Embedding High-dimensional Bayesian Optimization via Generative Modeling - Parameter Personalization of Cardiac Electrophysiological Models

Abstract

The estimation of patient-specific tissue properties in the form of model parameters is important for personalized physiological models. Because tissue properties are spatially varying across the underlying geometrical model, it presents a significant challenge of high-dimensional (HD) optimization at the presence of limited measurement data. A common solution to reduce the dimension of the parameter space is to explicitly partition the geometrical mesh. In this paper, we present a novel concept that uses a generative variational auto-encoder (VAE) to embed HD Bayesian optimization into a low-dimensional (LD) latent space that represents the generative code of HD parameters. We further utilize VAE-encoded knowledge about the generative code to guide the exploration of the search space. The presented method is applied to estimating tissue excitability in a cardiac electrophysiological model in a range of synthetic and real-data experiments, through which we demonstrate its improved accuracy and substantially reduced computational cost in comparison to existing methods that rely on geometry-based reduction of the HD parameter space.

Publication
In Medical Image Analysis.
Pradeep Bajracharya
Pradeep Bajracharya
PhD Student in Machine Learning

My research interests include Deep Active Learning, Bayesian Active Learning, Uncertainty Quantification, Deep Learning, and Machine Learning