Four-dimensional analysis of aortic root motion in normal population using retrospective multiphase computed...

Area of Science:

• Cardiovascular imaging
• Biomechanical analysis
• Aortic disease research

Background:

• Aortic root motion is implicated in proximal aortic dissection.
• Quantitative assessment of aortic root displacement and rotation is currently limited.
• Understanding aortic root biomechanics is crucial for managing aortopathy.

Purpose of the Study:

• To demonstrate the feasibility of quantifying three-dimensional aortic root motion using dynamic CT imaging.
• To establish a method for measuring aortic root displacement and rotation in vivo.
• To provide normative data for aortic root motion.

Main Methods:

• Utilized dynamic CT scans from 40 patients acquired for coronary assessment.
• ECG-triggered scans were segmented into 10 phases per cardiac cycle.
• A patient-specific coordinate system was created to quantify out-of-plane, in-plane, and rotational motion of the aortic root.

Main Results:

• Largest out-of-plane motion: 10.26 ± 2.20 mm (left coronary ostia) and 8.67 ± 1.69 mm (right coronary ostia).
• Mean downward movement of the aortic root was 9.13 ± 1.86 mm.
• Largest in-plane motion: 9.17 ± 2.33 mm (left) and 6.51 ± 1.75 mm (right). Aortic root rotation measured 11.8 ± 4.60°.

Conclusions:

• Spatial and temporal displacement of the aortic root can be quantified from multiphase ECG-gated contrast-enhanced CT images.
• This technique allows for in vivo assessment of aortic root motion.
• Knowledge of normal aortic root motion aids in understanding its biomechanical role in aortopathy and guiding treatment decisions.