The top left figure displays the distribution of mean lung density for controls (black) and for patients with HFpEF (red). The rightward shift, shorter peak, and wider curve are consistent with increased mean lung density and increased extravascular lung water in patients with HFpEF. Patients with HFpEF also displayed higher extravascular lung water volume (EVLWV, top right) and EVLWV/TLV (bottom left). Cumulative frequency distribution shows higher extravascular lung water as indicated by EVLWV to total lung volume (TLV) ratio in those with HFpEF (bottom right).
Abbreviations: AU = arbitrary units; CT = computed tomography; EVLWV = extravascular lung water volume; EVLWV/TLV = extravascular lung water volume indexed to total lung volume; HFpEF = heart failure with preserved ejection fraction; HU = Hounsfield units