Daniela Bassi

Effects of aerobic exercise training on variability and heart rate kinetic during submaximal exercise after gastric bypass surgery – a randomized controlled trial

Background: This study aimed to determine whether morbidly obese women have an alteration of heart rate (HR) kinetics and HR variability (HRV) during the 6-min walk test (6MWT) and if an aerobic exercise training can modify these indexes after gastric bypass surgery (GBS). Design and methods: Nineteen morbidly obese women were randomized to a trained (TG) or control group and 12 women of eutrophic group (EG) were also evaluated. The obese women were tested on two occasions: 1 week before and 4 months after GBS through record of HR and R-R intervals during 6MWT for analysis HR kinetics. The TG underwent an aerobic exercise training program on a treadmill (1-h session, totaling 36 sessions over 12-week). Results: Both obese groups demonstrated a significant reduction of rMSSD and slower HR kinetics during the 6MWT when compared to the EG. In addition, only the TG demonstrated a significant improvement in HRV indexes, walking distance, faster time constant and mean response time of HR during 6MWT after training (p < 0.05). Conclusion: Morbidly obese women have slower HR kinetics and altered cardiac modulation during submaximal exercise. However, aerobic exercise training can produce beneficial adaptations in HRV and faster HR kinetics following GBS. Implications for Rehabilitation The obesity is one of the most important threats to health in developed countries and bariatric surgery is an option for treatment of morbid obesity. Exercise is an effective means of improving health after this procedure due alterations of autonomic nervous system in this population. This study showed that a program of aerobic physical training after bariatric surgery was able to improve the kinetics of heart rate and the cardiac autonomic modulation, both evaluated during submaximal exercise.

Hemodynamic, Autonomic, Ventilatory, and Metabolic Alterations After Resistance Training in Patients With Coronary Artery Disease: A Randomized Controlled Trial

Objective The aim of this work was to evaluate the hemodynamic, autonomic, and metabolic responses during resistance and dynamic exercise before and after an 8-week resistance training program using a low-intensity (30% of 1 repetitium maximum), high-repetition (3 sets of 20 repetitions) model, added to an aerobic training program, in a coronary artery disease cohort. Design Twenty male subjects with coronary artery disease (61.1 ± 4.7 years) were randomly assigned to a combined training group (resistance + aerobic) or aerobic training group (AG). Heart rate, stroke volume, cardiac output, minute ventilation, blood lactate, and parasympathetic modulation indices of heart rate (square root of the mean squared differences of successive RR intervals [RMSSD] and dispersion of points perpendicular to the line of identity that provides information about the instantaneous beat-to-beat variability [SD1]) were obtained before and after an 8-week RT program while performing exercise on a cycle ergometer and a 45-degree leg press. Results Resistance training resulted in an increase in maximal and submaximal load tolerance (P < 0.01), a decreased hemodynamic response (P < 0.01), and a reduction in blood lactate in the combined training group compared to the aerobic training group during the 45-degree leg press. During exercise on a cycle ergometer, there was a decreased hemodynamic response and increased minute ventilation (P < 0.01). The 8-week RT program resulted in greater parasympathetic tone (RMSSD and SD1) and an increase in the SDNN index during exercise on a cycle ergometer and 45-degree leg press (P < 0.05). Conclusions An 8-week resistance training program associated with aerobic training may attenuate hemodynamic stress, and modify metabolic and autonomic responses during resistance exercise. The training program also appeared to elicit beneficial cardiovascular and autonomic effects during exercise.

Poor glycemic control impacts linear and non-linear dynamics of heart rate in DM type 2

INTRODUCAO: E de conhecimento geral que o diabetes mellitus tipo 2 (DM2) produz neuropatia autonomica cardiovascular (NAC), que pode afetar a modulacao autonomica cardiaca. Entretanto, nao e claro se a falta de controle glicemico em diabeticos tipo 2 sem NAC, poderia impactar negativamente na modulacao autonomica cardiaca. Objetivo: Avaliar a relacao entre controle glicemico e modulacao autonomica cardiaca em individuos com DM2 sem neuropatia autonomica cardiovascular. Estudo descritivo, prospectivo e transversal. METODOS: Quarenta e nove pacientes com DM2 (51±7 anos) foram divididos em dois grupos de acordo com a hemoglobina glicosilada (HbA1c): G1: ≤ 7% e G2: >7,0%. A frequencia cardiaca de repouso (FC) e intervalo RR (iRR) foram obtidos e calculados por metodos lineares (media iRR; media FC; rMSSD; STD RR; LF; HF; LF/HF, TINN e RR Tri) e nao lineares (SD1; SD2; DFα1; DFα2, Entropia de Shannon; ApEn; SampEn e CD) de variabilidade de frequencia cardiaca. Insulina, HOMA-IR, glicemia de jejum e HbA1c foram obtidas por analises sanguineas. RESULTADOS: G2 (HbA1c ≤ 7%) mostrou valores menores para media de iRR; STD RR; RR Tri, TINN, SD2, CD e maiores para media de FR quando comparado com G1 (HbA1c > 7%). Adicionalmente, HbA1c correlacionou-se negativamente com media iRR (r=0,28, p=0,044); STD RR (r=0,33, p=0,017); RR Tri (r=-0,35, p=0,013), SD2 (r=-0,39, p=0,004) e positivamente com media FC (r=0,28, p=0,045). Finalmente, a glicemia de jejum correlacionou-se negativamente com STD RR (r=-0,36, p=0,010); RR Tri (r=-0,36, p=0,010); TINN (r=-0,33, p=0,019) e SD2 (r=-0,42, p=0,002). CONCLUSAO: Conclui que o controle glicemico deficiente relaciona-se com indices de modulacao autonomica cardiaca em individuos com DM2, ainda que nao apresentem neuropatia autonomica cardiovascular.INTRODUCCION: Es de conocimiento general que la diabetes mellitus tipo 2 (DM2) produce neuropatia autonomica cardiovascular (NAC), que puede afectar la modulacion autonomica cardiaca. Entretanto, no es claro si la falta de control glucemico en diabeticos tipo 2 sin NAC, podria impactar negativamente en la modulacion autonomica cardiaca. Objetivo: Evaluar la relacion entre control glucemico y modulacion autonomica cardiaca en individuos con DM2 sin neuropatia autonomica cardiovascular. Estudio descriptivo, prospectivo y transversal. METODOS: Cuarenta y nueve pacientes con DM2 (51±7 anos) fueron divididos en dos grupos de acuerdo con la hemoglobina glucosilada (HbA1c): G1: ≤ 7% y G2: >7,0%. La frecuencia cardiaca de reposo (FC) e intervalo RR (iRR) fueron obtenidos y calculados por metodos lineales (promedio iRR; promedio FC; rMSSD; STD RR; LF; HF; LF/HF, TINN y RR Tri) y no lineales (SD1; SD2; DFα1; DFα2, Entropia de Shannon; ApEn; SampEn y CD) de variabilidad de frecuencia cardiaca. Fueron obtenidas insulina, HOMA-IR, glucemia en ayunas y HbA1c a traves de analisis sanguineos. RESULTADOS: G2 (HbA1c ≤ 7%) mostro valores menores para el promedio de iRR; STD RR; RR Tri, TINN, SD2, CD y mayores para el promedio de FR al ser comparado con G1 (HbA1c > 7%). Adicionalmente, HbA1c se correlaciono negativamente con el promedio iRR (r=0,28, p=0,044); STD RR (r=0,33, p=0,017); RR Tri (r=-0,35, p=0,013), SD2 (r=-0,39, p=0,004) y positivamente con el promedio FC (r=0,28, p=0,045). Finalmente, la glucemia en ayunas se correlaciono negativamente con STD RR (r=-0,36, p=0,010); RR Tri (r=-0,36, p=0,010); TINN (r=-0,33, p=0,019) e SD2 (r=-0,42, p=0,002). CONCLUSION: Concluimos que el control glucemico deficiente se relaciona con indices de modulacion autonomica cardiaca en individuos con DM2, aunque no presenten neuropatia autonomica cardiovascular.

Efeitos da Coexistência de Diabetes Tipo 2 e Hipertensão sobre a Variabilidade da Frequência Cardíaca e Capacidade Cardiorrespiratória

Background Type 2 diabetes Mellitus (T2DM) is associated with cardiac autonomic dysfunction, which is an independent predictor of mortality in chronic diseases. However, whether the coexistence of systemic arterial hypertension (HTN) with DMT2 alters cardiac autonomic modulation remains unknown. Objective To evaluate the influence of HTN on cardiac autonomic modulation and cardiorespiratory fitness in subjects with DMT2. Methods 60 patients of both genders were evaluated and allocated to two groups: DMT2 patients (n = 32; 51 ± 7.5 years old) and DMT2 + HTN patients (n = 28; 51 ± 6.9 years old). RR intervals were obtained during rest in supine position. Linear and nonlinear indices of heart rate variability (HRV) were computed using Kubios HRV software. Pulmonary gas exchange was measured breath-by-breath, using a portable telemetric system during maximal incremental exercise testing on a cycle ergometer. Statistical analysis included Shapiro-Wilk test followed by Student’s t Test, Pearson correlation and linear regression. Results We found that patients in the DMT2+HTN group showed lower values of mean RR intervals (801.1 vs 871.5 ms), Shannon entropy (3 vs 3.2) and fractal dimension SD 1 (9.5 vs 14.5), when contrasted with patients in the DMT2 group. Negative correlations were found between some HRV nonlinear indices and exercise capacity indices. Conclusion HTN negatively affects the cardiac autonomic function in diabetic patients, who are already prone to develop autonomic dysfunction. Strategies are need to improve cardiac autonomic functionality in this population.

Pobre controle glicêmico impacta a dinâmica linear e não linear da frequência cardíaca no DM2

INTRODUCAO: E de conhecimento geral que o diabetes mellitus tipo 2 (DM2) produz neuropatia autonomica cardiovascular (NAC), que pode afetar a modulacao autonomica cardiaca. Entretanto, nao e claro se a falta de controle glicemico em diabeticos tipo 2 sem NAC, poderia impactar negativamente na modulacao autonomica cardiaca. Objetivo: Avaliar a relacao entre controle glicemico e modulacao autonomica cardiaca em individuos com DM2 sem neuropatia autonomica cardiovascular. Estudo descritivo, prospectivo e transversal. METODOS: Quarenta e nove pacientes com DM2 (51±7 anos) foram divididos em dois grupos de acordo com a hemoglobina glicosilada (HbA1c): G1: ≤ 7% e G2: >7,0%. A frequencia cardiaca de repouso (FC) e intervalo RR (iRR) foram obtidos e calculados por metodos lineares (media iRR; media FC; rMSSD; STD RR; LF; HF; LF/HF, TINN e RR Tri) e nao lineares (SD1; SD2; DFα1; DFα2, Entropia de Shannon; ApEn; SampEn e CD) de variabilidade de frequencia cardiaca. Insulina, HOMA-IR, glicemia de jejum e HbA1c foram obtidas por analises sanguineas. RESULTADOS: G2 (HbA1c ≤ 7%) mostrou valores menores para media de iRR; STD RR; RR Tri, TINN, SD2, CD e maiores para media de FR quando comparado com G1 (HbA1c > 7%). Adicionalmente, HbA1c correlacionou-se negativamente com media iRR (r=0,28, p=0,044); STD RR (r=0,33, p=0,017); RR Tri (r=-0,35, p=0,013), SD2 (r=-0,39, p=0,004) e positivamente com media FC (r=0,28, p=0,045). Finalmente, a glicemia de jejum correlacionou-se negativamente com STD RR (r=-0,36, p=0,010); RR Tri (r=-0,36, p=0,010); TINN (r=-0,33, p=0,019) e SD2 (r=-0,42, p=0,002). CONCLUSAO: Conclui que o controle glicemico deficiente relaciona-se com indices de modulacao autonomica cardiaca em individuos com DM2, ainda que nao apresentem neuropatia autonomica cardiovascular.INTRODUCCION: Es de conocimiento general que la diabetes mellitus tipo 2 (DM2) produce neuropatia autonomica cardiovascular (NAC), que puede afectar la modulacion autonomica cardiaca. Entretanto, no es claro si la falta de control glucemico en diabeticos tipo 2 sin NAC, podria impactar negativamente en la modulacion autonomica cardiaca. Objetivo: Evaluar la relacion entre control glucemico y modulacion autonomica cardiaca en individuos con DM2 sin neuropatia autonomica cardiovascular. Estudio descriptivo, prospectivo y transversal. METODOS: Cuarenta y nueve pacientes con DM2 (51±7 anos) fueron divididos en dos grupos de acuerdo con la hemoglobina glucosilada (HbA1c): G1: ≤ 7% y G2: >7,0%. La frecuencia cardiaca de reposo (FC) e intervalo RR (iRR) fueron obtenidos y calculados por metodos lineales (promedio iRR; promedio FC; rMSSD; STD RR; LF; HF; LF/HF, TINN y RR Tri) y no lineales (SD1; SD2; DFα1; DFα2, Entropia de Shannon; ApEn; SampEn y CD) de variabilidad de frecuencia cardiaca. Fueron obtenidas insulina, HOMA-IR, glucemia en ayunas y HbA1c a traves de analisis sanguineos. RESULTADOS: G2 (HbA1c ≤ 7%) mostro valores menores para el promedio de iRR; STD RR; RR Tri, TINN, SD2, CD y mayores para el promedio de FR al ser comparado con G1 (HbA1c > 7%). Adicionalmente, HbA1c se correlaciono negativamente con el promedio iRR (r=0,28, p=0,044); STD RR (r=0,33, p=0,017); RR Tri (r=-0,35, p=0,013), SD2 (r=-0,39, p=0,004) y positivamente con el promedio FC (r=0,28, p=0,045). Finalmente, la glucemia en ayunas se correlaciono negativamente con STD RR (r=-0,36, p=0,010); RR Tri (r=-0,36, p=0,010); TINN (r=-0,33, p=0,019) e SD2 (r=-0,42, p=0,002). CONCLUSION: Concluimos que el control glucemico deficiente se relaciona con indices de modulacion autonomica cardiaca en individuos con DM2, aunque no presenten neuropatia autonomica cardiovascular.

Control glucémico deficiente impacta la dinámica lineal y no lineal de la frecuencia cardíaca en el DM2

INTRODUCAO: E de conhecimento geral que o diabetes mellitus tipo 2 (DM2) produz neuropatia autonomica cardiovascular (NAC), que pode afetar a modulacao autonomica cardiaca. Entretanto, nao e claro se a falta de controle glicemico em diabeticos tipo 2 sem NAC, poderia impactar negativamente na modulacao autonomica cardiaca. Objetivo: Avaliar a relacao entre controle glicemico e modulacao autonomica cardiaca em individuos com DM2 sem neuropatia autonomica cardiovascular. Estudo descritivo, prospectivo e transversal. METODOS: Quarenta e nove pacientes com DM2 (51±7 anos) foram divididos em dois grupos de acordo com a hemoglobina glicosilada (HbA1c): G1: ≤ 7% e G2: >7,0%. A frequencia cardiaca de repouso (FC) e intervalo RR (iRR) foram obtidos e calculados por metodos lineares (media iRR; media FC; rMSSD; STD RR; LF; HF; LF/HF, TINN e RR Tri) e nao lineares (SD1; SD2; DFα1; DFα2, Entropia de Shannon; ApEn; SampEn e CD) de variabilidade de frequencia cardiaca. Insulina, HOMA-IR, glicemia de jejum e HbA1c foram obtidas por analises sanguineas. RESULTADOS: G2 (HbA1c ≤ 7%) mostrou valores menores para media de iRR; STD RR; RR Tri, TINN, SD2, CD e maiores para media de FR quando comparado com G1 (HbA1c > 7%). Adicionalmente, HbA1c correlacionou-se negativamente com media iRR (r=0,28, p=0,044); STD RR (r=0,33, p=0,017); RR Tri (r=-0,35, p=0,013), SD2 (r=-0,39, p=0,004) e positivamente com media FC (r=0,28, p=0,045). Finalmente, a glicemia de jejum correlacionou-se negativamente com STD RR (r=-0,36, p=0,010); RR Tri (r=-0,36, p=0,010); TINN (r=-0,33, p=0,019) e SD2 (r=-0,42, p=0,002). CONCLUSAO: Conclui que o controle glicemico deficiente relaciona-se com indices de modulacao autonomica cardiaca em individuos com DM2, ainda que nao apresentem neuropatia autonomica cardiovascular.INTRODUCCION: Es de conocimiento general que la diabetes mellitus tipo 2 (DM2) produce neuropatia autonomica cardiovascular (NAC), que puede afectar la modulacion autonomica cardiaca. Entretanto, no es claro si la falta de control glucemico en diabeticos tipo 2 sin NAC, podria impactar negativamente en la modulacion autonomica cardiaca. Objetivo: Evaluar la relacion entre control glucemico y modulacion autonomica cardiaca en individuos con DM2 sin neuropatia autonomica cardiovascular. Estudio descriptivo, prospectivo y transversal. METODOS: Cuarenta y nueve pacientes con DM2 (51±7 anos) fueron divididos en dos grupos de acuerdo con la hemoglobina glucosilada (HbA1c): G1: ≤ 7% y G2: >7,0%. La frecuencia cardiaca de reposo (FC) e intervalo RR (iRR) fueron obtenidos y calculados por metodos lineales (promedio iRR; promedio FC; rMSSD; STD RR; LF; HF; LF/HF, TINN y RR Tri) y no lineales (SD1; SD2; DFα1; DFα2, Entropia de Shannon; ApEn; SampEn y CD) de variabilidad de frecuencia cardiaca. Fueron obtenidas insulina, HOMA-IR, glucemia en ayunas y HbA1c a traves de analisis sanguineos. RESULTADOS: G2 (HbA1c ≤ 7%) mostro valores menores para el promedio de iRR; STD RR; RR Tri, TINN, SD2, CD y mayores para el promedio de FR al ser comparado con G1 (HbA1c > 7%). Adicionalmente, HbA1c se correlaciono negativamente con el promedio iRR (r=0,28, p=0,044); STD RR (r=0,33, p=0,017); RR Tri (r=-0,35, p=0,013), SD2 (r=-0,39, p=0,004) y positivamente con el promedio FC (r=0,28, p=0,045). Finalmente, la glucemia en ayunas se correlaciono negativamente con STD RR (r=-0,36, p=0,010); RR Tri (r=-0,36, p=0,010); TINN (r=-0,33, p=0,019) e SD2 (r=-0,42, p=0,002). CONCLUSION: Concluimos que el control glucemico deficiente se relaciona con indices de modulacion autonomica cardiaca en individuos con DM2, aunque no presenten neuropatia autonomica cardiovascular.

Glycemic control affecting the autonomic modulation in type 2 diabetes

Materials and methods We evaluated 49 patients (51.2±7.7 yrs.) with a confirmed diagnosis of diabetes. The subjects were randomized in two groups according to glycated hemoglobin-HbA1c: HbA1c 7%. The fasting plasma glucose and HbA1c were performed in a specialized laboratory and HR and iRR were recorded for 10 min in the supine position. Statistical analysis included Shapiro-Wilk Test, Mann Whitney Test and Spearman Correlation.