AI-enabled privacy-preserving cardiac diagnostics via electrocardiograms

Electrocardiogram (ECG) is a widely available, non-invasive diagnostic tool used for cardiovascular screening and provides essential insights into heart rhythm, structure, and function. However, the high dimensionality of ECGs and their entanglement with demographic information pose challenges for building fair and privacy-preserving machine learning models. ECG signals inherently encode soft biometric attributes such as sex, age, and race, which may introduce bias and raise privacy concerns in data-sharing environments. To address these challenges, we propose a deep learning framework that learns clinically relevant ECG representations while suppressing sensitive demographic information. We leverage a variational autoencoder (VAE) with a dual-discriminator architecture. One adversarial branch reduces soft biometric encoding, while the other preserves clinically important discrimination of reduced left ventricular ejection fraction (LVEF). The privacy-preserving reconstructed ECGs reduced identifiability of soft biometrics by independent CNN models with AUROC for sex 0.59 (from original 0.79), age 0.63 (from 0.78), and race 0.57 (from 0.69), while retaining clinically-useful predictions like reduced LVEF 0.82 (from 0.86), left ventricular hypertrophy (LVH) 0.72 (from 0.75), and 5-year mortality 0.67 (from 0.66). These findings demonstrate the effectiveness of our approach for retaining ECG data yet protecting patient privacy.