Interpretable and backpropagation-free Green Learning for efficient multi-task echocardiographic segmentation and classification

TL;DR

This paper introduces a novel, interpretable, and computationally efficient multi-task learning framework for echocardiographic segmentation and LVEF classification that outperforms existing deep learning models.

Contribution

The proposed backpropagation-free Green Learning framework combines unsupervised feature extraction with multi-task learning, achieving high accuracy with significantly fewer parameters.

Findings

Achieves 94.3% classification accuracy

Attains a Dice score of 0.912 for segmentation

Uses over an order of magnitude fewer parameters

Abstract

Echocardiography is a cornerstone for managing heart failure (HF), with Left Ventricular Ejection Fraction (LVEF) being a critical metric for guiding therapy. However, manual LVEF assessment suffers from high inter-observer variability, while existing Deep Learning (DL) models are often computationally intensive and data-hungry "black boxes" that impede clinical trust and adoption. Here, we propose a backpropagation-free multi-task Green Learning (MTGL) framework that performs simultaneous Left Ventricle (LV) segmentation and LVEF classification. Our framework integrates an unsupervised VoxelHop encoder for hierarchical spatio-temporal feature extraction with a multi-level regression decoder and an XG-Boost classifier. On the EchoNet-Dynamic dataset, our MTGL model achieves state-of-the-art classification and segmentation performance, attaining a classification accuracy of 94.3% and a Dice Similarity Coefficient (DSC) of 0.912, significantly outperforming several advanced 3D DL models. Crucially, our model achieves this with over an order of magnitude fewer parameters, demonstrating exceptional computational efficiency. This work demonstrates that the GL paradigm can deliver highly accurate, efficient, and interpretable solutions for complex medical image analysis, paving the way for more sustainable and trustworthy artificial intelligence in clinical practice.