Evaluation of Right Ventricular Function in Patients With COPD

Abstract

Pulmonary hypertension is an independent risk factor for death in patients with COPD. Current prognostic models of COPD do not include sufficient indicators of right ventricular (RV) function to enable accurate assessment of changes in RV function over time. The aim of the present study was to test the hypothesis that it would be useful to include noninvasive markers of RV function in the routine assessment and prognostic models of early stage COPD with or without pulmonary hypertension. We reviewed the clinical records of 49 male subjects who had COPD but no other conditions that might affect physical status or prognosis, who underwent cardiac ultrasonography. Various echocardiographic parameters of pulmonary circulation and RV function were compared with indices of physical status and prognosis. The Medical Research Council dyspnea score was higher in subjects with echocardiographic findings suggestive of pulmonary hypertension than those without (mean ± SD 3.17 ± 1.23 vs 2.26 ± 0.81, P = .02). RV ejection time, RV isovolumetric relaxation time, RV isovolumetric contraction time + RV isovolumetric relaxation time, and RV total ejection isovolume index differed significantly between subjects with echocardiographic findings suggestive of pulmonary hypertension and those without. The RV total ejection isovolume index was strongly correlated with the MRC score (P < .001), and was significantly correlated with the overall survival rate (hazard ratio 5.31, 95% CI 1.91-14.77) and hospital-free survival rate (hazard ratio 3.26, 95% CI 1.48-7.16). It may be valuable to add assessment of RV function to the routine evaluation of physical status in patients with COPD.