PURPOSE: In patients with chronic obstructive pulmonary disease (COPD), left ventricular (LV) systolic dysfunction and structural changes are known to be rare, while right ventricular (RV) dysfunction and structural alteration and/or LV diastolic dysfunction are common. We evaluated cardiac structure and function in COPD patients by using echocardiography.
METHODS: Echocardiographic examinations were performed in 69 patients with clinically stable COPD and without history of heart disease, and 23 control subjects with normal lung function. Echocardiographic parameters of COPD patients were compared with those of controls, and assessed according to COPD stage by using the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria.
RESULTS: COPD patients had significantly lower body weight (p=0.002), and higher pack-years of smoking (p<0.001) and heart rate than controls (p=0.046). Echocardiogram showed that LV end diastolic diameter (p<0.001), LV end systolic diameter (p=0.032), left atrial (LA) diameter (p=0.020), and LV mass in COPD patients were significantly decreased as compared with controls (p=0.006). However, there was no difference between COPD patients and controls in the following parameters reflecting LV diastolic function; mitral flow velocity in early and late diastole E/A ratio, deceleration time, early diastole velocity of mitral annulus E’ measured by tissue Doppler echocardiography and E/E’ ratio. Mean RV systolic pressure (RVSP) of COPD patients was not significantly higher than controls. According to COPD stage, body weight (p<0.001), body mass index (BMI) (p<0.001), and LV mass were significantly different (p=0.011). Although patients with stage IV showed higher mean RVSP and more frequent pulmonary hypertension than patients with I, II, and III, they are not statistically significant. In COPD patients, LV mass (r=0.432) (p<0.001) and BMI significantly correlated with FEV1 % predicted (r=0.600) (p<0.001).
CONCLUSION: COPD patients showed lower LV mass and LA and LV diameters than controls, even though both groups had normal LV functions. In particular, LV mass was positively related to FEV1 in COPD.
CLINICAL IMPLICATIONS: LV mass appears to correlate with lung function. Further investigations focusing on its clinical significance are needed.
DISCLOSURE: Yunsu Sim, No Financial Disclosure Information; No Product/Research Disclosure Information