Diagnostic Performance of Cardiac CT and Transthoracic Echocardiography for Detection of Surgically Confirmed Bicuspid Aortic Valve: Effect of Calcium Extent and Valve Subtypes

Fig. 1. Classification of BAV. AP = anterior–posterior, BAV = bicuspid aortic valve, LA = latero-lateral, LN = left-non cusp fusion, RL = right-left cusp fusion, RN = right-non cusp fusion

Fig. 2. Enrollment flow chart.

Fig. 3. Cases diagnosed as BAV on CT and TAV on TTE among patients confirmed as BAV on surgical findings. A. A single coaptation line in diastole (left) and fish mouth appearance in systole (middle) are shown. At TTE, this case was diagnosed as TAV due to severe calcification and motion limitation (right). B. Two roughly equal cusps are observed in both diastole (left) and systole (middle). At TTE, this case was diagnosed as TAV due to poor echo window (right). BAV = bicuspid aortic valve, TAV = tricuspid aortic valve, TTE = transthoracic echocardiogram

Fig. 4. Changes in diagnostic performance based on calcium score. A. The solid line shows the sensitivity of the group higher than the corresponding calcium score, and the dotted line shows the sensitivity of the group lower than the corresponding calcium score. In both CT and TTE, the group with the high calcium score was less sensitive than the group with the low calcium score. CT showed higher sensitivity than TTE regardless of calcium score. As the calcium score increased, the sensitivity tended to decrease more in TTE than in CT. B-E. NPV and accuracy also show a similar tendency to sensitivity. NPV = negative predictive value, PPV = positive predictive value, TTE = transthoracic echocardiogram

Fig. 5. p-value for the difference in sensitivity between CT and TTE. The difference in sensitivity between CT and TTE in the group with lower than the corresponding calcium score was compared using McNemar’s test, and the p-value was graphed. The black solid line represents the raw p-value, and the black and green dots are the results of the correction of type 1 errors using the FDR and Holm method, respectively. The p-value reached statistical significance when the calcium score was approximately 1000. FDR = false discovery rate, TTE = transthoracic echocardiogram