Predictors of Appropriate Therapies and Death in Patients with Implantable Cardioverter-Defibrillator and Chronic Chagas Heart Disease. / Preditores de Terapias Apropriadas e Óbito em Pacientes com Cardiodesfibrilador Implantável e Cardiopatia Chagásica Crônica.

BACKGROUND: There are few retrospective and prospective studies on implantable cardioverter-defibrillators (ICD) in primary and secondary prevention of sudden death in chronic Chagas heart disease (CCHD). OBJECTIVES: To describe the long-term evolution of patients with CCHD and ICD and to identify and analyze predictors of mortality and appropriate device therapy in this population. METHODS: This was a historical prospective study with 117 patients with ICD and CCHD. Devices were implanted from January 2003 to December 2021. Predictors of appropriate therapies and long-term mortality were identified and analyzed. The level of statistical significance was p < 0.05. RESULTS: Patients (n = 117) had a median follow-up of 61 months (25 to 121 months); they were predominantly male (74%), with a median age of 55 years (48 to 64 years). There were 43.6% appropriate shocks, 26.5% antitachycardia pacing (ATP), and 51% appropriate therapies. During follow-up, 46 patients (39.7%) died. Mortality was 6.2% person-years (95% confidence interval [CI]: 4.6 to 8.3), with 2 sudden deaths during follow-up. Secondary prevention (hazard ratio [HR] 2.1; 95% CI: 1.1 to 4.3; p = 0.029) and ejection fraction less than 30% (HR 1.8; 95% CI: 1.1 to 3.1; p < 0.05) were predictors of appropriate therapies. Intermediate Rassi score showed a strong association with the occurrence of ATP alone (p = 0.015). Functional class IV (p = 0.007), left ventricular ejection fraction < 30 (p = 0.010), and age above 75 years (p = 0.042) were predictors of total mortality. CONCLUSION: ICDs in CCHD showed a high incidence of appropriate activation, especially in patients with secondary prevention, low left ventricular ejection fraction, and intermediate Rassi score. Patients with congestive heart failure, elevated functional class, and age over 75 years showed elevated mortality. Survival function of patients with implantable cardioverter-defibrillators and chronic Chagas heart disease. A - According to New York Heart Association functional class; B - According to left ventricular ejection fraction; C - According to Rassi score. D - According to age. CCHD: chronic Chagas heart disease; HR: hazard ratio; ICD: implantable cardioverter-defibrillator.

Preditores de Terapias Apropriadas e Óbito em Pacientes com Cardiodesfibrilador Implantável e Cardiopatia Chagásica Crônica / Predictors of Appropriate Therapies and Death in Patients with Implantable Cardioverter-Defibrillator and Chronic Chagas Heart Disease

Resumo Fundamento: Existem poucos estudos retrospectivos e prospectivos sobre cardiodesfibrilador implantável (CDI) na prevenção primária e secundária de morte súbita na cardiopatia chagásica crônica (CCC). Objetivos: Descrever a evolução a longo prazo dos portadores de CCC com CDI e identificar e analisar os preditores de mortalidade e de terapia apropriada do dispositivo nessa população. Métodos: Trata-se de um estudo prospectivo histórico com 117 pacientes portadores de CDI e CCC. Dispositivos foram implantados de janeiro de 2003 a dezembro de 2021. Fatores preditores de terapias apropriadas e mortalidade a longo prazo foram identificados e analisados. O nível de significância estatística é de p < 0,05. Resultados: Pacientes (n = 117) tiveram mediana de seguimento de 61 meses (25 a 121 meses), sendo o gênero masculino (74%) predominante e a mediana de idade de 55 anos (48 a 64 anos). Houve 43,6% de choques apropriados, 26,5% de estimulação cardíaca antitaquicardia (ATP) e 51% de terapias apropriadas. Durante o seguimento, 46 pacientes (39,7%) foram a óbito. A mortalidade foi de 6,2% pessoas-ano (intervalo de confiança [IC] 95%: 4,6 a 8,3), com 2 mortes súbitas durante o seguimento. A prevenção secundária (hazard ratio [HR] 2.1; IC 95%: 1,1 a 4,3; p = 0,029) e a fração de ejeção menor que 30% (HR 1.8; IC 95%: 1,1 a 3,1; p < 0,05) foram preditores de terapias apropriadas. Escore de Rassi intermediário apresentou uma forte associação com ocorrência de ATP isoladamente (p = 0,015). A classe funcional IV (p = 0,007), fração de ejeção do ventrículo esquerdo < 30 (p = 0,010) e a idade maior que 75 anos (p = 0,042) foram preditores de mortalidade total. Conclusão: Os desfibriladores na CCC apresentaram elevada incidência de acionamento apropriado especialmente naqueles pacientes de prevenção secundária, fração de ejeção do ventrículo esquerdo baixa e escore de Rassi intermediário. Os pacientes com insuficiência cardíaca congestiva, classe funcional avançada e idade maior que 75 anos apresentaram elevada mortalidade.

Abstract Background: There are few retrospective and prospective studies on implantable cardioverter-defibrillators (ICD) in primary and secondary prevention of sudden death in chronic Chagas heart disease (CCHD). Objectives: To describe the long-term evolution of patients with CCHD and ICD and to identify and analyze predictors of mortality and appropriate device therapy in this population. Methods: This was a historical prospective study with 117 patients with ICD and CCHD. Devices were implanted from January 2003 to December 2021. Predictors of appropriate therapies and long-term mortality were identified and analyzed. The level of statistical significance was p < 0.05. Results: Patients (n = 117) had a median follow-up of 61 months (25 to 121 months); they were predominantly male (74%), with a median age of 55 years (48 to 64 years). There were 43.6% appropriate shocks, 26.5% antitachycardia pacing (ATP), and 51% appropriate therapies. During follow-up, 46 patients (39.7%) died. Mortality was 6.2% person-years (95% confidence interval [CI]: 4.6 to 8.3), with 2 sudden deaths during follow-up. Secondary prevention (hazard ratio [HR] 2.1; 95% CI: 1.1 to 4.3; p = 0.029) and ejection fraction less than 30% (HR 1.8; 95% CI: 1.1 to 3.1; p < 0.05) were predictors of appropriate therapies. Intermediate Rassi score showed a strong association with the occurrence of ATP alone (p = 0.015). Functional class IV (p = 0.007), left ventricular ejection fraction < 30 (p = 0.010), and age above 75 years (p = 0.042) were predictors of total mortality. Conclusion: ICDs in CCHD showed a high incidence of appropriate activation, especially in patients with secondary prevention, low left ventricular ejection fraction, and intermediate Rassi score. Patients with congestive heart failure, elevated functional class, and age over 75 years showed elevated mortality.

Remote monitoring of pacemakers and defibrillators: Effective and safe in Brazil?

Background: The remote monitoring (RM) of cardiac implantable electronic devices (CIEDs) has become a common method of in-home monitoring and follow-up in high-income countries given its effectiveness, safety, convenience, and the possibility of early intervention. However, in Brazil, RM is still underutilized. Objectives: This observational study aims to demonstrate our experience of using RM in Brazil and the predictive factors of RM of CIED follow-up in Brazil. Methods: This was a prospective cohort study of patients with a CIED. Event rates are reported and clinical responses to those findings and outcomes based on the detection of RM. A logistic regression model was performed to identify predictors of more events, with P < .05 for statistical significance. Results: This study evaluated consecutive 119 patients: 30.2% with pacemakers, 42.8% with implantable cardioverter-defibrillator, 22.7% with cardiac resynchronization therapy (CRT) with defibrillator, and 3.3% with CRT with pacemaker. Events were detected in 63.9% of the cases in 29.5 ± 23 months of follow-up. The outcomes found were that 44.5% needed elective evaluation in medical treatment and 23.5% needed immediate evaluation in therapy. Logistic regression analysis showed that the groups with CRT or CRT with defibrillator (75.0%), reduced ejection fraction (76.5%), and New York Heart Association functional class ≥II (75.0%) had the highest RM event rates. Conclusions: RM proved to be effective and safe in the follow-up of patients with CIEDs in Brazil, allowing early interventions and facilitating therapeutic management.

Syncope in Patients with Cardiac Pacemakers.

INTRODUCTION: It is challenging to diagnose syncope in patients with pacemakers. Because these patients have increased morbidity and mortality risks, they require immediate attention to determine the causes in order to provide appropriate treatment. This study aimed to investigate the causes and predictive factors of syncope as well as the methods used to diagnose syncope in cardiac pacemaker patients. METHODS: Patients with pacemakers implanted owing to sinus node disease or atrioventricular block were evaluated with standardized questionnaires, endocavitary electrograms, and other tests based on the suspected causes of syncope. Mann- Whitney U tests were used to analyze continuous variables and Chi-squared or Fisher's exact tests were used for categorical variables. Logistic regression was used for multivariate analyses. Statistical significance was P<0.05. RESULTS: The study included 95 patients with pacemakers: 47 experienced syncope in the last 12 months and 48 did not. Of the 100 documented episodes of syncope, 48.9% were vasovagal syncopes, 17% had cardiac-related causes, 10.6% had unknown causes, and 8.5% had pacemaker failure. The multivariate analysis showed that a New York Heart Association (NYHA) Functional Class II was a significant factor for developing syncope (P<0.01). CONCLUSION: While the most common type of syncope in pacemaker patients was neurally mediated, it is important to perform detailed evaluations in this population as the causes of syncope can be life-threatening. The best diagnostic methods were stored electrogram analysis and the tilt table test. NYHA Functional Class II patients were found to have a higher risk for syncope.

Syncope in patients with cardiac pacemakers

Abstract Introduction: It is challenging to diagnose syncope in patients with pacemakers. Because these patients have increased morbidity and mortality risks, they require immediate attention to determine the causes in order to provide appropriate treatment. This study aimed to investigate the causes and predictive factors of syncope as well as the methods used to diagnose syncope in cardiac pacemaker patients. Methods: Patients with pacemakers implanted owing to sinus node disease or atrioventricular block were evaluated with standardized questionnaires, endocavitary electrograms, and other tests based on the suspected causes of syncope. Mann-Whitney U tests were used to analyze continuous variables and Chi-squared or Fisher's exact tests were used for categorical variables. Logistic regression was used for multivariate analyses. Statistical significance was P<0.05. Results: The study included 95 patients with pacemakers: 47 experienced syncope in the last 12 months and 48 did not. Of the 100 documented episodes of syncope, 48.9% were vasovagal syncopes, 17% had cardiac-related causes, 10.6% had unknown causes, and 8.5% had pacemaker failure. The multivariate analysis showed that a New York Heart Association (NYHA) Functional Class II was a significant factor for developing syncope (P<0.01). Conclusion: While the most common type of syncope in pacemaker patients was neurally mediated, it is important to perform detailed evaluations in this population as the causes of syncope can be life-threatening. The best diagnostic methods were stored electrogram analysis and the tilt table test. NYHA Functional Class II patients were found to have a higher risk for syncope.

Recuperação da função ventricular após ressincronização cardíaca em criança com cardiomiopatia induzida pelo marcapasso / Ventricular function recovery after cardiac resynchronization in child with pacing-induced cardiomyopathy

A cardiomiopatia induzida pelo marcapasso é uma cardiomiopatia que ocorre em pacientes expostos a estimulação ventricular direita, sendo definida pela piora da função sistólica do ventrículo esquerdo na ausência de outras etiologias possíveis, com ou sem evidência de insuficiência cardíaca. Sua incidência varia de 9% a 26%, dependendo da população estudada e do período de acompanhamento. Relata-se o caso de uma criança submetida a implante de marcapasso ventricular por bloqueio atrioventricular total, que evoluiu com disfunção ventricular grave e insuficiência cardíaca 14 meses após o implante. Após realização de terapia de ressincronização cardíaca, a criança evoluiu com melhora clínica e remodelamento reverso do ventrículo esquerdo

Pacing-induced cardiomyopathy is observed in patients exposed to right ventricular pacing and is defined as worsening of left ventricular systolic function in the absence of alternative causes, with or without clinical evidence of heart failure. Incidence ranges from 9% to 26%, depending on the study population and the length of follow-up. This is a case report of a child with univentricular pacemaker for total atrioventricular block that evolved into severe ventricular dysfunction and heart failure after implant. Cardiac resynchronization was performed and the child evolved with clinical improvement and reverse left ventricular remodeling

Quem São os Super-Respondedores à Terapia de Ressincronização Cardíaca? / Who Are the Super-Responders to Cardiac Resynchronization Therapy?

Fundamento: Pacientes submetidos à ressincronização cardíaca podem evoluir com padrões de resposta acima do esperado, com normalização dos parâmetros clínicos e ecocardiográficos. Objetivo: Analisar as características clínicas e ecocardiográficas desta população de super-respondedores, comparando-as com os demais pacientes submetidos à terapia de ressincronização cardíaca. Métodos: Estudo de coorte observacional, prospectivo, envolvendo 146 pacientes, consecutivamente submetidos a implantes de ressincronizador cardíaco. Para comparação das variáveis, foram realizados o teste exato de Fisher e o teste de Mann-Whitney. Foram considerados super-respondedores os pacientes com fração de ejeção > 50 % e classe funcional I/II (New York Heart Association) após 6 meses da terapia de ressincronização cardíaca. Resultados: A idade média foi de 64,8 ± 11,1 anos, sendo 69,8% do sexo masculino, com mediana da fração de ejeção de 29%, sendo 71,5% com bloqueio de ramo esquerdo, 12% com bloqueio de ramo direito associado a bloqueios divisionais; 16,3% com marca-passo cardíaco definitivo, 29,3% com miocardiopatia isquêmica, 59,4% com miocardiopatia dilatada e 11,2% com miocardiopatia chagásica. Foram observados 24 (16,4%) superrespondedores, sendo que 13 (8,9%) apresentaram normalização da fração de ejeção, dos diâmetros diastólicos do ventrículo esquerdo e da classe funcional. Quando comparados com os pacientes não super-respondedores, em relação às características pré-implante, os super-respondedores apresentaram-se mais no sexo feminino (58,3% vs. 22,8%; p = 0,002), maior índice de massa corporal (26,8 vs. 25,5; p = 0,013), maior fração de ejeção basal (31,0 vs. 26,9; p = 0,0003) e menores diâmetros diastólicos do ventrículo esquerdo (65,9 mm vs. 72,6 mm; p = 0,0032). Dez pacientes (41,6% dos super-respondedores) com bloqueio de ramo direito e bloqueio divisional evoluíram como super-respondedores, entretanto apenas um paciente com doença de Chagas e apenas na primeira avaliação. Conclusões: Os super-respondedores apresentaram cardiopatia de base menos avançada e sem diferenças em relação ao tipo de distúrbio de condução basal. Pacientes com bloqueio de ramo direito e bloqueio divisional, mas sem cardiopatia chagásica podem também evoluir como super-respondedores

Background: Patients submitted to cardiac resynchronization may develop response patterns that are higher than expected, with normalization of clinical and echocardiographic parameters. Objective: To analyze the clinical and echocardiographic characteristics of this population of super-responders, comparing them with the other patients submitted to cardiac resynchronization therapy. Methods: A prospective, observational cohort study involving 146 patients consecutively submitted to cardiac resynchronization implants. Fisher's exact test and Mann-Whitney test were performed to compare the variables. Patients with ejection fraction > 50% and functional class I/II (New York Heart Association) were considered super-responders after 6 months of cardiac resynchronization therapy. Results: Mean age was 64.8 ± 11.1 years, with 69.8% of males, with a median ejection fraction of 29%, 71.5% with left bundle-branch block, 12% with right bundle-branch block associated with hemiblocks; 16.3% wearing a definitive cardiac pacemaker, 29.3% with ischemic cardiomyopathy, 59.4% with dilated cardiomyopathy, and 11.2% with Chagasic cardiomyopathy. Twenty-four (16.4%) super-responders were observed, and 13 (8.9%) showed normalization of the ejection fraction, left ventricular diastolic diameters and functional class. When compared to the non-super-responder patients, in relation to the pre-implantation characteristics, the super-responders were more often females (58.3% vs. 22.8%, p = .002), had higher body mass index (26.8 vs. 25.5, p = 0.013), higher baseline ejection fraction (31.0 vs. 26.9, p = 0.0003), and lower left ventricular diastolic diameters (65.9 mm vs. 72.6 mm, p = 0.0032). Ten patients (41.6% of super-responders) with right bundle-branch block and hemiblock progressed to super-responders, although there was only one patient with Chagas' disease among them, and only at the first assessment. Conclusions: Super-responders had less advanced heart disease at baseline and no differences regarding the type of conduction disorder at baseline. Patients with right bundle-branch block and hemiblock, but without Chagasic heart disease may also progress as super-responders

Clinical Course After Cardioverter-Defibrillator Implantation: Chagasic Versus Ischemic Patients / Evolução Clínica Pós-Implante de Desfibrilador Cardíaco: Pacientes Chagásicos Versus Isquêmicos

Abstract Background: The outcome of Chagas disease patients after receiving implantable cardioverter defibrillator (ICD) is still controversial. Objective: To compare clinical outcomes after ICD implantation in patients with chronic Chagas cardiomyopathy (CCC) and ischemic heart disease (IHD). Methods: Prospective study of a population of 153 patients receiving ICD (65 with CCC and 88 with IHD). The devices were implanted between 2003 and 2011. Survival rates and event-free survival were compared. Results: The groups were similar regarding sex, functional class and ejection fraction. Ischemic patients were, on average, 10 years older than CCC patients (p < 0.05). Patients with CCC had lower schooling and monthly income than IHD patients (p < 0.05). The number of appropriate therapies was 2.07 higher in CCC patients, who had a greater incidence of appropriate shock (p < 0.05). Annual mortality rate and electrical storm incidence were similar in both groups. There was no sudden death in CCC patients, and only one in IHD patients. Neither survival time (p = 0.720) nor event-free survival (p = 0.143) significantly differed between the groups. Conclusion: CCC doubles the risk of receiving appropriate therapies as compared to IHD, showing the greater complexity of arrhythmias in Chagas patients.

Resumo Fundamento: A evolução do paciente chagásico após implante de cardiodesfibrilador implantável (CDI) é tema ainda controverso. Objetivo: Comparar a evolução clínica pós-implante do CDI em pacientes com cardiopatia chagásica crônica (CCC) e cardiopatia isquêmica (CI). Métodos: Trata-se de um estudo prospectivo histórico de uma população de 153 pacientes portadores de CDI, sendo 65 com CCC e 88 com CI. Os dispositivos foram implantados entre janeiro de 2003 e novembro de 2011, tendo-se comparado a taxa de sobrevida e a sobrevida livre de eventos entre essas populações. Resultados: Os grupos foram similares na predominância do sexo masculino, classe funcional e fração de ejeção. Os pacientes isquêmicos são em média 10 anos mais velhos que os chagásicos (p < 0,05). Os pacientes chagásicos apresentavam escolaridade e renda mensal mais baixa do que os isquêmicos (p < 0,05). Foi demonstrado que o número de terapias apropriadas nos pacientes com CCC é 2,07 vezes maior do que naqueles com CI. A incidência de choque apropriado é maior na CCC (p < 0,05). As taxas de mortalidade anual nos dois grupos foram similares, assim como a incidência de tempestade elétrica. Não houve nenhuma morte súbita nos pacientes com CCC e apenas uma nos pacientes com CI. Não houve diferença estatisticamente significativa no tempo de sobrevida entre os dois grupos (p = 0,720) nem na sobrevida livre de eventos (p = 0,143). Conclusão: A CCC duplica o risco de receber terapias apropriadas em relação à CI, mostrando assim maior complexidade das arritmias nos pacientes chagásicos.

Clinical Course After Cardioverter-Defibrillator Implantation: Chagasic Versus Ischemic Patients.

BACKGROUND: The outcome of Chagas disease patients after receiving implantable cardioverter defibrillator (ICD) is still controversial. OBJECTIVE: To compare clinical outcomes after ICD implantation in patients with chronic Chagas cardiomyopathy (CCC) and ischemic heart disease (IHD). METHODS: Prospective study of a population of 153 patients receiving ICD (65 with CCC and 88 with IHD). The devices were implanted between 2003 and 2011. Survival rates and event-free survival were compared. RESULTS: The groups were similar regarding sex, functional class and ejection fraction. Ischemic patients were, on average, 10 years older than CCC patients (p < 0.05). Patients with CCC had lower schooling and monthly income than IHD patients (p < 0.05). The number of appropriate therapies was 2.07 higher in CCC patients, who had a greater incidence of appropriate shock (p < 0.05). Annual mortality rate and electrical storm incidence were similar in both groups. There was no sudden death in CCC patients, and only one in IHD patients. Neither survival time (p = 0.720) nor event-free survival (p = 0.143) significantly differed between the groups. CONCLUSION: CCC doubles the risk of receiving appropriate therapies as compared to IHD, showing the greater complexity of arrhythmias in Chagas patients.

Preditores de mortalidade em pacientes com cardiopatia isquêmica e cardiopatia chagásica crônica com cardiodesfibrilador implantável / Predictors of mortality in ischemic heart disease and Chagas disease patients with implantable cardioverter-defibrillator

Introdução: A cardiopatia chagásica crônica e a cardiopatia isquêmica são duas das principais causas de insuficiência cardíaca crônica na América Latina e também são relacionadas a morte súbita cardíaca, sendo, portanto, indicações comuns para o uso de cardiodesfibriladores implantáveis. Este estudo teve como objetivo avaliar preditores de mortalidade em pacientes com cardiopatia chagásica crônica e cardiopatia isquêmica com cardiodesfibrilador implantável. Método: Estudo prospectivo histórico que incluiu 153 pacientes (65 portadores de cardiopatia chagásica crônica e 88 portadores de cardiopatia isquêmica), acompanhados entre 2003 e 2011 no Hospital Universitário Walter Cantídio por um tempo médio de 32 (14,7-55) meses. Foram realizadas análises de degressão de Cox uni e multivariada além de teste de proporcionalidade de Schoenfeld e dos resíduos Cox-Snell. Resultados: Os grupos foram similares quanto a sexo, classe funcional e fração de ejeção. Quando analisados em conjunto, idade > 60 anos e classe funcional IV foram fatores de maior mortalidade. No grupo com cardiopatia chagásica crônica, baixa escolaridade e fração de ejeção < 30% aumentaram a chance de morte; já no grupo com cardiopatia isquêmica, apenas a idade aumentou a chance de morte. Os pacientes chagásicos apresentaram escolaridade e renda mensal inferiores, comparativamente aos isquêmicos. Conclusão: Idade > 60 anos e classe funcional IV foram preditores de pior evolução no subgrupo de pacientes portadores de cardiodesfibrilador implantável com cardiopatia chagásica crônica e cardiopatia isquêmica.

Background: Chronic Chagas disease and ischemic heart disease are two of the main causes of chronic heart failure in Latin America and are also related to sudden cardiac death and have, therefore, common indications for the use of implantable cardioverter-defibrillators. The objective of this study was to measure mortality predictors in patients with Chagas disease and ischemic heart disease with an implantable cardioverter-defibrillator. Method: A prospective study including 153 patients, 65 with Chagas disease and 88 with ischemic heart disease, between 2003-2011 at Hospital Universitário Walter Cantídio. The follow-up was a median of 32 (14.7 to 55) months. Cox regression univariate and multivariate analyzes were performed in addition to Schoenfeld and Cox-Snell residuals to test proportional hazards. Results: The groups were similar for gender, functional class and ejection fraction. When analyzed in combination, age > 60 years and functional class IV were predictors for higher mortality. In the group with chronic Chagas disease, low education levels and ejection fraction < 30% increase in the probability of death; whereas in the group with ischemic heart disease, only age increased the probability of death. Chagasic patients had lower educational levels and monthly incomes when compared to ischemic patients. Conclusion: Age > 60 years and functional class IV were predictors of poor outcomes in the subgroup of patients with implantable cardioverter-defibrillator with chronic Chagas disease and ischemic heart disease.

Echocardiographic Predictors of Worse Outcome After Cardiac Resynchronization Therapy / Parâmetros Ecocardiográficos Preditores de Pior Evolução após a Terapia de Ressincronização Cardíaca

Abstract Background: Cardiac resynchronization therapy (CRT) is the recommended treatment by leading global guidelines. However, 30%-40% of selected patients are non-responders. Objective: To develop an echocardiographic model to predict cardiac death or transplantation (Tx) 1 year after CRT. Method: Observational, prospective study, with the inclusion of 116 patients, aged 64.89 ± 11.18 years, 69.8% male, 68,1% in NYHA FC III and 31,9% in FC IV, 71.55% with left bundle-branch block, and median ejection fraction (EF) of 29%. Evaluations were made in the pre‑implantation period and 6-12 months after that, and correlated with cardiac mortality/Tx at the end of follow-up. Cox and logistic regression analyses were performed with ROC and Kaplan-Meier curves. The model was internally validated by bootstrapping. Results: There were 29 (25%) deaths/Tx during follow-up of 34.09 ± 17.9 months. Cardiac mortality/Tx was 16.3%. In the multivariate Cox model, EF < 30%, grade III/IV diastolic dysfunction and grade III mitral regurgitation at 6‑12 months were independently related to increased cardiac mortality or Tx, with hazard ratios of 3.1, 4.63 and 7.11, respectively. The area under the ROC curve was 0.78. Conclusion: EF lower than 30%, severe diastolic dysfunction and severe mitral regurgitation indicate poor prognosis 1 year after CRT. The combination of two of those variables indicate the need for other treatment options.

Resumo Fundamento: A terapia de ressincronização cardíaca (TRC) é um tratamento recomendado pelas principais diretrizes mundiais. Entretanto, 30%-40% dos pacientes selecionados não respondem ao tratamento. Objetivo: Elaborar um modelo ecocardiográfico preditor de risco de óbito cardíaco ou transplante (Tx) após 1 ano da TRC. Método: Estudo observacional, prospectivo, com inclusão de 116 pacientes, sendo 69,8% do sexo masculino, com idade de 64,89 ± 11,18 anos, CF III (68,1%) e IV ambulatorial (31,9%), bloqueio de ramo esquerdo em 71,55%, e mediana da fração de ejeção (FE) de 29%. Avaliações foram feitas no período pré-implante e 6-12 meses após, e correlacionadas com mortalidade cardíaca/Tx no final do seguimento. Foram realizadas análises de regressão de Cox e logística, com a curva ROC e de sobrevida de Kaplan-Meier. O modelo foi validado internamente pelo “bootstrapping”. Resultados: Ocorreram 29 (25%) óbitos/Tx durante o seguimento de 34,09 ± 17,9 meses. A mortalidade cardíaca/Tx foi de 16,3 %. No modelo multivariado de Cox, as variáveis FE < 30%, disfunção diastólica grau III/IV e regurgitação mitral grau III, aferidas com 6-12 meses, relacionaram-se independentemente a aumento de mortalidade cardíaca ou Tx, com razões de risco de 3,1, 4,63 e 7,11, respectivamente. A área sob a curva ROC foi de 0,78. Conclusão: FE menor que 30%, disfunção diastólica grave e regurgitação mitral severa indicam pior prognóstico após 1 ano da TRC, devendo ser consideradas outras opções terapêuticas na presença da combinação de duas dessas variáveis.

Development and Validation of Predictive Models of Cardiac Mortality and Transplantation in Resynchronization Therapy.

BACKGROUND: 30-40% of cardiac resynchronization therapy cases do not achieve favorable outcomes. OBJECTIVE: This study aimed to develop predictive models for the combined endpoint of cardiac death and transplantation (Tx) at different stages of cardiac resynchronization therapy (CRT). METHODS: Prospective observational study of 116 patients aged 64.8 ± 11.1 years, 68.1% of whom had functional class (FC) III and 31.9% had ambulatory class IV. Clinical, electrocardiographic and echocardiographic variables were assessed by using Cox regression and Kaplan-Meier curves. RESULTS: The cardiac mortality/Tx rate was 16.3% during the follow-up period of 34.0 ± 17.9 months. Prior to implantation, right ventricular dysfunction (RVD), ejection fraction < 25% and use of high doses of diuretics (HDD) increased the risk of cardiac death and Tx by 3.9-, 4.8-, and 5.9-fold, respectively. In the first year after CRT, RVD, HDD and hospitalization due to congestive heart failure increased the risk of death at hazard ratios of 3.5, 5.3, and 12.5, respectively. In the second year after CRT, RVD and FC III/IV were significant risk factors of mortality in the multivariate Cox model. The accuracy rates of the models were 84.6% at preimplantation, 93% in the first year after CRT, and 90.5% in the second year after CRT. The models were validated by bootstrapping. CONCLUSION: We developed predictive models of cardiac death and Tx at different stages of CRT based on the analysis of simple and easily obtainable clinical and echocardiographic variables. The models showed good accuracy and adjustment, were validated internally, and are useful in the selection, monitoring and counseling of patients indicated for CRT.

Development and Validation of Predictive Models of Cardiac Mortality and Transplantation in Resynchronization Therapy / Desenvolvimento e Validação de Modelos Preditores de Mortalidade Cardíaca e Transplante na Terapia de Ressincronização Cardíaca

AbstractBackground:30-40% of cardiac resynchronization therapy cases do not achieve favorable outcomes.Objective:This study aimed to develop predictive models for the combined endpoint of cardiac death and transplantation (Tx) at different stages of cardiac resynchronization therapy (CRT).Methods:Prospective observational study of 116 patients aged 64.8 ± 11.1 years, 68.1% of whom had functional class (FC) III and 31.9% had ambulatory class IV. Clinical, electrocardiographic and echocardiographic variables were assessed by using Cox regression and Kaplan-Meier curves.Results:The cardiac mortality/Tx rate was 16.3% during the follow-up period of 34.0 ± 17.9 months. Prior to implantation, right ventricular dysfunction (RVD), ejection fraction < 25% and use of high doses of diuretics (HDD) increased the risk of cardiac death and Tx by 3.9-, 4.8-, and 5.9-fold, respectively. In the first year after CRT, RVD, HDD and hospitalization due to congestive heart failure increased the risk of death at hazard ratios of 3.5, 5.3, and 12.5, respectively. In the second year after CRT, RVD and FC III/IV were significant risk factors of mortality in the multivariate Cox model. The accuracy rates of the models were 84.6% at preimplantation, 93% in the first year after CRT, and 90.5% in the second year after CRT. The models were validated by bootstrapping.Conclusion:We developed predictive models of cardiac death and Tx at different stages of CRT based on the analysis of simple and easily obtainable clinical and echocardiographic variables. The models showed good accuracy and adjustment, were validated internally, and are useful in the selection, monitoring and counseling of patients indicated for CRT.

ResumoFundamento:A terapia de ressincronização cardíaca pode demonstrar resultados desfavoráveis em 30-40% dos casos.Objetivo:Este estudo teve por objetivo desenvolver modelos preditores para o desfecho combinado de morte cardíaca ou transplante (Tx) em diferentes estágios da terapia de ressincronização cardíaca (TRC).Métodos:Estudo prospectivo observacional de 116 pacientes com idade média de 64,8 ± 11,1 anos, dos quais 68,1% estavam em classe funcional (CF) III e 31,9% em classe IV ambulatorial. Variáveis clínicas, eletrocardiográficas e ecocardiográficas foram avaliadas com regressão de Cox e curvas de Kaplan-Meier.Resultados:O desfecho mortalidade/Tx cardíacos foi de 16,3% durante seguimento de 34,0 ± 17,9 meses. No período pré-implante, disfunção ventricular direita (DVD), fração de ejeção < 25% e uso de altas doses de diuréticos (ADD) aumentaram o risco de morte e Tx cardíacos em 3,9, 4,8 e 5,9 vezes, respectivamente. No primeiro ano após TRC, DVD, AHDD e hospitalização por insuficiência cardíaca congestiva elevaram o risco de morte (razões de risco de 3,5, 5,3 e 12,5, respectivamente). No segundo ano após TRC, DVD e CF III/IV foram fatores de risco significativos de mortalidade no modelo multivariado de Cox. As acurácias dos modelos foram 84,6% na pré-implante, 93% no primeiro ano após TRC e 90,5% no segundo ano após TRC. Os modelos foram validados por bootstrapping.Conclusão:Desenvolvemos modelos preditores de morte e Tx cardíacos em diferentes estágios de TRC com base na análise de variáveis clínicas e ecocardiográficas simples e de fácil obtenção. Os modelos mostraram boa acurácia e ajuste, foram validados internamente e são úteis para a seleção, o monitoramento e a orientação de pacientes indicados para TRC.

Echocardiographic Predictors of Worse Outcome After Cardiac Resynchronization Therapy.

BACKGROUND: Cardiac resynchronization therapy (CRT) is the recommended treatment by leading global guidelines. However, 30%-40% of selected patients are non-responders. OBJECTIVE: To develop an echocardiographic model to predict cardiac death or transplantation (Tx) 1 year after CRT. METHOD: Observational, prospective study, with the inclusion of 116 patients, aged 64.89 ± 11.18 years, 69.8% male, 68,1% in NYHA FC III and 31,9% in FC IV, 71.55% with left bundle-branch block, and median ejection fraction (EF) of 29%. Evaluations were made in the pre­implantation period and 6-12 months after that, and correlated with cardiac mortality/Tx at the end of follow-up. Cox and logistic regression analyses were performed with ROC and Kaplan-Meier curves. The model was internally validated by bootstrapping. RESULTS: There were 29 (25%) deaths/Tx during follow-up of 34.09 ± 17.9 months. Cardiac mortality/Tx was 16.3%. In the multivariate Cox model, EF < 30%, grade III/IV diastolic dysfunction and grade III mitral regurgitation at 6­12 months were independently related to increased cardiac mortality or Tx, with hazard ratios of 3.1, 4.63 and 7.11, respectively. The area under the ROC curve was 0.78. CONCLUSION: EF lower than 30%, severe diastolic dysfunction and severe mitral regurgitation indicate poor prognosis 1 year after CRT. The combination of two of those variables indicate the need for other treatment options.

Long-term follow-up of patients with chronic chagas disease and implantable cardioverter-defibrillator.

BACKGROUND/OBJECTIVES: Chronic Chagas heart disease (ChHD) is associated with ventricular tachyarrhythmias and an increased risk of sudden cardiac death. Little is known about the effectiveness of implantable cardioverter-defibrillator (ICD) therapy in this population. The objective of this study was to evaluate the efficacy of ICD in patients with ChHD and to identify predictors of mortality and appropriate ICD shocks. METHODS: The cohort study included 65 patients with ChHD and ICD for primary and secondary prevention of sudden death. The Cox model was applied to evaluate the predictors of mortality, and survival was assessed by Kaplan-Meier analysis. RESULTS: The median age was 56 ± 11.9 years. The median follow-up was 40 ± 26.8 months. Among the patients 23 (36.5%) had appropriate shocks. A total of 13 (20%) patients died (6.1% of annual mortality rate), and there was no sudden death. In univariate Cox model, functional class IV (hazard ratio [HR] = 1.99; 95% confidence interval [CI], 1.05-3.76; P = 0.034), primary prevention (HR = 0.29; 95% CI, 0.09-0.99; P = 0.048), lower education (HR = 2.51; 95% CI, 1.05-5.99; P = 0.038), and ejection fraction <30% (HR = 2.80; 95% CI, 1.09-7.18; P = 0.032) were predictors of worse prognosis (death). In the multivariate Cox model, an ejection fraction <30% and the low education remained predictors of poor prognosis. Predictors of appropriate shocks were not found. CONCLUSIONS: The ICD was effective for the prevention of sudden cardiac death in patients with chronic ChHD. An ejection fraction <30% and low education were predictors of poor prognosis.