Quantitative evaluation of chronic pulmonary thromboemboli by multislice CT compared with pulsed Tissue Doppler Imaging and its relationship with brain natriuretic peptide

Abstract Purpose Chronic pulmonary arterial thromboembolism (CPATE) often causes right ventricular (RV) pressure overload but the relationship between the degrees of CPATE and RV pressure overload is not clear. To quantify the degrees of CPATE and RV pressure overload, we performed multislice computed tomography (CT) and Tissue Doppler Imaging (TDI) and compared the two modalities. Materials and methods Sixteen consecutive subjects (4 men, 12 women; age 27–72 with proven CPATE underwent CT. The right vascular obstruction index (VOI), the left VOI, and the total VOI (TVOI) were determined using the scoring system of Qanadli. The early systolic myocardial velocity (Sw) and diastole myocardial velocity (Ew) at the tricuspid annulus and the early diastolic tricuspid inflow ( E ) were obtained by TDI in the apical four chamber view; RV systolic pressure (RVSP) was estimated by pressure gradient of tricuspid valve regurgitation. E /Ew was calculated as the parameter of RV diastolic function. Results The right VOI was 23±10%, the left VOI was 18±10%, and TVOI was 41±14%. The means with ranges of Sw, Ew, E /Ew, RVSP, and brain natriuretic peptide (BNP) were 10.7 (range 7.7–14.6) cm/s, 7.7 (range 4.2–10.6) cm/s, 5.0 (range 2.2–8.1), 55 (range 26–90) mm Hg, and 50.3 (range 12.2–165) pg/ml, respectively. The correlation coefficients between Sw, Ew, E /Ew, RVSP, and BNP and either larger of right or left side (LVOI) and TVOI were 0.041, −0.163 (Sw vs. LVOI, TVOI), −0.153, −0.232 (Ew vs. LVOI, TVOI), 0.145, 0.241 ( E /Ew vs. LVOI, TVOI), 0.255, 0.401 (RVSP vs. LVOI, TVOI), and 0.192, 0.170 (BNP vs. LVOI, TVOI), respectively. The correlation coefficient between RVSP and BNP was 0.390. Conclusions TVOI was better correlated with RVSP ( R =0.401) than the other parameters (Sw, Ew, E /Ew, and BNP), and this was similar to the degree that BNP was correlated with RVSP ( R =0.390). TVOI can be a better indicator of RVSP than LVOI. CT VOI may be a useful parameter to assess CPATE morphologically.