The evaluation of right ventricular function is clinically useful in patients with COPD because the presence of right ventricular failure has prognostic implications. Our purpose was: 1)to compare tissue Doppler imaging, TDI, and the recently developed strain rate, SR, imaging technique parameters with conventional indices evaluating right ventricular function; 2)to assess the correlation among TDI/SR parameters and respiratory function tests.
Twenty-nine patients with COPD were included in the study. 15 patients had pulmonary artery pressure >35mmHg (group I), 14 patients had pulmonary artery pressure <35mmHg (group II). Sixteen age- and gender-matched healthy subjects who had normal cardiac findings served as controls (group III). Right ventricular ejection fraction (EF), fractional shortening (FS), and tricuspid flow filling parameters (E/A ratio, DT) were determined. Offline analysis of the myocardial velocity data sets was performed using dedicated software (Aplio, Toshiba Corp.). Velocity and strain traces from right ventricular free wall at 3 levels (basal, mid cavity, and apical) were processed simultaneously in the same cineloop in the apical 4-chamber view. Diastolic TDI values (Ew, Aw), peak systolic strain and systolic and diastolic strain rate values were determined. Echocardiographic parameters were evaluated after the respiratory function tests were performed:FEV1;FEV1/VC;DLCO;DLCO/VA.
Ew/Aw ratio at apical and mid level was lower in Group I and II than in Group III:p<0.005.Peak systolic strain and systolic and diastolic strain rate at apical and mid level were lower in Group I and II than in Group III:p<0.001.Right ventricular EF,FS,E/A ratio, and DT were not different among the three groups. No correlation was found between EF, FS, E/A ratio, DT, and respiratory function tests. A highly significant relationship was shown between peak systolic strain at mid level and DLCO/VA:r=0.67, p<0.001 and peak systolic strain at mid level and FEV1/VC:r=0.69,p<0.001.
In COPD patients TDI/SR parameters can determine right ventricular dysfunction that is not shown by conventional echocardiographic indices and is correlated with respiratory function tests.
FEV1/VC,DLCO/VA,TDI and SR will assist clinicians in making more accurate assessments of their COPD patients’ disease status.
C. Terzano, None.