Height, weight, gender, saturation, heart failure classification (Ross or NYHA), medications, the electrocardiogram, echocardiography, pro BNP, and sST2 values of the patients, as well as any hospitalization, lower respiratory tract infection, organ dysfunction, or need for angiography or surgery during follow-up data on arrhythmia and death were gathered during a 1-year follow-up. Here, NPPB is linked to heart failure.