NPPB and Obesity: In this study, PAWP was higher for any given NT-proBNP level in patients with obesity-related HFpEF compared to non-obese HFpEF patients; however, the relationship between NT-proBNP and LV transmural pressure, defined as intracavitary pressure (PAWP) minus the external pressure applied to the LV from pericardium and the right side of the heart (RA pressure), did not change in both obese and non-obese patients with HFpEF (32).