NPPB and Abnormal renal physiology: Moreover, levels of plasma NPs, particularly B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP), are routinely used for the diagnosis and prognosis of HF [23]; however, their diagnostic accuracy is limited in certain clinical contexts—especially in HFpEF—and their circulating levels can be influenced by non-cardiac factors such as renal dysfunction, obesity, and advanced age [24,25,26].