Non-invasive ventilatory support accelerates the oxygen uptake and heart rate kinetics and improves muscle oxygenation dynamics in COPD-HF patients.

BACKGROUND: The aim of this study was to explore the effects of non-invasive positive pressure ventilation (NIPPV) associated with high-intensity exercise on heart rate (HR) and oxygen uptake (V̇O2) recovery kinetics in in patients with coexistence of chronic obstructive pulmonary disease (COPD) and heart failure (HF). METHODS: This is a randomized, double blinded, sham-controlled study involving 14 HF-COPD patients, who underwent a lung function test and Doppler echocardiography. On two different days, patients performed incremental cardiopulmonary exercise testing (CPET) and two constant-work rate tests (80% of CPET peak) receiving Sham or NIPPV (bilevel mode - Astral 150) in a random order until the limit of tolerance (Tlim). During exercise, oxyhemoglobin and deoxyhemoglobin were assessed using near-infrared spectroscopy (Oxymon, Artinis Medical Systems, Einsteinweg, Netherland). RESULTS: The kinetic variables of both V̇O2 and HR during the high-intensity constant workload protocol were significantly faster in the NIPPV protocol compared to Sham ventilation (P < 0.05). Also, there was a marked improvement in oxygenation and lower deoxygenation of both peripheral and respiratory musculature in TLim during NIPPV when contrasted with Sham ventilation. CONCLUSIONS: NIPPV applied during high-intensity dynamic exercise can effectively improve exercise tolerance, accelerate HR and V̇O2 kinetics, improve respiratory and peripheral muscle oxygenation in COPD-HF patients. These beneficial results from the effects of NIPPV may provide evidence and a basis for high-intensity physical training for these patients in cardiopulmonary rehabilitation programs.

Effect of high-intensity exercise on cerebral, respiratory and peripheral muscle oxygenation of HF and COPD-HF patients.

OBJECTIVE: To investigate cerebral oxygenation (Cox) responses as well as respiratory (Res) and active peripheral muscle (Pm) O2 delivery during high-intensity cycling exercise and contrast responses between patients with coexistent chronic obstructive pulmonary disease (COPD)-heart failure (HF) and HF alone. METHODS: Cross-sectional study involving 11 COPD-HF and 11 HF patients. On two different days, patients performed maximal incremental cardiopulmonary exercise testing (CPET) and constant load exercise on a cycle ergometer until the limit of tolerance (Tlim). The high-intensity exercise session was 80% of the peak CPET work rate. Relative blood concentrations of oxyhemoglobin ([O2Hb]), deoxyhemoglobin ([HHb]) of Res, Pm (right vastus lateralis) and Cox (pre-frontal) were measured using near infrared spectroscopy. RESULTS: We observed a greater decrease in [O2Hb] at a lower Tlim in COPD-HF when compared to HF (P < 0.05). [HHb] of Res was higher (P < 0.05) and Tlim was lower in COPD-HF vs. HF. Pm and Cox were lower and Tlim was higher in (P < 0.05) HF vs. COPD-HF. In HF, there was a lower ∆[O2Hb] and higher ∆ [HHb] of Pm when contrasted to Cox observed during exercise, as well as a lower ∆ [O2Hb] and higher ∆ [HHb] of Res when contrasted with Cox (P < 0.05). However, COPD-HF patients presented with a higher ∆ [HHb] of Res and Pm when contrasted with Cox (P < 0.05). CONCLUSION: The coexistence of COPD in patients with HF produces negative effects on Cox, greater deoxygenation of the respiratory and peripheral muscles and higher exertional dyspnea, which may help to explain an even lower exercise tolerance in this multimorbidity phenotype.

Association Between the Predictors of Functional Capacity and Heart Rate Off-Kinetics in Patients with Chronic Obstructive Pulmonary Disease.

Background: The heart rate (HR) kinetics as well as other predictors of functional capacity such as the Chronic Obstructive Pulmonary Disease (COPD) Assessment Test (CAT), the Duke Activity Status Index (DASI) and the handgrip strength (HGS) represent important tools in assessing the impact of COPD on exercise performance and health status of individuals with COPD. Purpose: To verify the relationship between functional capacity, measured using the six-minute walking test (6MWT), with the HR off-kinetics, HGS and the DASI and CAT scores. Methods: For this cross-sectional study, 29 subjects with COPD underwent body composition, pulmonary function and cardiac function tests. Subsequently, the DASI and CAT questionnaires and HGS test were performed. The beat-to-beat R-R intervals (IRR) were collected in rest, during the test and in recovery after the 6MWT. The HR off-kinetics was obtained during a 360-second period in post-exercise recovery through the HR mono-exponential decay. Results: Moderate correlations were observed between: 1) walked distance (WD) in the 6MWT and the CAT and DASI scores (r= -0.58, p=0.001 and r= 0.58, p=0.001, respectively); 2) WD and HGS (r=0.37, p=0.05); 3) and WD and HR off-kinetics (τ; r= -0.54, p=0.002 and MRT; r= -0.55, p=0.002, respectively). Conclusion: The 6MWT performance is a direct measurement to evaluate functional capacity. Additionally, it is related to other direct and indirect markers for functional evaluation in patients with COPD. These results suggest the application of these tools in clinical practice, based on the accessibility, non-invasive character and easy applicability of these methods.

Left Ventricular Geometry in COPD Patients: ARE THERE ASSOCIATIONS WITH AIRFLOW LIMITATION, FUNCTIONAL CAPACITY, AND GRIP STRENGTH?

PURPOSE: Chronic obstructive pulmonary disease (COPD) and abnormalities of left ventricular (LV) geometry often coexist. This study aimed to verify whether LV geometry is associated with airflow obstruction, functional capacity, and grip strength in COPD patients. METHODS: Thirty-seven COPD patients (GOLD II, III, and IV) were allocated to three groups according to LV geometry as assessed by transthoracic echocardiography: normal (n = 13), concentric LV remodeling (n = 8), and concentric LV hypertrophy (LVH) (n = 16). Lung function was assessed using spirometry. The Duke Activity Status Index (DASI) was used to estimate functional capacity, and grip strength measurement was performed using a hydraulic hand dynamometer. RESULTS: The concentric LVH group presented lower DASI scores (P = .045) and grip strength (P = .006) when compared with the normal group. Correlations analysis showed the following: relative wall thickness negatively correlated with forced expiratory volume in the first second (r = -0.380; P = .025) and DASI score (r = -0.387, P = .018); LV mass index negatively correlated with grip strength (r = -0.363, P = .038). CONCLUSIONS: In COPD patients, LV geometry is associated with airflow limitation, functional capacity, and grip strength. Specifically, concentric LV remodeling is associated with increased airflow limitation and decreased functional capacity whereas increased LV mass is associated with decreased grip strength.

Validity, intra and inter-reliability of manual evaluation of the respiratory muscle strength in asthmatic patients.

OBJECTIVE: This study investigated the concurrent validity, inter and intra-reliability of manual evaluation in Asthma patients. METHODS: Twenty six asthma patients were assessed. Maximal respiratory muscle strength (Mrms) was tested by inspiratory and expiratory pressure (MIP and MEP, respectively) trough manovacuometer. In addition, Mrms of diaphragm (anterior and posterior), Intercostals (lower and upper portion) and Rectus abdominal were obtained manually, according to Medical Research Council (MRC) scale. Two independents evaluators, previously trained, made both measurements. RESULTS: Reproducibility of Mrms intra-evaluators: anterior diaphragm (ICCs, 0.79 and 0.67); Posterior portion of the diaphragm (ICCs, 0.43 and 0.51); Upper intercostals (ICCs, 0.47 and 0.40); Lower intercostals (ICCs, 0.81 and 0.51) and rectus abdominal (ICCs, 1.0). Inter-reproducibility of anterior diaphragm was low to moderate, while intercostals (upper and lower portion) was relatively low. However, rectus abdominal presented high reproducibility reflecting in almost perfect agreement. In addition, we found positive correlations between MIP versus Lower Intercostals (r = .60, p = .007) and MEP versus rectus abdominal (r = .41, p = .04). CONCLUSION: In asthmatic patients, manual evaluation of the respiratory muscles is reliable. In addition, maximal respiratory pressures using manometer assessment were related to manual evaluation, in special to diaphragm and rectus abdominal muscles.

Publisher Correction: The Value of Cardiopulmonary Exercise Testing in Determining Severity in Patients with both Systolic Heart Failure and COPD.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

The Value of Cardiopulmonary Exercise Testing in Determining Severity in Patients with both Systolic Heart Failure and COPD.

Our aim was to identify optimal cardiopulmonary exercise testing (CPET) threshold values that distinguish disease severity progression in patients with co-existing systolic heart failure (HF) and chronic obstructive pulmonary disease (COPD), and to evaluate the impact of the cut-off determined on the prognosis of hospitalizations. We evaluated 40 patients (30 men and 10 woman) with HF and COPD through pulmonary function testing, doppler echocardiography and maximal incremental CPET on a cycle ergometer. Several significant CPET threshold values were identified in detecting a forced expiratory volume in 1 second (FEV1) < 1.6 L: 1) oxygen uptake efficiency slope (OUES) < 1.3; and 2) circulatory power (CP) < 2383 mmHg.mlO2.kg-1. CPET significant threshold values in identifying a left ventricular ejection fraction (LVEF) < 39% were: 1) OUES: < 1.3; 2) CP < 2116 mmHg.mlO2.kg-1.min-1 and minute ventilation/carbon dioxide production (V̇E/V̇CO2) slope>38. The 15 (38%) patients hospitalized during follow-up (8 ± 2 months). In the hospitalizations analysis, LVEF < 39% and FEV1 < 1.6, OUES < 1.3, CP < 2116 mmHg.mlO2.kg-1.min-1 and V̇E/V̇CO2 > 38 were a strong risk predictor for hospitalization (P ≤ 0.050). The CPET response effectively identified worsening disease severity in patients with a HF-COPD phenotype. LVEF, FEV1, CP, OUES, and the V̇E/V̇CO2 slope may be particularly useful in the clinical assessment and strong risk predictor for hospitalization.