Echocardiography evaluation of right ventricular structure and function in patients with chronic obstructive pulmonary disease

Background Early and accurate assessment of right ventricular changes in patients with Chronic obstructive pulmonary disease(COPD)is of great value,because these changes are important factors affecting the prognosis of patients with COPD. This study aimed to investigate the changes of right ventricular structure and function by electrocardiography in COPD patients,and to evaluate the correlations of pulmonary function,COPD assessment test(CAT)score with the changes. Methods According to the"ABCD"2016 Global initiative for chronic obstructive pulmonary disease(GOLD)update,stable COPD patients were divided into four groups:GOLD A group,GOLD B group,GOLD C group,and GOLD D group. There were 30 patients of each group enrolled from December 2016 to December 2017 in Guangdong General Hospital. During the same period,30 physical examination volunteers were enrolled as the healthy control group. Pulmonary function and echocardiography were performed in all subjects. All COPD patients completed CAT test. One-way ANOVA and SNK-q test were used to analyze the differences in parameters of right ventricular structure and function between different GOLD groups and healthy controls. Pearson correlation analysis was used to analyze the relation between CAT score,forced expiratory volume in one second(FEV1)and echocardiographic parameters. Results Compared with control group,right ventricular wall thickness(RVWT)was significantly thicker in patients of GOLD A,B and C groups(P<0.001),but not for GOLD D group. In sharp contrast,only in the patients of GOLD D group,right ventricular basal diameter(RV basal diameter)and right ventricular outflow tract(RVOT)(2.84±0.56 cm and 4.63±0.54 cm)were significantly longer than those in healthy controls and other GOLD groups(P<0.001).The patients of GOLD C and D groups had higher E/A ratio and E/e′ ratio compared with control group,GOLD A and B groups(P<0.001). But only in GOLD D group,the fractional area change(FAC)and tricuspid annular plane systolic excursion(TAPSE)were decreased significantly,compared with control group and other GOLD groups(P<0.001). The right ventricular index of myocardial performance(RIMP)in GOLD B,C and D groups was increased significantly compared with healthy control and GOLD A group(P<0.001). Moreover,correlation analysis showed that no correlations were found between FEV1 and all parameters of right ventricular structure and function,but CAT was positively correlated with RIMP(r=0.696,P=0.019). Conclusions Echocardiography could be a good assessment for right ventricular structure and function in COPD patients. Right ventricular wall thickening and diastolic dysfunction occur in the early stage of COPD,followed by right ventricular volume enlargement and systolic dysfunction.