Aortic valve calcification is subject to aortic stenosis severity and the underlying flow pattern

Area of Science:

• Cardiovascular Imaging
• Radiology
• Cardiac Pathology

Background:

• Aortic valve calcification (AVC) studies are limited, with scarce data on calcium quantity and distribution.
• Understanding AVC is crucial for distinguishing moderate from severe aortic stenosis (AS).

Purpose of the Study:

• To redefine AVC thresholds for differentiating severe from moderate AS.
• To evaluate differences in aortic annulus and left ventricular outflow tract (LVOT) calcium load across AS entities.

Main Methods:

• Retrospective analysis of 938 patients with moderate-to-severe AS using cardiac MSCT.
• Categorization into high gradient (HGAS), paradoxical low gradient (pLGAS), and classical low gradient (LGAS) AS entities.
• Quantification of AVC, leaflet, and LVOT calcification.

Main Results:

• Severe HGAS showed the highest AVC scores; severe pLGAS and LGAS had lower scores.
• The non-coronary cusp (NCC) was consistently the most calcified.
• Logistic regression accuracy for diagnosing severe AS was highest in HGAS, with specific AVC thresholds identified for men and women.
• AVC distinguished severe LGAS from moderate AS only in men; LVOT calcification was not a reliable indicator.

Conclusions:

• The NCC is predominantly affected by degeneration across AS severities and entities.
• AVC can differentiate severe from moderate AS in men with LGAS.
• LVOT calcification is not a reliable indicator of AS progression.