Nghiên Cứu Vai Trò Của Chụp Cắt Lớp Vi Tính 256 Dãy Trong đánh Giá ...

SUMMARY

Objective: To compare DSCT using 256-slice coronary CT angiography (SOMATOMA Definition FLASH, Siemens Medical Solution, Germany) with echocardiography for the determination of left ventrical dimentions, left ventricular ejection fraction (LVEF), end-diastolic volume (EDV), end-systolic volume (ESV), regional wall motion as well as assessing coronary artery image quality and patient radiation dose.

Materials and Methods: One-hundred twelve patients were referred for DSCT for evaluation of coronary artery and underwent DSCT and transthoracal echocardiography within 1 week. LV dimentions, EF, EDV and ESV were determined for both DSCT and echocardiography, and the correlation coefficients were assessed. Measurements of dimensions were obtained in standardized planes in end-systole and end-diastole and included the septal and posterior wall thickness, and inner diameter of the left ventricle. Global left ventricular (LV) functional parameters [end-systolic volume (ESV), end-diastolic volume (EDV), ejection fraction] were computed using automated software. ESV, EDV were normalized to the body-surface-area (BSA). Correlation between DSCT and echocardiography was tested through linear regression and Bland- Altman analysis. Regional wall motion is collected by visual (1, normal, 2, hypokinesia, 3, dysphagia or akinesia). Coronary artery segment subjective image quality (1, excellent; 4, poor) and radiation dose were recorded.

Results: A direct comparison between 256 slice Dual-Source CT and 2D-echocardiography was performed in 112 patients (43men; 61,26 ± 11,68 mean age years) who were clinically referred for MSCT coronary angiography. LV end-diastolic volumes (LVEDV) and LV endsystolic volumes (LVESV) were determined and the LV ejection fraction (LVEF) was derived. Average LVEF was 66,24± 13,52% (range 23-85%) as determined on DSCT, compared with 65,72±11,31% (range 25-84%) on 2D echocardiography. Evaluation of LVEF by linear regression analysis showed a good correlation between DSCT and 2D-echocardiography (r= 0,715; P < .001). Good correlations between DSCT and 2D-echocardiography were demonstrated for the assessment of LVEDV (r=0,732 ; P < .001) and LVESV (r= 0,841; P < .001). At Bland-Altman analysis, mean differences (±SD) of 1,78 ± 24,10 mL (p <0 .05) and 0,766 ± 13,7 mL (p < 0.05) were observed between DSCT and 2D-echocardiography for LVEDV and LVESV, respectively. LVEF was slightly overestimated with DSCT (0.52 ± 9,59%; p < 0.05). Resultly, the LVEFs calculated by DSCT and echocardiography were not statistically different. However, LVEF, EDV and ESV from MDCT were statistically higher than those from echocardiography (p < 0.05).The average image quality score of the coronary artery segment was 1,79. The mean patient radiation dose was 3,78 ±1,88 mSv.

Conclusion: In conclusion, the use of 256-slice DSCT can provide comparable results to those using 2D-TTE for LV funtion include EF, EDV, ESV and regional wall motion assessment in a heterogeneous population.

Keywords: DSCT; Coronary Artery Disease; Left ventricular function; Echocardiography; Radiation