LV diastolic dysfunction promotes PH development in SCD. LV diastolic dysfunction, which is increased LV pressure in the presence of normal LV volume (EDPVR), promotes stiffening of the LH and decreased myocardial relaxation (stretch). Less LV relaxation impairs LV filling and LA pressure rises, producing an afterload on the PV circulation. Pulmonary (Pulm) hydrostatic pressure builds, causing oedema to form in the lungs which exerts a back pressure on the PA. High PA pressure develops, giving rise to PH. EDPVR, end diastolic pressure volume relationship; LA, left atrial; LH, left heart; LV, left ventricle; PA, pulmonary artery; PH, pulmonary hypertension; PV, pulmonary venous; TRV, tricuspid regurgitant jet velocity; RVSP, right ventricular systolic pressure; SCD, sickle cell disease.