Teste de Limiar de Desfibrilação e Seguimento a Longo Prazo de Pacientes com Cardiopatia Crônica da Doença de Chagas / Defibrillation Threshold Testing and Long-term Follow-up in Chagas Disease

Resumo Fundamento A morte súbita cardíaca (MSC) é a causa mais comum de óbito na cardiomiopatia crônica da doença de Chagas (CCDC). Visto que muitos pacientes com CCDC que são candidatos a receber um cardioversor desfibrilador implantável (CDI) atendem a critérios que sugerem alto risco de apresentarem limiares de desfibrilação elevados, sugere-se realizar um teste de limite de desfibrilação (LDF). Objetivos Investigamos o uso do teste de LDF em pacientes com CCDC, com enfoque nos óbitos relacionados ao implante do CDI e na ocorrência de eventos arrítmicos e o tratamento oferecido durante o seguimento de longo prazo. Métodos Avaliações retrospectivas de 133 pacientes com CCDC que receberam CDI, principalmente para prevenção secundária. Foram coletados dados demográficos, clínicos e laboratoriais, escore de Rassi e dados do teste de LDF. Adotou-se p<0,05 como estatisticamente significativo. Resultados A média de idade foi 61±13 anos, e 72% da amostra era do sexo masculino. A fração de ejeção basal do ventrículo esquerdo foi 40±15%, e o escore de Rassi médio foi 10±4 pontos. Não ocorreram óbitos durante o teste de LDF, e não foram documentadas falhas do CDI. Foi identificada relação entre escore de Rassi basal mais elevado e LDFs mais elevados (ANOVA =0,007). O tempo médio até o primeiro choque foi de 474±628 dias, mas a aplicação de choque foi necessária em apenas 28 (35%) pacientes com TV, visto que a maioria dos casos se resolveu espontaneamente ou através da programação de ATP. Após seguimento clínico de 1728±1189 dias, em média, ocorreram 43 óbitos, relacionados principalmente a insuficiência cardíaca progressiva e sepse. Conclusões Um teste de LDF de rotina pode não ser necessário para pacientes com CCDCs que receberam CDI para prevenção secundária. LDFs elevados parecem ser incomuns e podem estar relacionados a escore de Rassi elevado.

Abstract Background Sudden cardiac death is the most common cause of death in chronic Chagas cardiomyopathy (CCC). Because most CCC patients who are candidates for implantable cardioverter-defibrillators (ICD) meet criteria for high defibrillation threshold values, a defibrillator threshold test (DTT) is suggested. Objectives We investigated the use of DTT in CCC patients, focusing on deaths related to ICD and arrhythmic events, as well as treatment during long-term follow-up. Methods We retrospectively evaluated 133 CCC patients who received an ICD mainly for secondary prevention. Demographic, clinical, laboratory data, Rassi score, and DTT data were collected, with p < 0.05 considered significant. Results The mean patient age was 61 (SD, 13) years and 72% were men. The baseline left ventricular ejection fraction was 40 (SD, 15%) and the mean Rassi score was 10 (SD, 4). No deaths occurred during DTT and no ICD failures were documented. There was a relationship between higher baseline Rassi scores and higher DTT scores (ANOVA = 0.007). The mean time to first shock was 474 (SD, 628) days, although shock was only necessary for 28 (35%) patients with ventricular tachycardia, since most cases resolved spontaneously or through antitachycardia pacing. After a mean clinical follow-up of 1728 (SD, 1189) days, 43 deaths occurred, mainly related to progressive heart failure and sepsis. Conclusions A routine DTT may not be necessary for CCC patients who receive an ICD for secondary prevention. High DTT values seem to be unusual and may be related to high Rassi scores.

Defibrillation Threshold Testing and Long-term Follow-up in Chagas Disease. / Teste de Limiar de Desfibrilação e Seguimento a Longo Prazo de Pacientes com Cardiopatia Crônica da Doença de Chagas.

BACKGROUND: Sudden cardiac death is the most common cause of death in chronic Chagas cardiomyopathy (CCC). Because most CCC patients who are candidates for implantable cardioverter-defibrillators (ICD) meet criteria for high defibrillation threshold values, a defibrillator threshold test (DTT) is suggested. OBJECTIVES: We investigated the use of DTT in CCC patients, focusing on deaths related to ICD and arrhythmic events, as well as treatment during long-term follow-up. METHODS: We retrospectively evaluated 133 CCC patients who received an ICD mainly for secondary prevention. Demographic, clinical, laboratory data, Rassi score, and DTT data were collected, with p < 0.05 considered significant. RESULTS: The mean patient age was 61 (SD, 13) years and 72% were men. The baseline left ventricular ejection fraction was 40 (SD, 15%) and the mean Rassi score was 10 (SD, 4). No deaths occurred during DTT and no ICD failures were documented. There was a relationship between higher baseline Rassi scores and higher DTT scores (ANOVA = 0.007). The mean time to first shock was 474 (SD, 628) days, although shock was only necessary for 28 (35%) patients with ventricular tachycardia, since most cases resolved spontaneously or through antitachycardia pacing. After a mean clinical follow-up of 1728 (SD, 1189) days, 43 deaths occurred, mainly related to progressive heart failure and sepsis. CONCLUSIONS: A routine DTT may not be necessary for CCC patients who receive an ICD for secondary prevention. High DTT values seem to be unusual and may be related to high Rassi scores.

FUNDAMENTO: A morte súbita cardíaca (MSC) é a causa mais comum de óbito na cardiomiopatia crônica da doença de Chagas (CCDC). Visto que muitos pacientes com CCDC que são candidatos a receber um cardioversor desfibrilador implantável (CDI) atendem a critérios que sugerem alto risco de apresentarem limiares de desfibrilação elevados, sugere-se realizar um teste de limite de desfibrilação (LDF). OBJETIVOS: Investigamos o uso do teste de LDF em pacientes com CCDC, com enfoque nos óbitos relacionados ao implante do CDI e na ocorrência de eventos arrítmicos e o tratamento oferecido durante o seguimento de longo prazo. MÉTODOS: Avaliações retrospectivas de 133 pacientes com CCDC que receberam CDI, principalmente para prevenção secundária. Foram coletados dados demográficos, clínicos e laboratoriais, escore de Rassi e dados do teste de LDF. Adotou-se p<0,05 como estatisticamente significativo. RESULTADOS: A média de idade foi 61±13 anos, e 72% da amostra era do sexo masculino. A fração de ejeção basal do ventrículo esquerdo foi 40±15%, e o escore de Rassi médio foi 10±4 pontos. Não ocorreram óbitos durante o teste de LDF, e não foram documentadas falhas do CDI. Foi identificada relação entre escore de Rassi basal mais elevado e LDFs mais elevados (ANOVA =0,007). O tempo médio até o primeiro choque foi de 474±628 dias, mas a aplicação de choque foi necessária em apenas 28 (35%) pacientes com TV, visto que a maioria dos casos se resolveu espontaneamente ou através da programação de ATP. Após seguimento clínico de 1728±1189 dias, em média, ocorreram 43 óbitos, relacionados principalmente a insuficiência cardíaca progressiva e sepse. CONCLUSÕES: Um teste de LDF de rotina pode não ser necessário para pacientes com CCDCs que receberam CDI para prevenção secundária. LDFs elevados parecem ser incomuns e podem estar relacionados a escore de Rassi elevado.

Electrical Storm in Chagas Cardiomyopathy: Clinical Predictors, Outcome, and Arrhythmic Characteristics in a Prospective Registry.

OBJECTIVES: This study of patients with Chagas heart disease (CHD) with an implantable cardioverter-defibrillator (ICD) for secondary prevention of sudden cardiac death sought to compare the characteristics of those with or without electrical storm (ES) during long-term follow-up. BACKGROUND: ES is a common problem in patients with CHD harboring an ICD, but data on clinical predictors and outcomes are limited. METHODS: The authors retrospectively evaluated 110 patients with CHD with a mean follow-up of 1,949 ± 1,271 days. Demographic, clinical, arrhythmia characteristics, ICD treatment, and death data were collected. Descriptive statistics included mean ± SD and Fisher exact tests used for comparisons. A p value <0.05 was considered significant. RESULTS: The ES group (n = 57; 43 men; age 62 ± 10 years) and the non-ES group (n = 53; 43 men; age 57 ± 14 years) had similar baseline demographic and clinical parameters, but left ventricular ejection fraction was higher in the ES group (44 ± 14% vs. 37 ± 14%; p = 0.02) and QRS duration was shorter (109 ± 35 ms vs. 134 ± 36 ms; p = 0.0027). Mortality rates were comparable in the 2 groups (odds ratio: 1.2; 95% confidence interval: 0.79 to 1.85; p = 0.44). The ES group presented 116 ES (2.03 ±1.47, 1 to 6). A total of 2,953 (61%) arrhythmic events required ICD therapy. No deaths occurred directly caused by ES, but clinical triggers were reported in 20 patients. CONCLUSIONS: ES is frequent in CHD but in itself does not carry a worse prognosis in this study population and was not associated with a more depressed left ventricular systolic function or a longer QRS.

Long-term follow-up of Chagas heart disease patients receiving an implantable cardioverter-defibrillator for secondary prevention.

BACKGROUND: Chagas heart disease (CHD) is a dilated cardiomyopathy characterized by malignant ventricular arrhythmias and increased risk of sudden cardiac death (SCD). Much controversy exists concerning the efficacy of implantable cardioverter-defibrillator (ICDs) in CHD because of mixed results observed. We report our long-term experience with ICDs for secondary prevention in CHD, with the specific aim of assessing the results in groups with preserved or depressed global left ventricular function. METHODS: 111 patients (75 males; 60 ± 12 years) were followed for 1,948 ± 1,275 days after ICD. Time to death was the primary outcome; LVEF ≤ 45% the exposure; and age, gender, and ICD therapy delivery the potential confounders. We used time-to-event methods and Cox proportional models for analysis, censoring observations at time of death or at 5-year follow-up in survivors. RESULTS: Seventy-two percent of the patients presented at least one sustained ventricular arrhythmia requiring appropriate therapy, and only three patients received inappropriate therapy. Death occurred in 50 (45%) patients, with an annual mortality rate of 8.4%, mostly due to refractory heart failure or noncardiac causes. Unadjusted survival rates were significantly distinct between patients with left ventricular ejection fraction (LVEF) ≤ 45% (26 deaths), 50.5% (95% confidence interval [CI]: 36.2%-63.2%) when compared to patients with LVEF > 45% (10 deaths), 77.6% (95% CI: 62.3%-87.3%, P < 0.01). After adjusting for confounders, low LVEF (hazard ratio [HR]: 5.2, 95% CI: 2.3-11.6), age (HR: 1.04, 95% CI: 1.01-1.07), and female gender (HR: 3.97, 95% CI: 1.85-8.54) were independently associated with the outcome. CONCLUSIONS: ICDs successfully aborted life-threatening arrhythmias in CHD patients. Impaired left ventricular function predicted higher mortality in CHD patients with an ICD for secondary prevention of SCD.

Cardiopulmonary bypass ischemic hepatitis reported in five patients

Abstract Objective: In cardiac surgery, the lung, renal and neurological events are the most frequent complications. Less common, acute liver failure is a serious complication that adds high morbidity, mortality, and costs. Therefore, this communication aimed to retrospectively evaluate five patients who presented, in 2014, severe acute liver failure in the immediate postoperative period. Methods: Retrospective data analysis of patients' medical records that showed severe liver failure has been computed in the medical records of five patients undergoing cardiac surgery at the Hospital da Faculdade de Medicina de Ribeirão Preto – USP in the immediate postoperative period from February 1, 2014 to December 12, 2014. The study selected five males patients, 60 to 67 years old, cardiopulmonary bypass mean time of 101.4 minutes (varying from 80 to 140 minutes), who presented acute perioperative liver failure. Results: The five patients showed an impressive increase of blood transaminase (serum alanine aminotransferase), suggesting acute hepatitis. The evolution of all patients was catastrophic, with severe hemodynamic effects and death. Many studies suggest that systemic hypotension is an important pathogenic factor for ischemic hepatitis. However, our data and previous studies raise the possibility that other yet unknown factors other than hypotension may be part of the pathophysiology of cardiopulmonary bypass after ischemic hepatitis (anticoagulation inadequate for the quality of heparin and protamine, etc.). Conclusion: Currently, there are no conclusive studies on the prevention of perioperative liver failure. More well-designed studies are needed on the introduction and evolution of liver dysfunction after cardiac surgery.

Methylene blue to treat protamine-induced anaphylaxis reactions. An experimental study in pigs

ABSTRACT Objective: To examine if methylene blue (MB) can counteract or prevent protamine (P) cardiovascular effects. Methods: The protocol included five heparinized pig groups: Group Sham -without any drug; Group MB - MB 3 mg/kg infusion; Group P - protamine; Group P/MB - MB after protamine; Group MB/P - MB before protamine. Nitric oxide levels were obtained by the nitric oxide/ozone chemiluminescence method, performed using the Nitric Oxide Analizer 280i (Sievers, Boulder, CO, USA). Malondialdehyde plasma levels were estimated using the thiobarbiturate technique. Results: 1) Groups Sham and MB presented unchanged parameters; 2) Group P - a) Intravenous protamine infusion caused mean arterial pressure decrease and recovery trend after 25-30 minutes, b) Cardiac output decreased and remained stable until the end of protamine injection, and c) Sustained systemic vascular resistance increased until the end of protamine injection; 3) Methylene blue infusion after protamine (Group P/MB) - a) Marked mean arterial pressure decreased after protamine, but recovery after methylene blue injection, b) Cardiac output decreased after protamine infusion, recovering after methylene blue infusion, and c) Sustained systemic vascular resistance increased after protamine infusion and methylene blue injections; 4) Methylene blue infusion before protamine (Group MB/P) - a) Mean arterial pressure decrease was less severe with rapid recovery, b) After methylene blue, there was a progressive cardiac output increase up to protamine injection, when cardiac output decreased, and c) Sustained systemic vascular resistance decreased after protamine, followed by immediate Sustained systemic vascular resistance increase; 5) Plasma nitrite/nitrate and malondialdehyde values did not differ among the experimental groups. Conclusion: Reviewing these experimental results and our clinical experience, we suggest methylene blue safely prevents and treats hemodynamic protamine complications, from the endothelium function point of view.

Twenty years of vasoplegic syndrome treatment in heart surgery. Methylene blue revised.

OBJECTIVE: This study was conducted to reassess the concepts established over the past 20 years, in particular in the last 5 years, about the use of methylene blue in the treatment of vasoplegic syndrome in cardiac surgery. METHODS: A wide literature review was carried out using the data extracted from: MEDLINE, SCOPUS and ISI WEB OF SCIENCE. RESULTS: The reassessed and reaffirmed concepts were 1) MB is safe in the recommended doses (the lethal dose is 40 mg/kg); 2) MB does not cause endothelial dysfunction; 3) The MB effect appears in cases of NO up-regulation; 4) MB is not a vasoconstrictor, by blocking the cGMP pathway it releases the cAMP pathway, facilitating the norepinephrine vasoconstrictor effect; 5) The most used dosage is 2 mg/kg as IV bolus, followed by the same continuous infusion because plasma concentrations sharply decrease in the first 40 minutes; and 6) There is a possible "window of opportunity" for MB's effectiveness. In the last five years, major challenges were: 1) Observations about side effects; 2) The need for prophylactic and therapeutic guidelines, and; 3) The need for the establishment of the MB therapeutic window in humans. CONCLUSION: MB action to treat vasoplegic syndrome is time-dependent. Therefore, the great challenge is the need, for the establishment the MB therapeutic window in humans. This would be the first step towards a systematic guideline to be followed by possible multicenter studies.

Twenty years of vasoplegic syndrome treatment in heart surgery. Methylene blue revised / Vinte anos de tratamento da síndrome vasoplégica em cirurgia cardíaca. Azul de metileno revisado

Objective: This study was conducted to reassess the concepts established over the past 20 years, in particular in the last 5 years, about the use of methylene blue in the treatment of vasoplegic syndrome in cardiac surgery. Methods: A wide literature review was carried out using the data extracted from: MEDLINE, SCOPUS and ISI WEB OF SCIENCE. Results: The reassessed and reaffirmed concepts were 1) MB is safe in the recommended doses (the lethal dose is 40 mg/kg); 2) MB does not cause endothelial dysfunction; 3) The MB effect appears in cases of NO up-regulation; 4) MB is not a vasoconstrictor, by blocking the cGMP pathway it releases the cAMP pathway, facilitating the norepinephrine vasoconstrictor effect; 5) The most used dosage is 2 mg/kg as IV bolus, followed by the same continuous infusion because plasma concentrations sharply decrease in the first 40 minutes; and 6) There is a possible "window of opportunity" for MB's effectiveness. In the last five years, major challenges were: 1) Observations about side effects; 2) The need for prophylactic and therapeutic guidelines, and; 3) The need for the establishment of the MB therapeutic window in humans. Conclusion: MB action to treat vasoplegic syndrome is time-dependent. Therefore, the great challenge is the need, for the establishment the MB therapeutic window in humans. This would be the first step towards a systematic guideline to be followed by possible multicenter studies. .

Objetivo: O presente estudo foi realizado com a finalidade de reavaliar conceitos estabelecidos em 20 anos, com ênfase nos últimos 5 anos, sobre a utilização do azul de metileno no tratamento da síndrome vasoplégica em cirurgia cardíaca. Métodos: Foram considerados dados da literatura utilizando-se três bases de dados (MEDLINE, SCOPUS e ISI Web of Science). Resultados: Os conceitos reavaliados e reafirmados foram: 1) Nas doses recomendadas o AM é seguro (a dose letal é de 40 mg/kg); 2) O AM não causa disfunção endotelial; 3) O efeito do AM só aparece em caso de supra nivelamento do NO; 4) O AM não é um vasoconstritor, pelo bloqueio da via GMPc ele libera a via do AMPc, facilitando o efeito vasoconstritor da norepinefrina; 5) A dosagem mais utilizada é de 2 mg/kg, como bolus EV, seguida de infusão contínua porque as concentrações plasmáticas decaem fortemente nos primeiros 40 minutos, e; 6) Existe uma "janela de oportunidade" precoce para efetividade do AM. Nos últimos cinco anos, os principais desafios foram: 1) Observações de efeitos colaterais; 2) A necessidade de diretrizes, e; 3) A necessidade da determinação de uma janela terapêutica para o uso do AM em humanos. Conclusão: O efeito do AM no tratamento da SV é dependente do tempo, portanto, o grande desafio atual é a necessidade do estabelecimento da janela terapêutica do AM em humanos. Esse seria o primeiro passo para a sistematização de uma diretriz a ser seguida por possíveis estudos multicêntricos. .

Retrograde autologous priming in cardiopulmonary bypass in adult patients: effects on blood transfusion and hemodilution / Perfusato autólogo retrógrado no circuito de circulação extracorpórea em pacientes adultos: efeitos sobre a hemodiluição e transfusão de sangue

INTRODUCTION: Retrograde autologous priming (RAP) is a cardiopulmonary bypass (CPB) method, at low cost. Previous studies have shown that this method reduces hemodilution and blood transfusions needs through increased intra-operative hematocrit. OBJECTIVE: To evaluate RAP method, in relation to standard CPB (crystalloid priming), in adult patients. METHODS: Sixty-two patients were randomly allocated to two groups: 1) Group RAP (n = 27) of patients operated using the RAP and; 2) Control group of patients operated using CPB standard crystalloid method (n = 35). The RAP was performed by draining crystalloid prime from the arterial and venous lines, before CPB, into a collect recycling bag. The main parameters analyzed were: 1) CPB hemodynamic data; 2) Hematocrit and hemoglobin values; 3) The need for blood transfusions. RESULTS: It was observed statistically significant fewer transfusions during surgery and reduced CPB hemodilution using RAP. The CPB hemodynamic values were similar, observing a tendency to use lower CPB flows in the RAP group patients. CONCLUSION: This investigation was designed to be a small-scale pilot study to evaluate the effects of RAP, which were demonstrated concerning the CPB hemodilution and blood transfusions.

INTRODUÇÃO: Perfusato autólogo retrógrado (PAR) é uma técnica de circulação extracorpórea (CEC) com baixos custos. Estudos anteriores demonstraram que esta técnica reduz a hemodiluição e a necessidade de transfusões de sangue por meio do aumento do hematócrito intraoperatório. OBJETIVO: Avaliar técnica de PAR em relação à CEC técnica padrão (perfusato cristaloide) em pacientes adultos. MÉTODOS: Sessenta e dois pacientes foram aleatoriamente alocados em dois grupos: 1) Grupo PAR (n = 27), constituído por pacientes operados utilizando a técnica de PAR e; 2) Grupo Controle, constituído por pacientes operados utilizando técnica padrão de CEC com cristaloides (n = 35). A PAR foi realizada drenando-se o perfusato cristaloide das linhas arterial e venosa, antes da CEC, para uma bolsa coletora de recirculação. Os principais parâmetros analisados foram: 1) parâmetros hemodinâmicos da CEC; 2) valores de hematócrito e hemoglobina; e; 3) necessidade de transfusões de sangue. RESULTADOS: Observaram-se diferenças estatisticamente significativas de transfusão no intraoperatório e diminuição da hemodiluição em CEC utilizando PAR. Os valores hemodinâmicos durante a CEC foram semelhantes, observando-se tendência de utilização de fluxos menores na CEC dos pacientes do grupo PAR. CONCLUSÃO: O presente estudo foi projetado em pequena escala para avaliar os efeitos do PAR, o que foi demonstrado em relação aos já conhecidos efeitos na diminuição da hemodiluição em CEC e transfusão sanguínea, porém não mostrou vantagens hemodinâmicas em relação à técnica padrão com perfusato cristaloide.

Retrograde autologous priming in cardiopulmonary bypass in adult patients: effects on blood transfusion and hemodilution.

INTRODUCTION: Retrograde autologous priming (RAP) is a cardiopulmonary bypass (CPB) method, at low cost. Previous studies have shown that this method reduces hemodilution and blood transfusions needs through increased intra-operative hematocrit. OBJECTIVE: To evaluate RAP method, in relation to standard CPB (crystalloid priming), in adult patients. METHODS: Sixty-two patients were randomly allocated to two groups: 1) Group RAP (n = 27) of patients operated using the RAP and; 2) Control group of patients operated using CPB standard crystalloid method (n = 35). The RAP was performed by draining crystalloid prime from the arterial and venous lines, before CPB, into a collect recycling bag. The main parameters analyzed were: 1) CPB hemodynamic data; 2) Hematocrit and hemoglobin values; 3) The need for blood transfusions. RESULTS: It was observed statistically significant fewer transfusions during surgery and reduced CPB hemodilution using RAP. The CPB hemodynamic values were similar, observing a tendency to use lower CPB flows in the RAP group patients. CONCLUSION: This investigation was designed to be a small-scale pilot study to evaluate the effects of RAP, which were demonstrated concerning the CPB hemodilution and blood transfusions.

Cabos-Eletrodos epimiocárdicos / Epimyocardial electrode leads

O implante de marcapasso com cabos-eletrodos endocavitários é a técnica preferida na atualidade. Entretanto, persiste o implante de cabo-eletrodo epiomiocárdico ou, simplesmente, epicárdico uma vez que nem todos os casos são elegíveis para o implante via endocavitária. Diferentes tipos de cabos-eletrodos estão disponíveis no mercado para implante de marcapassos epicárdicos definitivos e também temporários. Apesar de muito restrito, temos ainda o uso do cabo-eletrodo epicárdico na cardioversão-desfibrilação. Quanto à forma de fixação, eles são divididos em penetrantes e não penetrantes. Diversos acessos cirúrgicos podem ser adotados com o objetivo de expor o local no coração para realizar o implante desses cabos-eletrodos. O implante epicárdico deve ser abordado de forma individualizada para cada caso.

Fatores de risco para lesão renal aguda após cirurgia cardíaca / Risk factors for acute renal failure after heart surgery

Objetivo: Identificar fatores de risco associados à lesão renal aguda em pacientes com níveis séricos normais de creatinina sérica que foram submetidos à revascularização cirúrgica do miocárdio e/ou cirurgia valvar. Métodos: Os dados de uma coorte de 769 pacientes foram analisados utilizando análise bivariável e regressão logística binária. Resultados: Trezentos e oitenta e um pacientes foram submetidos à revascularização isolada, 339 a cirurgia valvar e 49 a ambas. Quarenta e seis por cento dos pacientes eram do sexo feminino e a idade média foi 57 ± 14 anos. Setenta e oito (10 por cento) pacientes apresentavam disfunção renal no pósoperatório, 23 por cento destes necessitaram hemodiálise. A mortalidade geral foi 10 por cento. A mortalidade para pacientes com disfunção renal pós-operatória foi de 40 por cento (versus 7 por cento, P <0,001), 29 por cento para aqueles que não precisam diálise e 67 por cento para aqueles que necessitaram de diálise (P = 0,004). Os fatores de risco independentes identificados foram: idade (P <0,000, OR: 1,056), insuficiência cardíaca congestiva (P = 0,091, OR: 2,238), DPOC (P = 0,003, OR: 4,111), endocardite (P = 0,001, OR: 12,140, infarto do miocárdio < 30 dias (P = 0,015, OR: 4,205), cirurgia valvar (P = 0,016, OR: 2,137), tempo de circulação extracorpórea > 120 minutos (P = 0,001, OR: 7,040), doença arterial periférica (P = 0,107, 2,296). Conclusão: A disfunção renal foi a disfunção orgânica pós-operatória mais frequente em pacientes submetidos à revascularização do miocárdio e/ou cirurgia valvar e idade, presença de insuficiência cardíaca, DPOC, endocardite, infarto do miocárdio < 30 dias, doença arterial periférica, cirurgia valvar e tempo de circulação extracorpórea > 120 minutos foram os fatores de risco independentemente associados à lesão renal aguda.

Objective: The aim of the present study was to identify risk factors for acute renal failure in patients with normal levels of serum creatinine who had undergone coronary artery bypass graft (CABG) surgery and/or valve surgery. Methods: Data from a cohort of 769 patients were assessed using bivariate analyses and binary logistic regression modeling. Results: Three hundred eighty one patients underwent CABG, 339 valve surgery and 49 had undergone both simultaneously. Forty six percent of the patients were female and the mean age was 57 ± 14 years (13 to 89 years). Seventy eight (10 percent) patients presented renal dysfunction postoperatively, of these 23 percent needed hemodialysis (2.4 percent of all patients). The mortality for the whole cohort was 10 percent. The overall mortality for patients experiencing postoperative renal dysfunction was 40 percent (versus 7 percent, P < 0.001), 29 percent for those who did not need dialysis and 67 percent for those who needed dialysis (P = 0.004). The independent risk factors found were: age (P < 0.000, OR: 1.056), congestive heart failure (P = 0.091, OR: 2.238), COPD (P = 0.003, OR: 4.111), endocarditis (P = 0.001, OR: 12.140), myocardial infarction < 30 days (P = 0.015, OR: 4.205), valve surgery (P = 0.016, OR: 2.137), cardiopulmonary bypass time > 120 min (P = 0.001, OR: 7.040), peripheral arterial vascular disease (P = 0.107, 2.296). Conclusion: Renal dysfunction was the most frequent postoperative organ dysfunction in patients undergone CABG and/or valve surgery and age, congestive heart failure, COPD, endocarditis, myocardial infarction < 30 days, valve surgery, cardiopulmonary bypass time >120 min, and peripheral arterial vascular disease were the risk factors independently associated with acute renal failure (ARF).

Isolated mitral and aortic valve replacement with the St. Jude Medical valve: a midterm follow-up.

BACKGROUND: In our country, the biological valvular prostheses predominate, considering the difficulties related to anticoagulation, even in young patients, in spite of the need for repeated operations due to the degeneration of the bioprostheses. OBJECTIVES: To report our consecutive series of recipients of isolated St Jude Medical mechanical valve prosthesis in the mitral (MVR) or aortic (AVR) position. METHODS: Data from patients operated between January 1995 and December 2003 were revised in order to determine patient survival and prosthesis-related events up to December 2006. RESULTS: One hundred sixty eight patients had MVR and 117 had AVR. In the MVR cohort, the mean age was 45 years, 75% were 55 years old or younger, and 65% were females. In the ARV cohort, the mean age was 45 years, 66% were 55 years old or younger and 69% were males. Operative mortality for AVR and MVR was 7% and 7.5%, respectively. Freedom from late mortality was 81.8% at 10 years for MVR and 83% for AVR (p=0.752). Freedom from valve-related death at 10 years for the MVR cohort and AVR was 85.6% and 88.7%, respectively (p=0.698). In the MVR cohort, the freedom from reoperation was 97% and 99% in the AVR cohort (p=0.335). Freedom from thromboembolic events was 82% in the MVR cohort and 98% in the AVR cohort (p=0.049). Freedom from bleeding was 71% in the MVR cohort and 86% n the AVR cohort (0.579). Freedom from endocarditis was 98% in the MVR cohort and 99% in the AVR cohort (p=0.534). CONCLUSIONS: This series of predominantly young adult patients undergoing isolated MVR and AVR with the St Jude Medical mechanical prosthesis confirms the good performance of this valve prosthesis in agreement with previous reports.

Substituição valvar isolada com próteses metálicas St. Jude Medical em posição aórtica ou mitral: seguimento de médio prazo / Sustitución valvular aislada con prótesis metálicas St. Jude Medical en posición aórtica o mitral: seguimiento de medio plazo / Isolated mitral and aortic valve replacement with the St. Jude Medical valve: a midterm follow-up

FUNDAMENTO: Em nosso meio as próteses valvares biológicas predominam, considerando-se as dificuldades relacionadas à anticoagulação, mesmo em pacientes jovens, a despeito da necessidade de repetidas operações devido à degeneração das próteses biológicas. OBJETIVO: Apresentar a evolução em médio prazo de pacientes submetidos à substituição da valva mitral ou aórtica por prótese valvar mecânica St. Jude. MÉTODOS: Foi analisada retrospectivamente a evolução dos pacientes operados entre janeiro de 1995 e dezembro de 2003 e seguidos até dezembro de 2006. RESULTADOS: Cento e sessenta e oito pacientes receberam prótese valvar mitral e 117, aórtica. A idade média de ambos os grupos foi de 45 anos. Entre os mitrais, 75 por cento tinham até 55 anos e 65 por cento eram mulheres. Entre os aórticos, 66 por cento tinham até 55 anos e 69 por cento eram homens. Considerando-se apenas mortes relacionadas às próteses valvares, a sobrevida foi de 85,6 por cento para os mitrais e de 88,7 por cento para os aórticos (p=0,698). Entre os mitrais, 97 por cento estavam livres de reoperação, e entre os aórticos 99 por cento (p=0,335). Quanto aos eventos tromboembólicos, a porcentagem de pacientes livres foi de 82 por cento entre os mitrais e de 98 por cento entre os aórticos (p=0,049), e para os eventos hemorrágicos foi de 71 por cento e 86 por cento respectivamente (0,579). Quanto à ocorrência de endocardite, 98 por cento entre os mitrais e 99 por cento entre os aórticos estavam livres ao final de 10 anos (p=0,534). CONCLUSÃO: Nossa experiência com próteses metálicas St. Jude em uma população predominantemente jovem confirma o bom desempenho desta prótese, em acordo com outras experiências publicadas.

BACKGROUND: In our country, the biological valvular prostheses predominate, considering the difficulties related to anticoagulation, even in young patients, in spite of the need for repeated operations due to the degeneration of the bioprostheses. OBJECTIVES: To report our consecutive series of recipients of isolated St Jude Medical mechanical valve prosthesis in the mitral (MVR) or aortic (AVR) position. METHODS: Data from patients operated between January 1995 and December 2003 were revised in order to determine patient survival and prosthesis-related events up to December 2006. RESULTS: One hundred sixty eight patients had MVR and 117 had AVR. In the MVR cohort, the mean age was 45 years, 75 percent were 55 years old or younger, and 65 percent were females. In the ARV cohort, the mean age was 45 years, 66 percent were 55 years old or younger and 69 percent were males. Operative mortality for AVR and MVR was 7 percent and 7.5 percent, respectively. Freedom from late mortality was 81.8 percent at 10 years for MVR and 83 percent for AVR (p=0.752). Freedom from valve-related death at 10 years for the MVR cohort and AVR was 85.6 percent and 88.7 percent, respectively (p=0.698). In the MVR cohort, the freedom from reoperation was 97 percent and 99 percent in the AVR cohort (p=0.335). Freedom from thromboembolic events was 82 percent in the MVR cohort and 98 percent in the AVR cohort (p=0.049). Freedom from bleeding was 71 percent in the MVR cohort and 86 percent n the AVR cohort (0.579). Freedom from endocarditis was 98 percent in the MVR cohort and 99 percent in the AVR cohort (p=0.534). CONCLUSIONS: This series of predominantly young adult patients undergoing isolated MVR and AVR with the St Jude Medical mechanical prosthesis confirms the good performance of this valve prosthesis in agreement with previous reports.

FUNDAMENTO: En nuestro medio, las prótesis valvulares biológicas predominan, teniendo en cuenta las dificultades relacionadas a la anticoagulación, incluso en pacientes jóvenes, pese a la necesidad de repetidas operaciones debido a la degeneración de las prótesis biológicas. OBJETIVO: Presentar la evolución en medio plazo de pacientes sometidos a la sustitución de la válvula mitral o aórtica por prótesis valvular mecánica St. Jude. MÉTODOS: Se analizó retrospectivamente la evolución de los pacientes operados entre enero de 1995 y diciembre de 2003 y seguidos hasta diciembre de 2006. RESULTADOS: Un total de 168 pacientes recibió prótesis valvular mitral y otros 117, aórtica. La edad promedio de ambos grupos fue de 45 años. Entre los mitrales, el 75 por ciento tenía hasta 55 años y el 65 por ciento era mujeres. Entre los aórticos, el 66 por ciento tenía hasta 55 años y el 69 por ciento era de varones. Teniendo en cuenta solamente las muertes relacionadas a las prótesis valvulares, la sobrevida fue del 85,6 por ciento para los mitrales y del 88,7 por ciento para los aórticos (p=0.698). Entre los mitrales, el 97 por ciento estaba libre de reoperación, y entre los aórticos el 99 por ciento (p=0,335) lo estaba. En cuanto a los eventos tromboembólicos, el porcentaje de pacientes libres fue del 82 por ciento entre los mitrales y del 98 por ciento entre los aórticos (p=0,049), y para los eventos hemorrágicos fue del 71 por ciento y el 86 por ciento respectivamente (0,579). En cuanto a la ocurrencia de endocarditis, el 98 por ciento entre los mitrales y el 99 por ciento entre los aórticos estaba libre al final de 10 años (p=0.534). CONCLUSIÓN: Nuestra experiencia con prótesis metálicas St. Jude en una población predominantemente joven confirma el buen desempeño de esta prótesis, según otras experiencias publicadas.

Blood cardioplegia with N-acetylcysteine may reduce coronary endothelial activation and myocardial oxidative stress.

OBJECTIVES: The aim of this prospective study was to compare the efficacy of intermittent antegrade blood cardioplegia with or without n-acetylcysteine (NAC) in reducing myocardial oxidative stress and coronary endothelial activation. METHODS: Twenty patients undergoing elective isolated coronary artery bypass graft surgery were randomly assigned to receive intermittent antegrade blood cardioplegia (32 degrees C-34 degrees C) with (NAC group) or without (control group) 300 mg of NAC. For these 2 groups we compared clinical outcome, hemodynamic evolution, systemic plasmatic levels of troponin I, and plasma concentrations of malondialdehyde (MDA) and soluble vascular adhesion molecule 1 (sVCAM-1) from coronary sinus blood samples. RESULTS: Patient demographic characteristics and operative and postoperative data findings in both groups were similar. There was no hospital mortality. Comparing the plasma levels of MDA 10 min after the aortic cross-clamping and of sVCAM-1 30 min after the aortic cross-clamping period with the levels obtained before the aortic clamping period, we observed increases of both markers, but the increase was significant only in the control group (P= .039 and P= .064 for MDA; P= .004 and P= .064 for sVCAM-1). In both groups there was a significant increase of the systemic serum levels of troponin I compared with the levels observed before cardiopulmonary bypass (P< .001), but the differences between the groups were not significant (P= .570). CONCLUSIONS: Our investigation showed that NAC as an additive to blood cardioplegia in patients undergoing on-pump coronary artery bypass graft surgery may reduce oxidative stress and the resultant coronary endothelial activation.

Risk factors for acute renal failure after heart surgery.

OBJECTIVE: The aim of the present study was to identify risk factors for acute renal failure in patients with normal levels of serum creatinine who had undergone coronary artery bypass graft (CABG) surgery and/or valve surgery. METHODS: Data from a cohort of 769 patients were assessed using bivariate analyses and binary logistic regression modeling. RESULTS: Three hundred eighty one patients underwent CABG, 339 valve surgery and 49 had undergone both simultaneously. Forty six percent of the patients were female and the mean age was 57 +/- 14 years (13 to 89 years). Seventy eight (10%) patients presented renal dysfunction postoperatively, of these 23% needed hemodialysis (2.4% of all patients). The mortality for the whole cohort was 10%. The overall mortality for patients experiencing postoperative renal dysfunction was 40% (versus 7%, P < 0.001), 29% for those who did not need dialysis and 67% for those who needed dialysis (P = 0.004). The independent risk factors found were: age (P < 0.000, OR: 1.056), congestive heart failure (P = 0.091, OR: 2.238), COPD (P = 0.003, OR: 4.111), endocarditis (P = 0.001, OR: 12.140), myocardial infarction < 30 days (P = 0.015, OR: 4.205), valve surgery (P = 0.016, OR: 2.137), cardiopulmonary bypass time > 120 min (P = 0.001, OR: 7.040), peripheral arterial vascular disease (P = 0.107, 2.296). CONCLUSION: Renal dysfunction was the most frequent postoperative organ dysfunction in patients undergone CABG and/or valve surgery and age, congestive heart failure, COPD, endocarditis, myocardial infarction < 30 days, valve surgery, cardiopulmonary bypass time >120 min, and peripheral arterial vascular disease were the risk factors independently associated with acute renal failure (ARF).

Fatores de risco em septuagenários ou mais idosos submetidos à revascularização do miocárdio e ou operações valvares / Risk factors in septuagenarians or elderly patients undergone coronary artery bypass grafting and or valves operations

OBJETIVO: Pacientes septuagenários ou mais idosos necessitando de cirurgia cardíaca vêm crescendo em todo mundo. O objetivo do estudo é conhecer melhor esse grupo de pacientes e determinar fatores de risco para morbidade operatória. MÉTODOS: Revisamos 783 pacientes submetidos a operações cardíacas valvares e de revascularização do miocárdio isoladas ou associadas no período de 2002 a 2007. Tais pacientes foram divididos em "grupo <70 anos de idade" e "grupo >70 anos de idade". RESULTADOS: Cento e noventa e sete pacientes tinham 70 anos ou mais de idade (idade média 74,1 ± 3,9) e 61 por cento eram do sexo masculino. No grupo > 70 anos, foi significativamente maior o número de pacientes portadores de doença vascular periférica (9 por cento versus 5 por cento, P= 0,019), doença carotídea (5 por cento versus 2 por cento, P= 0,026) e angina instável (17 por cento versus 9 por cento, P= 0,018). Em ambos os grupos, a revascularização do miocárdio foi mais freqüente. No grupo > 70 anos, 41 por cento dos pacientes tiveram ao menos um efeito adverso, versus 22 por cento do grupo <70 anos (P<0,001). Aincidência de sangramento pós-operatório, complicações pulmonares, mediastinite, necessidade de vasopressores, disfunção renal e acidente vascular cerebral foi significativamente maior no grupo > 70 anos. A mortalidade foi maior no grupo > 70 anos (19 por cento versus 8,5 por cento, P<0,001). A regressão logística revelou que DPOC (OR: 8,6), FE (OR: 7,1), operação não eletiva (OR: 17,2) e tempo de circulação extracorpórea > 120 min (OR: 3,4) são preditores de mortalidade hospitalar no grupo estudado. CONCLUSÕES: A mortalidade hospitalar em septuagenários ou mais idosos nas operações de revascularização miocárdica e valvares isoladas ou associadas é maior que nos pacientes mais jovens.

OBJECTIVES: Septuagenarians or older patients needing heart surgery has increased in whole world. The objective of study is to know the characteristics of this group of patients and determine the risk factors for operative morbidity. METHODS: We revised the medical records of 783 patients undergone heart valve surgery, myocardial revascularization or both between 2002 and 2007. The patients were divided in "control group" (<70 years) "septuagenarian group" (70 years old or more). RESULTS: One hundred ninety seven patients were at least 70 years old (mean age 74.1±3.9) and 61 percent were male. In the control group the mean age was 52.1±11.7 and 54 percent were male. In the septuagenarians group it was significantly higher the proportion of patients suffering from peripheral vascular disease (9 percent versus 5 percent, P=0.019), carotid artery obstruction (5 percent versus 2 percent, P=0.026), unstable angina (17 percent versus 9 percent, P=0.018). In both groups coronary artery bypass surgery prevailed. In the septuagenarian group 41 percent of the patients had a least one morbid event, versus 22 percent of the patients in the control group (P<0.001). Postoperative bleeding, pulmonary complications, mediastinitis, need of vasopressors, renal dysfunction and strokes were significantly higher in the septuagenarian group. The mortality was higher in the septuagenarian (19 percent versus 8.5 percent, P<0.001). The logistic regression revealed that COPD (OR: 8.6), EF < 35 percent (OR: 7,1), non-elective operation (OR: 17,2) and cardiopulmonary bypass time >120 min (OR: 3,4) were predictive of hospital mortality in septuagenarian or older patients. CONCLUSIONS: The hospital mortality of septuagenarians or elderly is significantly higher than younger patients.

Risk factors in septuagenarians or elderly patients undergone coronary artery bypass grafting and or valves operations.

OBJECTIVES: Septuagenarians or older patients needing heart surgery has increased in whole world. The objective of study is to know the characteristics of this group of patients and determine the risk factors for operative morbidity. METHODS: We revised the medical records of 783 patients undergone heart valve surgery, myocardial revascularization or both between 2002 and 2007. The patients were divided in 'control group' (<70 years) 'septuagenarian group' (70 years old or more). RESULTS: One hundred ninety seven patients were at least 70 years old (mean age 74.1+/-3.9) and 61% were male. In the control group the mean age was 52.1+/-11.7 and 54% were male. In the septuagenarians group it was significantly higher the proportion of patients suffering from peripheral vascular disease (9% versus 5%, P=0.019), carotid artery obstruction (5% versus 2%, P=0.026), unstable angina (17% versus 9%, P=0.018). In both groups coronary artery bypass surgery prevailed. In the septuagenarian group 41% of the patients had a least one morbid event, versus 22% of the patients in the control group (P<0.001). Postoperative bleeding, pulmonary complications, mediastinitis, need of vasopressors, renal dysfunction and strokes were significantly higher in the septuagenarian group. The mortality was higher in the septuagenarian (19% versus 8.5%, P<0.001). The logistic regression revealed that COPD (OR: 8.6), EF < 35% (OR: 7,1), non-elective operation (OR: 17,2) and cardiopulmonary bypass time >120 min (OR: 3,4) were predictive of hospital mortality in septuagenarian or older patients. CONCLUSIONS: The hospital mortality of septuagenarians or elderly is significantly higher than younger patients.

Um modelo experimental de ablação do Sistema Nervoso Intrínseco Cardíaco reduz a contratilidade do coração de ratos / A new experimental model of chemical ablation of the Intrinsic Cardiac Nervous System reduces heart contractility and causes a type of dilated cardiopathy in rats

OBJETIVO: A função do Sistema Nervoso Intrínseco Cardíaco e o seu papel na doença cardíaca permanecem pobremente compreendidos. Sabe-se que o cloreto de benzalcônio (CB) induz a desnervação intrínseca do tubo digestivo. O objetivo deste estudo foi tentar produzir um modelo experimental de desnervação intrínseca do coração utilizando o CB. MÉTODO: Trinta ratos Wistar foram submetidos à aplicação intrapericárdica de CB (0,3 por cento) e trinta animais controle receberam a solução salina. Após 15 dias, os animais foram divididos em três grupos, com 10 animais tratados e 10 controles em cada. Os animais do grupo I foram submetidos a estudo radiológico e histopatológico. A área cardíaca e o índice cardiotorácico (ICT) foram medidos nas radiografias. Os animais do grupo II foram submetidos a estudo hemodinâmico com registro da pressão arterial, freqüência cardíaca e débito cardíaco. No grupo III, a integridade da inervação parassimpática extrínseca do coração foi avaliada por estimulação vagal direita. O sistema de condução foi avaliado pelo ECG basal. RESULTADOS: A aplicação de CB acarretou aumento do ICT, da área cardíaca, pressão arterial e débito cardíaco, bem como do peso ponderal e do fígado. Nestes animais, a análise histopatológica mostrou redução do número de neurônios atriais e congestão passiva crônica do fígado. A estimulação vagal não mostrou diferenças entre os grupos experimentais. CONCLUSAO: A ablação do sistema nervoso intrínseco propiciou o aparecimento de cardiopatia dilatada com insuficiência cardíaca direita e esquerda. Esse modelo experimental inédito deverá nortear futuros estudos na tentativa da elucidação da relação entre lesão neuronal e miocardiopatia.