ECG abnormalities are strongly associated with incident heart failure events in low-risk individuals using the...

Resting electrocardiogram (ECG) are associated with heart failure (HF) events, even though it is not currently recommended in risk assessment. The role of ECG abnormalities is not clear in identifying at risk individuals.

To examine the association between ECG abnormalities and incident HF events according to the 2023 Predicting Risk of Cardiovascular Disease Events (PREVENT) HF equation. And identify a subgroup of individuals who are misclassified as being at low risk and may benefit from primary intervention measures.

Secondary data analysis from the REasons for Geographic And Racial Differences in Stroke (REGARDS) prospective cohort, including study participants without baseline HF.

ECG abnormalities were classified by Minnesota Code (MC) as normal, any minor, or any major abnormality at baseline (2003-2007).

Participants were followed for expert adjudicated incident HF hospitalizations/deaths through December 31, 2021.

Among 20,923 participants (mean age at baseline of 63.6 years, 53.7% were female), 26.0% of the sample was classified as low risk (<3%), 17.5% as borderline risk (3-<5%), 27.5% as intermediate risk (5%-<10%), and 29.0% as high risk (≥10%). Overall, 43.8% had normal ECG, 41.7% had at least one minor abnormality, and 14.5% had at least one major abnormality. HF events occurred in 3.3% of the sample with normal ECG, 6.2% of those with any minor abnormality, and 13.2% of those with any major ECG abnormality. Compared to those without ECG abnormality, the adjusted HR for incident HF was 1.56 (95% CI 1.35-1.80) for any minor abnormality and 2.56 (2.18-3.00) for any major abnormality. 43.5% of the population were in the less than 5% risk by PREVENT among whom 45.8% had any ECG abnormalities. The fully adjusted HR for only minor ECG abnormalities in the <3% was 1.47 (95% CI 0.72-3.01), and the fully adjusted HR for any major ECG abnormality was 5.22 (95% CI 2.42-11.30). In the borderline risk group, the fully adjusted HR for only minor ECG abnormalities was 1.37 (95% CI 0.89 - 2.11), and the fully adjusted HR for any major ECG abnormality was stronger than the HR in the intermediate and high-risk groups; 3.05 (95% CI 1.85 - 5.03).

ECG abnormalities were common and associated with HF events across all PREVENT risk groups, especially in the low/borderline risk groups with major ECG abnormalities. ECG may be useful to identify at-risk individuals who would otherwise be misclassified as lower risk patients.