João Carlos Ferreira Leal

Thoracic endovascular aortic repair – a Brazilian experience in 255 patients over a period of 112 months

The aim of this study is to analyze the immediate and late evolution for death and reintervention in a thoracic endovascular aortic repair (TEVAR) group, over a follow-up period of 112 months. Retrospective data of 255 patients, from 1998 to 2007, were obtained. The most prevalent diseases were thoracic aortic aneurysms (89), thoracic and abdominal aneurysms (85) and thoracic aortic dissections (61). The mean age was 63.2 years and 67.1% were male. Three hundred and three endoprostheses were used. Causes of morbidity, in the immediate postoperative period, were hyperthermia (45.9%), endoleaks (9.8% - being 7.1% type I), vascular complications (5.2%), renal insufficiency (3.1%) and neurological complications (3.1%). There were two (0.8%) hospital deaths and 17 (6.7%) late deaths. Time of follow-up was up to 112 months (mean of 60 months). The Kaplan-Meier curve analysis showed an increase of reintervention, compared with death, after a follow-up period of 42 months. Freedom from death at 36, 60 and 112 months was 96%, 89.1%, 85.1% and for reintervention, for the same periods was 93.6%, 82.7%, 57.2%, respectively. This study showed low incidence of prostheses related morbidity and immediate mortality. After a period of 42 months there was an increase on the percentual tax of reintervention.

Perioperative serum troponin I levels are associated with higher risk for atrial fibrillation in patients undergoing coronary artery bypass graft surgery

Atrial fibrillation (AF) remains a frequent complication after coronary artery bypass graft surgery (CABG). We evaluate the association of AF occurrence and serum cardiac troponin I (cTnI) levels in the early postoperative period after CABG. Between April 2009 and January 2010, 95 consecutive patients with sinus rhythm who underwent CABG were evaluated. The patients were divided into two groups according to their postoperative rhythms: sinus rhythm group (SR) and AF group (AF). Demographic, clinical variables, and troponin I were evaluated at the pre- and postoperative times. There were no clinical or demographic differences between the two groups. The postoperative troponin I in the SR group was lower than that in the AF group (0.66 ± 1.62 vs. 2.07 ± 5.01 ng/ml; P = 0.029). Using the receiver operating characteristic curves was found as the best cut-off value to predict AF occurrence at the value of 0.901 ng/ml. Using this value of cTnI, a sensitivity of 60% and a specificity of 87% for AF onset prediction were observed. The cTnI serum levels at the postoperative period after CABG were higher in patients who subsequently developed AF. The cut-off value of 0.901 ng/ml is useful for prediction and preventive therapeutic actions.

Blood mesenchymal stem cell culture from the umbilical cord with and without Ficoll-Paque density gradient method

OBJECTIVES Implantation of cell separation and mesenchymal stem cell culture techniques from human umbilical cord blood with and without using the Ficoll-Paque gradient density method (d=1.077 g/ml). METHODS Ten samples of the umbilical cord blood obtained from full-term deliveries were submitted to two different procedures of mesenchymal stem cell culture: a) Method without the Ficoll-Paque density gradient, which concentrates all nucleated cells; b) Method with the Ficoll-Paque density gradient, which selects only low-density mononuclear cells. Cells were initially plated into 25 cm(2) cultures flasks at a density of 1 x 10(7) nucleated cells/cm(2) and 1 x 10(6) mononuclear cells/cm(2). RESULTS It was obtained 2-13 x 10(7) (median = 2.35 x 10(7)) nucleated cells/cm(2) by the method without the Ficoll-Paque gradient density, and 3.7-15.7 x 10(6) (median = 7.2 x 10(6)) mononuclear cells/cm(2) by the method with the Ficoll-Paque gradient density. In all cultures adherent cells were observed 24 hours after being cultured. Cells presented fibroblastoid and epithelioid morphology. In most of the cultures, cell proliferation occurred in the first week, but after the second week only some cultures - derived from the method without the Ficoll-Paque gradient density-maintained the growth rate reaching confluence. Those cultures were submitted to trypsinization with 0.25% trypsin/EDTA solution and cultured for two to three months. CONCLUSION In the samples analyzed, cell separation and mesenchymal stem cell culture techniques from human umbilical cord blood by the method without the Ficoll-Paque density gradient was more efficient than the method with the Ficoll-Paque density gradient.OBJECTIVES: Implantation of cell separation and mesenchymal stem cell culture techniques from human umbilical cord blood with and without using the Ficoll-Paque gradient density method (d=1.077g/ml). METHODS: Ten samples of the umbilical cord blood obtained from full-term deliveries were submitted to two different procedures of mesenchymal stem cell culture: a) Method without the Ficoll-Paque density gradient, which concentrates all nucleated cells; b) Method with the Ficoll-Paque density gradient, which selects only low-density mononuclear cells. Cells were initially plated into 25 cm2 cultures flasks at a density of 1x107 nucleated cells/cm2 and 1x106 mononuclear cells/cm2. RESULTS: It was obtained 2-13x107 (median = 2.35x107) nucleated cells/cm2 by the method without the Ficoll-Paque gradient density, and 3.7-15.7x106 (median = 7.2x106) mononuclear cells/cm2 by the method with the Ficoll-Paque gradient density. In all cultures adherent cells were observed 24 hours after being cultured. Cells presented fibroblastoid and epithelioid morphology. In most of the cultures, cell proliferation occurred in the first week, but after the second week only some cultures - derived from the method without the Ficoll-Paque gradient density - maintained the growth rate reaching confluence. Those cultures were submitted to trypsinization with 0.25% trypsin/EDTA solution and cultured for two to three months. CONCLUSION: In the samples analyzed, cell separation and mesenchymal stem cell culture techniques from human umbilical cord blood by the method without the Ficoll-Paque density gradient was more efficient than the method with the Ficoll-Paque density gradient.

Avaliação imediata da troponina I cardíaca em pacientes submetidos à revascularização do miocárdio

The present study was developed to determine the early and late prognosis of patients submitted to myocardial revascularization (with or without extracorporeal circulation) and the relationship with troponin-I serum levels at the postoperative period. One hundred and eight patients were studied between December 1996 and December 1997. The serum troponin-I levels were determined by chemoluminescence (Acess - Sanofi-Pasteur) during four periods: preoperative, admission to Intensive Care Unit, first postoperative day and second postoperative day. Values below 0.1 ng/ml were considered normal. Cut-off levels for prognostic evaluation (0.5, 1.0, 2.5 and 5.0 ng/ml) were chosen. Follow-up was measured in months with the aim of construction survival curves. The only event considered was cardiac death. Serum troponin-I had a characteristic early behaviour with higher levels on the first postoperative day. When extracorporeal circulation was utilized (Group I), the levels were significantly higher but there was no correlation with ischemic or perfusion times. Perhaps the troponin-I high serum levels could be due to specific myocardial injury, i. e. coronary artery obstruction, saphenous bypass graft acute failure and so on and not due to extracorporeal circulation per se. It was also possible to determine the cut-off levels as markers of poor prognosis. Serum troponin-I higher than 2.5 ng/ml on the first postoperative day were followed by mortality rates between 33% and 50% up to 6 months of follow-up. Serum troponin-I levels were higher than normal in patients submitted to myocardial revascularization with or without extracorporeal circulation, signifying myocardial cell injury. Values close to 2.5 ng/ml on the first postoperative day alert to the necessity of more aggressive diagnostic and therapeutic measures.

Avaliação ecocardiográfica em pacientes submetidos à substituição de cordas tendíneas rotas

OBJECTIVE: The objective of this study was to evaluate, using echocardiography, the functioning of the mitral valve apparatus in patients submitted to standardized bovine pericardium chordae implantation to substitute ruptured chordae tendineae or elongated chordae with a significant degree of thinning. METHOD: Standardized bovine pericardium chordae were implanted in 23 patients with mitral valve insufficiency due to ruptured or elongated chordae with significant thinning. The ages of the patients varied from 23 to 84 years old (mean 62 years old). The most common cause was fibroelastic degeneration affecting 20 (87.0%) patients. The standardized bovine pericardium chordae were manufactured in sets connected at both ends by two polyester-reinforced rods thereby forming a single block. The bovine pericardium chordae measure 2 mm wide with 3 mm between the chordae. The sets of bovine pericardium chordae are produced in lengths varying from 20 to 35 mm. In 17 (73.9%) patients bovine pericardium chordae were implanted in the posterior cusp and in 6 (26.1%) in the anterior cusp. All the patients were evaluated in the postoperative period by echocardiography after a mean follow-up of six months. RESULTS: The echocardiography in the postoperative period demonstrated an absence of reflux in 11 (47.8%) patients, slight reflux in 8 (34.8%) and slight to moderate reflux in 3 (13.0%). The opening and mobility of the mitral valve was normal in the 22 surviving patients. CONCLUSION: The echocardiography demonstrated good functioning of the mitral valve apparatus in patients submitted to the implantation of standardized bovine pericardium chordae to substitute ruptured chordae tendineae or elongated chordae with a significant degree of thinning.OBJECTIVE The objective of this study was to evaluate, using echocardiography, the functioning of the mitral valve apparatus in patients submitted to standardized bovine pericardium chordae implantation to substitute ruptured chordae tendineae or elongated chordae with a significant degree of thinning. METHOD Standardized bovine pericardium chordae were implanted in 23 patients with mitral valve insufficiency due to ruptured or elongated chordae with significant thinning. The ages of the patients varied from 23 to 84 years old (mean 62 years old). The most common cause was fibroelastic degeneration affecting 20 (87.0%) patients. The standardized bovine pericardium chordae were manufactured in sets connected at both ends by two polyester-reinforced rods thereby forming a single block. The bovine pericardium chordae measure 2 mm wide with 3 mm between the chordae. The sets of bovine pericardium chordae are produced in lengths varying from 20 to 35 mm. In 17 (73.9%) patients bovine pericardium chordae were implanted in the posterior cusp and in 6 (26.1%) in the anterior cusp. All the patients were evaluated in the postoperative period by echocardiography after a mean follow-up of six months. RESULTS The echocardiography in the postoperative period demonstrated an absence of reflux in 11 (47.8%) patients, slight reflux in 8 (34.8%) and slight to moderate reflux in 3 (13.0%). The opening and mobility of the mitral valve was normal in the 22 surviving patients. CONCLUSION The echocardiography demonstrated good functioning of the mitral valve apparatus in patients submitted to the implantation of standardized bovine pericardium chordae to substitute ruptured chordae tendineae or elongated chordae with a significant degree of thinning.

Dynamic cardiomyoplasty: long-term clinical results in patients with dilated cardiomyopathy.

BACKGROUND Dynamic cardiomyoplasty has been considered to be an effective method of surgical treatment of patients with end-stage heart failure, and is an alternative to heart transplantation. METHODS We critically evaluated the long-term course of 52 patients with dilated cardiomyopathy who underwent dynamic cardiomyoplasty and were followed-up for up to 110 months. RESULTS Dilated cardiomyopathy was due to undetermined cause in 42 patients (80.8%), Chagas disease in 8 (15.4%), viral infection in 1 (1.9%), and peripartum cardiomyopathy in 1 (1.9%). In the nonchagasic group the survival rates were 79.5% +/- 6.1%, 67.8% +/- 7.1%, 53.7% +/- 8.3%, 49.9% +/- 8.3%, 14.9% +/- 12.2%, and 14.9% +/- 12.2%, respectively, at 12, 24, 48, 60, 80 and 110 months of follow-up. In the chagasic patients the survival rates were 37.5% +/- 17.1%, 12.5% +/- 11.7%, 12.5% +/- 11.7% and 0%, respectively, at 12, 24, 48, and 60 months of follow-up, making chagasic cardiomyopathy a possible contraindication for dynamic cardiomyoplasty. CONCLUSIONS There was no correlation between the clinical improvement and hemodynamic data. Ventricular fibrillation was a frequent cause of immediate and late death, suggesting the need for prophylactic use of antiarrhythmic drugs or implantable cardioverter/ defibrillators.

Aortic valve replacement using bovine pericardial bioprostheses: 12 years of experience

OBJETIVOS: O presente estudo visa avaliar a evolucao a longo prazo (ate 12 anos de seguimento) de pacientes submetidos a substituicao valvar aortica por bioprotese de pericardio bovino. METODO: De marco 1992 a janeiro 2003, 287 pacientes foram submetidos a substituicao valvar aortica como procedimento isolado, utilizando-se bioprotese de pericardio bovino. Destes, 189 (65,9%) eram do sexo masculino. As idades variaram de 15 a 82 anos com media e desvio padrao de 53,6±15,1 anos e mediana de 56 anos. O diâmetro das bioproteses variou de 21 a 29 mm, sendo que os mais prevalentes foram o de 23 mm (105 casos; 36,6%) e o de 25 mm (outros 105 casos; 36,6%). Apenas um paciente recebeu protese com diâmetro de 29 mm. Os eventos estudados foram sobrevivencia tardia global, sobrevivencia comparativa em pacientes abaixo de 70 anos e com 70 anos ou mais e porcentagem livre de reintervencoes por qualquer causa de disfuncao primaria da bioprotese. A analise dos resultados foi feita com auxilio de curva atuarial Kaplan-Meier. RESULTADOS: A taxa atuarial de sobrevivencia global ao final de 12 anos foi de 91,7±2,2%. A separacao em grupos abaixo de 70 anos (Grupo A= 252 pts) e 70 anos ou mais (Grupo B= 35 pts) mostrou que, no grupo A, a sobrevivencia global foi de 94,7±1,7%, enquanto que no grupo B foi de 58,1±17,2% (Logrank test p= 0,0005; Hazard Ratio 0,20 IC95% 0,01 a 0,29). A taxa livre de reintervencoes por causa primaria da bioprotese foi de 96,1±2,0%, ao final de 12 anos. Os quatro pacientes que apresentaram disfuncao pertenciam ao grupo A, com media de idade de 49,7 anos. CONCLUSOES: O uso da bioprotese de pericardio bovino em portador de doenca valvular aortica proporciona excelente taxa de sobrevivencia apos 12 anos de seguimento. Pacientes com idade igual ou superior a 70 anos apresentaram sobrevivencia significativamente menor, mas as disfuncoes ocorreram exclusivamente no grupo de menor idade.

Risk stratification with troponin I in patients undergoing myocardial revascularization surgery.

OBJECTIVE To determine the immediate behavior and the prognostic value in terms of late survival of serum troponin I measurement in patients undergoing myocardial revascularization surgery with extracorporeal circulation. METHODS We studied 88 random patients, 65 (73.8%) of the male sex, who underwent myocardial revascularization surgery with extracorporeal circulation. Troponin measurements were performed as follows: in the preoperative period, right after intensive care unit admission, and on the first and second postoperative days. Values below 0.1 nanogram per milliliter (ng/mL) were considered normal. The cut points for late prognostic assessment were 0.5 ng/mL; 1 ng/mL; 2.5 ng/mL; and 5 ng/mL. RESULTS The serum troponin I levels were elevated on the first postoperative day, suggesting the occurrence of specific myocardial damage. Patients with a poor prognosis could be identified, because the serum levels above 2.5 ng/mL and 5 ng/mL in the postoperative period resulted, respectively, in mortality rates of 33% and 50% in a maximum 6-month follow-up. CONCLUSION Troponin I values around 2.5 ng/mL in the postoperative period should call attention to the need for more aggressive diagnostic or therapeutical measures.

Estudo da função ventricular na técnica de plicatura da parede livre do ventrículo esquerdo em cães

OBJECTIVE: We tested a new surgical technique, the plication of the left ventricular free wall, to reduce left ventricular area and volume and improve left ventricular systolic function, without using a cardiopulmonary bypass. METHODS: Dilated cardiomyopathy was induced in eight dogs by the injection of doxorubicin. Plication of the left ventricular free wall was performed in four dogs with induced cardiomyopathy and in five control dogs. Two dogs not submitted to surgery. The other two dogs died during the induction phase. Cardiac output, 2-dimensional and M-mode echocardiography, arterial blood pressure and electrocardiography were recorded over a 180 days period. Ambulatory electrocardiography of 24 hours was performed during the first postoperative day. RESULTS: The cardiomyopathy-induced group had significant improvements in cardiac output, ejection fraction, shortening fraction and reductions in the left ventricular end-systolic, end-diastolic area and volume after the surgery. One dog died. Electrocardiography and Holter revealed premature ventricular complexes, which improved spontaneously at the first week. The cardiomyopathy-induced dogs that did notundergo surgery deteriored and died about 40 days after the induction of cardiomyopathy. Hemodynamic values did not change in the normal dogs submitted to the surgery. CONCLUSION: The plication of the left ventricular free wall reduced the left ventricular area and volume and improved left ventricular systolic function in dogs with doxorubicin-induced cardiomyopathy giving low morbidity and mortality.

Reconstituição da valva pulmonar e via de saída do ventrículo direito, com prótese bivalvular e prótese tubular valvada de tronco pulmonar de porco: estudo experimental e aplicação clínica

Obstruction of the right ventricle outlet tract (RVOT) has been the object of arguments regarding its surgical correction, while there are different criteria for reconstruction. Thus two kinds of prostheses were developed from the pig pulmonary trunk (PT). 1) One with two valves of the pulmonary valve (PV), named bivalvular graft, and could be used for correction of Fallot with pulmonary ring hypoplasia. 2) The other, with a tubular form, containing the pig PV itself and named valved conduit, could be used in RVOT reconstruction for patients with pulmonary atresia (PA). These prostheses were tested in an experimental model: implant of the bivalvular graft was performed in 16 sheep with the aid of extracorporeal circulation (ECC). The surgical technique consisted of resection of the two valves of the PV and of the anterior wall of the infundibulum; this condition was similar to Fallot correction. Implant of the valvular conduit was carried out in 12 sheep, without ECC, by direct clamping of the RV infundibulum. The PT was then ligated, deviating blood flow through the conduit. Intraoperative hemodynamics and echodoppler evaluation of the bivalvular graft showed good PV competence and only 1 case of gradient higher than 10 mmHg. Because of frequent pulmonary hemorrhage followed by death due to ECC, this group was not evaluated in the postoperative period. Intraoperative hemodynamic measurements of the valvular conduit were carried out showing good valvular competence and gradient higher than 10 mmHg in 3 cases. There was no operative mortality. Seven sheeps were followed-up during the late postoperative period with a control echodoppler on days 99 and 135 of follow-up. Gradients ranged from 9.85 to 49 mmHg (mean = 19.7). Four sheep underwent hemodynamic studies at six months of follow-up. There was a slight increase in the gradient between RV and PT (mean = 22.3 mmHg), no gradient being observed inside the conduit. Anatomopathological evaluation was performed. Clinical applications of the bivalvular prostheses was performed in 3 patients with tetralogy of Fallot and hypoplasia of the pulmonary ring (2 cases) and PV absent (1 case); they were 16,2 and 7 years old. The postoperative echodopplercardiogram showed gradients between 10 to 20 mmHg and mild pulmonary valve insufficiency. Clinical application of the valvular conduit was performed in 2 patients: 1 with pulmonary atresia and ventricular septal defect (VSD), the other with corrected transposition of the great arteries, VSD and subpulmonary stenosis (10 and 6 years old, respectively). The postoperative echodopplercardiogram showed gradients between 15 to 18 mmHg. Although the results of the experiment may be considered acceptable, reconstruction of the RVOT with the newly developed prostheses, obviously requires to be tested over time to better evaluate their resistance to calcification, infection, obstruction and rupture.