To investigate the value of echocardiography in assessing the right heart function of patients with chronic obstructive pulmonary disease (COPD).

Forty-four COPD patients who were treated in Beijing Anzhen Hospital of Capital Medical University, from April 2016 to April 2017, were selected as COPD group; and 12 healthy physical examiners were included in healthy control group during the same period. Patients were divided into COPD with pulmonary hypertension (PH) group and COPD without PH group. All subjects were routinely examined by transthoracic echocardiography. The parameters of right heart function of all subjects were measured by echocardiography according to 2010 guideline of American Society of Echocardiography (ASE). Independent sample t test was used to compare echocardiographic routine parameters and recommended parameters of ASE guideline between COPD group and healthy control group. One-way analysis of variance was used to compare the routine parameters of echocardiography and the recommended parameters of the ASE guide in the patients of COPD with PH group and COPD without PH group and the healthy control group. SNK-q test was used for comparison between groups.

The right ventricle diameter (RVD) in group COPD was wider than that in healthy control group [(20.68±4.21) mm vs (18.17±1.75) mm], and the difference was statistically significant (t=2.92, P=0.005). There was no significant difference in the right ventricular outflow tract (RVOT), main pulmonary artery diameter (MPAD), left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD) and left ventricular ejection fraction (LVEF) between the COPD group and the healthy control group. Compared with the healthy control group, the diameter of right ventricle basal segment in the COPD group increased [(35.92±8.12) mm vs (27.75±3.17) mm], tricuspid annular plane systolic excursion (TAPSE) decreased [(19.61±4.08) mm vs (22.67±2.67) mm], right ventricular index of myocardial performance (RIMP) increased [(0.52±0.10) cm/s vs (0.43±0.04) cm/s)], and the differences were statistically significant (t=3.39, P=0.001; t=-2.44, P=0.019; t=4.31, P<0.001). There was no significant difference in right atrium area, E/A, E/E' and S' between COPD group and healthy control group. There was no significant difference in RVOT, RVD, MPAD, LVEDD, LVESD and LVEF in the patients of COPD with PH group and COPD without PH group and in the healthy control group. There was no significant difference in the right atrium area, E/A, E/E', TAPSE and S'. The right ventricular basal segment diameter and RIMP of COPD with PH group and COPD without PH group were higher than those of healthy control group [(37.99±9.66) mm, (34.47±6.70) mm vs (27.75±3.17) mm; (0.54±0.13) cm/s, (0.51±0.08) cm/s vs (0.43±0.04) cm/s]. The differences were statistically significant (q=6.960, 4.905, 5.796, 4.348, all P<0.05). However, there was no significant difference in right ventricular basal segment diameter and RIMP between COPD with PH group and COPD without PH group. The RVWT of COPD with PH group was higher than that of COPD without PH group [(5.29±0.69) mm vs (4.54±0.70) mm], and the difference was statistically significant (t=3.313, P=0.002).

The method recommended in the ASE guidelines for this study was more sensitive than conventional methods for the detection of changes in the structure of the right heart. The change of the right ventricular structure was the first manifestation of right heart involvement in COPD patients, and then the systolic function of the right ventricle diminished. The long-term effect of pulmonary hypertension was thickening of the right ventricular wall at the early stage and then enlargement of the right ventricle.