Effects of Exercise Training on Heart Rate Variability in Chagas Heart Disease / Efeitos do Treinamento Físico sobre a Variabilidade da Frequência Cardíaca na Cardiopatia Chagásica

Background: Heart rate variability (HRV) is a marker of autonomic dysfunction severity. The effects of physical training on HRV indexes in Chagas heart disease (CHD) are not well established. Objective: To evaluate the changes in HRV indexes in response to physical training in CHD. Methods: Patients with CHD and left ventricular (LV) dysfunction, physically inactive, were randomized either to the intervention (IG, N = 18) or control group (CG, N = 19). The IG participated in a 12-week exercise program consisting of 3 sessions/week. Results: Mean age was 49.5 ± 8 years, 59% males, mean LVEF was 36.3 ± 7.8%. Baseline HRV indexes were similar between groups. From baseline to follow-up, total power (TP): 1653 (IQ 625 - 3418) to 2794 (1617 - 4452) ms, p = 0.02) and very low frequency power: 586 (290 - 1565) to 815 (610 - 1425) ms, p = 0.047) increased in the IG, but not in the CG. The delta (post - pre) HRV indexes were similar: SDNN 11.5 ± 30.0 vs. 3.7 ± 25.1 ms. p = 0.10; rMSSD 2 (6 - 17) vs. 1 (21 - 9) ms. p = 0.43; TP 943 (731 - 3130) vs. 1780 (921 - 2743) Hz. p = 0.46; low frequency power (LFP) 1.0 (150 - 197) vs. 60 (111 - 146) Hz. p = 0.85; except for high frequency power, which tended to increase in the IG: 42 (133 - 92) vs. 79 (61 - 328) Hz. p = 0.08). Conclusion: In the studied population, the variation of HRV indexes was similar between the active and inactive groups. Clinical improvement with physical activity seems to be independent from autonomic dysfunction markers in CHD. .

Fundamento: A variabilidade da frequência cardíaca (VFC) é marcador de gravidade da disfunção autonômica. Os efeitos do treinamento físico sobre índices de VFC na miocardiopatia chagásica (MPC) não são bem estabelecidos. Objetivo: Avaliar as mudanças nestes índices em resposta ao treinamento físico na MPC. Métodos: Pacientes com MPC e disfunção do ventrículo esquerdo (VE), fisicamente inativos, foram aleatorizados para os grupos intervenção (GI, N = 18) e controle (GC, N = 19). O GI participou de um programa de exercícios de 12 semanas, três sessões/semana. Resultados: A idade média foi de 49,5 ± 8 anos, 59% homens, FEVE de 36,3 ± 7,8%. Índices basais de VFC foram similares. Do basal ao seguimento, observamos no GI aumento da potência total (TP): 1.653 (IQ 625 - 3.418) para 2.794 (1.617 - 4.452) ms, p = 0,02) e potência de frequência muito baixa: 586 (290 - 1.565) para 815 (610 - 1.425) ms, p = 0,047), mas não no GC. A variação (pós/pré) dos índices de VFC foi similar: SDNN 11,5 ± 30,0 vs. 3,7 ± 25, 1 ms, p = 0,10; rMSSD 2 (6 - 17) vs. 1 (21 - 9) ms, p = 0,43; TP 943 (731 - 3.130) vs. 1.780 (921 - 2.743) Hz, p = 0,46 e potência de frequência baixa (LFP) 1,0 (150 - 197) vs. 60 (111 - 146) Hz, p = 0,85, exceto pela potência de alta frequência, que teve tendência a aumento no GI: 42 (133 - 92) vs. 79 (61 - 328) Hz, p = 0,08). Conclusão: Na população estudada, a variação dos índices de VFC foi similar entre os grupos ativo e inativo. A melhora clínica com o treinamento físico parece ser independente de marcadores de disfunção autonômica na MPC. .

Effects of exercise training on heart rate variability in Chagas heart disease.

BACKGROUND: Heart rate variability (HRV) is a marker of autonomic dysfunction severity. The effects of physical training on HRV indexes in Chagas heart disease (CHD) are not well established. OBJECTIVE: To evaluate the changes in HRV indexes in response to physical training in CHD. METHODS: Patients with CHD and left ventricular (LV) dysfunction, physically inactive, were randomized either to the intervention (IG, N = 18) or control group (CG, N = 19). The IG participated in a 12-week exercise program consisting of 3 sessions/week. RESULTS: Mean age was 49.5 ± 8 years, 59% males, mean LVEF was 36.3 ± 7.8%. Baseline HRV indexes were similar between groups. From baseline to follow-up, total power (TP): 1653 (IQ 625 - 3418) to 2794 (1617 - 4452) ms, p = 0.02) and very low frequency power: 586 (290 - 1565) to 815 (610 - 1425) ms, p = 0.047) increased in the IG, but not in the CG. The delta (post - pre) HRV indexes were similar: SDNN 11.5 ± 30.0 vs. 3.7 ± 25.1 ms. p = 0.10; rMSSD 2 (6 - 17) vs. 1 (21 - 9) ms. p = 0.43; TP 943 (731 - 3130) vs. 1780 (921 - 2743) Hz. p = 0.46; low frequency power (LFP) 1.0 (150 - 197) vs. 60 (111 - 146) Hz. p = 0.85; except for high frequency power, which tended to increase in the IG: 42 (133 - 92) vs. 79 (61 - 328) Hz. p = 0.08). CONCLUSION: In the studied population, the variation of HRV indexes was similar between the active and inactive groups. Clinical improvement with physical activity seems to be independent from autonomic dysfunction markers in CHD.

[Right-side infective endocarditis: discrepancy between clinical and echocardiographic evolution: case report]. / Endocardite infecciosa em câmaras direitas: discrepância entre evolução clínica e ecocardiográfica: relato de caso.

Infective endocarditis is a relatively rare disease in clinical practice, with significant morbidity and mortality despite the improvements on its diagnosis and treatment. It is often difficult to identify its complications and define strategies for them. Dissociation between the clinical evolution and the findings from complementary tests (especially echocardiographic tests) is common. Clinical decisions become even more difficult when there are atypical manifestations of the disease, such as right-side endocarditis. This report is about a rare case of right-side endocarditis in a patient with chronic renal disease, in which there was a contradiction between worsening of the echocardiographic findings and clinical improvement. This situation may lead to difficulties regarding the criteria for indicating surgery and the safety of conservative clinical treatment.

Endocardite infecciosa em câmaras direitas: discrepância entre evolução clínica e ecocardiográfica: relato de caso / Right-side infective endocarditis: discrepancy between clinical and echocardiographic evolution: case report

A endocardite infecciosa é uma patologia relativamente rara na prática clínica, e, apesar dos avanços em seu diagnóstico e tratamento, sua morbi-mortalidade ainda é significativa. Muitas vezes é difícil a identificação de suas complicações e a conduta frente a elas, ocorrendo com freqüência a dissociação entre a evolução clínica e os achados de exames complementares - principalmente ecocardiográficos. A decisão clínica torna-se ainda mais difícil frente às manifestações atípicas da doença, como a endocardite de câmaras direitas. Este é o relato de um caso raro de endocardite de câmaras direitas em uma paciente renal crônica, cuja piora dos achados ecocardiográficos se opunha à evolução clínica favorável. Esta situação pode suscitar dificuldade quanto aos critérios para indicação cirúrgica e a segurança do tratamento conservador.

Infective endocarditis is a relatively rare disease in clinical practice, with significant morbidity and mortality despite the improvements on its diagnosis and treatment. It is often difficult to identify its complications and define strategies for them. Dissociation between the clinical evolution and the findings from complementary tests (especially echocardiographic tests) is common. Clinical decisions become even more difficult when there are atypical manifestations of the disease, such as right-side endocarditis. This report is about a rare case of right-side endocarditis in a patient with chronic renal disease, in which there was a contradiction between worsening of the echocardiographic findings and clinical improvement. This situation may lead to difficulties regarding the criteria for indicating surgery and the safety of conservative clinical treatment.