Objective: Limited information is available regarding distribution and initiation of aortic valve (AV) calcification, which is an important precursor of clinical valve stenosis. The aim of the present study is to: 1) Quantify calcification volumes in aortic cusps; 2) Study the early stages of calcification initiation and growth process using a new computational method in patients with symptomatic severe aortic stenosis
Method: AV calcification was measured by computed tomography (CT) in 52 patients and in a subgroup of 10 patients. A New Reverse Calcification Technique (RCT) was used to study the initiation of AV calcification. The RCT is based on CT spatial Hounsfield Unit (HU) distribution of calcification density in the AV. Using a density subtraction algorithm, the RCT is able to reach the backward-evolution and initiation of AV calcification.
Results: Non-coronary cusp's calcification volume (565 ± 368mm³) was significantly higher than the left and right coronary cusp, 404 ± 214 mm³ and 378 ± 246 mm³; respectively, P = 0.02). Using the reverse calcification technique, the volume of the non-coronary calcification was found to be larger than the coronary, starting from initiation to severe stenosis stage.
Conclusions:
The non-coronary cusp was found to be more prone to increased and preferential calcification than the left and right cusp. The calcification of the non-coronary has larger volume and higher density. The new developed RCT method was able to show the initiation and growth process of the calcification. It is suggested that the different mechanical environment of the non-coronary cusp is the cause for its increased calcification.
