Right heart changes depending on the functional status of patients with COPD combined with hypertension

Abstract

Background: The right heart (RH) is not as well understood as the left. Early identification of the RH overload will allow to carry out primary prevention of heart failure.

Purpose: to compare the RH echocardiographic (Echo) data with the functional status data of patients with COPD and hypertension (HT) - dyspnea, oxygen saturation (SpO₂) level before and after the 6-min walk test (6MWT), the distance walked in 6MWT (6MWD).

Methods: In total, 69 COPD patients (GOLD 2, group B) in remission with HT stage II 55,80±5,51 y.o. (57 m, 12 f) were monitored. All patients underwent the 6MWT, pulse oximetry, spirometry, chest X-ray, electrocardiography, echocardiography. Desaturation (DSat) was understood as declining SpO₂ during 6MWT ≥ 4% from baseline.

Results: We found significant (p<0,05) correlations: inverse – between the 6MWD and the right atrial (RA) size (r=-0,33), the right ventricle (RV) wall thickness (r=-0,25); direct – between the DSat and the RA size (r=0,27), the RV wall thickness (r=0,33). Dyspnea level (Borg Scale) didn’t show significant correlations with Echo data. To establish the prognostic significance of DSat on forming the RH overload features we divided patients into groups: 1st - with DSat, 2nd - without DSat. In the 1st group we found signs of overload of the RH chambers (p<0,05) – increasing the RA size (39,79±2,27 mm vs. 35,83±5,02 mm) and the RV wall thickness (5,58±0,57 mm vs. 5,22±0,61 mm), decreasing the RV diameter (27,10±2,22 mm vs. 28,37±2,40 mm). DSat was associated with RV pressure overload.

Conclusions: DSat and reduced exercise tolerance were associated with early Echo data of the RH overload, as opposed to dyspnea level.