Background An explainable advanced electrocardiography (A-ECG) heart age gap is the difference between A-ECG heart age and chronological age. This gap is an estimate of accelerated cardiovascular ageing expressed in years of healthy human aging, and can intuitively communicate cardiovascular risk to the general population. However, existing A-ECG heart age measures require discernible P waves on the ECG.

Aims To develop and prognostically validate a revised, explainable A-ECG heart age gap without incorporating P-wave measures.

Methods An A-ECG heart age without P-wave measures (non-P) was derived from the 10-second 12-lead ECG in a derivation cohort using multivariable regression using an existing Bayesian 5-minute 12-lead A-ECG heart age as reference. The non-P heart age was externally validated in a separate cohort of patients referred for cardiovascular magnetic resonance imaging by describing its association with heart failure hospitalization or death using Cox regression, and its association with comorbidities.

Results In the derivation cohort (n=2771), A-ECG non-P heart age agreed with the 5-min heart age (R2=0.91, bias 0.0±6.7 years), and increased with increasing co-morbidity. In the validation cohort (n=731, mean age 54±15 years, 43% female, n=139 events over 5.7 [4.8–6.7] years follow-up), increased A-ECG non-P heart age gap (≥10 years) associated with events (hazard ratio [95% confidence interval] 2.04 [1.38–3.00], C-statistic 0.58 [0.54–0.62], and the presence of hypertension, diabetes mellitus, hypercholesterolemia, and heart failure (p≤0.009 for all).

Conclusions An explainable A-ECG non-P heart age gap applicable to both sinus and non-sinus rhythm associates with cardiovascular risk, cardiovascular morbidity, and survival.

The authors have declared no competing interest.

This study did not receive any funding.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

For the derivation cohort, Institutional Review Board (IRB) approvals were obtained from NASA's Johnson Space Center and partner hospitals that fall under IRB exemptions for previously collected and de-identified data. For the validation cohort, approval was obtained from the IRB at University of Pittsburgh Medical Center. Written consent was obtained for all participants for both cohorts, and all data was analyzed following de-identification.

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Funding: None Disclosures: ZAF, TL, ILP, AL, EBS, LN, MM: None; TTS is owner and founder of Nicollier-Schlegel SARL, which performs ECG interpretation consultancy using software that can quantify the advanced ECG measures used in the current study. TTS and MU are owners and founders of Advanced ECG Systems, a company that is developing commercial applications of advanced ECG technology used in the current study.

Data availability: Deidentified data of this study can be made available upon reasonable request to the corresponding author. Proposals for use will be reviewed on the basis of the scientific objective. A data use agreement will be required before the release of any raw results.

Deidentified data of this study can be made available upon reasonable request to the corresponding author.