RESUMO
BACKGROUND: Natural orifice specimen extraction (NOSE) has been developed as a means of decreasing the incidence of surgical wound complications. We refined the procedure for totally laparoscopic colectomy with transvaginal specimen extraction using the reduced port surgery technique with the ultimate goal of attenuating damage to the abdominal wall. We herein report this innovative technique and its short- and long-term outcomes. METHODS: We prospectively collected data on seven patients who underwent totally laparoscopic colectomy using transvaginal specimen extraction with a 10-mm-long abdominal incision for right-sided colon cancer from January 2014 to December 2021. Two 5-mm ports were used in the procedure without laparotomy. Transverse transabdominal posterior colpotomy was then performed. We introduced a GelPOINT Mini advanced access platform (Applied Medical, Rancho Santa Margarita, CA, USA) into the transvaginal route for the insertion of a laparoscope, forceps, and stapling device. Lymph node dissection and transection of the ileum and distal colon were performed with transvaginal assistance. A specimen was then extracted transvaginally. Intracorporeal functional end-to-end anastomosis was conducted using a linear stapler through the vagina. After the removal of GelPOINT Mini, the vaginal incision was closed transvaginally. RESULTS: Seven patients successfully underwent this procedure. Median operative time was 219 min (range 174-255 min), median blood loss was 23 ml (range 10-37 ml), median number of harvested lymph nodes was 21 (range 17-35 lymph nodes) and median margins were 17.0 cm (range 9.0-25.0 cm) for the proximal margin and 9.5 cm (range 5.0-13.0 cm) for the distal margin. There were no complications more severe than Clavien-Dindo Grade II and there was no mortality. The median frequency of use intravenous analgesics from postoperative day 1 to discharge was once. Two patients did not require analgesics. A node-positive patient developed recurrence at the lung and paraaortic lymph nodes. CONCLUSIONS: This procedure appears to be feasible, safe, and oncologically acceptable for selected cases.
Assuntos
Neoplasias do Colo , Laparoscopia , Colectomia/métodos , Neoplasias do Colo/cirurgia , Feminino , Humanos , Laparoscópios , Laparoscopia/métodosRESUMO
The beta-catenin/TCF signaling pathway is essential for the maintenance of epithelial stem cells in the small intestine. c-Myc a downstream target of beta-catenin/TCF (ref. 2), can induce differentiation of epidermal stem cells in vitro. To determine the role of c-Myc in epidermal stem cells in vivo, we have targeted expression of human MYC2 to the hair follicles and the basal layer of mouse epidermis using a keratin 14 vector (K14.MYC2). Adult K14.MYC2 mice gradually lose their hair and develop spontaneous ulcerated lesions due to a severe impairment in wound healing; their keratinocytes show impaired migration in response to wounding. The expression of beta1 integrin, which is preferentially expressed in epidermal stem cells is unusually low in the epidermis of K14.MYC2 mice. Label-retaining analysis to identify epidermal stem cells reveals a 75% reduction in the number of stem cells in 3-month-old K14.MYC2 mice, compared with wildtype mice. We conclude that deregulated expression of c-Myc in stem cells reduces beta1 integrin expression, which is essential to both keratinocyte migration and stem cell maintenance.
Assuntos
Proteínas Proto-Oncogênicas c-myc/genética , Pele/patologia , Células-Tronco/fisiologia , Animais , Bromodesoxiuridina/metabolismo , Divisão Celular/genética , Movimento Celular/genética , Células Cultivadas , Regulação da Expressão Gênica no Desenvolvimento , Hiperplasia/genética , Integrina beta1/genética , Integrina beta1/metabolismo , Queratina-14 , Queratinócitos/patologia , Queratinas/genética , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-myc/metabolismo , Pele/embriologia , Células-Tronco/patologia , Cicatrização/genéticaRESUMO
A fast-sampling fast-ion D-alpha (F-FIDA) measurement has been developed in the large helical device in order to investigate fast ion dynamics associated with helically trapped fast-ion-driven Magnetohydrodynamic (MHD) bursts. F-FIDA consists of a multi-anode photomultiplier tube (PMT) and achieves a sampling rate of 10 kHz. During the deuterium experiment campaign in 2022, F-FIDA measured the spectrum of perpendicular fast ions, using perpendicular lines of sight. We compared F-FIDA with conventional FIDA, using an electron multiplying charge coupled device, and confirmed that the time-averaged images were generally consistent between the two. The statistical properties of the temporal evolution associated with MHD bursts were analyzed using a conditional sampling technique. The results showed that the PMT signal varied in different spatial and wavelength channels. Although the signal-to-noise ratio was poor and there was room for improvement, it could provide useful information for studies on the phase-space dynamics of fast ions.
RESUMO
The velocity distribution function is a statistical description that connects particle kinetics and macroscopic parameters in many-body systems. Laser-induced fluorescence (LIF) spectroscopy is utilized to measure the local velocity distribution function in spatially inhomogeneous plasmas. However, the analytic form of such a function for the system of interest is not always clear under the intricate factors in non-equilibrium states. Here, we propose a novel approach to select the valid form of the velocity distribution function based on Bayesian statistics. We formulate the Bayesian inference of ion velocity distribution function and apply it to LIF spectra locally observed at several positions in a linear magnetized plasma. We demonstrate evaluating the spatial inhomogeneity by verifying each analytic form of the local velocity distribution function. Our approach is widely applicable to experimentally establish the velocity distribution function in plasmas and fluids, including gases and liquids.
RESUMO
The epidermal cornified cell envelope (CE) is a complex protein-lipid composite that replaces the plasma membrane of terminally differentiated keratinocytes. This lamellar structure is essential for the barrier function of the skin and has the ability to prevent the loss of water and ions and to protect from environmental hazards. The major protein of the epidermal CE is loricrin, contributing approximately 70% by mass. We have generated mice that are deficient for this protein. These mice showed a delay in the formation of the skin barrier in embryonic development. At birth, homozygous mutant mice weighed less than control littermates and showed skin abnormalities, such as congenital erythroderma with a shiny, translucent skin. Tape stripping experiments suggested that the stratum corneum stability was reduced in newborn Lor(-/-) mice compared with wild-type controls. Isolated mutant CEs were more easily fragmented by sonication in vitro, indicating a greater susceptibility to mechanical stress. Nevertheless, we did not detect impaired epidermal barrier function in these mice. Surprisingly, the skin phenotype disappeared 4-5 d after birth. At least one of the compensatory mechanisms preventing a more severe skin phenotype in newborn Lor(-/-) mice is an increase in the expression of other CE components, such as SPRRP2D and SPRRP2H, members of the family of "small proline rich proteins", and repetin, a member of the "fused gene" subgroup of the S100 gene family.
Assuntos
Epiderme/fisiologia , Proteínas de Membrana/genética , Fenômenos Fisiológicos da Pele/genética , Adaptação Biológica , Sequência de Aminoácidos , Animais , Fenômenos Biomecânicos , Membrana Celular , Clonagem Molecular , Proteínas Ricas em Prolina do Estrato Córneo , Proteínas de Filamentos Intermediários/biossíntese , Proteínas de Membrana/deficiência , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Dados de Sequência Molecular , Permeabilidade , Proteínas S100/biossíntese , Regulação para CimaRESUMO
In this report, aortic arch replacement was performed successfully in 2 cases with our modified method placing priority on the cardiac and cerebral reperfusion, resulting in no postoperative cardiac or neurological complication. One was a 63-year-old man with old cerebral infarction and ischemic heart disease, and the other was a 72-year-old man with severe stenosis of the left common carotid arteries. Our method is similar to so-called "arch first technique". First, the ascending aorta is clamped and proximal anastomosis is accomplished during core cooling, followed by reconstruction of the brachiocephalic arteries under deep hypothermic circulatory arrest. Then perfusion of the heart and brain is restarted, while distal anastomosis is performed. It was proved that the method had several possible advantages such as minimized duration of brain ischemia and deep hypothermia, and elimination of direct cannulation to the branches of the aortic arch and a separate perfusion circuit for the brain.
Assuntos
Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/métodos , Encéfalo , Coração , Reperfusão/métodos , Idoso , Humanos , Hipotermia Induzida , Masculino , Pessoa de Meia-IdadeRESUMO
This is a report of 2 cases, in which preoperative 3-dimentional demonstration of the spinal cord artery with 64-row computed tomography was feasible, less invasive, less time-consuming, and helpful in making an interventional strategy for complex aortic disease, resulting in no postoperative paraplegia One was a 63-year-old man, who underwent total arch replacement and a long elephant trunk method for arch and descending aortic aneurysms. The length of the long elephant trunk was so determined that it ended between the descending aortic aneurysm and the origin of the spinal cord artery. The second case was a 59-year-old man, who underwent descending thoracic aorta replacement for type B aortic dissection. During the distal anastomosis, the dissection septa were trimmed in order to perfuse the blood into the true and 2 false channels, one of which was connected to the spinal cord artery. In this report, we are not suggesting that preservation of the demonstrated spinal cord artery is enough for spinal cord protection, because it is still controversial. Further study is needed to confirm the reliability and reproducibility of our methods.
Assuntos
Angiografia/métodos , Doenças da Aorta/cirurgia , Imageamento Tridimensional/métodos , Paraplegia/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Medula Espinal/irrigação sanguínea , Tomografia Computadorizada Espiral/métodos , Humanos , Masculino , Pessoa de Meia-IdadeAssuntos
Neoplasias dos Genitais Femininos/diagnóstico , Neoplasias dos Genitais Masculinos/diagnóstico , Doença de Paget Extramamária/diagnóstico , Biópsia de Linfonodo Sentinela/métodos , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Metástase Linfática/diagnóstico , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , PrognósticoAssuntos
Nervo Facial/fisiopatologia , Neoplasias de Cabeça e Pescoço/cirurgia , Neoplasias Cutâneas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Nervo Facial/cirurgia , Feminino , Neoplasias de Cabeça e Pescoço/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Cutâneas/fisiopatologiaRESUMO
Although type A acute aortic dissection is considered a surgical emergency, the optimal treatment of patients with preoperative cerebral malperfusion remains controversial. From September 1994 to December 2005, 68 consecutive patients with type A aortic dissection underwent emergent surgical treatment. Eight patients showed preoperative newly-developed neurological deficits. The hospital mortality rate was 25% (2 of the 8 patients). Of the 8 patients, 1 with preoperative coma died due to severe brain injury. Another with acute myocardial infarction and left hemiparesis died due to low output syndrome in the immediate postoperative period. Three of the others had persistent left hemiplegia. One of these patients showed new paraplegia early postoperatively. The preoperative neurological deficit of the remaining 3 patients had improved in some degree. The optimal strategy should be taken individually under the accurate and prompt evaluations of hemodynamic and neurological state in such patients.
Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Isquemia Encefálica/complicações , Circulação Cerebrovascular , Idoso , Dissecção Aórtica/mortalidade , Aneurisma da Aorta Torácica/mortalidade , Implante de Prótese Vascular , Procedimentos Cirúrgicos Cardíacos , Procedimentos Cirúrgicos Cardiovasculares , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-IdadeAssuntos
Antineoplásicos/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Hemangiossarcoma/tratamento farmacológico , Couro Cabeludo , Neoplasias Cutâneas/tratamento farmacológico , Taxoides/uso terapêutico , Idoso , Antineoplásicos/administração & dosagem , Biópsia , Docetaxel , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Hemangiossarcoma/secundário , Humanos , Linfonodos/patologia , Metástase Linfática , Couro Cabeludo/patologia , Neoplasias Cutâneas/patologia , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
Streptococcus milleri was isolated in pure culture from the pericardial fluid of a 42-year-old man with pulmonary tuberculosis. Pericardiectomy had to be done to cure the pericarditis.
Assuntos
Pericardite Constritiva/etiologia , Infecções Estreptocócicas , Adulto , Anticorpos Antibacterianos/análise , Cárie Dentária/microbiologia , Humanos , Masculino , Pericardite Constritiva/imunologia , Infecções Estreptocócicas/imunologia , Streptococcus/imunologia , Streptococcus/isolamento & purificação , SupuraçãoRESUMO
We studied the molecular genetic basis of a C1 inhibitor deficiency in a patient with type I hereditary angioneurotic edema using both the polymerase chain reaction and nucleotide sequencing. A single nucleotide change (T-->A) at the GT 5' donor splice recognition motif in the seventh intron of the C1 inhibitor gene was detected. A restriction site analysis of the C1 inhibitor gene in the patient's family indicated that this mutation is correlated with a decreased level of C1 inhibitor activity. A northern blot analysis demonstrated C1 inhibitor mRNA to have a normal size, but its contents were reduced by about 50% compared with a normal subject. As the donor splice site is essential for an excising of the intron during mRNA processing, aberrant mRNA splicing may cause a rapid degradation of the transcript, thus resulting in the onset of hereditary angioneurotic edema.
Assuntos
Angioedema/genética , Mutação Puntual/genética , Splicing de RNA , Inibidores de Serina Proteinase/genética , Adulto , Alelos , Sequência de Bases , Feminino , Humanos , RNA Mensageiro/genéticaRESUMO
Lazaroid, an inhibitor of iron-mediated lipid peroxidation, has been shown to reduce free radical-mediated injury after ischemia and reperfusion. We thus examined the efficacy of pretreatment with lazaroid (U74500A) in enhancing functional recovery after 24-hr heart preservation. An isolated rabbit heart model perfused with the blood from a support rabbit was used. Before preservation, either U74500A (4 mg/kg, group L; n = 6) or solvent (group S; n = 7) was given to the donor rabbit. After 24-hr preservation with UW solution at 0 degrees C, all hearts were perfused with cross-circulated blood for 60 min with the Langendorff mode followed by 40 min of the working mode. In group S, ventricular fibrillation (Vf) after reperfusion was observed in all hearts, whereas no Vf was observed in the U74500A-pretreated group. In group L, the serum creatine phosphokinase; its isozyme, troponin-T; and serum lipid peroxide levels after 10 min of reperfusion were all significantly (P < 0.05) lower than those in group S. The Frank-Starling curve (indicating the left atrial pressure-aortic flow relationship) showed a significant left and upward shift in group L compared with that in group S (P < 0.0001). The heart pretreated with U74500A showed less ischemia-reperfusion injury, better ventricular function, and a lower lipid peroxide level. We thus conclude that the inhibition of lipid peroxidation with lazaroid appears to offer some potential benefits for long-term heart preservation.
Assuntos
Antioxidantes/administração & dosagem , Transplante de Coração , Preservação de Órgãos , Pregnatrienos/administração & dosagem , Animais , Coração/fisiopatologia , Peroxidação de Lipídeos/efeitos dos fármacos , Perfusão , CoelhosRESUMO
Although Manouguian's operation is well established, there have been little long-term data published on its outcome. From January 1980 to June 1988, 15 patients underwent patch enlargement of the small aortic anulus by Manouguian's approach, either with aortic single valve replacement (7 patients) or with aortic-mitral double valve replacement (8 patients). Follow-up ranged from 3.0 to 11.4 years (mean 8.5) and was completed with a cumulative total of 102 patient-years. One patient died of fulminant hemolysis, probably related to turbulent jet flow and Dacron patch material (operative mortality 6.7%). There were four late deaths, and the actuarial survival, including operative death at 10 years, was 62% +/- 14%. Reoperations were performed seven times in six patients. Most of these complications were not considered to be caused by the anulus-enlarging procedure. Actuarial freedom rate from reoperation at 10 years was 65% +/- 15%. Four patients underwent rereplacement of prostheses for Hancock valve failure during 2.9 to 11.3 years (mean 8.2 years). The anulus enlargement was found to be well healed and presented no problem during reoperation. Surgically induced mitral regurgitation by Manouguian's procedure was observed in two patients. The regurgitation did not progress during follow-up duration of 1.9 to 10.0 years, nor did it cause congestive heart failure. Annular enlargement by Manouguian's procedure with use of mechanical valves is one of the good selections in patients with the narrow aortic valve ring.
Assuntos
Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas , Complicações Pós-Operatórias/mortalidade , Análise Atuarial , Adulto , Bioprótese/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/métodos , Criança , Feminino , Seguimentos , Próteses Valvulares Cardíacas/efeitos adversos , Próteses Valvulares Cardíacas/mortalidade , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/cirurgia , Complicações Pós-Operatórias/epidemiologia , Desenho de Prótese , Reoperação/estatística & dados numéricos , Análise de Sobrevida , Resultado do Tratamento , Obstrução do Fluxo Ventricular Externo/etiologia , Obstrução do Fluxo Ventricular Externo/cirurgiaRESUMO
From February 1975 through October 1981, 256 Hancock porcine bioprostheses (Johnson & Johnson Cardiovascular, King of Prussia, Pa.) (60 aortic, 169 mitral, and 27 pulmonary/tricuspid position) were implanted in 220 patients (104 male and 116 female, aged 9 to 67 years; mean 43.3) at Kyushu University Hospital in Japan. The procedures include 41 aortic valve replacements, 121 mitral valve replacements, 4 pulmonary valve replacements, 6 tricuspid valve replacements, and 48 combined valve replacements (31 aortic plus mitral, 13 mitral plus tricuspid, and 4 aortic plus mitral plus tricuspid). Hospital mortality was 6.4%. Follow-up was 98% during 8 to 14 (mean 10.5) years. Cumulative follow-up was 1836 patient-years and 2078 valve-years. At 10 years the overall actuarial survival rate, including hospital morality, was 70% +/- 3%, and freedom from valve-related mortality with sudden death was 87% +/- 3%. More than half of the current survivors required no anticoagulant therapy. Freedom from thromboembolism or anticoagulant-related hemorrhage (or both) and prosthetic valve endocarditis was common. Freedom from structural valve failure and reoperation declined more than 9 years after replacement of left-sided heart valves but not after replacement of right-sided heart valves. Sixty-seven patients underwent 68 repeat operations, and there were four deaths (5.9%). The rate of freedom from overall valve-related complications at 10 years was 62% +/- 8% for aortic valve replacement, 53% +/- 5% for mitral valve replacement, 80% +/- 13% for pulmonary/tricuspid valve replacement, and 42% +/- 9% for combined valve replacement. There was a significant difference between pulmonary/tricuspid valve replacement and combined valve replacement (p less than 0.05). The Hancock bioprosthesis is suitable for the replacement of valves in the right side of the heart but not for combined valve replacement.
Assuntos
Bioprótese/estatística & dados numéricos , Doenças das Valvas Cardíacas/cirurgia , Próteses Valvulares Cardíacas/mortalidade , Análise Atuarial , Adulto , Feminino , Seguimentos , Doenças das Valvas Cardíacas/mortalidade , Próteses Valvulares Cardíacas/efeitos adversos , Mortalidade Hospitalar , Humanos , Japão/epidemiologia , Masculino , Desenho de Prótese , Infecções Relacionadas à Prótese/epidemiologia , Reoperação , Taxa de Sobrevida , Fatores de TempoRESUMO
BACKGROUND: The lazaroid U74500A is a 21-aminosteroid that inhibits lipid peroxidation and attenuates ischemia-reperfusion injury. We examined the effect of U74500A on heart preservation with the use of a clinically relevant canine orthotopic heart transplantation model. METHODS AND RESULTS: Six donor dogs (group L) were pretreated intravenously with U74500A (10 mg/kg), and the dogs without pretreatment served as a control (group C, n = 6). The donor heart was preserved in cold University of Wisconsin solution for 24 hours. The heart was then transplanted orthotopically. Myocardial biopsy was performed to measure the adenosine triphosphate level at the end of ischemia. Before reperfusion, recipients in group L received another dose of U74500A (10 mg/kg) intravenously. After 3 hours of reperfusion, left ventricular function was evaluated by left ventricular pressure-volume relations with the use of a Millar catheter and conductance catheter, thereby deriving the slope of the end-systolic pressure-volume relation, the slope of the stroke work-- end-diastolic volume relation, and the slope of the maximum dP/dt--end-diastolic volume relation. At the same time, serum creatine kinase MB isoenzyme and lipid peroxide levels were measured. The slopes of the end-systolic pressure-volume relation, the stroke work--end-diastolic volume relation, and the maximum dP/dt--end-diastolic volume relation for group L were significantly higher than those for group C. The adenosine triphosphate levels for group L were significantly higher than those for group C. Serum creatine kinase MB isoenzyme and lipid peroxide levels for group L were significantly lower than those for group C. CONCLUSIONS: Inhibition of lipid peroxidation by the administration of U74500A was effective for 24-hour canine cardiac preservation. These results indicate that U74500A is a promising agent for heart allograft preservation.
Assuntos
Transplante de Coração , Peroxidação de Lipídeos/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Pregnatrienos/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Cães , Hemodinâmica , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio/metabolismo , Função Ventricular EsquerdaRESUMO
It is still controversial whether to pulse or not to pulse for the establishment of ideal extracorporeal circulation. We directly measured the renal sympathetic nerve activity in mongrel dogs (n = 10, weighing from 13 to 21 kg) to determine the effects of pulsatile and nonpulsatile systemic perfusion on the control of the sympathetic nerve activity during left ventricular assistance. Pulsatile perfusion was generated with an air-driven, diaphragm-type blood pump, and nonpulsatile perfusion was generated with a centrifugal pump. Renal sympathetic nerve activity and the blood flow of the descending aorta were then recorded during pulsatile and nonpulsatile systemic perfusion. Other variables, such as mean arterial pressure, central venous pressure, left atrial pressure, and blood gas levels, were kept constant. At the same mean arterial pressure, renal sympathetic nerve activity during pulsatile perfusion decreased significantly to 80% of renal sympathetic nerve activity during nonpulsatile perfusion (26.8 +/- 2.4 vs 33.4 +/- 2.9 spikes/sec, p < 0.01). Total systemic vascular resistance during pulsatile perfusion decreased significantly to 85% of that during nonpulsatile perfusion (5700 +/- 580 vs 6667 +/- 709 dynes.sec.cm-5, p < 0.05). These results suggest that pulsatile systemic perfusion, compared with nonpulsatile systemic perfusion, reduces sympathetic nerve activity and peripheral vascular resistance and thus may improve both microcirculation and organ function.
Assuntos
Circulação Extracorpórea , Rim/inervação , Fluxo Pulsátil/fisiologia , Sistema Nervoso Simpático/fisiologia , Animais , Cães , Hemodinâmica , Resistência VascularRESUMO
From February 1975 to August 1981, 23 consecutive patients underwent tricuspid valve replacement, which was either isolated (six patients) or combined with the replacement of other valves (17) by means of a standard, glutaraldehyde-preserved Hancock porcine bioprostheses. Patients' ages ranged from 9 to 53 (mean 36.2) years. The follow-up period ranged from 0.2 to 16.5 years (mean 9.1) and was complete in 100% of all cases. Structural valve failure of the tricuspid Hancock valve was noticed in two patients, a 9-year-old boy and a 13-year-old girl 3.4 and 16.5 years after implantation, respectively. The actuarial freedom rate from structural valve failure at 10 years was 94 +/- 6%. There were six tricuspid prosthesis-related events: structural valve failure in two and valve thrombosis, anticoagulant-related bleeding, prosthetic valve endocarditis, and periprosthetic leak in one each, respectively. The actuarial freedom from these events at 10 years was 78 +/- 10%. Five pairs of aortic/mitral-tricuspid Hancock valves were explanted simultaneously from the same patients after 8.1 to 13.9 (mean 11.4) years postoperatively. A gross examination showed no valve dysfunction in the explants from the tricuspid position, but degenerative changes with valve dysfunction in those from the mitral and aortic position were observed (none of five versus five of seven; p < 0.03). We concluded that the selection of a Hancock bioprosthesis in the tricuspid position is acceptable because of the low incidence of prosthesis-related complications and the excellent durability of more than 10 years.
Assuntos
Bioprótese , Próteses Valvulares Cardíacas , Análise Atuarial , Adolescente , Adulto , Valva Aórtica , Criança , Endocardite/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/mortalidade , Desenho de Prótese , Falha de Prótese , Infecções Relacionadas à Prótese/epidemiologia , Reoperação/estatística & dados numéricos , Análise de Sobrevida , Valva Tricúspide/cirurgiaRESUMO
OBJECTIVE: Amrinone, a selective phosphodiesterase III inhibitor, is reported to have a potent inotropic effect on the left ventricle, but the effects of this drug on right ventricular contractility in the clinical setting are unknown. The concept of ventricular/arterial coupling was applied to investigate the effects of amrinone on right ventricular contractility and afterload with transesophageal echocardiography. METHODS AND RESULTS: The study was performed in the intensive care unit with 11 patients who had undergone cardiac operations. Right ventricular cross-sectional area was measured with transesophageal echocardiography equipped with a capability of automated border detection as a surrogate for right ventricular volume. Multiple pressure-area loops were obtained by reducing preload to measure end-systolic elastance and effective arterial elastance. External work and pressure-volume area were also measured to calculate the efficiency of energy transfer from pressure-volume area to external work. Nitroprusside (0.3 to 0.5 microg x kg(-1) x min(-1)) and amrinone (1 mg x kg(-1) intravenously followed by 10 microg x kg(-1) x min(-1)) were administered. With nitroprusside infusion, end-systolic elastance and effective arterial elastance remained unchanged (end-systolic elastance, 4.73 +/- 2.18 mm Hg/cm2 to 4.65 +/- 2.09 mm Hg/cm2; effective arterial elastance, 8.05 +/- 3.84 mm Hg/cm2 to 7.70 +/- 3.64 mm Hg/cm2). In contrast, amrinone reduced afterload (effective arterial elastance, 8.82 +/- 3.99 mm Hg/cm2 to 7.05 +/- 4.01 mm Hg/cm2, p = 0.004) and enhanced contractility (end-systolic elastance, 4.47 +/- 1.79 mm Hg/cm2 to 6.56 +/- 2.22 mm Hg/cm2, p = 0.007). Consequently, amrinone decreased the ventricular/arterial coupling ratio (effective arterial elastance/end-systolic elastance, 2.40 +/- 1.45 to 1.16 +/- 0.63, p = 0.009) and improved the efficiency of energy transfer (external work/pressure-volume area, 0.44 +/- 0.15 to 0.54 +/- 0.15, p = 0.013). CONCLUSIONS: Right ventricular pressure-area relations obtained with transesophageal echocardiography could successfully separate the simultaneous change in right ventricular systolic mechanics and afterload caused by amrinone. Amrinone caused enhancement of right ventricular contractility and afterload reduction.