Risk factors for inspiratory muscle weakness in chronic heart failure

BACKGROUND: Chronic heart failure is commonly associated with inspiratory muscle weakness. However, few studies have investigated the risk factors for inspiratory muscle weakness in individuals with chronic heart failure and systolic dysfunction (left-ventricular ejection fraction [LVEF] <40%). METHODS: Seventy subjects were recruited in a cardiac center. We assessed clinical parameters, smoking history, peripheral muscle strength, pulmonary function, echocardiographic variables, and brain natriuretic peptide. The subjects were classified with inspiratory muscle weakness when the maximum inspiratory pressure was <70% of predicted values. RESULTS: Thirty-six subjects (51%) had inspiratory muscle weakness. The subjects with inspiratory muscle weakness and the subjects with no inspiratory muscle weakness were similar in age, sex, body mass index, medication use, and physical activity. However, the subjects with inspiratory muscle weakness had lower LVEF (P = .003), systolic blood pressure (P = .01), diastolic blood pressure (P = .042), quadriceps muscle strength (P = .02), lung function (P = .035), increased brain natriuretic peptide (P = .02), smoking history (P = .01), and pulmonary hypertension incidence (P = .03). Multivariate logistic regression analysis found a lower LVEF, increased smoking history, and lower systolic blood pressure as significant independent predictors for inspiratory muscle weakness. CONCLUSIONS: The combination of lower LVEF, lower systolic blood pressure, and smoking history predicted inspiratory muscle weakness. Patients with suspected inspiratory muscle weakness should be examined and, if inspiratory muscle weakness exists, then inspiratory muscle training should be provided. Reducing inspiratory muscle weakness has the potential to improve many of the deleterious effects of chronic heart failure. (AU)

Risk Factors for Inspiratory Muscle Weakness in Chronic Heart Failure.

BACKGROUND: Chronic heart failure is commonly associated with inspiratory muscle weakness. However, few studies have investigated the risk factors for inspiratory muscle weakness in individuals with chronic heart failure and systolic dysfunction (left-ventricular ejection fraction [LVEF] <40%). METHODS: Seventy subjects were recruited in a cardiac center. We assessed clinical parameters, smoking history, peripheral muscle strength, pulmonary function, echocardiographic variables, and brain natriuretic peptide. The subjects were classified with inspiratory muscle weakness when the maximum inspiratory pressure was <70% of predicted values. RESULTS: Thirty-six subjects (51%) had inspiratory muscle weakness. The subjects with inspiratory muscle weakness and the subjects with no inspiratory muscle weakness were similar in age, sex, body mass index, medication use, and physical activity. However, the subjects with inspiratory muscle weakness had lower LVEF (P = .003), systolic blood pressure (P = .01), diastolic blood pressure (P = .042), quadriceps muscle strength (P = .02), lung function (P = .035), increased brain natriuretic peptide (P = .02), smoking history (P = .01), and pulmonary hypertension incidence (P = .03). Multivariate logistic regression analysis found a lower LVEF, increased smoking history, and lower systolic blood pressure as significant independent predictors for inspiratory muscle weakness. CONCLUSIONS: The combination of lower LVEF, lower systolic blood pressure, and smoking history predicted inspiratory muscle weakness. Patients with suspected inspiratory muscle weakness should be examined and, if inspiratory muscle weakness exists, then inspiratory muscle training should be provided. Reducing inspiratory muscle weakness has the potential to improve many of the deleterious effects of chronic heart failure.

Is there any benefit using low-intensity inspiratory and peripheral muscle training in heart failure? A randomized clinical trial.

BACKGROUND: Inspiratory and peripheral muscle training improves muscle strength, exercise tolerance, and quality of life in patients with chronic heart failure (HF). However, studies investigating different workloads for these exercise modalities are still lacking. OBJECTIVE: To examine the effects of low and moderate intensities on muscle strength, functional capacity, and quality of life. DESIGN: A randomized controlled trial. METHODS: Thirty-five patients with stable HF (aged >18 years, NYHA II/III, LVEF <40%) were randomized to: non-exercise control group (n = 9), low-intensity training group (LIPRT, n = 13, 15% maximal inspiratory workload, and 0.5 kg of peripheral muscle workload) or moderate-intensity training group (MIPRT, n = 13, 30% maximal inspiratory workload and 50% of one maximum repetition of peripheral muscle workload). The outcomes were: respiratory and peripheral muscle strength, pulmonary function, exercise tolerance by the 6-minute walk test, symptoms based on the NYHA functional class, and quality of life using the Minnesota Living with Heart Failure Questionnaire. RESULTS: All groups showed similar quality-of-life improvements. Low and moderate intensities training programs improved inspiratory muscle strength, peripheral muscle strength, and walking distance. However, only moderate intensity improved expiratory muscle strength and NYHA functional class in HF patients. CONCLUSIONS: The low-intensity inspiratory and peripheral resistance muscle training improved inspiratory and peripheral muscle strength and walking distance, demonstrating that LIPRT is an efficient rehabilitation method for debilitated HF patients. In addition, the moderate-intensity resistance training also improved expiratory muscle strength and NYHA functional class in HF patients.

Is there any benefit using low-intensity inspiratory and peripheral muscle training in heart failure? A randomized clinical trial

BACKGROUND: Inspiratory and peripheral muscle training improves muscle strength, exercise tolerance, and quality of life in patients with chronic heart failure (HF). However, studies investigating different workloads for these exercise modalities are still lacking. OBJECTIVE: To examine the effects of low and moderate intensities on muscle strength, functional capacity, and quality of life. DESIGN: A randomized controlled trial.METHODS:Thirty-five patients with stable HF (aged >18 years, NYHA II/III, LVEF <40%) were randomized to: non-exercise control group (n = 9), low-intensity training group (LIPRT, n = 13, 15% maximal inspiratory workload, and 0.5 kg of peripheral muscle workload) or moderate-intensity training group (MIPRT, n = 13, 30% maximal inspiratory workload and 50% of one maximum repetition of peripheral muscle workload). The outcomes were: respiratory and peripheral muscle strength, pulmonary function, exercise tolerance by the 6-minute walk test, symptoms based on the NYHA functional class, and quality of life using the Minnesota Living with Heart Failure Questionnaire...

Reproducibility for Heart Rate Variability Analysis during 6-Min Walk Test in Patients with Heart Failure and Agreement between Devices.

Heart rate variability (HRV) analysis is a useful method to assess abnormal functioning in the autonomic nervous system and to predict cardiac events in patients with heart failure (HF). HRV measurements with heart rate monitors have been validated with an electrocardiograph in healthy subjects but not in patients with HF. We explored the reproducibility of HRV in two consecutive six-minute walk tests (6MW), 60-minute apart, using a heart rate monitor (PolarS810i) and a portable electrocardiograph (called Holter) in 50 HF patients (mean age 59 years, NYHA II, left ventricular ejection fraction ~35%). The reproducibility for each device was analysed using a paired t-test or the Wilcoxon signed-rank test. Additionally, we assessed the agreement between the two devices based on the HRV indices at rest, during the 6MW and during recovery using concordance correlation coefficients (CCC), 95% confidence intervals and Bland-Altman plots. The test-retest for the HRV analyses was reproducible using Holter and PolarS810i at rest but not during recovery. In the second 6MW, patients showed significant increases in rMSSD and walking distance. The PolarS810i measurements had remarkably high concordance correlation [0.86

Reproducibility for heart rate variability analysis during 6-Min walk test in patients with heart failure and agreement between devices

Heart rate variability (HRV) analysis is a useful method to assess abnormal functioning in the autonomic nervous system and to predict cardiac events in patients with heart failure (HF). HRV measurements with heart rate monitors have been validated with an electrocardiograph in healthy subjects but not in patients with HF. We explored the reproducibility of HRV in two consecutive six-minute walk tests (6MW), 60-minute apart, using a heart rate monitor (PolarS810i) and a portable electrocardiograph (called Holter) in 50 HF patients (mean age 59 years, NYHA II, left ventricular ejection fraction ~35%). The reproducibility for each device was analysed using a paired t-test or the Wilcoxon signed-rank test. Additionally, we assessed the agreement between the two devices based on the HRV indices at rest, during the 6MW and during recovery using concordance correlation coefficients (CCC), 95% confidence intervals and Bland-Altman plots. The test-retest for the HRV analyses was reproducible using Holter and PolarS810i at rest but not during recovery. In the second 6MW, patients showed significant increases in rMSSD and walking distance. The PolarS810i measurements had remarkably high concordance correlation [0.86

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.

Efeitos de um programa combinado de treinamento muscular inspiratório e de fortalecimento muscular periférico na capacidade respiratória, na capacidade funcional e na qualidade de vida de indivíduos com insuficiência cardíaca avançada / Effects of combined inspiratory and resistance training programs on the respiratory capacity, functional capacity and quality of life in patients with chronic heart failure

Introdução: A insuficiência cardíaca (IC) é uma síndrome multissistêmica via final comum de diversas doenças cardíacas que cursa com redução da capacidade funcional e sintomas como fadiga muscular, dispneia e piora na qualidade de vida. Para melhorar a capacidade respiratória e funcional desses pacientes, estratégias voltadas ao fortalecimento muscular podem ser utilizadas, tais como o treinamento muscular inspiratório e o fortalecimento muscular periférico. Objetivo: Avaliar os efeitos de um programa de treinamento combinado muscular inspiratório e periférico de baixa intensidade (TBI) e de moderada intensidade (TMI) sobre a força muscular respiratória, a capacidade funcional e a qualidade de vida de pacientes com IC avançada. Métodos: Cinquenta e três pacientes com idade >= 18 anos, New York Heart Association (NYHA) classe funcional II-III e fração de ejeção do ventrículo esquerdo < 40% foram randomizados em grupo Controle (sem intervenção), TBI (15% da pressão inspiratória máxima e 0,5 kg de carga periférica) ou TMI (30% da pressão inspiratória máxima e 50% da 1 repetição máxima). Ambos os programas de treinamento foram aplicados ao longo de 8-semanas e 7 sessões/semana com duração de 45 minutos cada sessão. Nós avaliamos ao longo do estudo: qualidade de vida, força muscular respiratória, função pulmonar, inflamação de vias aéreas, força muscular periférica, distância percorrida e classificação funcional NYHA. Resultados: Após 8-semanas, todos os pacientes dos grupos Controle (n=9), TBI (n=13) e TMI (n=13) relataram melhora de 10% na qualidade de vida. Os programas TBI e TMI resultaram em melhora da força muscular inspiratória (24 e 33%, respectivamente), força muscular periférica de membros superiores (41 e 72%, respectivamente) e de membros inferiores (28 e 47%, respectivamente) além de aumentar a distância percorrida (9 e 16%, respectivamente). O TMI também levou à melhora da força muscular expiratória e a melhora da classe funcional NYHA. Conclusões: O...

Introduction: Heart failure (HF) is a multisystem syndrome and a final common pathway of several cardiovascular diseases that results in reduction of the functional capacity and symptoms such as early fatigue, dyspnea and reduction in quality of life. To improve the respiratory and functional capacity of these patients, strategies such as peripheral muscle strengthening and inspiratory muscle strengthening can be used. Objective: To assess the effects of a combined inspiratory and resistance training at low intensity (LRT) and moderate intensity (MRT) on the respiratory muscle strength, functional capacity and quality of life in patients with HF. Methods: Fifty-three patients aged >= 18 years, New York Heart Association (NYHA) functional class II-III and left ventricular ejection fraction < 40% were randomly assigned to a control group (non-exercise), the LRT group (15% maximal inspiratory workload and 0.5 kg of peripheral muscle workload) or the MRT group (30% maximal inspiratory workload and 50% of 1 maximum repetition peripheral muscle workload). Both training programs were performed along 8-weeks and 7 sections/week with 45 min each exercise section. We assessed quality of life using questionnaires, respiratory muscle strength, pulmonary function, airway inflammation, peripheral muscle strength, walking distance and NYHA functional class along the study period. Results: After 8- weeks, all patients from Control (n=9), LRT (n=13) and MRT (n=13) reported 10% improvement in quality of life. LRT and MRT resulted in respiratory muscle improvement (24 and 33%, respectively) and peripheral muscle strength in upper limbs (41 and 72%, respectively) and in lower limbs (28 and 47%, respectively), besides improvement in walking distance (9 and 16%, respectively). The MRT also improved expiratory muscle strength and NYHA functional class. Conclusions: The MRT improved inspiratory, expiratory and peripheral muscle strength, walking distance and NYHA...

Randomized and comparative study between two intra-hospital exercise programs for heart transplant patients.

OBJECTIVE: To compare the effects of two physical therapy exercise in-hospital programs in pulmonary function and functional capacity of patients in the postoperative period of heart transplantation. METHODS: Twenty-two heart transplanted patients were randomized to the control group (CG, n=11) and training group (TG, n=11). The control group conducted the exercise program adopted as routine in the institution and the training group has had a protocol consisting of 10 stages, with incremental exercises: breathing exercises, resistance training, stretching and walking. The programs began on the first day after extubation and stretched until hospital discharge. Assessed pulmonary function, distance walked in six minutes walk test (6MWT) and peripheral muscle strength by one repetition maximum test (1RM). RESULTS: Similar behavior was observed between the two groups treated, with statistically significant increases between the first and second test of the following variables: FVC (59% in CG and 35.2% in TG); MIP (8.6% in CG and 53.5% in TG), MEP (28.8% in CG and 40.7% in TG) and 6MWT (44.5% in CG and 31.4% in TG). There was an increase of peripheral strength by 1RM test, over time, to the muscle groups of the elbow flexors, shoulder flexors, hip abductors and knee flexors. CONCLUSION: Heart transplant patients benefit from exercise programs in hospital, regardless of the program type applied. A new training proposal did not result in superiority compared to routine programme applied. Exercise protocols provided improves in ventilatory variables and functional capacity of this population.

Randomized and comparative study between two intra-hospital exercise programs for heart transplant patients / Estudo randomizado e comparativo entre dois programas de exercícios intra-hospitalares para pacientes de transplante de coração

OBJECTIVE: To compare the effects of two physical therapy exercise in-hospital programs in pulmonary function and functional capacity of patients in the postoperative period of heart transplantation. METHODS: Twenty-two heart transplanted patients were randomized to the control group (CG, n=11) and training group (TG, n=11). The control group conducted the exercise program adopted as routine in the institution and the training group has had a protocol consisting of 10 stages, with incremental exercises: breathing exercises, resistance training, stretching and walking. The programs began on the first day after extubation and stretched until hospital discharge. Assessed pulmonary function, distance walked in six minutes walk test (6MWT) and peripheral muscle strength by one repetition maximum test (1RM). RESULTS: Similar behavior was observed between the two groups treated, with statistically significant increases between the first and second test of the following variables: FVC (59% in CG and 35.2% in TG); MIP (8.6% in CG and 53.5% in TG), MEP (28.8% in CG and 40.7% in TG) and 6MWT (44.5% in CG and 31.4% in TG). There was an increase of peripheral strength by 1RM test, over time, to the muscle groups of the elbow flexors, shoulder flexors, hip abductors and knee flexors. CONCLUSION: Heart transplant patients benefit from exercise programs in hospital, regardless of the program type applied. A new training proposal did not result in superiority compared to routine programme applied. Exercise protocols provided improves in ventilatory variables and functional capacity of this population.

OBJETIVO: Comparar os efeitos de dois programas fisioterapêuticos de exercícios intra-hospitalares na função pulmonar e na capacidade funcional de pacientes no período pós-operatório de transplante cardíaco. MÉTODOS: Vinte e dois transplantados de coração foram randomizados em Grupo Controle (GC, n=11) e Grupo de Treinamento (GT, n=11). O GC realizou o programa de exercícios adotado como rotina na instituição e o GT realizou protocolo constituído de 10 fases, com exercícios incrementais: exercícios respiratórios, resistidos, alongamentos e caminhada. Os programas tiveram início no primeiro dia após a extubação e se estenderam até a alta hospitalar. Avaliou-se função pulmonar, distância percorrida no teste de caminhada dos seis minutos (TC6M) e força muscular periférica pelo teste de uma repetição máxima (1RM). RESULTADOS: Observou-se comportamento semelhante entre os dois grupos tratados, com aumentos estatisticamente significantes entre o primeiro e o segundo teste das variáveis: CVF (59% no GC; 35,2% no GT); PIMax (8,6% no GC; 53,5% no GT, PEMax (28,8% no GC; 40,7% no GT) e TC6M (44,5% no GC; 31,4% no GT). Houve aumento de força periférica pelo teste de 1RM para os músculos flexores de cotovelo, flexores de ombro, abdutores de quadril e flexores de joelho ao longo do tempo. CONCLUSÃO: Pacientes transplantados de coração se beneficiam da aplicação de programas de exercícios no período intra-hospitalar, independente do tipo de programa aplicado. Uma nova proposta de treinamento não resultou em superioridade em relação ao programa aplicado de rotina. Os protocolos de exercícios proporcionaram melhora das variáveis ventilatórias e da capacidade funcional dessa população.

Aplicabidade de um protocolo de interrupção da ventilação mecânica em pacientes no pós-operatório de cirurgia cardíaca

A cirurgia cardíaca tem sido o tratamento de escolha para diminuir a morbilidade de paciente com doenças diovarculares. Os anestésicos usados durante o ato cirúrgico deprimem o centro respiratório, impossibilitando a respitação espontânea. A autonomia respiratória desses pacientes retorna tão logo cesse o efeito anestésico, dando condições de rápida extubação. O objetivo do presente estudo foi avaliar a eficácia de um protocolo de interrupção da ventilação mecãnica em pacientes nos pós-operatório de cirurgia cardíaca do Instituto Dante Pazzanese de Cardiologia, para posteriormente discutir sua aplicabilidade e segurança. Participaram do estudo 175 pacientes num período de quatro meses, tendo como critério de inclusão a realização de cirurgia cardíaca sob assistência ventilatória mecânica, idade maior que 15 anos e intubação endotraqueal menor que 24 horas. O sucesso do protocolo consistia em autonomia ventilatória até 24 horas após a extubação. Dos 175 pacientes, 27 foram excluídos do trabalho, 107 foram extubados pelo protocolo e 41 tiveram que suspender o estudo por complicações respiratórias ou hemodinâmicas. Daqueles que concluíram o estudo, nenhum necessitou de reintubação, sendo o sucesso considerado de 100%. A PaCO2 e a pressão arterial média nos pacientes que falharam apresentaram diferença estatisticamente significante quando comparados aos pacientes do grupo sucesso. Conclui-se que a extubação rápida em pacientes no pós-operatório de cirurgia cardíaca foi segura e o protocolo foi eficaz para esse tipo de população.