetium-99m human serum albumin and clinical evaluation of hand function. Mean tissue perfusion in ml/100 ml/min +/- SD was as follows: donor hand 21.9 +/- 5.6, non-donor hand 25.5 +/- 6.1 (P = 0.00043), donor arm (hand and forearm) 17.5 +/- 3.7 and non-donor arm (hand and forearm) 21 +/- 5.1 (P = 0.000681). No clinical evidence of hand claudication was detected. This study suggests that removal of the radial artery reduces the tissue perfusion of the hand and forearm but does not affect hand function in the short term. The use of radial artery grafts in patients at risk of developing peripheral vascular disease should be carefully considered


Assuntos
Ponte de Artéria Coronária , Antebraço/irrigação sanguínea , Mãos/irrigação sanguínea , Isquemia/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Artéria Radial/transplante , Coleta de Tecidos e Órgãos , Adulto , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Feminino , Seguimentos , Força da Mão/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Fluxo Sanguíneo Regional/fisiologia , Agregado de Albumina Marcado com Tecnécio Tc 99m
8.
Br J Pharmacol ; 132(1): 302-8, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11156590

RESUMO

1. Vasospasm of arterial conduits used for coronary artery surgery is an important cause of graft failure and is likely to result partly from raised levels of vasoconstrictor substances such as thromboxane A(2) and endothelin-1. Our aim was to find pharmacological agents that could prevent agonist-induced vasospasm. 2. Isometric tension was recorded from discarded segments of human left internal mammary artery (LIMA). Submaximal contraction evoked by the thromboxane A(2) mimetic U46619 (10 nM) was not inhibited by a blocker of store- and receptor-operated Ca(2+) channels (30 microM SKF96365) in the presence of diltiazem. Furthermore, contractions to < or =1 nM U46619 were preserved when extracellular Ca(2+) was reduced from 2.5 mM to 60 nM. Thus, sustained U46619-evoked contraction occurred without Ca(2+) influx. 3., We hypothesized that contraction might occur via Rho-kinase-mediated Ca(2+)-sensitization of myofilaments. Inhibitors of Rho-kinase (Y27632 and HA1077) were profound relaxants. If contraction was pre-evoked by 10 nM U46619, Y27632 and HA1077 caused full relaxation with EC(50)s of 1.67+/-0.22 microM and 3.58+/-0.35 microM respectively. Y27632 was also effective if applied before U46619, but was less potent. 4. Y27632 abolished contraction evoked by endothelin-1 and significantly reduced resting tone in the absence of a vasoconstrictor. 5. Rho-kinase-mediated Ca(2+)-sensitization appears to be a major mechanism of vasoconstriction in human LIMA. Rho-kinase inhibitors may have an important role in preventing vasospasm in arterial grafts used for coronary artery surgery.


Assuntos
Inibidores Enzimáticos/farmacologia , Artéria Torácica Interna/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Vasoconstrição/efeitos dos fármacos , Cálcio/metabolismo , Canais de Cálcio Tipo L/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Endotélio Vascular/fisiologia , Feminino , Humanos , Técnicas In Vitro , Peptídeos e Proteínas de Sinalização Intracelular , Contração Isométrica/efeitos dos fármacos , Artéria Torácica Interna/fisiologia , Contração Muscular/efeitos dos fármacos , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso Vascular/fisiologia , Quinases Associadas a rho
9.
Perfusion ; 15(3): 251-5, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10866428

RESUMO

Although Jehovah's Witnesses present a particular problem when undergoing surgery because of their refusal to accept stored blood, it is now quite common to undertake uncomplicated cardiac surgery in these patients. Complex or redo cardiac surgery however, is often associated with major blood loss, and is conventionally contraindicated in Jehovah's Witnesses. We describe the perioperative management of a Jehovah's Witness who underwent a resternotomy for mitral valve replacement and coronary artery bypass grafting having previously had an aortic valve replacement and mitral valve repair. The importance of a multidisciplinary approach to blood conservation is discussed.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Procedimentos Cirúrgicos Cardíacos/métodos , Cristianismo , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/psicologia , Cristianismo/psicologia , Ponte de Artéria Coronária , Feminino , Implante de Prótese de Valva Cardíaca , Humanos , Pessoa de Meia-Idade , Valva Mitral/cirurgia , Religião e Medicina
10.
Eur J Cardiothorac Surg ; 17(3): 319-24, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10758394

RESUMO

OBJECTIVE: The radial artery is becoming popular as a conduit for coronary artery surgery but there is concern about its tendency to vasospasm. Diltiazem is used clinically in an effort to prevent vasospasm but there are suggestions that it is relatively ineffective. The first aim of the study was to test the effectiveness of Ca(2+) antagonists against vasospasm evoked by vasoconstrictor agonists. Because a large component of vasospasm was resistant to Ca(2+) antagonists, the second aim was to test if a different class of vasodilator, nicorandil, might relax the residual tone. METHODS: Isometric tension was recorded in human radial artery segments harvested from patients undergoing myocardial revascularization surgery. RESULTS: Diltiazem at 10 microM, which strongly inhibits L-type voltage-gated Ca(2+) channels, induced partial relaxation (mean+/-SEM, 44.6+/-3.5%, n=31) of phenylephrine-evoked contraction, but only 14.0+/-4.1% (n=10) and 12. 2+/-4.2% (n=10) relaxation of U46619- (a thromboxane A(2) analogue) or endothelin-1-evoked contraction. Strikingly, nicorandil relaxed agonist-evoked contractions that were resistant to diltiazem or nicardipine. In the absence of a Ca(2+) antagonist, nicorandil (30 microM) evoked 74.1+/-5.6% (n=24), 36.8+/-9.3% (n=10) and 64.5+/-7. 9% (n=14) relaxation of phenylephrine-, U46619- and endothelin-1-evoked contractions. CONCLUSIONS: Nicorandil has a marked relaxant effect on contractions evoked by three different vasoconstrictor agonists, and relaxes vasospasm that is resistant to conventional Ca(2+) antagonists. These in vitro data suggest that nicorandil might be a useful drug for the inhibition of radial artery vasospasm in myocardial revascularization surgery.


Assuntos
Nicorandil/farmacologia , Artéria Radial/fisiologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Humanos , Artéria Radial/efeitos dos fármacos
11.
Heart ; 83(4): E6, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10722558

RESUMO

A case is reported of a 59 year old woman who presented with palpitations. Electrocardiographic studies revealed atrial fibrillation and atrioventricular block. Echocardiography and magnetic resonance imaging showed a right atrial cystic mass attached to the interatrial septum. The patient underwent surgical excision of the mass. Histopathological findings were of a cystic tumour of the atrioventricular nodal region. This is the second report of this condition diagnosed antemortem and treated successfully with surgical excision.


Assuntos
Arritmias Cardíacas/etiologia , Nó Atrioventricular , Bloqueio Cardíaco/etiologia , Neoplasias Cardíacas/cirurgia , Mesotelioma/cirurgia , Eletrocardiografia , Feminino , Neoplasias Cardíacas/patologia , Humanos , Mesotelioma/patologia , Pessoa de Meia-Idade
12.
Perfusion ; 14(1): 3-10, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10074641

RESUMO

Cardiopulmonary bypass (CPB) involves the use of either an occlusive roller pump or centrifugal pump. Damage to blood elements, including haemolysis, may arise from occlusion when using a roller pump; the appropriate degree of occlusion has not yet been determined scientifically. Centrifugal and nonocclusive roller pumps are reputed to reduce haemolysis. The objective of this study was to compare haemolysis caused by a standard roller pump with a dynamically set nonocclusive roller pump and with a centrifugal pump. We prospectively randomized 60 patients undergoing routine coronary artery surgery into three groups: standard roller pump (STD, n = 20), dynamically set roller pump (DYN, n = 20), or centrifugal pump (CEN, n = 20). The level of plasma free haemoglobin (FHb) was measured preoperatively, and the rate of formation of FHb (in mg/dl/min) was determined at the end of the ischaemic phase and at the end of CPB. Cardiotomy suction blood was isolated for the ischaemic phase and returned before the end of CPB. It was found that there were no differences between the groups in demographic or operative variables. The rate of formation of FHb at the end of the ischaemic phase was similar for all groups (STD 0.108 +/- 0.10, DYN 0.117 +/- 0.08, CEN 0.129 +/- 0.07). At the end of CPB, after return of the cardiotomy suction blood, there was a significant (< 0.001) increase in the rate of formation of FHb in all groups. The increase was similar for each of the groups (STD 0.424 +/- 0.17, DYN 0.481 +/- 0.20, CEN 0.471 +/- 0.18). We conclude that the rates of haemolysis are similar for each of the pump types, and no benefit is conferred by the use of either a dynamically set roller pump or a centrifugal pump compared with the standard roller pump. The return of the cardiotomy suction blood to the circulation is the principal source of plasma free haemoglobin.


Assuntos
Ponte de Artéria Coronária/instrumentação , Ponte de Artéria Coronária/métodos , Máquina Coração-Pulmão , Hemólise , Idoso , Desenho de Equipamento , Contagem de Eritrócitos , Feminino , Hematócrito , Hemoglobinas/análise , Humanos , Período Intraoperatório , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas
13.
Perfusion ; 14(1): 29-36, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10074644

RESUMO

Liver blood flow is reduced after cardiopulmonary bypass (CPB) and both dopamine and dopexamine are used to overcome this. This study compares the effects of these agents on liver blood flow. Thirty patients undergoing elective coronary artery bypass graft surgery were randomized into three groups (n = 10 per group). Six hours after surgery baseline liver blood flow was determined by the percentage disappearance rate of indocyanine green measured by dichromatic auricular densitometery. Patients then received infusions of either: (1) placebo (dextrose 5%); (2) dopamine (4 micrograms/kg/min); (3) dopexamine (1 microgram/kg/min increasing to 2 micrograms/kg/min). One hour after infusion, liver blood flow measurements were repeated. In the dopexamine group the infusion was increased and the measurements repeated another hour later. We found that patient-specific variables and operative details were similar for all groups. Postoperative cardiac index and heart rate were increased significantly by dopamine (cardiac index 2.82 +/- 0.46 l/m/m2 vs 3.28 +/- 0.67 l/m/m2: p < 0.001 and heart rate 87.5 +/- 13.2 vs 96 +/- 16: p < 0.05) and dopexamine at 2 micrograms/kg/min (cardiac index 2.71 +/- 0.53 l/m/m2 vs 3.45 +/- 0.67 l/m/m2: p < 0.05 and heart rate 89.0 +/- 18.9 vs 107.4 +/- 13.6: p < 0.001) compared to placebo (cardiac index 2.97 +/- 0.8 l/m/m2 vs 3.18 +/- 0.9 l/m/m2: p > 0.05 and heart rate 77.2 +/- 7.4 vs 77.3 +/- 8: p > 0.05) despite similar atrial and systemic arterial pressures. The disappearance rate of indocyanine green was not altered during infusion of placebo group (9.0 +/- 3.2%/min vs 7.9 +/- 3.0%/min: p > 0.05) or dopexamine at 1 microgram/kg/min (9.7 +/- 3.1%/min vs 11.2 +/- 4.1%/min: p > 0.05). The disappearance rate was increased with dopamine (6.7 +/- 3.7%/min vs 11.8 +/- 3.0%/min: p < 0.05) and dopexamine 2 micrograms/kg/min (9.7 +/- 3.1%/min vs 13.5 +/- 3.2%/min: p < 0.05). This indicates a 76% increase in liver blood flow with dopamine and a 38% increase with dopexamine. We conclude that dopamine 4 micrograms/kg/min and dopexamine 2 micrograms/kg/min increase liver blood flow, although this may, in part, be related to an increase in cardiac output. Dopexamine shows no advantage over dopamine in enhancing liver blood flow after CPB.


Assuntos
Ponte de Artéria Coronária , Agonistas de Dopamina/uso terapêutico , Dopamina/análogos & derivados , Dopamina/uso terapêutico , Circulação Hepática/efeitos dos fármacos , Idoso , Débito Cardíaco/efeitos dos fármacos , Corantes/farmacocinética , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Verde de Indocianina/farmacocinética , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Resultado do Tratamento , Resistência Vascular/efeitos dos fármacos
14.
Angiogenesis ; 2(3): 265-75, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-14517466

RESUMO

Tumor necrosis factor-alpha (TNF-alpha) and fibroblast growth factor-2 (FGF-2 or bFGF) are potent stimulators of angiogenesis. TNF- alpha, but not FGF-2, can induce the expression of vascular cell adhesion molecule-1 (VCAM-1) on the surface of endothelial cells. The soluble form of VCAM-1 has recently been demonstrated to function as an angiogenic mediator. Here we demonstrate that monoclonal antibodies directed against VCAM-1 or its alpha4 integrin counter- receptor inhibited TNF-alpha-induced endothelial cell migration in vitro. Angiogenesis induced in vivo in rat corneas by TNF-alpha was inhibited by a neutralizing antibody directed against the rat alpha4 integrin subunit. A peptide antagonist of the a4 integrins blocked TNF-alpha-induced endothelial cell migration in vitro and angiogenesis in rat corneas in vivo. No inhibition by the antibodies or peptide antagonist was observed either in vitro or in vivo when FGF-2 was used as the stimulus. The peptide antagonist did not inhibit TNF-a binding to its receptor nor did it block the function of alphavbeta3, an integrin previously implicated in TNF-a and FGF- 2 mediated angiogenesis. These results demonstrate that angiogenic processes induced by TNF-alpha are mediated in part by agr;4 integrins possibly by a mechanism involving the induction of soluble VCAM-1.

16.
Ann Thorac Surg ; 57(2): 371-5, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8311598

RESUMO

Gastric mucosal tonometry was used to determine the adequacy of gastrointestinal perfusion in 10 patients undergoing elective myocardial revascularization. Patients were prospectively randomized to receive either pulsatile or nonpulsatile flow during cardiopulmonary bypass. All patients showed a reduction in gastric mucosal perfusion during bypass, manifested by a reduction in the gastric mucosal pH, which occurred independently of variations in the arterial pH. In the group of patients receiving nonpulsatile flow, this reduction was significantly greater (p < 0.05). Cardiopulmonary bypass using nonpulsatile flow is associated with the development of a gastric mucosal acidosis, which may have implications for the development of postoperative complications.


Assuntos
Ponte Cardiopulmonar/métodos , Mucosa Gástrica/irrigação sanguínea , Acidose/sangue , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fluxo Pulsátil , Fluxo Sanguíneo Regional
17.
Int J Biochem ; 25(2): 163-82, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8444313

RESUMO

1. Adenine nucleotide concentrations in normal and one day hypertrophied hearts of untreated, orotic acid (OA), uridine, uracil, dihydroorotate and reserpine pretreated rats were measured. OA treatment increased the ADP concentration 5-fold in one day hypertrophied hearts. Neither uracil, uridine, dihydroorotate nor reserpine treatments changed ADP or total adenylate concentrations at one day of hypertrophy. 2. The adenine nucleotide ratio (ANR) at 0.263 x 10(3) M-1 and the energy charge (0.66) were at their lowest values in OA and in reserpine treated one day hypertrophying hearts. The temporal decline in the indices of energy metabolism corresponded with the OA induced maximum stimulation of contractility and maximum rates of protein, RNA and glycogen synthesis. 3. The phosphorylation state of the adenine nucleotides (PSAN) was both the most sensitive and the best predictive index of the cellular energy status in normal and hypertrophying hearts. The pronounced ability of OA treatment to energize myocyte cytoplasm was shown by the 9- and 6-fold greater values of PSAN over ANR in one and three day hypertrophied hearts. The enhanced PSAN may be the key factor in the mechanism of OA induced enhancement of contractile and synthetic functions of the heart in compensatory hypertrophy. 4. The development of myocardial hypertrophy in untreated rats resulted in a 36% reduction in the cytoplasmic NAD/NADH ratio. In rats treated with OA this redox couple of the hypertrophying heart was more oxidized and was increased by 30% to restore it to the value range of normal heart. 5. The regulatory status of the glycolytic pathway in untreated and OA treated hypertrophying hearts was assessed by comparisons of the mass action ratio (MAR) and equilibrium constants for each of the individual glycolytic reactions. There was an OA induced 2.7-fold increase in glycogen, UDP-glucose and total uridine nucleotides in hypertrophied hearts. The concentrations of seven out of ten glycolytic intermediates, including pyruvate and lactate were increased as a consequence of OA treated hypertrophy. Glycolytic flux was not stalled, rather the pathway was "more open" permitting greater throughput of intermediates with individually increased levels of selected metabolites. OA stimulated hypertrophy did not change the canonical control of glycolysis by the activities and individual MAR values of phosphofructokinase and pyruvic kinase. 6. Elevated levels of Glu 6-P, Fru 6-P and DHAP can force glycolytic intermediate entry into the non-oxidative reaction segment of the pentose pathway (PP), thereby elevating Rib 5-P concentration by reversal of the conventional flux direction of PP.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Metabolismo dos Carboidratos , Cardiomegalia/metabolismo , Metabolismo Energético/efeitos dos fármacos , Ácido Orótico/farmacologia , Difosfato de Adenosina/metabolismo , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Glicólise , Coração/efeitos dos fármacos , Masculino , Miocárdio/metabolismo , NAD/metabolismo , Oxirredução , Fosforilação , Ratos , Ratos Wistar , Reserpina/farmacologia , Termodinâmica
18.
Eur J Cardiothorac Surg ; 7(6): 306-11; discussion 312, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8347356

RESUMO

We have reviewed the outcome in a consecutive series of 254 patients over the age of 70 undergoing cardiac surgery between 1987-89. Of the patients, 62% were male and the median age was 73 years. Operations included: coronary bypass 57%, valve replacement 26%, combinations 14% and other procedures 3%. The hospital mortality was 7.5% and late mortality was 13.8%. Complications included: intraaortic balloon 6%, resternotomy for bleeding 4%, permanent pacing 3%, chest infection 14%, tracheostomy 5%, major cerebrovascular events 3% and minor 4%. Eighty-two percent left the intensive care unit within 24 h and 89% left hospital within 8 days. Two questionnaires (York University) were sent to 207 patients believed to be alive in order to evaluate the change in their quality of life following surgery. Of the 207 questionnaires 197 (95%) were returned, 7 of which were from relatives of patients who had died and 7 were incomplete. The responses of 183 assessable patients (at a mean follow-up of 36 months) were converted into Rosser disability (I-VIII) and distress (A-D) groups. There was a decrease in disability and distress in 60% and 67%, respectively, no change in 34% and 30% and deterioration in 6% and 3%. Cardiac surgery can be carried out in elderly patients with an acceptable early morbidity and mortality, and although many patients show sustained improvement in their quality of life, this was not demonstrated in about a third of patients. As the emphasis in the elderly should be on quality of life we ought to continue to concentrate on careful selection in this age group.


Assuntos
Ponte de Artéria Coronária , Doença das Coronárias/cirurgia , Avaliação da Deficiência , Doenças das Valvas Cardíacas/cirurgia , Próteses Valvulares Cardíacas , Complicações Pós-Operatórias/etiologia , Qualidade de Vida , Idoso , Idoso de 80 Anos ou mais , Doença das Coronárias/mortalidade , Feminino , Doenças das Valvas Cardíacas/mortalidade , Humanos , Masculino , Complicações Pós-Operatórias/mortalidade , Estudos Retrospectivos
19.
Br Heart J ; 67(6): 504-5, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1377923

RESUMO

Emergency cardiac surgery after recent thrombolytic therapy is associated with increased blood loss. A patient underwent emergency repair of a ruptured left ventricle after intravenous streptokinase treatment for acute coronary occlusion. High dose aprotinin was given during the operation to reduce the expected blood loss. Surgical repair was successful without bleeding complications. Total postoperative blood loss was 365 ml.


Assuntos
Aprotinina/uso terapêutico , Perda Sanguínea Cirúrgica/prevenção & controle , Ruptura Cardíaca Pós-Infarto/cirurgia , Terapia Trombolítica/efeitos adversos , Idoso , Emergências , Feminino , Ruptura Cardíaca Pós-Infarto/etiologia , Humanos , Estreptoquinase/efeitos adversos
20.
Eur J Cardiothorac Surg ; 6(4): 201-8, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1586495

RESUMO

Twenty-six calves were subjected to a technique of cryoablation in order to establish an animal model of complete cardiac denervation. All 26 survived the procedure, and 20 were alive to be re-evaluated 2-4 weeks later. Mean heart rate in the denervated animals rose from 77 +/- 7.8 beats/min to 102 +/- 16.4 (P less than 0.01). Cryoablation abolished the heart rate responses to electrical stimulation of the vagus nerve and thoracic sympathetic trunk. The reduction in myocardial noradrenaline concentrations averaged 99% in the right atrium, 90% in the left atrium, 85% in the right ventricle and 90% in the left ventricle, when compared with tissue obtained from control animals. Cryoablation is a relatively simple means of accomplishing complete functional cardiac denervation in the calf. On the basis of the observed change in heart rate, the calf model appears to be more comparable with human heart transplant recipients than the dog.


Assuntos
Catecolaminas/metabolismo , Criocirurgia , Denervação/métodos , Coração/inervação , Coração/fisiopatologia , Miocárdio/metabolismo , Animais , Pressão Sanguínea , Bovinos , Estimulação Elétrica , Feminino , Frequência Cardíaca , Masculino , Sistema Nervoso Simpático/fisiologia , Sistema Nervoso Simpático/cirurgia , Nervo Vago/fisiologia , Nervo Vago/cirurgia
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