Differences between systolic and diastolic dimensions of the aortic valve annulus in computed tomography angiography in patients undergoing percutaneous implantation of aortic valve prosthesis by catheter

Background

Accurate aortic valve annulus sizing has critical importance for the planning of percutaneous transcatheter aortic valve implantation (TAVI) in patients with severe aortic valve stenosis. Although there is a recommendation to perform the measurement during systole, little is known about the importance of the differences between systolic and diastolic dimensions of the annulus.

Methods

Consecutive patients referred for TAVI were evaluated with computed tomography for valve annulus sizing during systole and diastole. Area, circumference, minimum and maximum diameters, and their mean derived diameters were obtained in both phases of the cardiac cycle. Bland-Altman plots were constructed to evaluate the differences between the measures.

Results

The analysis included 41 patients with severe aortic stenosis. Mean area, circumference, and diameters were slightly greater in systole. However, in 35% of patients, diastolic dimensions were greater. These differences, although statistically significant, were small (the greatest difference of 0.6 mm in mean diameter). Bland-Altman plots showed good agreement between systolic and diastolic measurements on all parameters evaluated.

Conclusions

Small differences were observed in the systolic and diastolic dimensions of the aortic valve annulus with computed tomography scan, which, although statistically significant, probably do not impact the selection of prosthesis or the procedure outcome.