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Cardiologist-level arrhythmia detection and classification in ambulatory electrocardiograms using a deep neural network

Nature Medicinevolume 25pages6569 (2019) | Download Citation


Computerized electrocardiogram (ECG) interpretation plays a critical role in the clinical ECG workflow1. Widely available digital ECG data and the algorithmic paradigm of deep learning2 present an opportunity to substantially improve the accuracy and scalability of automated ECG analysis. However, a comprehensive evaluation of an end-to-end deep learning approach for ECG analysis across a wide variety of diagnostic classes has not been previously reported. Here, we develop a deep neural network (DNN) to classify 12 rhythm classes using 91,232 single-lead ECGs from 53,549 patients who used a single-lead ambulatory ECG monitoring device. When validated against an independent test dataset annotated by a consensus committee of board-certified practicing cardiologists, the DNN achieved an average area under the receiver operating characteristic curve (ROC) of 0.97. The average F1 score, which is the harmonic mean of the positive predictive value and sensitivity, for the DNN (0.837) exceeded that of average cardiologists (0.780). With specificity fixed at the average specificity achieved by cardiologists, the sensitivity of the DNN exceeded the average cardiologist sensitivity for all rhythm classes. These findings demonstrate that an end-to-end deep learning approach can classify a broad range of distinct arrhythmias from single-lead ECGs with high diagnostic performance similar to that of cardiologists. If confirmed in clinical settings, this approach could reduce the rate of misdiagnosed computerized ECG interpretations and improve the efficiency of expert human ECG interpretation by accurately triaging or prioritizing the most urgent conditions.

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Data availability

The test dataset used to support the findings of this study is publicly available at https://irhythm.github.io/cardiol_test_set without restriction. Restrictions apply to the availability of the training dataset, which was used under license from iRhythm Technologies, Inc. for the current study. iRhythm Technologies, Inc. will consider requests to access the training data on an individual basis. Any data use will be restricted to noncommercial research purposes, and the data will only be made available on execution of appropriate data use agreements.

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iRhythm Technologies, Inc. provided financial support for the data annotation in this work. M.H. and C.B. are employees of iRhythm Technologies, Inc. A.Y.H. was funded by an NVIDIA fellowship. G.H.T. received support from the National Institutes of Health (K23 HL135274). The only financial support provided by iRhythm Technologies, Inc. for this study was for the data annotation. Data analysis and interpretation was performed independently from the sponsor. The corresponding author had full access to all the data in the study and had final responsibility for the decision to submit for publication.

Author information

Author notes

  1. These authors contributed equally: Awni Y. Hannun, Pranav Rajpurkar, Masoumeh Haghpanahi, Geoffrey H. Tison.


  1. Department of Computer Science, Stanford University, Stanford, CA, USA

    • Awni Y. Hannun
    • , Pranav Rajpurkar
    •  & Andrew Y. Ng
  2. iRhythm Technologies Inc., San Francisco, CA, USA

    • Masoumeh Haghpanahi
    •  & Codie Bourn
  3. Division of Cardiology, Department of Medicine, University of California San Francisco, San Francisco, CA, USA

    • Geoffrey H. Tison
  4. Department of Medicine and Center for Digital Health, Stanford University School of Medicine, Stanford, CA, USA

    • Mintu P. Turakhia
  5. Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, USA

    • Mintu P. Turakhia


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M.H., A.Y.N., A.Y.H., and G.H.T. contributed to the study design. M.H. and C.B. were responsible for data collection. P.R. and A.Y.H. ran the experiments and created the figures. G.H.T., P.R., and A.Y.H. contributed to the analysis. G.H.T., A.Y.H., and M.P.T. contributed to the data interpretation and to the writing. G.H.T., M.P.T., and A.Y.N. advised and A.Y.N. was the senior supervisor of the project. All authors read and approved the submitted manuscript.

Competing interests

M.H. and C.B. are employees of iRhythm Technologies, Inc. G.H.T. is an advisor to Cardiogram, Inc. M.P.T. is a consultant to iRhythm Technologies, Inc. None of the other authors have potential conflicts of interest.

Corresponding author

Correspondence to Awni Y. Hannun.

Extended data

  1. Extended Data Fig. 1 Deep Neural Network architecture.

    Our deep neural network consisted of 33 convolutional layers followed by a linear output layer into a softmax. The network accepts raw ECG data as input (sampled at 200 Hz, or 200 samples per second), and outputs a prediction of one out of 12 possible rhythm classes every 256 input samples.

  2. Extended Data Fig. 2 Receiver operating characteristic curves for deep neural network predictions on 12 rhythm classes.

    Individual cardiologist performance is indicated by the red crosses and averaged cardiologist performance is indicated by the green dot. The line represents the ROC curve of model performance. AF-atrial fibrillation/atrial flutter; AVB- atrioventricular block; EAR-ectopic atrial rhythm; IVR-idioventricular rhythm; SVT-supraventricular tachycardia; VT-ventricular tachycardia. n = 7,544 where each of the 328 30-second ECGs received 23 sequence-level predictions. Source data

Supplementary information

Source data

  1. Source data Fig. 1

    Sensitivity, specificity and PPV values at different operating points as well as the individual and average cardiologist metrics for the arrhythmias in the figure.

  2. Source data Fig. 2

    Absolute confusions counts between arrhythmias for both the model and the cardiologists.

  3. Extended data Fig. 2

    Sensitivity and specificity values at different operating points as well as the individual and average cardiologist metrics for all of the arrhythmias.

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