Aims: Little is known about ECG abnormalities in patients with heart failure and normal ejection fraction (HeFNEF) and how they relate to different aetiologies or outcomes.
Methods and results: We searched the literature for peer-reviewed studies describing ECG abnormalities in HeFNEF other than heart rhythm alone. Thirty-eight studies were identified and included in the review. Heterogeneity in study populations was noted including different healthcare settings, definitions for HeFNEF, ejection fraction boundaries, and co-morbidities in included cohorts.
ECG abnormalities reported in patients with HeFNEF include atrial fibrillation (prevalence 12–46%), long PR interval (11–20%), LVH (10–30%), pathological Q waves (11–18%), RBBB (4–16%), LBBB (0–8%) and long JTc (3–4%). Atrial fibrillation and RBBB are more common in patients with HeFNEF compared to those with heart failure and reduced ejection fraction (HeFREF). In contrast, long PR interval, LVH, Q waves, LBBB and long JTc are more common in patients with HeFREF. Pooling of data across five studies showed that QRS duration ≥120 ms, although uncommon (13–19%), is associated with worse outcomes in patients with HeFNEF.
Conclusions: There is high variability in the prevalence of ECG abnormalities in patients with HeFNEF. Atrial fibrillation and RBBB are more common in patients with HeFNEF compared to those with HeFREF. QRS duration ≥120 ms is associated with worse outcomes in patients with HeFNEF. Further studies with systematic documentation of ECG variables are needed to address whether ECG abnormalities correlate with different phenotypes in HeFNEF.