Four-dimensional Cardiac Modelling of Multiphase Computed Tomography for Predicting Outcomes After Transcatheter...

Area of Science:

• Cardiology
• Medical Imaging
• Biomedical Engineering

Background:

• Multiphase computed tomography angiography (mpCTA) is standard for transcatheter aortic valve replacement (TAVR) eligibility and planning.
• Assessing cardiac chamber contractile health using full-cycle, multiphase reconstructions may offer prognostic insights.
• This study explored 4-dimensional (4D) left ventricular (LV) chamber modeling to predict TAVR outcomes via 3D minimum principal strain (3DminPS).

Purpose of the Study:

• To assess the feasibility of 4D LV chamber modeling using mpCTA data.
• To determine if 3DminPS derived from 4D modeling can predict clinical outcomes after TAVR.
• To evaluate the prognostic value of endocardial, epicardial, and transmural 3DminPS.

Main Methods:

• 205 patients undergoing pre-TAVR mpCTA were analyzed.
• UNet-based 3D chamber segmentation was performed, followed by mesh modeling and 3D feature tracking.
• Global 3DminPS was calculated for different myocardial layers to assess associations with heart failure hospitalization or death.

Main Results:

• Analyzable mpCTAs were obtained from 196 patients (96%).
• At a median of 25 months post-TAVR, 28% of patients experienced the primary outcome (heart failure hospitalization or death).
• An endocardial 3DminPS worse than -23.7% was independently associated with a 2.7-fold increased risk of the primary outcome (aHR=2.7, P=0.001).

Conclusions:

• 4D chamber modeling of mpCTA is feasible using UNet segmentation and mesh deformation.
• This technique provides 3D deformation markers with significant prognostic value for TAVR outcomes.
• Prospective multicenter validation of this approach is currently underway.