Laser Doppler anemometry measurements of steady flow through two bi-leaflet prosthetic heart valves / Velocimetria laser de escoamento permanente através de duas próteses cardíacas de duplo folheto

INTRODUCTION: In vitro hydrodynamic characterization of prosthetic heart valves provides important information regarding their operation, especially if performed by noninvasive techniques of anemometry. Once velocity profiles for each valve are provided, it is possible to compare them in terms of hydrodynamic performance. In this first experimental study using laser doppler anemometry with mechanical valves, the simulations were performed at a steady flow workbench. OBJECTIVE: To compare unidimensional velocity profiles at the central plane of two bi-leaflet aortic prosthesis from St. Jude (AGN 21 - 751 and 21 AJ - 501 models) exposed to a steady flow regime, on four distinct sections, three downstream and one upstream. METHODS: To provide similar conditions for the flow through each prosthesis by a steady flow workbench (water, flow rate of 17L/min.) and, for the same sections and sweeps, to obtain the velocity profiles of each heart valve by unidimensional measurements. RESULTS: It was found that higher velocities correspond to the prosthesis with smaller inner diameter and instabilities of flow are larger as the section of interest is closer to the valve. Regions of recirculation, stagnation of flow, low pressure, and flow peak velocities were also found. CONCLUSIONS: Considering the hydrodynamic aspect and for every section measured, it could be concluded that the prosthesis model AGN 21 - 751 (RegentTM) is superior to the 21 AJ - 501 model (Master Series). Based on the results, future studies can choose to focus on specific regions of the these valves.

INTRODUÇÃO: A caracterização hidrodinâmica in vitro de próteses de válvulas cardíacas fornece informações importantes quanto ao seu funcionamento, sobretudo se realizada por meio de métodos não-invasivos de anemometria. Uma vez obtidos os perfis de velocidade para cada válvula, é possível compará-las quanto ao seu desempenho hidrodinâmico. Neste primeiro estudo experimental de anemometria laser com válvulas mecânicas, as simulações foram realizadas em bancada de testes para escoamento permanente. OBJETIVO: Comparar perfis de velocidade unidimensional no plano central de duas próteses aórticas de duplo folheto St. Jude (modelos AGN 21 - 751 e 21 AJ - 501) submetidas a um regime de fluxo permanente, para quatro seções distintas, três à jusante e uma à montante. MÉTODOS: Proporcionar condições de similaridade para o escoamento através de cada prótese, por meio de bancada hidrodinâmica para escoamento permanente (água, à vazão de 17 L/min.) e, por meio de anemometria laser unidimensional, obter os perfis de velocidades para as mesmas seções e varreduras. RESULTADOS: Verificou-se que as maiores velocidades correspondem à prótese de diâmetro interno menor e que as instabilidades do fluxo são maiores à medida que a seção de interesse encontra-se mais próxima da válvula. Também foram verificadas as regiões de recirculação, de estagnação do fluxo e de baixa pressão, além dos picos de velocidade para o escoamento em questão. CONCLUSÕES: Sob o aspecto hidrodinâmico e para todas as seções de interesse, foi possível concluir a preferência da válvula de modelo AGN 21 - 751 (RegentTM) sobre a 21 AJ - 501 (Master Series). Os resultados obtidos permitiram escolher, para os próximos trabalhos, um foco de estudo mais específico para regiões concretas dessas próteses.

Laser Doppler anemometry measurements of steady flow through two bi-leaflet prosthetic heart valves.

INTRODUCTION: In vitro hydrodynamic characterization of prosthetic heart valves provides important information regarding their operation, especially if performed by noninvasive techniques of anemometry. Once velocity profiles for each valve are provided, it is possible to compare them in terms of hydrodynamic performance. In this first experimental study using laser doppler anemometry with mechanical valves, the simulations were performed at a steady flow workbench. OBJECTIVE: To compare unidimensional velocity profiles at the central plane of two bi-leaflet aortic prosthesis from St. Jude (AGN 21 - 751 and 21 AJ - 501 models) exposed to a steady flow regime, on four distinct sections, three downstream and one upstream. METHODS: To provide similar conditions for the flow through each prosthesis by a steady flow workbench (water, flow rate of 17L/min.) and, for the same sections and sweeps, to obtain the velocity profiles of each heart valve by unidimensional measurements. RESULTS: It was found that higher velocities correspond to the prosthesis with smaller inner diameter and instabilities of flow are larger as the section of interest is closer to the valve. Regions of recirculation, stagnation of flow, low pressure, and flow peak velocities were also found. CONCLUSIONS: Considering the hydrodynamic aspect and for every section measured, it could be concluded that the prosthesis model AGN 21 - 751 (RegentTM) is superior to the 21 AJ - 501 model (Master Series). Based on the results, future studies can choose to focus on specific regions of the these valves.

Erythropoietin protects the systolic function of neonatal hearts against ischaemia/reperfusion injury.

OBJECTIVES: The effect of erythropoietin (EPO) on neonatal hearts is not well understood. The current hypothesis is that EPO has protective effects against ischaemia-reperfusion when administered prior to ischaemia induction. METHODS: Systolic and diastolic indices, as well as the Akt and extracellular-regulated kinase (Erk) signalling pathways, were studied in vivo using a neonatal pig heart model. Regional ischaemia was induced for 45 min by the ligation of the left anterior descending artery, followed by 90 min of reperfusion. The treatment groups consisted of: (i) untreated controls, (ii) treatment with EPO 3 min prior to ischaemia and (iii) treatment with EPO 24 h before ischaemia. Sophisticated myocardial contractility indices were assessed by pressure/volume loops of the left ventricle. The Akt and Erk pathways were evaluated via a western blot. RESULTS: Elastance was found to be higher in the group receiving EPO 3 min prior to ischaemia. In addition, preload recruitable stroke work was higher for both groups receiving EPO prior to ischaemia when compared with controls. The time constant of the isovolumic relaxation and end-diastolic pressure-volume relationship did not differ between the three groups after 90 min of reperfusion. Furthermore, EPO treatment enhanced phosphorylation of Akt, but not Erk, and EPO-treated animals showed lower levels of apoptosis-related proteins. CONCLUSIONS: EPO had a protective effect on neonatal systolic function after ischaemia/reperfusion injury, but no effect on diastolic function. This cardioprotective effect might be mediated by the activation of the Akt pathway.

Hemólise na circulação extracorpórea: correlação com tempo e procedimentos realizados / Hemolysis in extracorporeal circulation: relationship between time and procedures

INTRODUÇÃO: A circulação extracorpórea (CEC) é indispensável para a maioria das operações cardíacas, mas causa danos significantes ao sangue, dentre eles a hemólise. OBJETIVO: Quantificar as taxas de hemólise em diferentes tempos nas operações para revascularização do miocárdio com uso de CEC. MÉTODOS: Foram medidas as taxas de hemólise de 22 pacientes em 6 tempos distintos durante a revascularização do miocárdio com uso de CEC: T0 - antes do início da CEC, T1 - 5 minutos após o início da CEC, T2 - com 30 minutos de CEC, T3 - imediatamente antes do despinçamento da aorta, T4 - imediatamente antes da passagem do volume residual para o paciente e T5 - 5 minutos após o término da passagem do volume residual para o paciente. Foram calculadas as taxas de hemólise entre os intervalos de tempo: T0-T1; T1-T2; T2-T3; T3-T4 e T4-T5. RESULTADOS: Os primeiros 5 minutos após a CEC demonstraram maior taxa de hemólise (P = 0,0003) em comparação às outras taxas calculadas, representando 29% da hemólise total até T4 (imediatamente antes da passagem do volume residual para o paciente). CONCLUSÃO: Não foram observadas variações significantes nas taxas de hemólise durante a aspiração na raiz da aorta (P > 0,38) nem com o procedimento utilizado para a passagem do volume residual de sangue no circuito para os pacientes.

INTRODUCTION: Extracorporeal circulation (EC) is very important in cardiac surgery but causes significant damage to the blood, including hemolysis. OBJECTIVE: To quantify the rate of hemolysis at different times during EC in elective coronary artery bypass grafting. METHODS: We measured rates of hemolysis of 22 patients at 6 different times during myocardial revascularization during EC: T0 - before the start of EC, T1 - five minutes after of the EC initiation, T2 - 30 minutes of EC, T3 - immediately before the aortic unclamping, T4 - immediately before passage of the residual volume to the patient and T5 - five minutes after the passage of the residual volume to the patient. Rates of hemolysis were calculated between the intervals of time: T0-T1; T1-T2; T2-T3; T3-T4 and T4-T5. RESULTS: The first 5 minutes after the EC showed the highest rate of hemolysis (P = 0.0003) compared to the others calculated rates, representing 29% of the total haemolysis until T4 (Immediately before passage of the residual volume to the patient). CONCLUSION: There were no significant changes in the rate of hemolysis during the suction in the aortic root (P> 0.38), nor with the procedure used for the passage of the residual volume of blood in the circuit to the patient.

Role of echocardiography in the ventricular assessment of the transplanted heart versus heart rejection.

BACKGROUND: Heart transplantation is an alternative for individuals with end-stage heart disease. However, episodes of heart rejection (HR) are frequent and increase morbidity and mortality, requiring the use of an accurate non-invasive exam for their diagnosis, since endomyocardial biopsy (EMB) is not a complication-free procedure. OBJECTIVE: To compare the parameters obtained by use of Doppler echocardiography in a group of transplanted patients with HR (TX1) and another group of transplanted patients without rejection (TX0), having as reference a control group (CG) and observing the behavior of the left ventricular systo-diastolic function expressed as the myocardial performance index (MPI) METHODS: Transthoracic echocardiographies were performed from January 2006 to January 2008 to prospectively assess 47 patients divided into three groups: CG (36.2%); TX0 (38.3%); and TX1 (25.5%). The MPI was compared between the groups, and data were analyzed by use of Fisher exact test and nonparametric Kruskal-Wallis test, both with significance level of 5%. RESULTS: The groups did not differ regarding age, weight, height, and body surface. When compared to GC, TX0 and TX1 showed a change in the left ventricular systo-diastolic function, expressed as an increase in MPI, which was greater in TX1 [0.38 (0.29 - 0.44); 0.47 (0.43 - 0.56); 0.58 (0.52 - 0.74), respectively; p < 0.001]. CONCLUSION: Echocardiography was a very accurate test to detect changes in the systo-diastolic function of the transplanted heart; however, it did not prove to be reliable to replace BEM in the safe diagnosis of HR.

Papel do ecocardiograma na avaliação ventricular do coração transplantado versus rejeição cardíaca / Role of echocardiography in the ventricular assessment of the transplanted heart versus heart rejection

FUNDAMENTO: O Transplante Cardíaco (TC) é uma alternativa para os indivíduos com doença cardíaca terminal. Na evolução pós-transplante, a ocorrência de episódios de Rejeição Cardíaca (RC) é evento frequente que aumenta a morbimortalidade, sendo necessário o emprego de exame não invasivo com boa acurácia para seu diagnóstico, pois a Biópsia Endomiocárdica (BEM) não é um procedimento isento de complicações. OBJETIVO: Comparar parâmetros obtidos com o princípio Doppler, entre os pacientes transplantados com RC (TX1) e os pacientes transplantados sem rejeição (TX0); utilizando como referência o Grupo Controle (GC) e observando o comportamento da função sistodiastólica ventricular esquerda expressa por meio do Índice de Performance Miocárdica (IPM). MÉTODOS: Foram realizados ecocardiogramas transtorácicos no período de janeiro de 2006 a janeiro de 2008, para a avaliação prospectiva de 47 pacientes, subdivididos em GC (36,2%), TX0 (38,3%) e TX1 (25,5%), comparando-se o IPM entre eles. Para a análise dos dados foram realizados os testes exato de Fisher e o não paramétrico de Kruskal-Wallis, ambos com nível de significância de 5%. RESULTADOS: Os grupos não diferiram em relação a idade, peso, altura e superfície corpórea. Quando comparado ao GC, TX0 e TX1 apresentaram alteração da função sistodiastólica ventricular esquerda, expressa como aumento do IPM, que foi mais intenso no TX1 [0,38 (0,29 - 0,44) X 0,47 (0,43 - 0,56) X 0,58 (0,52 - 0,74) p < 0,001]. CONCLUSÃO: O ecocardiograma mostrou-se como exame de boa acurácia na detecção das alterações da função sistodiastólica do coração transplantado; entretanto, não foi confiável como método substituto da BEM para o diagnóstico seguro de RC.

BACKGROUND: Heart transplantation is an alternative for individuals with end-stage heart disease. However, episodes of heart rejection (HR) are frequent and increase morbidity and mortality, requiring the use of an accurate non-invasive exam for their diagnosis, since endomyocardial biopsy (EMB) is not a complication-free procedure. OBJECTIVE: To compare the parameters obtained by use of Doppler echocardiography in a group of transplanted patients with HR (TX1) and another group of transplanted patients without rejection (TX0), having as reference a control group (CG) and observing the behavior of the left ventricular systo-diastolic function expressed as the myocardial performance index (MPI) METHODS: Transthoracic echocardiographies were performed from January 2006 to January 2008 to prospectively assess 47 patients divided into three groups: CG (36.2%); TX0 (38.3%); and TX1 (25.5%). The MPI was compared between the groups, and data were analyzed by use of Fisher exact test and nonparametric Kruskal-Wallis test, both with significance level of 5%. RESULTS: The groups did not differ regarding age, weight, height, and body surface. When compared to GC, TX0 and TX1 showed a change in the left ventricular systo-diastolic function, expressed as an increase in MPI, which was greater in TX1 [0.38 (0.29 - 0.44); 0.47 (0.43 - 0.56); 0.58 (0.52 - 0.74), respectively; p < 0.001]. CONCLUSION: Echocardiography was a very accurate test to detect changes in the systo-diastolic function of the transplanted heart; however, it did not prove to be reliable to replace BEM in the safe diagnosis of HR.

Fatores associados à sobrevida em pacientes submetidos a transplante cardíaco utilizando microcardioplegia sanguínea retrógrada / Associated factors with survivals in patients undergoing orthotopic heart transplant using retrograde blood microcardioplegia

INTRODUÇÃO: Uma grande variedade de técnicas e soluções é utilizada na preservação do coração durante o transplante, o que demonstra a falta de método ideal na prática clínica. A administração da cardioplegia de forma retrógrada propicia perfusão contínua, o que pode conferir melhor recuperação inicial do coração transplantado. O objetivo deste trabalho é descrever a experiência de um único centro onde todos os pacientes receberam a mesma solução de conservação de órgão e foram submetidos a microcardioplegia sanguínea retrógrada contínua durante o implante do enxerto e avaliar fatores de mortalidade precoce e tardia com a utilização desta técnica. MÉTODOS: Este é um estudo retrospectivo, observacional e descritivo, realizado em um único centro. RESULTADOS: No período do estudo, foram realizados 35 transplantes cardíacos, sendo que 15 (42,9%) pacientes encontravam-se em choque cardiogênico. A probabilidade de sobrevida foi 74,8±7,8%, 60,4±11,3% e 15,1±13,4% ao final de 1 ano, 5 anos e 10 anos de seguimento, respectivamente. O tempo médio de sobrevida foi de 96,6 meses. CONCLUSÃO: A utilização da solução cardioplégica para proteção de órgãos e a estratégia de iniciar a perfusão com microcardioplegia sanguínea retrógrada contínua forneceu proteção adequada.

BACKGROUND: Several techniques and cardioplegic solutions have been used for heart preservation during transplant procedures. Unfortunately, there is a lack of ideal method for myocardial preservation in the clinical practice. The use of retrograde cardioplegia provides continuous infusion of cardioplegic solution during the graft implantation. This strategy may provide better initial recovery of the graft. The objective of this study is to describe the experience of a single center where all patients received the same solution for organ preservation and were subjected to continuous retrograde blood microcardioplegia during implantation of the graft and to evaluate factors associated to early and late mortality with this technique. METHODS: This is a retrospective, observational and descriptive study of a single center. RESULTS: During the study period were performed 35 heart transplants. Fifteen (42.9%) patients were in cardiogenic shock. The probability of survival was 74.8±7.8%, 60.4±11.3% and 15.1±13.4% at 1 year, 5 years and 10 years of follow-up, respectively. The median survival time was 96.6 months. CONCLUSION: The use of myocardial protection with retrograde cardioplegic solution may reduce the risks associated morbidity due to cold ischemia time during the heart transplant, and we suggest that this benefit may be even greater in cases of cold ischemia time longer ensuring protection to the myocardium.

The effect on hemolysis of the raceway profile of roller pumps used in cardiopulmonary bypass.

This study aims at the influence on hemolysis of the differences between the maximum and minimum amplitudes of pressure in the outlet of three roller pump models adjusted by dynamic calibration method. Tests were performed with silicone tubes (½ × (3)/(16) inches) in fluid analogous to blood and fresh bovine blood from slaughterhouse. Tests with analogous solution to blood were performed varying the dynamic calibration pressure between 78 and 500 mm Hg. Tests with fresh bovine blood were performed with the three pumps simultaneously, and pressure differences and free hemoglobin in the plasma were measured during 360 minutes. Tests with both analogous solution to blood and fresh bovine blood showed differences of mean pressures of pump 2 related to pumps 1 and 3 (p < 0.01). The different models of roller pumps analyzed presented differences in pressure amplitudes (p < 0.01) and hemolysis (p < 0.01) adjusted for the same dynamic calibration pressure. Raceway profile of pump 2 resulted in smaller pressure amplitude, implying lower hemolysis rate compared with pumps 1 and 3.

Associated factors with survivals in patients undergoing orthotopic heart transplant using retrograde blood microcardioplegia.

BACKGROUND: Several techniques and cardioplegic solutions have been used for heart preservation during transplant procedures. Unfortunately, there is a lack of ideal method for myocardial preservation in the clinical practice. The use of retrograde cardioplegia provides continuous infusion of cardioplegic solution during the graft implantation. This strategy may provide better initial recovery of the graft. The objective of this study is to describe the experience of a single center where all patients received the same solution for organ preservation and were subjected to continuous retrograde blood microcardioplegia during implantation of the graft and to evaluate factors associated to early and late mortality with this technique. METHODS: This is a retrospective, observational and descriptive study of a single center. RESULTS: During the study period were performed 35 heart transplants. Fifteen (42.9%) patients were in cardiogenic shock. The probability of survival was 74.8±7.8%, 60.4±11.3% and 15.1±13.4% at 1 year, 5 years and 10 years of follow-up, respectively. The median survival time was 96.6 months. CONCLUSION: The use of myocardial protection with retrograde cardioplegic solution may reduce the risks associated morbidity due to cold ischemia time during the heart transplant, and we suggest that this benefit may be even greater in cases of cold ischemia time longer ensuring protection to the myocardium.

Hemolysis in extracorporeal circulation: relationship between time and procedures.

INTRODUCTION: Extracorporeal circulation (EC) is very important in cardiac surgery but causes significant damage to the blood, including hemolysis. OBJECTIVE: To quantify the rate of hemolysis at different times during EC in elective coronary artery bypass grafting. METHODS: We measured rates of hemolysis of 22 patients at 6 different times during myocardial revascularization during EC: T0 - before the start of EC, T1 - five minutes after of the EC initiation, T2 - 30 minutes of EC, T3 - immediately before the aortic unclamping, T4 - immediately before passage of the residual volume to the patient and T5 - five minutes after the passage of the residual volume to the patient. Rates of hemolysis were calculated between the intervals of time: T0-T1; T1-T2; T2-T3; T3-T4 and T4-T5. RESULTS: The first 5 minutes after the EC showed the highest rate of hemolysis (P = 0.0003) compared to the others calculated rates, representing 29% of the total haemolysis until T4 (Immediately before passage of the residual volume to the patient). CONCLUSION: There were no significant changes in the rate of hemolysis during the suction in the aortic root (P> 0.38), nor with the procedure used for the passage of the residual volume of blood in the circuit to the patient.

Resultados tardios da plastia mitral em pacientes reumáticos / Late outcomes of mitral repair in rheumatic patients

INTRODUÇÃO: Os resultados tardios da plastia mitral em pacientes reumáticos são controversos na literatura. OBJETIVO: Estudo observacional e prospectivo que avalia os resultados tardios e identifica os fatores associados à reoperação e à mortalidade em pacientes reumáticos submetidos à plastia da valva mitral. MÉTODOS: Incluídos somente os pacientes com valvopatia mitral reumática submetidos a plastia, com insuficiência tricúspide associada ou não. Excluídos os pacientes com outros procedimentos associados. Um total de 104 pacientes foi estudado. Sobrevida e reoperação foram avaliadas pela analise de Kaplan-Meier e regressão logística de Cox. RESULTADOS: O tempo de seguimento foi de 63 ± 39 meses (IC 95 por cento 36 a 74 meses). A classe funcional III e IV estava presente em 65,4 por cento dos pacientes no pré-operatório. Foram realizadas 33 plastias do anel posterior, 21 comissurotomias, 50 comissurotomias e plastias do anel posterior. Não houve mortalidade operatória e a tardia foi de três (2,8 por cento) pacientes. A reoperação tardia esteve associada à insuficiência mitral residual no pós-operatório (P<0,001), presença de hipertensão pulmonar no pré-operatório (P< 0,01), idade (P<0,04) e classe funcional no pós-operatório (P<0,001). No seguimento, a probabilidade de estar livre de reoperação com 5 e 10 anos foi de 91,2 ± 3,4 por cento e 71,1 ± 9,2 por cento, respectivamente. CONCLUSÃO: Os resultados tardios do reparo da valva mitral em pacientes reumáticos têm fatores associados à reoperação. O reparo da valva mitral reumática é seguro e com ótima sobrevida a longo prazo.

INTRODUCTION AND AIMS: The long-term results after surgical repair of rheumatic mitral valve remain controversial in literature. Our aim was to determine the predictive factors which impact the long-term results after isolated rheumatic mitral valve repair and to evaluate the effect of those factors on reoperation and late mortality. METHODS: One hundred and four patients with rheumatic valve disease who had undergone mitral valve repair with or without tricuspid valve annuloplasty were included. All patients with associated procedures were excluded. The predictive variables for reoperation were assessed with Cox regression and Kaplan Meier survival curves. RESULTS: The mean follow-up time was 63 ± 39 months (CI 95 percent 36 to 74 months). The functional class III and IV was observed in 65.4 percent of all patients. The posterior ring annuloplasty was performed in 33 cases, comissutoromy in 21 cases, and comissurotomy with posterior ring annuloplasty in 50 patients. There was no operative mortality. The late mortality was 2.8 percent (three patients). The late reoperation was associated with residual mitral valve regurgitation after surgery (P<0.001), pulmonary hypertension at the pre-operative time (P<0.001), age (P<0.04) and functional class at the post-operative time (P<0.001). We observed freedom from reoperation rates at 5 and 10 years of 91.2 ± 3.4 percent and 71.1 ± 9.2 percent, respectively. CONCLUSION: Repair of mitral valve in rheumatic valve disease is feasible with good long-term outcomes. Preoperative pulmonary hypertension, residual mitral valve regurgitation after surgery, age and functional class are predictors of late reoperation.

A bovine pericardium rigid prosthesis for left ventricle restoration: 12 years of follow-up.

BACKGROUND: Myocardial infarction might result in dilated left ventricle and numerous techniques have been described to restore the original left ventricle shape and identify tools for late survival assessment. The aim of this study is to compare our experience with a modified Dor procedure using a rigid prosthesis to the septal anterior ventricular exclusion procedure (SAVE) for left ventricle restoration. The EuroScore index for prediction of late follow up survival was evaluated. METHODS: We evaluated 80 patients who underwent left ventricle restoration between 1999 to 2007 and eight patients were excluded with incomplete data. A modified Dor procedure with rigid prosthesis (MD group) was performed on 53 patients and 19 underwent the septal anterior ventricular exclusion procedure (SAVE group). The patients were classified according their left ventricle shape as type I, II or III. Kaplan-Meier and Cox proportional hazard ratio regressions analysis were performed to assess survival after both techniques and expected surgical mortality using EuroScore index ranking after 12 years of follow up. RESULTS: The operative mortality was comparable in both groups ranked by EuroScore index. The groups were comparable for all clinical data, except the MD group had more patients using intra-aortic balloon pumps before surgery, (5.7% vs. 0; P<0.01). Kaplan Meier analysis by left ventricle shape showed comparable survival for all patients, with slightly higher survival for type I. Kaplan Meier analysis of all death showed equivalent survival curves for both techniques after 12 years of follow up (71.5 ± 12.3 vs. 46.6 ± 20.5 years; P=0.08). Kaplan Meier analysis of EuroScore index for all patients showed a difference between the three ranked categories, i.e., 0 to 10%, 11 to 49% and higher than 50% expected surgical mortality after 12 years of follow up (70.9 ± 16.2 vs. 67.5 ± 12.7 vs. 53.0 ± 15.5; P=0.003). CONCLUSION: The MD procedure showed consistent ejection fraction improvements after long term follow up. Survival was comparable for all ventricular types and for the MD and SAVE procedures. The EuroScore index is a useful index for late survival assessment of ventricular restoration techniques.

Brazilian perfusionists and arterial roller pump adjustment: comparison between static and dynamic calibration method.

INTRODUCTION: Roller pumps play an important role in extracorporeal circulation. However, occlusion of the rollers should be adequately performed and this can be adjusted mainly by two methods: static and dynamic. OBJECTIVE: To investigate how the Brazilian perfusionists adjust arterial roller pumps in their services and evaluate the application of a Device to Assist Calibration (DAC) that facilitates roller adjustment by the dynamic calibration method. METHODS: We installed a roller pump with accessories to perform adjustment by drop rate (static calibration) and dynamic calibration methods during the XXVIII Brazilian Congress of Extracorporeal Circulation. Perfusionists were asked to adjust the roller pump according to the procedure they usually do in their service. After each adjustment pressure was measured by dynamic calibration method with DAC. The research was approved by the Research Ethics Committee of UNICAMP, Nº 1144/2010. RESULTS: There were 56 perfusionists in this study. Pressure average of 56 measurements of dynamic calibration was 434 ± 214 mmHg; 76% of measurements were within the recommended range for the use of the dynamic calibration method (between 150 and 500 mmHg). CONCLUSION: Brazilian perfusionists tend to adjust roller pumps with less occlusive settings. The amplitudes of the dynamic calibration pressure tend to be smaller for more experienced perfusionists because their skills increase with time. The device can be used by the perfusionist to adjust roller pumps with greater accuracy and mainly repeatability in few minutes.

A bovine pericardium rigid prosthesis for left ventricle restoration: 12 years of follow-up / Prótese rígida de pericárdio bovino para remodelamento ventricular esquerdo: 12 anos de seguimento

BACKGROUND: Myocardial infarction might result in dilated left ventricle and numerous techniques have been described to restore the original left ventricle shape and identify tools for late survival assessment. The aim of this study is to compare our experience with a modified Dor procedure using a rigid prosthesis to the septal anterior ventricular exclusion procedure (SAVE) for left ventricle restoration. The EuroScore index for prediction of late follow up survival was evaluated. METHODS: We evaluated 80 patients who underwent left ventricle restoration between 1999 to 2007 and eight patients were excluded with incomplete data. A modified Dor procedure with rigid prosthesis (MD group) was performed on 53 patients and 19 underwent the septal anterior ventricular exclusion procedure (SAVE group). The patients were classified according their left ventricle shape as type I, II or III. Kaplan-Meier and Cox proportional hazard ratio regressions analysis were performed to assess survival after both techniques and expected surgical mortality using EuroScore index ranking after 12 years of follow up. RESULTS: The operative mortality was comparable in both groups ranked by EuroScore index. The groups were comparable for all clinical data, except the MD group had more patients using intra-aortic balloon pumps before surgery, (5.7 percent vs. 0; P<0.01). Kaplan Meier analysis by left ventricle shape showed comparable survival for all patients, with slightly higher survival for type I. Kaplan Meier analysis of all death showed equivalent survival curves for both techniques after 12 years of follow up (71.5 ± 12.3 vs. 46.6 ±20.5 years; P=0.08). Kaplan Meier analysis of EuroScore index for all patients showed a difference between the three ranked categories, i.e., 0 to 10 percent, 11 to 49 percent and higher than 50 percent expected surgical mortality after 12 years of follow up (70.9 ± 16.2 vs. 67.5 ± 12.7 vs. 53.0 ± 15.5; P=0.003). CONCLUSION: The MD procedure showed consistent ejection fraction improvements after long term follow up. Survival was comparable for all ventricular types and for the MD and SAVE procedures. The EuroScore index is a useful index for late survival assessment of ventricular restoration techniques.

INTRODUÇÃO: O infarto do miocárdio pode levar à dilatação do ventrículo esquerdo e numerosas técnicas têm sido descritas para remodelar o ventrículo ao seu formato original. O objetivo deste estudo foi comparar nossa experiência com a cirurgia de Dor modificada, usando prótese rígida, com a técnica de exclusão septal ventricular anterior (SAVE). Foi avaliado também o EuroScore como índice preditivo da mortalidade tardia. MÉTODOS: Avaliamos 80 pacientes que foram submetidos a remodelamento ventricular entre 1997 e 2007. Oito pacientes foram excluídos por dados incompletos. A cirurgia de Dor modificada (grupo MD) foi constituída por 53 pacientes e 19 no grupo com exclusão septal anterior (grupo SAVE). Os pacientes foram classificados de acordo com o formato do ventrículo como tipo I, II ou III. Curvas de sobrevivência de Kaplan-Meier e regressão de Cox foram utilizadas para analisar a sobrevida nas duas técnicas e a mortalidade esperada foi avaliada utilizando o EuroScore para a mortalidade operatória e após 12 anos de seguimento. RESULTADOS: A mortalidade operatória foi comparável nos dois grupos quando avaliados pelo EuroScore. Os grupos foram comparáveis quanto a dados clínicos, com exceção, que o grupo MD apresentava maior número de pacientes com balão intra-aórtico no pré-operatório (5,7 por cento vs. 0; P<0,01). A curva actuarial considerando o formato dos ventrículos foi comparável avaliando-se todos os pacientes, sendo que o formato tipo I apresentou discreta melhor sobrevida após 12 anos de seguimento. As técnicas MD e SAVE demonstraram sobrevidas semelhantes após 12 anos de seguimento (71,5 ± 12,3 vs. 46,6 ±20,5 por cento; P=0,08). Avaliando o EuroScore para todos os pacientes, observamos que nas categorias utilizadas, ou seja, 0-10 por cento; 11-49 por cento e maior que 50 por cento de mortalidade esperada, a sobrevida após 12 anos de seguimento foi diferente (70,9 ± 16,2 vs. 67,5 ± 12,7 vs. 53,0 ± 15,5; P=0,003). CONCLUSÃO: A técnica MD demonstrou melhora consistente da fração de ejeção no seguimento tardio. As duas técnicas apresentaram sobrevida comparáveis. O EuroScore pode ser um índice útil para avaliação da sobrevida tardia.

Os perfusionistas Brasileiros e o ajuste do rolete arterial: comparação entre a calibração estática e dinâmica / Brazilian perfusionists and arterial roller pump adjustment: comparison between static and dynamic calibration method

INTRODUÇÃO: Bombas de roletes desempenham um papel importante na circulação extracorpórea. No entanto, a oclusão dos roletes das bombas deve ser realizada de forma adequada e estas podem ser ajustadas, principalmente por dois métodos: estático e dinâmico. OBJETIVO: Investigar como os perfusionistas brasileiros ajustam as bombas de rolete arterial em seus serviços e testar o uso de um Dispositivo Auxiliar de Calibração que facilita o ajuste pelo método de calibração dinâmica. MÉTODOS: Foi instalada uma bomba de roletes com os acessórios necessários para a realização de sua calibração pelos métodos de velocidade de queda (calibração estática) e calibração dinâmica durante o XXVIII Congresso Brasileiro de Circulação Extracorpórea. Foi solicitado aos perfusionistas que ajustassem uma bomba de roletes conforme procedimento normalmente utilizado em seu serviço. Após cada regulagem, foi medida a respectiva pressão pelo método de calibração dinâmica com o auxílio do dispositivo. O projeto foi aprovado pelo Comitê de Ética em Pesquisa da UNICAMP, sob Nº 1144/2010. RESULTADOS: Participaram da pesquisa 56 perfusionistas. A média das 56 medidas de pressão de calibração dinâmica foi 434 ± 214 mmHg; 76 por cento das medidas realizadas ficaram no intervalo preconizado para o uso da técnica de calibração dinâmica (entre 150 e 500 mmHg). CONCLUSÃO: Os perfusionistas brasileiros tendem a calibrar bombas de roletes com ajustes menos oclusivos. As amplitudes das medidas de pressão de calibração dinâmica tendem a ser menores para perfusionistas mais experientes. O dispositivo pode ser utilizado por perfusionistas para ajustar bombas de roletes com maior precisão e, principalmente, repetitividade e em alguns minutos.

INTRODUCTION: Roller pumps play an important role in extracorporeal circulation. However, occlusion of the rollers should be adequately performed and this can be adjusted mainly by two methods: static and dynamic. OBJECTIVE: To investigate how the Brazilian perfusionists adjust arterial roller pumps in their services and evaluate the application of a Device to Assist Calibration (DAC) that facilitates roller adjustment by the dynamic calibration method. METHODS: We installed a roller pump with accessories to perform adjustment by drop rate (static calibration) and dynamic calibration methods during the XXVIII Brazilian Congress of Extracorporeal Circulation. Perfusionists were asked to adjust the roller pump according to the procedure they usually do in their service. After each adjustment pressure was measured by dynamic calibration method with DAC. The research was approved by the Research Ethics Committee of UNICAMP, Nº 1144/2010. RESULTS: There were 56 perfusionists in this study. Pressure average of 56 measurements of dynamic calibration was 434 ± 214 mmHg; 76 percent of measurements were within the recommended range for the use of the dynamic calibration method (between 150 and 500 mmHg). CONCLUSION: Brazilian perfusionists tend to adjust roller pumps with less occlusive settings. The amplitudes of the dynamic calibration pressure tend to be smaller for more experienced perfusionists because their skills increase with time. The device can be used by the perfusionist to adjust roller pumps with greater accuracy and mainly repeatability in few minutes.

Late outcomes of mitral repair in rheumatic patients.

INTRODUCTION AND AIMS: The long-term results after surgical repair of rheumatic mitral valve remain controversial in literature. Our aim was to determine the predictive factors which impact the long-term results after isolated rheumatic mitral valve repair and to evaluate the effect of those factors on reoperation and late mortality. METHODS: One hundred and four patients with rheumatic valve disease who had undergone mitral valve repair with or without tricuspid valve annuloplasty were included. All patients with associated procedures were excluded. The predictive variables for reoperation were assessed with Cox regression and Kaplan Meier survival curves. RESULTS: The mean follow-up time was 63 ± 39 months (CI 95% 36 to 74 months). The functional class III and IV was observed in 65.4% of all patients. The posterior ring annuloplasty was performed in 33 cases, comissutoromy in 21 cases, and comissurotomy with posterior ring annuloplasty in 50 patients. There was no operative mortality. The late mortality was 2.8% (three patients). The late reoperation was associated with residual mitral valve regurgitation after surgery (P<0.001), pulmonary hypertension at the pre-operative time (P<0.001), age (P<0.04) and functional class at the post-operative time (P<0.001). We observed freedom from reoperation rates at 5 and 10 years of 91.2 ± 3.4% and 71.1 ± 9.2%, respectively. CONCLUSION: Repair of mitral valve in rheumatic valve disease is feasible with good long-term outcomes. Preoperative pulmonary hypertension, residual mitral valve regurgitation after surgery, age and functional class are predictors of late reoperation.

Systemic inflammation caused by chronic periodontite in patients victims of acute ischemic heart attack.

OBJECTIVE: Infectious and inflammatory processes mediated by bacteria in distant sites have been described as a risk factor for acute ischemic heart disease (AIHD). METHODS: One hundred one patients with AIHD with and without chronic periodontitis (CP) were included in this study. Patients were admitted to the HC UNICAMP and stratified into three groups: in group 1, we selected patients with severe chronic periodontitis (31 men and 19 women, mean age 55.1 +/- 11.29 years old); the group 2 with mild chronic periodontitis (40 men and 28 women, mean age 54.8 +/- 10.37 years old) and group 3 represented by the toothless (43 men and 20 women, mean age 67.5 +/- 8.55 years old). Blood samples were collected to measure the lipid profiles, hematological and blood glucose levels. In addition, biopsies of seventeen coronary arteries with atherosclerosis and an equal number of internal mammary arteries without atherosclerotic degeneration in group 1 were investigated. Statistical analysis by analysis of variance (ANOVA) and Scheffé test for multiple comparisons was performed. RESULTS: Triglyceride and LDL levels were elevated in group 1 than in group 2. HDL were reduced by 20% in group 1 and remained reduced by 8% in toothless. Blood glucose was higher in group 1. DNA of periodontal bacteria was detected in 58.8% of the coronary arteries. CONCLUSIONS: Patients with (AIHD) and severe chronic periodontitis may have altered lipid profile, as well as microorganisms associated with CP can permeate into coronary vessels.

The effects of modified ultrafiltration on pulmonary function and transfusion requirements in patients underwent coronary artery bypass graft surgery.

OBJECTIVE: The inflammatory response after cardiac surgery increases vascular permeability leading to higher mortality and morbidity in the post operative time. The modified ultrafiltration (MUF) had shown benefits on respiratory, and hemodynamic in pediatric patients. This approach in adults is not well established yet. We hypothesize that modified ultrafiltration may improve respiratory, hemodynamic and coagulation function in adults after cardiac surgeries. METHODS: A prospective randomized study was carried out with 37 patients who underwent coronary artery bypass graft surgery (CABG) were randomized either to MUF (n=20) at the end of bypass or to control (no MUF) (n=17). The anesthesia and ICU team were blinded for the group selection. The MUF were carried out for 15 minutes after the end of bypass. The patients data were taken at beginning of anesthesia, ending of bypass, ending MUF, 24 hours, and 48 hours after surgery. For clinical outcome the pulmonary, hemodynamic and coagulation function were evaluated. RESULTS: We observed lower drain loss in the MUF group compared to control group after 48 hours (598 +/- 123 ml vs. 848 +/- 455 ml; P=0.04) and required less red blood cells units transfusion compared to control group (0.6 +/- 0.6 units/patient vs.1.6 +/- 1.1 units/patient; P=0.03). The MUF group showed lower airway resistance (9.3 +/- 0.4 cmH2O.L-1s-1 vs. 12.1 +/- 0.8 cmH2O.L-1s-1; P=0.04). There were no deaths in both groups. CONCLUSION: The MUF reduces post operatory bleeding and red blood cells units transfusion, but with no differences on clinical outcome were observed. The routinely MUF employment was not associated with hemodynamic instability.