Abstract
Although artificial intelligence (AI) algorithms have been shown to be capable of identifying cardiac dysfunction, defined as ejection fraction (EF) ≤ 40%, from 12-lead electrocardiograms (ECGs), identification of cardiac dysfunction using the single-lead ECG of a smartwatch has yet to be tested. In the present study, a prospective study in which patients of Mayo Clinic were invited by email to download a Mayo Clinic iPhone application that sends watch ECGs to a secure data platform, we examined patient engagement with the study app and the diagnostic utility of the ECGs. We digitally enrolled 2,454 unique patients (mean age 53 ± 15 years, 56% female) from 46 US states and 11 countries, who sent 125,610 ECGs to the data platform between August 2021 and February 2022; 421 participants had at least one watch-classified sinus rhythm ECG within 30 d of an echocardiogram, of whom 16 (3.8%) had an EF ≤ 40%. The AI algorithm detected patients with low EF with an area under the curve of 0.885 (95% confidence interval 0.823–0.946) and 0.881 (0.815–0.947), using the mean prediction within a 30-d window or the closest ECG relative to the echocardiogram that determined the EF, respectively. These findings indicate that consumer watch ECGs, acquired in nonclinical environments, can be used to identify patients with cardiac dysfunction, a potentially life-threatening and often asymptomatic condition.
This is a preview of subscription content, access via your institution
Relevant articles
Open Access articles citing this article.
-
Detection of left ventricular systolic dysfunction from single-lead electrocardiography adapted for portable and wearable devices
npj Digital Medicine Open Access 11 July 2023
Access options
Access Nature and 54 other Nature Portfolio journals
Get Nature+, our best-value online-access subscription
$29.99 / 30 days
cancel any time
Subscribe to this journal
Receive 12 print issues and online access
$209.00 per year
only $17.42 per issue
Rent or buy this article
Prices vary by article type
from$1.95
to$39.95
Prices may be subject to local taxes which are calculated during checkout



Data availability
The data are not publicly available because they are electronic health records. Sharing these data externally without additional consent might compromise patient privacy and would violate the study’s Institutional Review Board approval. If other investigators are interested in performing additional analyses, requests can be made to the corresponding author, P.F., and analyses could be performed in collaboration with the Mayo Clinic.
Code availability
The AI algorithm architecture has been previously published17. The code itself cannot be shared because it contains and is proprietary intellectual property (patent pending) that has been licensed and is under FDA review. We have been advised that, without FDA approval, the AI algorithm cannot be used in routine practice outside the Mayo Clinic.
References
Attia, Z. I., Harmon, D. M., Behr, E. R. & Friedman, P. A. Application of artificial intelligence to the electrocardiogram. Eur. Heart J. 42, 4717–4730 (2021).
Siontis, K. C., Noseworthy, P. A., Attia, Z. I. & Friedman, P. A. Artificial intelligence-enhanced electrocardiography in cardiovascular disease management. Nat. Rev. Cardiol. 18, 465–478 (2021).
Harmon, D. M., Attia, Z. I. & Friedman, P. A. Current and future implications of the artificial intelligence electrocardiogram: the transformation of healthcare and attendant research opportunities. Cardiovasc. Res. 118, e23–e25 (2022).
Attia, Z. I. et al. Screening for cardiac contractile dysfunction using an artificial intelligence-enabled electrocardiogram. Nat. Med. 25, 70–74 (2019).
Kwon, J. M. et al. Deep learning-based algorithm for detecting aortic stenosis using electrocardiography. J. Am. Heart Assoc. 9, e014717 (2020).
Ko, W. Y. et al. Detection of hypertrophic cardiomyopathy using a convolutional neural network-enabled electrocardiogram. J. Am. Coll. Cardiol. 75, 722–733 (2020).
Galloway, C. D. et al. Development and validation of a deep-learning model to screen for hyperkalemia from the electrocardiogram. JAMA Cardiol. 4, 428–436 (2019).
Kwon, J. M. et al. Artificial intelligence for detecting electrolyte imbalance using electrocardiography. Ann. Noninvasive Electrocardiol. 26, e12839 (2021).
Attia, Z. I. et al. An artificial intelligence-enabled ECG algorithm for the identification of patients with atrial fibrillation during sinus rhythm: a retrospective analysis of outcome prediction. Lancet 394, 861–867 (2019).
Echouffo-Tcheugui, J. B., Erqou, S., Butler, J., Yancy, C. W. & Fonarow, G. C. Assessing the risk of progression from asymptomatic left ventricular dysfunction to overt heart failure: a systematic overview and meta-analysis. JACC Heart Fail. 4, 237–248 (2016).
Ammar, K. A. et al. Prevalence and prognostic significance of heart failure stages: application of the American College of Cardiology/American Heart Association heart failure staging criteria in the community. Circulation 115, 1563–1570 (2007).
McDonagh, T. A., McDonald, K. & Maisel, A. S. Screening for asymptomatic left ventricular dysfunction using B-type natriuretic peptide. Congest Heart Fail 14, 5–8 (2008).
Attia, Z. I. et al. Prospective validation of a deep learning electrocardiogram algorithm for the detection of left ventricular systolic dysfunction. J. Cardiovasc. Electrophysiol. 30, 668–674 (2019).
Attia, I. Z. et al. External validation of a deep learning electrocardiogram algorithm to detect ventricular dysfunction. Int. J. Cardiol. 329, 130–135 (2021).
Adedinsewo, D. et al. Artificial intelligence-enabled ECG algorithm to identify patients with left ventricular systolic dysfunction presenting to the emergency department with dyspnea. Circ. Arrhythm. Electrophysiol. 13, e008437 (2020).
Noseworthy, P. A. et al. Assessing and mitigating bias in medical artificial intelligence: the effects of race and ethnicity on a deep learning model for ECG analysis. Circ. Arrhythm. Electrophysiol. 13, e007988 (2020).
Yao, X. et al. Artificial intelligence-enabled electrocardiograms for identification of patients with low ejection fraction: a pragmatic, randomized clinical trial. Nat. Med. 27, 815–819 (2021).
McDonagh, T. A. et al. 2021 ESC guidelines for the diagnosis and treatment of acute and chronic heart failure. Eur. Heart J. 42, 3599–3726 (2021).
Yancy, C. W. et al. 2017 ACC/AHA/HFSA focused update of the 2013 ACCF/AHA Guideline for the Management of Heart Failure: a report of the American College of Cardiology/American Heart Association Task Force on Cinical Practice Guidelines and the Heart Failure Society of America. Circulation 136, e137–e161 (2017).
Pisano, E. D. et al. Diagnostic performance of digital versus film mammography for breast-cancer screening. N. Engl. J. Med. 353, 1773–1783 (2005).
Cárdenas-Turanzas, M. et al. The accuracy of the Papanicolaou smear in the screening and diagnostic settings. J. Low. Genit. Trac. Dis. 12, 269–275 (2008).
Bhalla, V. et al. Diagnostic ability of B-type natriuretic peptide and impedance cardiography: testing to identify left ventricular dysfunction in hypertensive patients. Am. J. Hypertens. 18, 73s–81s (2005).
Perez, M. V. et al. Large-scale assessment of a smartwatch to identify atrial fibrillation. N. Engl. J. Med. 381, 1909–1917 (2019).
Benjamin, Z. I. et al. Correction to: Heart disease and stroke statistics—2018 update: a report from the American Heart Association. Circulation 137, e493 (2018).
Bui, A. L., Horwich, T. B. & Fonarow, G. C. Epidemiology and risk profile of heart failure. Nat. Rev. Cardiol. 8, 30–41 (2011).
Dargie, H. J. Effect of carvedilol on outcome after myocardial infarction in patients with left-ventricular dysfunction: the CAPRICORN randomised trial. Lancet 357, 1385–1390 (2001).
Pfeffer, M. A. et al. Effect of captopril on mortality and morbidity in patients with left ventricular dysfunction after myocardial infarction. Results of the survival and ventricular enlargement trial. The SAVE Investigators. N. Engl. J. Med. 327, 669–677 (1992).
Guo, Y. et al. Mobile photoplethysmographic technology to detect atrial fibrillation. J. Am. Coll. Cardiol. 74, 2365–2375 (2019).
Grogan, M. et al. Artificial intelligence-enhanced electrocardiogram for the early detection of cardiac amyloidosis. Mayo Clin. Proc. 96, 2768–2778 (2021).
Ahn, J. C. et al. Development of the AI-cirrhosis-ECG score: an electrocardiogram-based deep learning model in cirrhosis. Am. J. Gastroenterol. 117, 424–432 (2022).
Bailey, J. J. et al. Recommendations for standardization and specifications in automated electrocardiography: bandwidth and digital signal processing. A report for health professionals by an ad hoc writing group of the Committee on Electrocardiography and Cardiac Electrophysiology of the Council on Clinical Cardiology, American Heart Association. Circulation 81, 730–739 (1990).
Shiner, Z., Baharav, A. & Akselrod, S. Detection of different recumbent body positions from the electrocardiogram. Med. Biol. Eng. Comput. 41, 206–210 (2003).
Nelwan, S. P., Meij, S. H., van Dam, T. B. & Kors, J. A. Correction of ECG variations caused by body position changes and electrode placement during ST-T monitoring. J. Electrocardiol. 34, 213–216 (2001).
Williams, G. C. et al. The impact of posture on cardiac repolarization: more than heart rate? J. Cardiovasc. Electrophysiol. 17, 352–358 (2006).
Schijvenaars, B. J., Kors, J. A., van Herpen, G., Kornreich, F. & van Bemmel, J. H. Effect of electrode positioning on ECG interpretation by computer. J. Electrocardiol. 30, 247–256 (1997).
Heidenreich, P. A. et al. Forecasting the impact of heart failure in the united states: a policy statement from the American Heart Association. Circ. Heart Fail. 6, 606–619 (2013).
Mozaffarian, D. et al. Heart disease and stroke—2015 update: a report from the American Heart Association. Circulation 131, e29–e322 (2015).
Bahrami, H. et al. Differences in the incidence of congestive heart failure by ethnicity: the multi-ethnic study of atherosclerosis. Arch. Intern. Med. 168, 2138–2145 (2008).
Apple Inc. Using Apple Watch for Arrhythmia Detection https://www.apple.com/ca/healthcare/docs/site/Apple_Watch_Arrhythmia_Detection.pdf (Apple, 2020).
Steyerberg, E. W. & Harrell, F. E. Jr. Prediction models need appropriate internal, internal–external, and external validation. J. Clin. Epidemiol. 69, 245–247 (2016).
Tseng, A. S. et al. Cost effectiveness of an electrocardiographic deep learning algorithm to detect asymptomatic left ventricular dysfunction. Mayo Clinic Proc. 96, 1835–1844 (2021).
Cohen-Shelly, M. et al. Electrocardiogram screening for aortic valve stenosis using artificial intelligence. Eur. Heart J. 42, 2885–2896 (2021).
Attia, Z. I. et al. Age and sex estimation using artificial intelligence from standard 12-lead ECGs. Circ. Arrhythm. Electrophysiol. 12, e007284 (2019).
Thiele, C. & Hirschfeld, G. cutpointr: Improved estimation and validation of optimal cutpoints in R. J. Stat. Softw. 98, 1–27 (2021).
Acknowledgements
This publication was made possible through the support of the Ted and Loretta Rogers Cardiovascular Career Development Award Honoring H. C. Smith (to Z.I.A.). The Mayo Clinic CDH funded and developed the iPhone app used in the present study. The ECG dashboard used for clinician review was developed and supported by the Department of Cardiovascular Medicine. P.A.N. receives research funding from the National Institutes of Health (NIH, including the National Heart, Lung, and Blood Institute (grant nos. R21AG 62580-1, R01HL 131535-4 and R01HL 143070-2) and the National Institute on Aging (grant no. R01AG 062436-1)), the Agency for Healthcare Research and Quality (grant no. R01HS 25402-3), the Food and Drug Administration (FDA; grant no. FD 06292) and the American Heart Association (grant no. 18SFRN34230146). D.M.H. receives support from the NIH StARR Resident Investigator Award (grant no. 5R38HL150086-02). No technical or financial support was received from Apple.
Author information
Authors and Affiliations
Contributions
Z.I.A., J.D., P.A.F., B.L., R.E.C., R.K. and S.A. conceived the project and designed the analysis. Z.I.A., D.M.H., P.A.F., F.L.J., R.E.C., X.Y. and P.N. interpreted the data. Z.I.A., D.M.H., J.D., L.M., F.L.J., P.N., X.Y., R.E.C., S.A., R.K., B.L. and P.A.F. drafted the article or revised it critically for important intellectual content.
Corresponding author
Ethics declarations
Competing interests
The AI-ECG algorithm to detect left ventricular dysfunction was licensed by Mayo Clinic to Anumana, Eko health. P.A.F., Z.I.A., F.L.J., R.E.C., S.J.A. and other inventors and advisors to these entities may benefit financially from their commercialization. The remaining authors declare no competing interests.
Peer review
Peer review information
Nature Medicine thanks Partho Sengupta, Jill Waalen and Mohamed Elshazly for their contribution to the peer review of this work. Primary Handling Editor: Michael Basson, in collaboration with the Nature Medicine team.
Additional information
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Extended data
Extended Data Fig. 1 Patient study invitations by month.
Batch invitations sent to Mayo Clinic app patients on a monthly basis.
Extended Data Fig. 2 EMR-integrated AI Dashboard with Apple Watch ECG data.
Panel A shows the 12 lead ECGs and AI derived scores to multiple AI-ECG models, Panel B shows the watch ECG tracings from the same patient.
Extended Data Fig. 3 Morphological differences between Apple watch and Lead 1 from 12 Lead.
12 Lead ECG recording versus post-processing Apple Watch ECG. Significant high frequency signal loss resulted in visual loss of some characteristics present on the standard 12-lead ECG such as pacing spikes that were absent in the Apple watch ECG.
Extended Data Fig. 4 Patient provider interaction using the AI dashboard.
Case example for patient with new atrial fibrillation on Apple Watch ECG without prior clinical history of atrial fibrillation.
Supplementary information
Rights and permissions
Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Attia, Z.I., Harmon, D.M., Dugan, J. et al. Prospective evaluation of smartwatch-enabled detection of left ventricular dysfunction. Nat Med 28, 2497–2503 (2022). https://doi.org/10.1038/s41591-022-02053-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/s41591-022-02053-1
This article is cited by
-
Smartwatch detection of left ventricular dysfunction
Nature Reviews Cardiology (2023)
-
Detection of left ventricular systolic dysfunction from single-lead electrocardiography adapted for portable and wearable devices
npj Digital Medicine (2023)