Functional Capacity of Patients with Pacemaker Due to Isolated Congenital Atrioventricular Block / Capacidade Funcional de Portadores de Marca-Passo por Bloqueio Atrioventricular Congênito Isolado

Background: Isolated congenital atrioventricular block (CAVB) is a rare condition with multiple clinical outcomes. Ventricular remodeling can occur in approximately 10% of the patients after pacemaker (PM) implantation. Objectives: To assess the functional capacity of children and young adults with isolated CAVB and chronic pacing of the right ventricle (RV) and evaluate its correlation with predictors of ventricular remodeling. Methods: This cross-sectional study used a cohort of patients with isolated CAVB and RV pacing for over a year. The subjects underwent clinical and echocardiographic evaluation. Functional capacity was assessed using the six-minute walk test. Chi-square test, Fisher's exact test, and Pearson correlation coefficient were used, considering a significance level of 5%. Results: A total of 61 individuals were evaluated between March 2010 and December 2013, of which 67.2% were women, aged between 7 and 41 years, who were using PMs for 13.5 ± 6.3 years. The percentage of ventricular pacing was 97.9 ± 4.1%, and the duration of the paced QRS complex was 153.7 ± 19.1 ms. Majority of the subjects (95.1%) were asymptomatic and did not use any medication. The mean distance walked was 546.9 ± 76.2 meters and was strongly correlated with the predicted distance (r = 0.907, p = 0.001) but not with risk factors for ventricular remodeling. (Arq Bras Cardiol. 2014; [online].ahead print, PP.0-0) Conclusions: The functional capacity of isolated CAVB patients with chronic RV pacing was satisfactory but did not correlate with risk factors for ventricular remodeling. .

Fundamento: O bloqueio atrioventricular congênito isolado (BAVCi) é raro e tem múltiplas apresentações clínicas. O remodelamento ventricular pode ocorrer em cerca de 10% dos indivíduos após o implante de marca-passo. Objetivos: Avaliar a capacidade funcional de crianças e adultos jovens com BAVCi e estimulação crônica no ventrículo direito (VD) e pesquisar sua associação com fatores preditores de remodelamento ventricular. Métodos: Estudo transversal em coorte de indivíduos com BAVCi e estimulação no VD há mais de um ano. Os indivíduos foram submetidos a avaliação clínica e ecocardiográfica. A capacidade funcional foi avaliada pelo teste de caminhada de seis minutos. Foram empregados os testes qui-quadrado, exato de Fisher e coeficiente de correlação de Pearson, considerando o nível de significância de 5%. Resultados: De março de 2010 a dezembro de 2013, foram avaliados 61 indivíduos, 67,2% do sexo feminino, com 7-41 anos de idade e uso de MP há 13,5 ± 6,3 anos. O percentual de estimulação ventricular era 97,9 ± 4,1% e a duração do complexo QRS estimulado era de 153,7 ± 19,1 ms. A maioria (95,1%) era assintomática e não utilizava medicamentos. A distância média percorrida de 546,9 ± 76,2 m teve forte correlação com a distância predita (r = 0,907; p = 0,001) e não se associou com os fatores de risco de remodelamento estudados. Conclusões: A capacidade funcional de portadores de BAVTCi com estimulação crônica no VD foi satisfatória e não se correlacionou com os fatores de risco para remodelamento ventricular. .

Functional capacity of patients with pacemaker due to isolated congenital atrioventricular block.

BACKGROUND: Isolated congenital atrioventricular block (CAVB) is a rare condition with multiple clinical outcomes. Ventricular remodeling can occur in approximately 10% of the patients after pacemaker (PM) implantation. OBJECTIVES: To assess the functional capacity of children and young adults with isolated CAVB and chronic pacing of the right ventricle (RV) and evaluate its correlation with predictors of ventricular remodeling. METHODS: This cross-sectional study used a cohort of patients with isolated CAVB and RV pacing for over a year. The subjects underwent clinical and echocardiographic evaluation. Functional capacity was assessed using the six-minute walk test. Chi-square test, Fisher's exact test, and Pearson correlation coefficient were used, considering a significance level of 5%. RESULTS: A total of 61 individuals were evaluated between March 2010 and December 2013, of which 67.2% were women, aged between 7 and 41 years, who were using PMs for 13.5 ± 6.3 years. The percentage of ventricular pacing was 97.9 ± 4.1%, and the duration of the paced QRS complex was 153.7 ± 19.1 ms. Majority of the subjects (95.1%) were asymptomatic and did not use any medication. The mean distance walked was 546.9 ± 76.2 meters and was strongly correlated with the predicted distance (r = 0.907, p = 0.001) but not with risk factors for ventricular remodeling. (Arq Bras Cardiol. 2014; [online].ahead print, PP.0-0) CONCLUSIONS: The functional capacity of isolated CAVB patients with chronic RV pacing was satisfactory but did not correlate with risk factors for ventricular remodeling.

Avaliação da estimulação ventricular direita crônica em crianças e adultos jovens com bloqueio atrioventricular congênito isolado / Evaluation of chronic right ventricular pacing in children and young adults with isolated congenital complete atrioventricular block

Introdução: O bloqueio atrioventricular congênito isolado (BAVCi) é raro e tem múltiplas apresentações clínicas. O implante de marca-passo cardíaco permanente (MP) é o tratamento de escolha, resultando em evolução clínica satisfatória para a maioria dos casos, porém, aproximadamente 10% deles apresentam remodelamento ventricular e insuficiência cardíaca grave. Objetivos: Estudar a evolução tardia de crianças e adultos jovens com BAVCi e estimulação crônica do ventrículo direito (VD), visando determinar: a prevalência de sinais clínicos e laboratoriais de insuficiência cardíaca e de remodelamento ventricular; a capacidade funcional; a qualidade de vida e fatores preditores de alterações clínicas, funcionais ou ecocardiográficas. Métodos: Estudo transversal realizado em coorte de portadores de BAVCi e MP implantado antes de 21 anos de idade com estimulação no VD há mais de um ano. Todos os indivíduos foram submetidos a avaliação clínica e laboratorial, da capacidade funcional, da qualidade de vida e a ecocardiograma. Mães e sujeitos da pesquisa foram investigados para doenças reumatológicas. Os dados foram armazenados no sistema REDCap (Research Electronic Data Capture) e analisados pelos programas SAS (Statistical Analysis System), SPSS (Statistical Package for the Social Sciences) e R Studio. A análise dos dados incluiu: análise univariada para pesquisa de associações entre variáveis preditoras e desfechos, coeficiente de correlação de Pearson e modelo de regressão linear multivariado. Resultados: De março/2010 a dezembro/2013, foram avaliados 63 indivíduos, 68% do sexo feminino, com idade de 1 a 40 anos, com MP por 13,4 ± 6,5 anos e estimulação do VD por 10,0 ± 5,4 anos. O modo de estimulação era atrioventricular em 55,6%, o percentual de estimulação de VD de 97,9 ± 4,2% e a duração do complexo QRS estimulado de 152,4 ± 20,1 ms. A maioria (88,9%) era assintomática e não utilizava medicamentos de ação cardiovascular. Maior tempo de MP...

Introduction: Isolated congenital atrioventricular block (iCAVB) is a rare condition with multiple clinical presentations. Permanent cardiac pacing is the most effective therapy for this population resulting in satisfactory long-term outcomes. However, approximately 10% of patients may have ventricular remodeling and severe heart failure. Objectives: To study the long-term effects of chronic right ventricular (RV) pacing in children and young adults with iCAVB in order to determine: prevalence of clinical and laboratory signs of heart failure and ventricular remodeling, functional capacity, quality of life and predictors of clinical, functional or echocardiographic abnormalities. Methods: Cross-sectional study of a cohort of iCAVB patients with <= 21 years old at initial pacemaker (PM) implantation and single or dual-chamber pacing in a unique RV site for a minimum of one year. All subjects underwent clinical and laboratory assessment, functional capacity, quality of life and echocardiogram. Mothers and research subjects were investigated for rheumatic diseases. Data were stored in REDCap (Research Electronic Data Capture) system and analyzed by SAS (Statistical Analysis System), SPSS (Statistical Package for the Social Sciences) and R Studio programs. Data analysis included: univariate analysis for associations between predictor variables and outcomes, Pearson correlation coefficient and linear regression multivariate model. Results: Between March/2010 and December/2013, we evaluated 63 subjects aged 1-40 years old, 68% female, under PM for 13.4 ± 6.5 years and under RV pacing for 10.0 ± 5.4 years. Pacing mode was atrioventricular in 55.6%, percentage of RV pacing was 97.9 ± 4.2% and paced QRS duration was 152.4 ± 20.1 ms. Overall, the majority (88.9%) were asymptomatic and did not use cardiovascular drugs. Longer time under PM (P= 0.013), or even under RV pacing (P= 0.005), higher age at study inclusion (P= 0.032) and lower left ventricular...

Implantable cardioverter-defibrillator in pregnant women with hypertrophic cardiomyopathy.

We describe the successful implantation of a cardioverter-defibrillator (ICD) in two pregnant women with hypertrophic cardiomyopathy at high risk. The indication of ICD and the necessary care for ICD implantation during pregnancy are discussed and were the main objectives of this case report.

Implante de cardio-desfibrilador em gestantes com cardiomiopatia hipertrófica / Implantable cardioverter-defibrillator in pregnant women with hypertrophic cardiomyopathy

Descrevemos os casos de duas gestantes portadoras de cardiomiopatia hipertrófica com alto risco de morte súbita arrítmica, que foram submetidas a implante de cardioversor-desfibrilador automático (CDI) no intercurso da gestação. O momento para a realização do procedimento e os cuidados necessários para o implante do CDI durante a gestação são discutidos e foram os principais objetivos deste relato.

We describe the successful implantation of a cardioverter-defibrillator (ICD) in two pregnant women with hypertrophic cardiomyopathy at high risk. The indication of ICD and the necessary care for ICD implantation during pregnancy are discussed and were the main objectives of this case report.