Background: Data on cardiac alterations such as left ventricular (LV) hypertrophy, diastolic dysfunction, and lower stroke volume in patients with COPD are discordant. In this study, we investigated whether early structural and functional cardiac changes occur in patients with COPD devoid of manifest cardiovascular disease, and we assessed their associations with clinical and functional features.
Methods: Forty-nine patients with COPD belonging to all Global Initiative for Chronic Obstructive Lung Disease (GOLD) classes were enrolled and compared with 36 controls. All subjects underwent clinical history assessment, lung function testing, blood pressure measurement, electrocardiography, and conventional and Doppler tissue echocardiography. Patients were also subjected to computed tomography to quantify emphysema score.
Results: Patients with COPD had lower LV cavity associated with a marked increase in relative wall thickness (RWT), suggesting concentric remodeling without significant changes in LV mass. RWT was significantly associated with ratio of the forced expiratory volume in 1 second to the forced vital capacity and emphysema score and was the only cardiac parameter that - after multivariate analysis - significantly correlated with COPD conditions in all individuals. Receiver operating characteristic curve analysis showed that RWT (with a cutoff point of 0.42) predicted the severity of COPD with 83% specificity and 56% sensitivity (area under the curve =0.69, 95% confidence interval =0.59-0.81). Patients with COPD showed right ventricular to be functional but no structural changes.
Conclusion: Patients with COPD without evident cardiovascular disease exhibit significant changes in LV geometry, resulting in concentric remodeling. In all individuals, RWT was significantly and independently related to COPD. However, its prognostic role should be determined in future studies.
Keywords: COPD; Doppler tissue echocardiography; emphysema score; left ventricular function; left ventricular remodeling; right ventricular function.