Assessment of aortic stenosis with dual-source CT

Objective To discuss the feasibility and accuracy of dual-source CT ( DSCT) in the evaluation of aortic stenosis ( AS) with transthoracic echocardiography ( TTE) as reference.Methods A total of 53 patients who underwent both DSCT and TTE were prospectively evaluated.All of them were assessed by TTE for aortic stenosis.Maximum aortic valve area ( AVA) in systolic phase was measured with DSCT , and was compared to that index obtained from the continuity equation on TTE.The severity of AS was graded as mild , moderate , or severe according to the AVA.Linear regression analysis and Bland-Altman plots were used to compare the AVA measured by using CT and TTE.Agreement on semi-quantitative grades of AS severity between the two methods was tested by using Kappa statistics.Results The mean AVA using DSCT was (1.45 ±0.35 ) cm2 compared to the mean AVA of ( 1.33 ±0.36 ) cm2 using TTE, with a significant correlation between them (r=0.92,P<0.01).Bland-Altman analysis demonstrated good inter-modality consistency between DSCT and TTE.However , DSCT demonstrated a slight overestimation of the AVA compared to TTE.As identified by TTE, there were 53 patients with AS, 13 with mild AS, 21 with moderate AS , and 19 with severe AS.In 3 patients DSCT showed no AS , TTE detected mild AS.In 6 cases, TTE had graded the stenosis as moderate , but the stenosis degree was graded as mild using DSCT.Kappa analysis showed a good agreement between the two methods on semi -quantitative grades of aortic stenosis severity (Kappa=0.75,P<0.01).Conclusion AVA measurements using DSCT is feasible and reasonably accurate for those patients with moderate to severe aortic stenosis. Key words: Aortic valve stenosis ;  Tomography,X-ray computed ;  Echocardiography ;