Abnormal electrocardiogram and poor prognosis in heart failure with preserved ejection fraction

Postgrad Med J. 2023 Oct 19;99(1177):1154-1159. doi: 10.1093/postmj/qgad055.

Abstract

Purpose: Electrocardiogram (ECG) is generally performed in patients with heart failure with preserved ejection fraction (HFpEF), but the prognostic value of abnormal ECG is not fully understood. We aim to explore the prognostic value of abnormal ECG at baseline in HFpEF using data from the TOPCAT trial.

Methods: A total of 1736 patients from TOPCAT-Americas were included and divided into normal versus abnormal ECG groups. Survival analyses were performed for the following outcomes: the primary endpoint [a composite of cardiovascular death, heart failure (HF) hospitalization, and aborted cardiac arrest], all-cause death, cardiovascular death, and HF hospitalization.

Results: Abnormal ECG was significantly associated with higher risks of the primary endpoint [hazard ratio (HR): 1.480, P = 0.001] and HF hospitalization (HR: 1.400, P = 0.015), and borderline significantly with cardiovascular death (HR: 1.453, P = 0.052) in patients with HFpEF after multivariate adjustment. As for specific ECG abnormalities, bundle branch block was associated with the primary endpoint (HR: 1.278, P = 0.020) and HF hospitalization (HR: 1.333, P = 0.016), whereas atrial fibrillation/flutter was associated with all-cause death (HR: 1.345, P = 0.051) and cardiovascular death (HR: 1.570, P = 0.023), but ventricular paced rhythm, pathological Q waves, and left ventricular hypertrophy were not of prognostic significance. Besides, other unspecific abnormalities together were associated with the primary endpoint (HR: 1.213, P = 0.032).

Conclusion: Abnormal ECG at baseline could be associated with poor prognosis in patients with HFpEF. Physicians are encouraged to pay more attention to HFpEF patients who present an abnormal ECG instead of ignoring those obscure abnormalities. Key messages What is already known on this topic Electrocardiogram (ECG) is a basic and easily accessible examination for patients with heart failure with preserved ejection fraction (HFpEF). Some findings from ECG such as frontal QRS-T angle, QTc interval, and the Cornell product have been shown to be associated with the prognosis of HFpEF but these results are from studies with relatively small sample sizes. What this study adds Using data from TOPCAT-Americas, this study found that an overall estimation of abnormal ECG significantly predicted poor prognosis in patients with HFpEF. As for specific abnormalities in ECG, bundle branch block mainly predicted heart failure hospitalization and atrial fibrillation mainly predicted death. How this study might affect research, practice, or policy This study reminds physicians to pay more attention to HFpEF patients who present an abnormal ECG.

Keywords: electrocardiography; heart failure; prognosis.