A method for standardized computed tomography angiography-based measurement of aortic valvar structures

Area of Science:

• Cardiovascular Imaging
• Anatomical Measurement Techniques
• Interventional Cardiology

Background:

• Accurate assessment of the aortic valvar apparatus (AVAp) is critical for successful percutaneous aortic valvar therapies.
• The traditional aortic annulus measurement lacks anatomical correlation, posing challenges for procedural planning.
• Computed tomography (CT) offers a potential platform for precise AVAp structural assessment.

Purpose of the Study:

• To develop and validate a reliable CT-based method for measuring key anatomical structures of the AVAp.
• To establish the inter-rater reliability and absolute agreement of these novel measurements.

Main Methods:

• Retrospective analysis of CT scans from 75 patients with severe aortic stenosis.
• Utilized curved multiplanar reconstruction to measure diameters of the Aortic Leaflets Basal Attachment Plane (ALBAP), sinuses of Valsalva (SV), sinutubular junction (STJ), and ascending aorta (AA).
• Assessed inter-rater reliability and absolute agreement using intra-class correlation coefficients.

Main Results:

• High inter-rater reliability (ICC > 0.90) and agreement (<1 mm difference) were observed for ALBAP, SV, STJ, and AA diameters.
• Reliability was lower for the aorto-left ventricular angle (ICC=0.82) and coronary artery distances (ICC=0.61-0.78).

Conclusions:

• The proposed CT method demonstrates high reliability for measuring AVAp diameters, essential for percutaneous aortic valve therapies.
• Further software and protocol standardization are needed to improve accuracy for angular and coronary artery distance measurements.