Dr Januzzi: Different cut-offs for preserved ejection fraction (HFpEF) are not recommended. However, it is recognised that preserved EF heart failure may be more likely to be below the rule in the threshold. 300 pg/mL is the rule out level and then from 300 pg/mL up to 1800 pg/mL is a grey zone. Patients with preserved EF heart failure may be more likely to be in the grey zone, and there is nothing normal about being in that range. So, if you see a patient in the grey zone, the diagnosis is still very likely to be heart failure. You really need to be at the bedside and do a good history and physical to help interpret the value.
