Aortic valve area on 64-MDCT correlates with transesophageal echocardiography in aortic stenosis

Abstract

Objective: The purpose of our study was to compare aortic valve area and calcification between CT and echocardiography.

Materials and methods: We performed retrospective evaluation of 80 consecutive patients with aortic stenosis (AS) who underwent ECG-gated 64-MDCT and transesophageal echocardiography (TEE). Valve planimetry was feasible in 80 patients with CT and in 63 patients with TEE; valve area by transthoracic echocardiography was available in 46 patients. Valve calcification grade on CT was compared with TEE. One cardiologist (echocardiography) and two radiologists (CT) independently and blindly reviewed the studies. Pearson's correlations, Spearman's rank correlations, paired Student's t tests, and weighted kappa tests were used.

Results: The median valve area on TEE was 0.7 +/- 0.9 cm(2). There was excellent correlation (n = 80; r = 0.91, p < 0.001) and no difference (0.06 +/- 0.26 cm(2), p = 0.06) between CT readers. There was strong correlation (n = 63; r = 0.84, p < 0.001) and no difference (-0.06 +/- 0.48 cm(2), p = 0.33) in valve area between CT and TEE, with a strong correlation (n = 46; r = 0.83, p < 0.001) and small overestimation (0.17 +/- 0.33 cm(2), p < 0.001) in valve area with CT versus transthoracic echocardiography. The sensitivity and specificity of CT to detect severe aortic stenosis compared with TEE were 92.1% (35/38) and 89.5% (17/19), respectively. Calcification grade had fair agreement between CT readers and TEE (kappa = 0.34 and 0.37, respectively).

Conclusion: Aortic valve area on CT strongly correlates with echocardiography and has excellent sensitivity and specificity to detect severe stenosis. Valve calcification has fair agreement between studies. Valve area and calcification should be reported on CT angiography in patients with AS.