HRCT was used to evaluate pulmonary vascular remodeling in COPD. The role of H2S in pulmonary vascular remodeling in COPD was analyzed, in order to provide a basis for seeking new therapeutic targets.

This study aimed to investigate the relationship between endogenous H2S and pulmonary vascular remodeling on HRCT in patients with COPD through the determination of H2S and its synthase mRNA levels in blood and pulmonary vessels by HRCT, to evaluate the role of H2S in pulmonary vascular remodeling in COPD and to provide a basis for seeking new therapeutic targets. This study had predictive value for clinical prognosis of patients. It had important clinical guiding significance and social and economic benefit to comprehensively understand the pathogenesis of COPD.

Inclusion Criteria:

• Patients meet the GOLD 2016 guidelines for diagnostic criteria of COPD: dyspnea, chronic cough and/or sputum symptoms, exposure to risk factors, and pulmonary function after inhalation of bronchodilator with forced expiratory volume (FEV1)/forced vital capacity (FVC) < 70%.

Exclusion Criteria:

- 1. Other lung diseases such as pneumonia, lung cancer, tuberculosis, pulmonary embolism, heart diseases such as heart failure, ventricular septal defect, patent ductus arteriosus, thoracic deformity and pleural diseases.

2. Patients who are unable to understand and/or complete questionnaire.

Outpatient with stable chronic obstructive pulmonary disease