The Effect of Pulmonary Hypertension on Aerobic Exercise Capacity in Lung Transplant Candidates with Advanced Emphysema

Effect of pulmonary hypertension on exercise tolerance in patients with COPD: a prognostic systematic review and meta-analysis

Background

Pulmonary hypertension (PH) is a frequent complication in patients with COPD.

Objective

To determine if, in patients with COPD, the presence of PH decreases exercise tolerance.

Methods

We included studies that analysed exercise tolerance using a cardiopulmonary exercise test (CPET) in patients with COPD with PH (COPD-PH) and without PH (COPD-nonPH). Two independent reviewers analysed the studies, extracted the data and assessed the quality of the evidence.

Results

Of the 4915 articles initially identified, seven reported 257 patients with COPD-PH and 404 patients with COPD-nonPH. The COPD-PH group showed differences in peak oxygen consumption (V′_O2peak), −3.09 mL·kg⁻¹·min⁻¹ (95% CI −4.74 to −1.43, p=0.0003); maximum workload (W_max), −20.5 W (95% CI −34.4 to −6.5, p=0.004); and oxygen pulse (O₂ pulse), −1.24 mL·beat⁻¹ (95% CI −2.40 to −0.09, p=0.03), in comparison to the group with COPD-nonPH. If we excluded studies with lung transplant candidates, the sensitivity analyses showed even bigger differences: V′_O2, −4.26 mL·min⁻¹·kg⁻¹ (95% CI −5.50 to −3.02 mL·kg⁻¹·min⁻¹, p<0.00001); W_max, −26.6 W (95% CI −32.1 to −21.1 W, p<0.00001); and O₂ pulse, −2.04 mL·beat⁻¹ (95% CI −2.92 to −1.15 mL·beat⁻¹, p<0.0001).

Conclusion

Exercise tolerance was significantly lower in patients with COPD-PH than in patients with COPD-nonPH, particularly in nontransplant candidates.

The V′_O2peak, Wmax and O₂ pulse values were significantly lower in patients with COPD-PH than in patients with COPD-nonPH, particularly in nontransplant candidateshttps://bit.ly/3s5dtJ9

Diagnostic Validity of Cardiopulmonary Exercise Testing for Screening Pulmonary Hypertension in Patients With Chronic Obstructive Pulmonary Disease

PURPOSE

To determine diagnostic validity of cardiopulmonary exercise testing (CPX) parameters for detecting pulmonary hypertension (PH) in patients with chronic obstructive pulmonary disease (COPD) and to investigate association between CPX parameters and indices of PH.

METHODS

This cross-sectional study enrolled 48 moderate to very severe COPD patients in whom PH was confirmed by echocardiography. Symptom-limited CPX was performed using an incremental exercise protocol. Relevant CPX parameters were derived and were tested for their diagnostic ability for diagnosing PH. Logistic regression was applied to examine the effect of various clinical covariates on the diagnostic ability of exercise test variables for detecting PH.

RESULTS

Of the 48 patients, 29 were diagnosed with PH and 19 were negative for PH based on echocardiographic testing. CPX measures including peak oxygen uptake (% predicted (Equation is included in full-text article.)O2peak, (Equation is included in full-text article.)O2peak [mL/min], (Equation is included in full-text article.)O2/kg), oxygen pulse ((Equation is included in full-text article.)O2/HR % predicted, (Equation is included in full-text article.)O2/HR mL/beat), and peak minute ventilation ((Equation is included in full-text article.)Epeak [L/m]) were inversely correlated with mean pulmonary arterial pressure (mPAP). Peak (Equation is included in full-text article.)O2/HR and (Equation is included in full-text article.)O2peak were found to be significant predictors of PH in univariate analysis. (Equation is included in full-text article.)O2peak (%), (Equation is included in full-text article.)O2/HR (mL/beat), and desaturation (%) were identified as independent predictors of PH adjusted for age, forced expiratory volume in 1 sec (%), and forced vital capacity (L).

CONCLUSION

The present study validates the use of CPX parameters such as (Equation is included in full-text article.)O2peak and (Equation is included in full-text article.)O2/HR as a diagnostic tool for correctly identifying PH in COPD patients. Therefore, CPX may be used as an adjunct to echocardiographic measurement of PH where there is unavailability of equipment and expertise.

Effects of Pulmonary Hypertension on Exercise Capacity in Patients With Chronic Obstructive Pulmonary Disease

INTRODUCTION

The impact of pulmonary hypertension (PH) on exercise tolerance in chronic obstructive pulmonary disease (COPD) has not been fully elucidated. It is necessary to characterize pulmonary hemodynamics in patients with moderate to severe COPD in order to improve their management. The aim of the study was to determine whether in COPD the presence of PH is associated with reduced exercise tolerance in a cohort of stable COPD patients.

METHODS

Cross-sectional analysis of 174 COPD patients clinically stable: 109 without PH and 65 with PH (COPD-PH). We assessed socio-demographic data, lung function, quality of life, dyspnea, cardiopulmonary exercise testing (CPET), constant workload endurance time (CWET), and six-minute walk test (6MWT). We elaborated a logistic regression model to explore the impact of PH on exercise capacity in COPD patients.

RESULTS

COPD-PH patients showed lower exercise capacity both at maximal (CPET) (43(20) versus 68(27) Watts and 50(19)% versus 71(18)% predicted peak oxygen consumption (VO₂peak), COPD-PH and COPD, respectively), and at submaximal tests (6MWT) (382(94) versus 486(95) m). In addition, the COPD-PH group had lower endurance time than the non-PH COPD group (265(113) s and 295(164) s, respectively).

CONCLUSIONS

The presence of PH is an independent factor that impairs exercise capacity in COPD.

Cardiopulmonary exercise test and PaO2 in evaluation of pulmonary hypertension in COPD

Background

Exercise tolerance decreases as COPD progresses. Pulmonary hypertension (PH) is common in COPD and may reduce performance further. COPD patients with and without PH could potentially be identified by cardiopulmonary exercise test (CPET). However, results from previous studies are diverging, and a unified conclusion is missing. We hypothesized that CPET combined with arterial blood gases is useful to discriminate between COPD outpatients with and without PH.

Methods

In total, 93 COPD patients were prospectively included. Pulmonary function tests, right heart catheterization, and CPET with blood gases were performed. The patients were divided, by mean pulmonary artery pressure, into COPD-noPH (<25 mmHg) and COPD-PH (≥25 mmHg) groups. Linear mixed models (LMMs) were fitted to estimate differences when repeated measurements during the course of exercise were considered and adjusted for gender, age, and airway obstruction.

Results

Ventilatory and/or hypoxemic limitation was the dominant cause of exercise termination. In LMM analyses, significant differences between COPD-noPH and COPD-PH were observed for PaO₂, SaO₂, PaCO₂, ventilation, respiratory frequency, and heart rate. PaO₂ <61 mmHg (8.1 kPa) during unloaded pedaling, the only load level achieved by all the patients, predicted PH with a sensitivity of 86% and a specificity of 78%.

Conclusion

During CPET, low exercise performance and PaO₂ strongly indicated PH in COPD patients.

Accuracy of CT Pulmonary Artery Diameter for Pulmonary Hypertension in End-Stage COPD

Introduction

Pulmonary hypertension (PH) in COPD is associated with a higher mortality and an increased risk on exacerbations compared to COPD patients without PH. The aim was to evaluate the diagnostic value of pulmonary artery (PA) measurements on chest computed tomography (CT) for PH in end-stage COPD.

Methods

COPD patients evaluated for eligibility for lung transplantation between 2004 and 2015 were retrospectively analyzed. Clinical characteristics, chest CTs, spirometry, and right-sided heart catheterizations (RHC) were studied. Diameters of PA and ascending aorta (A) were measured on CT. Diagnostic properties of different cut-offs of PA diameter and PA:A ratio in diagnosing PH were calculated.

Results

Of 92 included COPD patients, 30 (32.6 %) had PH at RHC (meanPAP > 25 mm Hg). PA:A > 1 had a negative predictive value (NPV) of 77.9 % and a positive predictive value (PPV) of 63.1 % with an odds ratio (OR (CI 95 %)) of 5.60 (2.00–15.63). PA diameter ≥30 mm had a NPV of 78 % and PPV of 64 % with an OR (CI 95 %) of 6.95 (2.51–19.24).

Conclusion

A small PA diameter and PA:A make the presence of PH unlikely but cannot exclude its presence in end-stage COPD. A large PA diameter and PA:A maybe used to detect PH early.