A Cycle-Consistent Graph Surrogate for Full-Cycle Left Ventricular Myocardial Biomechanics

TL;DR

This paper introduces CardioGraphFENet, a graph-based surrogate model that efficiently predicts full-cycle left ventricular biomechanics from complex geometries, reducing reliance on computationally intensive finite-element analysis.

Contribution

The paper presents a novel unified graph neural network architecture that achieves accurate full-cycle LV biomechanics prediction with cycle-consistency, reducing FEA supervision needs.

Findings

High fidelity predictions matching FEA ground truths

Physiologically plausible pressure-volume loops

Significant reduction in FEA supervision required

Abstract

Image-based patient-specific simulation of left ventricular (LV) mechanics is valuable for understanding cardiac function and supporting clinical intervention planning, but conventional finite-element analysis (FEA) is computationally intensive. Current graph-based surrogates do not have full-cycle prediction capabilities, and physics-informed neural networks often struggle to converge on complex cardiac geometries. We present CardioGraphFENet (CGFENet), a unified graph-based surrogate for rapid full-cycle estimation of LV myocardial biomechanics, supervised by a large FEA simulation dataset. The proposed model integrates (i) a global--local graph encoder to capture mesh features with weak-form-inspired global coupling, (ii) a gated recurrent unit-based temporal encoder conditioned on the target volume-time signal to model cycle-coherent dynamics, and (iii) a cycle-consistent bidirectional formulation for both loading and inverse unloading within a single framework. These strategies enable high fidelity with respect to traditional FEA ground truths and produce physiologically plausible pressure-volume loops that match FEA results when coupled with a lumped-parameter model. In particular, the cycle-consistency strategy enables a significant reduction in FEA supervision with only minimal loss in accuracy.