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1.
Artif Organs ; 44(11): E482-E493, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32364253

RESUMO

The objective of this study was to evaluate the effect of chemical treatment with glutamic acid to avoid calcification of biological cardiac valves. The bovine pericardium (BP) tissues were fixed with 0.5% glutaraldehyde (BP/GA), followed by treatment with glutamic acid (BP/GA + Glu) for neutralization of the free aldehyde groups. Microscopic analysis showed that the wavy structure of collagen fibrils was preserved, but changes in elastin's integrity occurred. However, the treatment did not promote undesirable changes in the thermal and mechanical properties of the modified BPs. These samples were systematically studied in rat subcutaneous tissue: control (BP/GA) and anticalcificant (BP/GA + Glu). After 60 days, both groups induced similar inflammatory reactions. In terms of calcification, BP/GA + Glu remained more stable with a lower index (3.1 ± 0.2 µg Ca2+ /mg dry tissue), whereas for BP/GA it was 5.7 ± 1.3 µg Ca2+ /mg dry tissue. Bioprostheses made from BP/GA + Glu were implanted in the pulmonary position in sheep, and in vivo echocardiographic analyses revealed maintenance of valvar function after 180 days, with low gradients and minimal valve insufficiency. The explanted tissues of the BP/GA + Glu group had a lower average calcium content 3.8 ± 3.0 µg Ca2+ /mg dry tissue. The results indicated high anticalcification efficiency of BP/GA + Glu in both subcutaneous implant in rats and in the experimental sheep model, which is an advantage that should encourage the industrial application of these materials for the manufacture of bioprostheses.


Assuntos
Bioprótese , Calcificação Fisiológica/efeitos dos fármacos , Bovinos , Ácido Glutâmico/farmacologia , Próteses Valvulares Cardíacas , Animais , Bovinos/fisiologia , Glutaral/farmacologia , Valvas Cardíacas/efeitos dos fármacos , Valvas Cardíacas/fisiologia , Pericárdio/efeitos dos fármacos , Pericárdio/fisiologia
2.
Clin Exp Nephrol ; 19(5): 783-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25630669

RESUMO

BACKGROUND: The therapeutic potential of adult stem cells in the treatment of chronic diseases is becoming increasingly evident. In the present study, we sought to assess whether treatment with mesenchymal stem cells (MSCs) efficiently retards progression of chronic renal failure (CRF) when administered to experimental models of less severe CRF. METHODS: We used two renal mass reduction models to simulate different stages of CRF (5/6 or 2/3 mass renal reduction). Renal functional parameters measured were serum creatinine (SCr), creatinine clearance (CCr), rate of decline in CCr (RCCr), and 24-h proteinuria (PT24h). We also evaluated renal morphology by histology and immunohistochemistry. MSCs were obtained from bone marrow aspirates and injected into the renal parenchyma of the remnant kidneys of both groups of rats with CRF (MSC5/6 or MSC2/3). RESULTS: Animals from groups MSC5/6 and CRF2/3 seemed to benefit from MSC therapy because they showed significantly reduction in SCr and PT24h, increase in CCr and slowed the RCCr after 90 days. Treatment reduced glomerulosclerosis but significant improvement did occur in the tubulointerstitial compartment with much less fibrosis and atrophy. MSC therapy reduced inflammation by decreasing macrophage accumulation proliferative activity (PCNA-positive cells) and fibrosis (α-SM-actin). Comparisons of renal functional and morphological parameters responses between the two groups showed that rats MSC2/3 were more responsive to MSC therapy than MSC5/6. CONCLUSION: This study showed that MSC therapy is efficient to retard CRF progression and might be more effective when administered during less severe stages of CRF.


Assuntos
Falência Renal Crônica/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Actinas/biossíntese , Actinas/genética , Animais , Proliferação de Células , Creatinina/metabolismo , Progressão da Doença , Feminino , Fibrose/patologia , Glomerulosclerose Segmentar e Focal/patologia , Glomerulosclerose Segmentar e Focal/terapia , Rim/patologia , Falência Renal Crônica/patologia , Testes de Função Renal , Macrófagos/patologia , Células-Tronco Mesenquimais , Antígeno Nuclear de Célula em Proliferação/biossíntese , Antígeno Nuclear de Célula em Proliferação/genética , Proteinúria/metabolismo , Ratos , Ratos Wistar
3.
Artif Organs ; 35(5): 484-9, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21595716

RESUMO

Major problems with biological heart valves post-implantation are associated with progressive structural deterioration and calcification attributed to glutaraldehyde processing, dead cells, and cell fragments present in the native tissue. In spite of these problems, glutaraldehyde still is the reagent of choice. The results with acellular matrix xenograft usually prepared by detergent treatment in association with enzymes are rather conflicting because while preserving mechanical properties, tissue morphology and collagen structure are process dependent. This work describes a chemical approach for the preparation of an acellular bovine pericardium matrix intended for the manufacture of heart valve bioprostheses. Cell removal was performed by an alkaline extraction in the presence of calcium salts for periods ranging from 6 to 48 h. The results showed that cell removal was achieved after 12 h, with swelling and negative charge increasing with processing time. Nevertheless, collagen fibril structure, ability to form fibrils, and stability to collagenase were progressive after 24-h processing. There was no denaturation of the collagen matrix. A process is described for the preparation of acellular bovine pericardium matrices with preserved fibril structure and morphology for the manufacture of cardiac valve bioprostheses and may be used in other applications for tissue reconstruction.


Assuntos
Bioprótese , Implante de Prótese de Valva Cardíaca/instrumentação , Próteses Valvulares Cardíacas , Pericárdio/transplante , Animais , Varredura Diferencial de Calorimetria , Bovinos , Colagenases/metabolismo , Reagentes de Ligações Cruzadas/farmacologia , Glutaral/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Teste de Materiais , Metais Alcalinos/farmacologia , Metais Alcalinoterrosos/farmacologia , Microscopia Eletrônica de Varredura , Pericárdio/citologia , Pericárdio/efeitos dos fármacos , Pericárdio/metabolismo , Pericárdio/ultraestrutura , Desenho de Prótese , Fatores de Tempo
4.
Artif Organs ; 35(5): 497-501, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21595718

RESUMO

Calcification is one of the major causes of failure of heart valve bioprostheses (HVBs) derived from glutaraldehyde (GA)-processed bovine pericardium (BP) or porcine aortic valves. New crosslinking reagent procedures are still far from giving satisfactory results, and this is the main reason why GA is still the reagent of choice for the fixation of native tissue intended for HVB manufacture. Nevertheless, two new findings with respect to GA processing may significantly improve HVB performance postimplantation: the finding that increasing concentrations of GA result in a decrease in calcification; the blocking of free aldehyde usually by nucleophyles or the treatment of processed material at low pH. This work investigates the in vitro properties of BP fixed with GA followed by the treatment with glutamic acid under alkaline conditions in order to prepare BP materials with lower calcification potential postimplantation. In comparison to conventional processing, except for the tensile strength that was slightly lower, elongation and toughness were higher than the accepted values. No significant differences were observed in the performance indexes (mean pressure gradient, mean effective area, regurgitant fraction, performance and efficiency indexes) with wear resistance over 150 × 106 cycles. These results indicate that the processing of BP described in this work may be of potential use in the manufacture of HVBs.


Assuntos
Bioprótese , Reagentes de Ligações Cruzadas/farmacologia , Ácido Glutâmico/farmacologia , Glutaral/farmacologia , Implante de Prótese de Valva Cardíaca/instrumentação , Próteses Valvulares Cardíacas , Pericárdio/efeitos dos fármacos , Animais , Fenômenos Biomecânicos , Calcinose/etiologia , Calcinose/prevenção & controle , Bovinos , Reagentes de Ligações Cruzadas/efeitos adversos , Análise de Falha de Equipamento , Ácido Glutâmico/efeitos adversos , Glutaral/efeitos adversos , Próteses Valvulares Cardíacas/efeitos adversos , Implante de Prótese de Valva Cardíaca/efeitos adversos , Temperatura Alta , Hidrodinâmica , Concentração de Íons de Hidrogênio , Teste de Materiais , Pericárdio/transplante , Desenho de Prótese , Falha de Prótese , Resistência à Tração
5.
Heart Surg Forum ; 13(1): E17-20, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20150033

RESUMO

BACKGROUND: The aim of this study was to assess by Doppler echocardiography (ECO) the functioning of the mitral valve apparatus in patients who have undergone implantation of standardized bovine pericardium chordae (SBPC) for replacement of ruptured or elongated chordae tendineae with significant thinning. METHODS: SBPC were implanted in 31 patients who had mitral insufficiency due to rupture of chordae tendinae or elongated chordae with significant thinning. Patient ages ranged from 19 to 85 years (mean of 58 years). The most frequent cause of mitral insufficiency was fibroelastic degeneration in 25 patients (80.6%). The SBPC were fashioned as a set, joined at their extremities by 2 polyester-reinforced rods forming a monobloc. The SBPC were 2-mm wide and were positioned parallel to one another at a distance of 3 mm. Each set of SBPC had a corresponding measurer, and their length ranged from 20 to 35 mm. In 21 patients (67.7%) the SBPC were implanted in the posterior leaflet and in 10 patients (32.3%) in the anterior leaflet (in 2 patients concurrently in the anterior and posterior leaflets). All patients were assessed by ECO postoperatively, with a 20-month mean follow-up time (range 6-45 months). RESULTS: One patient (3.2%) died of pulmonary embolism during the early postoperative period. Postoperative ECO showed absence of mitral regurgitation in 17 patients (54.8%), mild regurgitation in 9 (29.0%), and mild-to-moderate regurgitation in 4 (12.9%). Opening and mobility of the mitral valve were normal in the 30 surviving patients. CONCLUSION: The ECO revealed good functionality of the mitral valve apparatus with appropriate leaflet coaptation in patients who had undergone implantation of SBPC for replacement of ruptured or elongated and thinned chordae. A longer follow-up is required to assess absence of calcification and/or degeneration of the SBPC.


Assuntos
Cordas Tendinosas/diagnóstico por imagem , Cordas Tendinosas/transplante , Ruptura Cardíaca/etiologia , Ruptura Cardíaca/cirurgia , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/cirurgia , Adulto , Idoso , Animais , Bovinos , Feminino , Ruptura Cardíaca/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/diagnóstico por imagem , Ruptura Espontânea/diagnóstico por imagem , Ruptura Espontânea/cirurgia , Resultado do Tratamento , Ultrassonografia
6.
Int Wound J ; 7(3): 191-3, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20602649

RESUMO

The aim of this work was to dynamically study pressure variations exerted by elastic compression stockings during walking. While study participants walked, the pressure variations at the interface between elastic stockings and the skin were measured dynamically. Three healthy individuals wearing 10/20 and 20/30 elastic compression stockings manufactured by Sigvaris((R)) (Jundiai, São Paulo-Brazil) were requested to walk along a course for ten times at a constant speed. For every event, an apparatus specifically developed for the study and programmed to take readings at half-second intervals was used to measure the pressure exerted by the elastic stockings. The pressure exerted by the 10/20 stockings varied between 5 and 32 mmHg and for the 20/30 stockings it varied from 10 to 52 mmHg. Elastic stockings with larger pressures generate larger pressure variations during muscle activity (P-value < 0.001). In conclusion, muscle movements during walking cause the pressure exerted by elastic stockings on the leg to vary; thus, the pressure is not constant but has peaks and troughs according to the type of muscle movement and the gradient of the stockings.


Assuntos
Fenômenos Fisiológicos da Pele , Meias de Compressão , Caminhada/fisiologia , Adulto , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino , Teste de Materiais/instrumentação , Teste de Materiais/métodos , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Postura/fisiologia , Pressão , Meias de Compressão/normas
7.
Braz J Cardiovasc Surg ; 35(4): 549-554, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32864936

RESUMO

INTRODUCTION: The medical use of three-dimensional (3-D) images has been a topic in the literature since 1988, but 95% of papers on 3-D printing were published in the last six years. The increase in publications is the result of advances in 3-D printing methods, as well as of the increasing availability of these machines in different hospitals. This paper sought to review the literature on 3-D printing and to discuss thoughtful ideas regarding benefits and challenges to its incorporation into cardiothoracic surgeons' routines. METHODS: A comprehensive and systematic search of the literature was performed in PubMed and included material published as of March 2020. RESULTS: Using this search strategy, 9,253 publications on 3-D printing and 497 on "heart" 3-D printing were retrieved. CONCLUSION: 3-D printed models are already helping surgeons to plan their surgeries, helping patients and their families to understand complex anatomy, helping fellows and residents to practice surgery, even for rare cases, and helping nurses and other health care staff to better understand some conditions, such as heart diseases.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cardiopatias , Coração , Cardiopatias/cirurgia , Humanos , Modelos Anatômicos , Impressão Tridimensional
8.
South Med J ; 101(7): 748-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18580711

RESUMO

We report two cases of acute compartment syndrome in the anterior compartment of the lower limbs of patients with the diagnosis of Buerger disease associated with positive anticardiolipin antibodies. We comment on the rarity of the case and on the possibility of interference of two associated thrombogenic conditions. The need for early fasciotomy is emphasized since the progression to necrosis is time dependent. Fasciotomy was the only reperfusion surgery utilized on these patients with resolution of the ischemia.


Assuntos
Síndrome do Compartimento Anterior/complicações , Fumar/efeitos adversos , Tromboangiite Obliterante/complicações , Adulto , Síndrome do Compartimento Anterior/diagnóstico , Síndrome do Compartimento Anterior/cirurgia , Feminino , Humanos , Perna (Membro)/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Trombose Venosa/etiologia
9.
Cardiol Res ; 9(2): 75-82, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29755623

RESUMO

The mortality rate of post-infarction cardiogenic shock (CS) was 80.0-90.0%. Recent studies show a significant reduction of hospital mortality to approximately 50.0%. CS is defined as systemic tissue hypoperfusion resulting from systolic and/or diastolic heart dysfunction, the main cause of which is acute myocardial infarction (AMI). The main predictors are biological markers such as troponin, CKMB and lactate. A systematic literature review and meta-analysis is performed in order to present and correlate the main literary findings on CS and its evolution with possible changes in biomarkers such as troponin, lactate and CKMB. After criteria of literary search with the use of the mesh terms: cardiogenic shock; acute myocardial infarction; biomarkers; troponin; CKMB; lactate; clinical trials and use of the bouleanos "and" between the mesh terms and "or" among the historical findings. In the main databases such as Pubmed, Medline, Bireme, EBSCO, Scielo, etc., a total of 96 papers that were submitted to the eligibility analysis were collated and, after that, 41 studies were selected, following the rules of systematic review - PRISMA (Transparent reporting of systematic reviews and meta-analyzes-http://www.prisma-statement.org/). Some risk factors for its development in AMI are advanced age, female gender, anterior wall infarction, diabetes mellitus, systemic arterial hypertension, previous history of infarction and angina. The CS associated with AMI depends on its extent and its complications, being the main ones: mitral regurgitation, rupture of the interventricular septum and rupture of the free wall of the left ventricule. The diagnosis is based on the clinical manifestations, such as mental confusion, oliguria, hypotension, tachycardia, fine pulse, sweating, and cold extremities; in hemodynamic aspects: systolic blood pressure was < 90.0 mm Hg or 30 mm Hg below baseline, pulmonary capillary pressure was > 18.0 mm Hg and cardiac index was < 2.2 L/min/m2. Laboratory and imaging exams should be requested to evaluate the possible etiology of CS, its systemic repercussions and comorbidities. The treatment aims at the rapid reestablishment of the blood flow in the affected artery, to improve the patient's prognosis. The biomarkers dosage in the daily clinical practice of the different cardiological centers can facilitate the diagnosis and the conduction of the dubious cases and the best evaluation of the degree of myocardial suffering after CS.

10.
Rev Assoc Med Bras (1992) ; 53(5): 407-13, 2007.
Artigo em Português | MEDLINE | ID: mdl-17952349

RESUMO

OBJECTIVE: To analyze the biochemical profile and to characterize metabolic syndrome (MS) in patients with cardiologic medical assistance using NCEP-ATPIII and IDF definitions. METHODS: Two hundred patients and 140 controls were studied, considering total cholesterol (TC), HDL-cholesterol (HDLc), LDL-cholesterol (LDLc), VLDL-cholesterol (VLDLc), triglycerides (TG), fasting glycemia, abdominal waist and hypertension. Significance level was defined as P<0.05. RESULTS: Patients showed increased glycemia levels (103+/-31.4 mg/dL) and reduced HDLc levels (48+/-13.4 mg/dL) when compared to controls (88+/-29.7 mg/dL, P<0.0001 and 53+/-15.9 mg/dL, P=0.0075; respectively). Male controls 31-50 years old showed increased TC levels (215+/-40.4 mg/dL), LDL-cholesterol (134+/-34 mg/dL), VLDL-cholesterol (30+/-11.8 mg/dL) and TG (150+/-59.4 mg/dL) when compared to women (185+/-38.2 mg/dL, P=0.0137; 111+/-35.8 mg/dL; P=0.0324; 19+/-9.7 mg/dL; P=0.0009; 93+/-49 mg/dL, P=0.0010; respectively). Women over 50 years of age showed increased TC concentrations (216+/-35.9 mg/dL), HDL-cholesterol (54+/-12.8 mg/dL) and LDL-cholesterol (138+/-30.8 mg/dL) when compared to men (190+/-44.7 mg/dL, P=0.0103; 47+/-14.5 mg/dL, P=0.0229; 119+/-33.3 mg/dL; P=0.0176; respectively). NCEP-ATPIII and IDF definitions had characterized MS in 35.5% and 46% of patients, respectively, bolding glycemia, TG and hypertension. CONCLUSION: Elevated glycemia levels and reduced HDLc levels were detected in patients. Altered lipid profile observed in men 31-50 years old signals higher risk for cardiovascular diseases in young adults, while a similar profile in aged women can reflect hormonal physiological changes. Both definitions for MS diagnosis discriminate patients from controls, especially IDF, sometimes with lower capacity to determine high risk for cardiovascular complications. The high prevalence of MS in patients, even with cardiologic medical assistance, suggests predisposition for cardiovascular manifestations in Brazilian individuals.


Assuntos
Glicemia , Doenças Cardiovasculares/etiologia , Colesterol/sangue , Lipídeos/sangue , Síndrome Metabólica/epidemiologia , Adulto , Biomarcadores/sangue , Brasil/epidemiologia , Estudos de Casos e Controles , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/etiologia , Masculino , Síndrome Metabólica/diagnóstico , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Distribuição por Sexo , Fatores Sexuais , Triglicerídeos/sangue , Relação Cintura-Quadril
11.
Acta Cir Bras ; 22(1): 43-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17293949

RESUMO

PURPOSE: To study the effectiveness of the continuous, blood, antegrade-retrograde cardioplegia in an experimental model of isolated heart, evaluating ventricular function. METHODS: Rabbits were divided into four groups: Control--C(n=10); ischemic crystalloid cardioplegia--IC(n=10); ischemic blood cardioplegia--IB(n=10); ischemic non cardioplegia--INC(n=10). After the ischemic protocol period the ventricular function was analyzed by the intra-ventricular balloon technique. RESULTS: the intra-ventricular developed pressure (IVDP) was: C(92.90 +/- 6.86mmHg); IC(77.78 +/- 6.15mmHg); IB(93.64 +/- 5.09mmHg); INC(39.46 +/- 8.91mmHg) p< 0.005. The first derivative of intra-ventricular pressure in its positive deflection was: C(1137.50 +/- 92.23mmHg/sec); IC(1130.62 +/- 43.78mmHg/sec); IB(1187.58 +/- 88.38mmHg/sec); INC(620.02 +/- 43.80mmHg/se) p<0.005. The first derivate pressure in its negative deflection was: C(770.00 +/- 73.41mmHg/sec); IC(610.03 +/- 47.43mmg/sec); IB(762.53 +/- 46.02mmHg/sec); INC(412.35 +/- 84.36mmHg/sec) p< 0,005. The stress-strain angular logarithmic coefficient was: C(0.108 +/- 0.02); IC(0.159 +/- 0.038); IB(0.114 +/- 0.016); INC(0.175 +/- 0.038) p< 0.05. CONCLUSION: The ischemic group protected by blood cardioplegia showed better ventricular function than ischemic group protected by crystalloid cardioplegia and the non protected group.


Assuntos
Sangue , Soluções Cardioplégicas/farmacologia , Parada Cardíaca Induzida/métodos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Função Ventricular Direita , Animais , Soluções Cristaloides , Modelos Animais de Doenças , Feminino , Balão Intra-Aórtico , Soluções Isotônicas/farmacologia , Masculino , Coelhos , Estresse Mecânico , Pressão Ventricular/efeitos dos fármacos
12.
Angiology ; 57(1): 79-83, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16444460

RESUMO

Anticardiolipin antibodies represent one of the main hypercoagulation states associated with venous thromboembolism. The aim of this work was to evaluate symptomatic recurrent thrombosis in patients with anticardiolipin antibodies and deep vein thrombosis of the lower limbs with or without thromboembolism. Sixty patients who suffered from deep vein thrombosis were observed for a 5-year period, whether they had anticardiolipin antibodies or not. The group was made up of 34 females and 26 males with ages ranging from 13 to 73 years. All were diagnosed with deep vein thrombosis by means of phlebography and were tested for anticardiolipin antibodies by use of the ELISA method. The symptomatic signs of recurrent thrombosis were evaluated during this period. In total, 56.6% of the group were considered above normal for anticardiolipin antibodies, 25% positive, another 31.6% borderline, and 43.4% negative. Patients were tested positive when the anticardiolipin antibody count was >15 units/mL, borderline between 10 and 15 units/mL, and normal when <10 units/mL. The method of relative risk was used for statistical analysis of the results. Four positive patients, 1 borderline, and 1 normal patient had recurrent events of thrombosis. In the statistical analysis the relative risk for recurrent thrombosis in the positive patients was 6.0; CI 95%; 1.2 to 29.5. In conclusion patients with deep vein thrombosis who are positive for anticardiolipin antibodies present a higher risk of recurrent thrombosis.


Assuntos
Anticorpos Anticardiolipina/imunologia , Tromboembolia/imunologia , Trombose Venosa/imunologia , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Fatores de Risco , Tromboembolia/sangue , Tromboembolia/complicações , Trombose Venosa/sangue , Trombose Venosa/complicações
13.
Clinics (Sao Paulo) ; 61(5): 395-400, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17072436

RESUMO

OBJECTIVE: To determinate the extension and the resistance of the primary mitral valve chordae tendineae when submitted to traction. The importance of keeping the integrity of papillary muscle, chordae tendineae, and mitral valve cuspid when the replacement of this valve occurs is clear, but the knowledge of the maximum resistance that a primary tendinea chorda can withstand is not known. METHODS: Eight hearts were dissected, and one hundred and thirty two primary human chordae tendineae were measured (length and thickness) and submitted to traction under controlled conditions so that the absolute resistance, resistance relative to thickness (relative resistance), and elongation could be measured. RESULTS: The correlation between the elongation at the moment of rupture and the thickness was equal to 1.54 + 17.02 x thickness (P = 0.026); and to absolute resistance was equal to 0.95 + 1.42 x resistance (P < 0.001); and to the resistance relative to thickness (relative resistance) was equal to 1.95 + 0.08 x relative resistance (P = 0.009). The correlation between the absolute resistance and the thickness was equal to 0.26 + 14.53 x thickness (P < 0.001). CONCLUSION: The resistance of primary mitral valve chordae tendineae is associated with its thickness and elongation at the moment of rupture, but is not associated with the length. The elongation at the moment of rupture shows a relationship with the resistance relative to thickness (relative resistance) and with the thickness of the primary chordae tendineae, but not with the length of the chordae tendineae.


Assuntos
Cordas Tendinosas/fisiologia , Valva Mitral/fisiologia , Contração Miocárdica/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Elasticidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculos Papilares/fisiologia , Ruptura , Estresse Mecânico
14.
Arq Bras Cardiol ; 86(4): 261-7, 2006 Apr.
Artigo em Português | MEDLINE | ID: mdl-16680290

RESUMO

OBJECTIVE: To present a technical proposal based on the experience of 130 implantations using a simplified technique for coronary sinus catheterization, based on the atrial component of the intracavitary electrogram and radiological anatomy. METHODS: From October, 2001 to October, 2004, 130 biventricular pacemaker implantations were performed, using radiological anatomy and observation of the intracavitary electrogram, focusing on the atrial component. RESULTS: The implantation of the system using left ventricular pacing via coronary sinus was not possible in 8 patients. Difficulties on the cannulation of the coronary ostium were felt in 12 patients and difficulties of lead advancement through the coronary sinus were felt in 15 patients. The mean time of radioscopy utilization was 18.69 min. CONCLUSION: The implantation technique, using the atrial component morphology of the intracavitary electrogram and radiological anatomy showed to be workless, safe and effective for the cannulation of the coronary sinus ostium requesting reduced time of radioscopy.


Assuntos
Cateterismo Cardíaco/métodos , Eletrocardiografia , Sistema de Condução Cardíaco/fisiologia , Insuficiência Cardíaca/terapia , Marca-Passo Artificial , Adulto , Idoso , Idoso de 80 Anos ou mais , Bloqueio de Ramo/fisiopatologia , Bloqueio de Ramo/terapia , Cardiomiopatia Dilatada/fisiopatologia , Cardiomiopatia Dilatada/terapia , Feminino , Átrios do Coração/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Nó Sinoatrial/diagnóstico por imagem , Nó Sinoatrial/fisiopatologia , Resultado do Tratamento , Função Ventricular Esquerda/fisiologia
15.
J Chin Med Assoc ; 68(9): 435-6, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16187601

RESUMO

Pseudoaneurysms of the internal iliac artery are uncommon and are usually associated with trauma. We report the case of a 32-year-old man with a 15-day history of trauma to the abdomen and edema of the lower left limb. An arteriogram demonstrated proximal occlusion of the popliteal artery and a pseudoaneurysm in the internal iliac artery. Embolization of the pseudoaneurysm was performed using segments of guide wire that occluded the pseudoaneurysm, followed by proximal occlusion, which was accomplished using coils. An arteriogram after the procedure revealed adequate occlusion of the lesion. This association of guide wires and coils is a treatment option in cases of pseudoaneurysm of the internal iliac artery with large volumes needing to be occluded.


Assuntos
Falso Aneurisma/terapia , Embolização Terapêutica , Artéria Ilíaca , Adulto , Humanos , Masculino
16.
Arq Bras Cardiol ; 84(4): 297-303, 2005 Apr.
Artigo em Português | MEDLINE | ID: mdl-15880202

RESUMO

OBJECTIVE: To demonstrate the viability of the use of extracorporeal circulation established between the left atrium and ascending aorta to induce deep hypothermia for correcting thoracic and thoracoabdominal aortic aneurysms. METHODS: From January 1994 to July 2001, 38 patients (mean age, 54.6 +/- 12.7 years) were operated on as follows: 12 (31.6%) patients underwent repair of thoracoabdominal aortic aneurysm, and 26 patients underwent repair of descending thoracic aneurysms. Deep hypothermia was induced by use of extracorporeal circulation, with pharyngeal temperature ranging from 15 to 25 degrees C (20.6 +/- 3.2 degrees C). RESULTS: Of the neurological complications, paraplegia occurred in 2 (5.3%) patients. One patient developed paraparesis, and another evolved with convulsion. Twelve (31.6%) patients had respiratory complications, and 2 (16.7%) patients died. Two other patients were operated on on an emergency basis and ended up dying. Total mortality was 18.4% (7 patients). CONCLUSION: Repair of descending thoracic and thoracoabdominal aortic aneurysms with deep hypothermia by use of extracorporeal circulation established between the left atrium and ascending aorta proved to be a viable method for correcting those aneurysms.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Circulação Extracorpórea/métodos , Adulto , Idoso , Anastomose Cirúrgica , Cateterismo Venoso Central/métodos , Feminino , Humanos , Hipotermia Induzida/métodos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Toracotomia , Resultado do Tratamento
17.
Braz J Cardiovasc Surg ; 30(6): 636-43, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26934404

RESUMO

Surgical ablation, concomitant with other operations, is an option for treatment in patients with chronic atrial fibrillation. The aim of this study is to present a literature review on surgical ablation of atrial fibrillation in patients undergoing cardiac surgery, considering energy sources and return to sinus rhythm. A comprehensive survey was performed in the literature on surgical ablation of atrial fibrillation considering energy sources, sample size, study type, outcome (early and late), and return to sinus rhythm. Analyzing studies with immediate results (n=5), the percentage of return to sinus rhythm ranged from 73% to 96%, while those with long-term results (n=20) (from 12 months on) ranged from 62% to 97.7%. In both of them, there was subsequent clinical improvement of patients who underwent ablation, regardless of the energy source used. Surgical ablation of atrial fibrillation is essential for the treatment of this arrhythmia. With current technology, it may be minimally invasive, making it mandatory to perform a procedure in an attempt to revert to sinus rhythm in patients requiring heart surgery.


Assuntos
Técnicas de Ablação/normas , Fibrilação Atrial/cirurgia , Fontes de Energia Bioelétrica/normas , Ablação por Cateter/normas , Arritmia Sinusal/cirurgia , Arritmias Cardíacas/cirurgia , Humanos , Resultado do Tratamento
18.
Rev Bras Cir Cardiovasc ; 30(2): 246-53, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26107457

RESUMO

At present, many useful tools for reference management are available for use. They can be either off-line softwares or accessible Websites to all users in the internet. Their target is to facilitate the production of scientific text. But, to accomplish that, the featured bibliographic style should be effectively inserted, and the program has to be free. Here in this tutorial, we present Endnote Web®, a bibliographic reference management program comprising these two requirements: it contains the Brazilian Journal of Cardiovascular Surgery reference format and its use is free for charge after sign-in in IP registered terminal in Web of Science®.


Assuntos
Bibliografias como Assunto , Cardiologia , Sistemas de Gerenciamento de Base de Dados/normas , Publicações Periódicas como Assunto/normas , Redação/normas , Bases de Dados Bibliográficas , Armazenamento e Recuperação da Informação , Design de Software
19.
Rev. bras. cir. cardiovasc ; 35(4): 549-554, July-Aug. 2020. tab, graf
Artigo em Inglês | LILACS, SES-SP | ID: biblio-1137295

RESUMO

Abstract Introduction: The medical use of three-dimensional (3-D) images has been a topic in the literature since 1988, but 95% of papers on 3-D printing were published in the last six years. The increase in publications is the result of advances in 3-D printing methods, as well as of the increasing availability of these machines in different hospitals. This paper sought to review the literature on 3-D printing and to discuss thoughtful ideas regarding benefits and challenges to its incorporation into cardiothoracic surgeons' routines. Methods: A comprehensive and systematic search of the literature was performed in PubMed and included material published as of March 2020. Results: Using this search strategy, 9,253 publications on 3-D printing and 497 on "heart" 3-D printing were retrieved. Conclusion: 3 -D printed models are already helping surgeons to plan their surgeries, helping patients and their families to understand complex anatomy, helping fellows and residents to practice surgery, even for rare cases, and helping nurses and other health care staff to better understand some conditions, such as heart diseases.


Assuntos
Humanos , Cardiopatias/cirurgia , Procedimentos Cirúrgicos Cardíacos , Impressão Tridimensional , Coração , Modelos Anatômicos
20.
Clin Appl Thromb Hemost ; 8(1): 85-6, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11991245

RESUMO

The case of a 26-year-old male chronic smoker is reported, who had thrombotic incidences on three occasions in both upper and lower limbs over a 10-month period. Laboratory examinations, including hematologic studies and creatinine, cholesterol, and glucose levels, were normal. However, IgG and IgM anticardiolipin antibodies were detected. Duplex ultrasonography confirmed deep venous thrombosis in both lower limbs (two occurrences) and computer tomography depicted an inferior cava vein thrombosis. The patient fulfilled all of Shionoya's criteria for Buerger's disease, thus suggesting an association between anticardiolipin antibodies and this disease.


Assuntos
Anticorpos Anticardiolipina/sangue , Síndrome Antifosfolipídica/complicações , Tromboangiite Obliterante/diagnóstico , Adulto , Anticoagulantes/uso terapêutico , Heparina/uso terapêutico , Humanos , Masculino , Prognóstico , Doença de Raynaud/etiologia , Fumar/efeitos adversos , Abandono do Hábito de Fumar , Tromboangiite Obliterante/tratamento farmacológico , Tromboangiite Obliterante/etiologia , Tromboangiite Obliterante/terapia , Tromboflebite/etiologia , Varfarina/uso terapêutico
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