Cardiovasc Imaging Asia.  2021 Jul;5(3):72-78. 10.22468/cvia.2021.00178.

Correlation of Aortic Valve Calcification Volume Using Cardiac-Gated Contrast-Enhanced CT with Aortic Stenosis Severity Using Echocardiographic Indices

• Ngam PI
• Ong CC
• Wui Tay EL
• Fatt Hon JK
• Liang C
• San Teo LL

• KMID: 2519016
• DOI: http://doi.org/10.22468/cvia.2021.00178

Abstract

Objective
The aim of the study is to assess feasibility of using aortic valve calcification volume (AVCV) as a surrogate marker for aortic stenosis (AS) by studying the correlation between AVCV on contrast enhanced CT (CECT) and severity of AS using echocardiographic indices.
Materials and Methods
Ninety-four patients with AS, who underwent CECT and echocardiography as part of pre-transcatheter aortic valve implantation assessment were analysed. AVC was quantified on CECT using methodology validated by Bischoff et al. Severity of AS was categorized by echocardiography indices [transaortic jet velocity, mean pressure gradient, aortic valve area (AVA) by continuity and planimetry equations, indexed AVA to body surface area and dimensionless index (DI)].
Results
Moderate to strong correlation was found between AVCV with transaortic jet velocity (rs=0.397, p<0.001), peak pressure gradient (rs=0.410, p<0.001) and mean pressure gradient (rs=0.381, p<0.001). There was statistically significant correlation between AVCV with indexed AVA (rs=-0.225, p<0.001) and DI (rs=-0.644 p<0.001) but not with AVA by continuity equation (rs=-0.024, p<0.826) and by planimetry (rs=-0.185, p<0.158). Although not statistically significant, patients with higher degree of AS were noted to have higher AVCV burden on CECT.
Conclusion
Quantification of AVCV using CECT is a potential complementary marker for grading of AS severity. AVCV has additive value when there is discrepancy between clinical and echocardiography examinations or discordant echocardiographic indices due to variation in techniques of imaging and small body size in Asian population.

Keyword

Aortic valve disease; Aortic valve stenosis; Transcatheter aortic valve replacement; Echocardiography; Computed tomography angiography