It is known that a minority (around 30%) of patients who are referred by their GP because of suspected HF based on medical history, symptoms, and signs actually have HF.2,14 Conditions other than HF but related to shortness of breath may also result in NTproBNP levels above 125 pg/ml; for example, atrial fibrillation, renal dysfunction, left ventricular hypertrophy, and age >75 years.3 Here, NPPB is linked to Abnormal renal physiology.