Quantitative estimation of aortic valve calcification in multislice computed tomography in predicting the development of paravalvular leaks following transcatheter aortic valve replacement

Introduction
Transcatheter aortic valve implantation (TAVI) improves prognosis in patients disqualified from surgical valve replacement. Calcifications of the aortic complex can lead to deformation of the prosthesis, resulting in paravalvular leaks (PVL).

Aim
To evaluate the predictive value of quantitative estimation of volume/weight and geometric distribution of calcifications in multislice computed tomography, for the development of PVL.

Material and methods
This was a retrospective, case-control study on patients with a CoreValve aortic prosthesis. The study group consisted of 20 patients with confirmed significant PVL after TAVI. The control group consisted of 20 patients without significant PVL, matched according to valve type and clinical characteristics. The size spatial distribution and shape of calcifications were measured.

Results
The average age of patients was 79.9 years (60% women). Cases and controls did not differ in their clinical characteristics. The size of the aortic annulus was significantly larger in cases vs. controls (23.4 ±1.6 vs. 22 ±1.4 mm, p = 0.01). Volume, area and curvature of calcifications were greater in cases vs controls (1.09 ±0.56 vs. 0.59 ±0.41 cm3, p = 0.011; 15.26 ±5.46 vs. 9.50 ±5.29 cm2, p = 0.008; 1.76 ±0.07 vs. 1.68 ±0.13 cm3, p = 0.037). In multivariate analysis, adjusted for aortic annulus size, the area of aortic valve calcifications independently predicted paravalvular regurgitation (OR = 1.41, 95% CI: 0.09–1.92, p < 0.009).

Conclusions
Morphometric analysis of aortic valve calcifications predicted the risk of paravalvular leak following TAVI irrespectively of patients’ clinical characteristics.