CPET in Evaluation of PH in COPD Patients

Study Overview
=================
Brief Summary
-----------------
To evaluate the entire course of exercise during CPET in COPD patients. To study whether CPET, PFTs and arterial blood gases could discriminate between COPD patients with and without PH. To study whether the existence of pulmonary hypertension in COPD is related to characteristic findings in gas exchange and circulatory parameters during cardiopulmonary exercise testing (CPET).

Detailed Description
-----------------
(COPD) is a common cause of pre-capillary pulmonary hypertension (PH). Pulmonary hypertension (PHT) is a common complication of COPD and is determinant for the prognosis of COPD. PHT is defined as A mean PAP of ≥ 25 mmHg measured by right heart catheterization at rest. Exercise tolerance in patients with COPD is reduced due to ventilatory limitation, gas exchange abnormalities, and deconditioning as the disease progresses, and this may impair functional capacity and the quality of life. COPD patients usually terminate physical activity when the ventilatory requirement exceeds their maximal ventilatory capacity. If they have PH, the altered hemodynamic response may reduce their exercise capacity further. Nowadays, despite the fact that LTOT improves the survival of hypoxaemic patients, PH is still associated with lower survival rates . Importantly, an elevated Ppa was also associated with an increased risk of severe acute exacerbation in COPD patients with moderate-to-severe airflow limitation . Impaired exercise tolerance in COPD patients would suggest that cardiopulmonary exercise test (CPET) is a valuable tool to reveal whether they have PH or not. Transthoracic echocardiography (TTE) is one such tool and is widely available and safe. In addition to its role in diagnosis, it can be used to screen for high-risk patient populations, to assess prognosis and to monitor disease stability and response to treatment.

Official Title
-----------------
Cardiopulmonary Exercise Test in Evaluation of Pulmonary Hypertension in COPD Patients

Conditions
-----------------
COPD, Pulmonary Hypertension Secondary

Intervention / Treatment
-----------------
* Diagnostic Test: Cardiopulmonary exercise test


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Stable COPD patients with age ≥ 40 years. Prior to inclusion, the COPD diagnosis was verified by spirometry before and after bronchodilation. treatment was optimized and Patients on regular medication. Exclusion Criteria: Patients who refuse to participate in the study. Patients underwent thorough pulmonary and cardiologic preinclusion screening, and those with pulmonary disease other than COPD and emphysema. arrhythmia valvular or coronary heart disease left ventricle dysfunction obstructive sleep apnea syndrome pulmonary embolism systemic hypertension ≥160/90 mmHg inflammatory disease hyperthyroidism renal failure inability to exercise (due to orthopedic, neurologic or musculoskeletal problem).

Ages Eligible for Study
-----------------
Minimum Age: 40 Years
Maximum Age: 80 Years

Sexes Eligible for Study
-----------------
All

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Intervention/Treatment |
| --- |
|Diagnostic Test: Cardiopulmonary exercise test|we prepared incremental treadmill exercise protocol in which the work rate increased at one-minute intervals.Transthoracic Echocardiography(TTE) : The first step non-invasive method to diagnose PHT.|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Measurement of oxygen uptake during cardiopulmonary exercise testing (% predicted) | For the assessment whether the existence of pulmonary hypertension in COPD is related to characteristic findings during cardiopulmonary exercise testing (CPET). | Baseline | 
| Measurement the arterial pO2 in mmHg and arterial pCO2 at baseline | The blood gases pO2 and pCO2 are taken to characterize the gas exchange during cardiopulmonary exercise which is a routine procedure | Baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| measurement of symptoms quantified by COPD Assessment Test (CAT Assessment)- total score 40. | For the assessment of the symptoms of the study group and its relation to exercise capacity and the impact COPD on wellbeing and daily life - CAT score < 10 is associated with better outcome and prognosis but score = or > 10 is associated with poor outcome and prognosis. | Baseline | 
| measurement of dyspnoea quantified by the modified Medical Research Council (mMRC) Dyspnea Scale (grades from 0 to 4 ) | measures perceived respiratory disability indicating the extent to which their breathlessness affects their mobility - dyspnoea is assessed by accepted questionnaires typically used for COPD patients at baseline- grade <2 indicates better outcome and prognosis but grade = or >2 indicates poor outcome and prognosis. | Baseline | 
| Measurement of FEV1 | For assessment of which degrees of severity of COPD are more related to development of COPD with pulmonary hypertension. | Baseline | 
| Measurement of Breathing reserve during cardiopulmonary exercise testing | The breathing reserve in % is assessed at the end of the cardiopulmonary exercise testing to characterize a ventilatory limitation of the exercise test. It is calculated as percent from the minute ventilation in relation to the maximum mandatory ventilation. The measurement is a routine measurement during cardiopulmonary exercise testing. | Baseline | 
| Measurement of Oxygen pulse during cardiopulmonary exercise testing |  | Baseline | 
| Presence of cardiovascular comorbidities | For the cardiopulmonary characterization clinical characteristics, lung function, blood gases, laboratory investigation, ECG and echocardiography were used in addition to cardiopulmonary exercise testing. | Baseline |