Deep learned representations of the resting 12-lead electrocardiogram to predict at peak exercise

Abstract

Abstract Aims To leverage deep learning on the resting 12-lead electrocardiogram (ECG) to estimate peak oxygen consumption (V˙O2peak) without cardiopulmonary exercise testing (CPET). Methods and results V ˙ O 2 peak estimation models were developed in 1891 individuals undergoing CPET at Massachusetts General Hospital (age 45 ± 19 years, 38% female) and validated in a separate test set (MGH Test, n = 448) and external sample (BWH Test, n = 1076). Three penalized linear models were compared: (i) age, sex, and body mass index (‘Basic’), (ii) Basic plus standard ECG measurements (‘Basic + ECG Parameters’), and (iii) basic plus 320 deep learning-derived ECG variables instead of ECG measurements (‘Deep ECG-V˙O2’). Associations between estimated V˙O2peak and incident disease were assessed using proportional hazards models within 84 718 primary care patients without CPET. Inference ECGs preceded CPET by 7 days (median, interquartile range 27–0 days). Among models, Deep ECG-V˙O2 was most accurate in MGH Test [r = 0.845, 95% confidence interval (CI) 0.817–0.870; mean absolute error (MAE) 5.84, 95% CI 5.39–6.29] and BWH Test (r = 0.552, 95% CI 0.509–0.592, MAE 6.49, 95% CI 6.21–6.67). Deep ECG-V˙O2 also outperformed the Wasserman, Jones, and FRIEND reference equations (P < 0.01 for comparisons of correlation). Performance was higher in BWH Test when individuals with heart failure (HF) were excluded (r = 0.628, 95% CI 0.567–0.682; MAE 5.97, 95% CI 5.57–6.37). Deep ECG-V˙O2 estimated V˙O2peak <14 mL/kg/min was associated with increased risks of incident atrial fibrillation [hazard ratio 1.36 (95% CI 1.21–1.54)], myocardial infarction [1.21 (1.02–1.45)], HF [1.67 (1.49–1.88)], and death [1.84 (1.68–2.03)]. Conclusion Deep learning-enabled analysis of the resting 12-lead ECG can estimate exercise capacity (V˙O2peak) at scale to enable efficient cardiovascular risk stratification.