Aortic valve calcium score for paravalvular aortic insufficiency (AVCS II) study in transapical aortic valve implantation

Abstract

Background: Transapical aortic valve implantation (TAAVI) has evolved into a routine procedure for select highrisk patients. The aim was to study the impact of native aortic valve calcification on paravalvular leaks in cardiac contrastenhanced computed tomography (CT). Methods: The degree and distribution of valve calcification were quantified using an Aortic Valve Calcium Score (AVCS) for each cusp separately (3mensio Valves). To reduce an artificial increase of the AVCS due to the presence of contrast material, we used thresholds for density [mean aortic density + 2∗SD] and volume [0, 3, 5, 25, and 50 mm3] of calcification. Results: 111 consecutive patients prior to TAAVI with preoperative CT aged 79.8 ± 5.8 years were included using the Edwards Sapien prosthesis. Paravalvular leaks were significantly associated with eccentric calcified plaques (r [Spearman] = 0.37; X2-statistic = 15.4; P = .002), presence of LVOT calcium (r [Spearman] = 0.28; X2-statistic = 11.3; P = .009), and the commissural gap at the anatomic ventriculo-arterial junction (r [Spearman] = 0.41-0.63; X2-statistic = 50.8-53.0; P = .002-..001). There was no significant association between the total AVCS and PV leaks (r [Spearman] = 0.076; X2-statistic = 1.471; P = .240, 120 kV, 850 hounsfield units) with no additional use of a volume-based threshold. Conclusion: Asymmetry of leaflet calcium distribution, LVOT calcium, and the commissural gap between leaflets were significantly associated with paravalvular leaks. Moreover, quantification of aortic valve calcification in contrast enhanced CTs shows only a weak correlation with paravalvular leakage and is therefore not reliable as a predictor, respectively.