Recent data show that pulmonary hypertension (PH), defined by a tricuspid regurgitation jet (TRJ) velocity > or equal at 2.5m/s on Doppler echocardiography, is present in about 30% of adults with sickle cell disease (SCD) and is associated with poor prognosis. However in SCD the occurrence of PH (defined by mean pulmonary arterial pressure (mPAP)> or equal at 25 mmHg) is related to at least 3 mechanisms: PH due to hyperkinetic state with high cardiac output (CO) but normal pulmonary vascular resistance (PVR <160 dynes), or postcapillary PH (pulmonary capillary wedge pressure PCWP >15 mmHg), or precapillary pulmonary arterial hypertension (PAH) defined by mPAP > or equal at 25 mmHg, PCWP< or equal at 15 mmHg and PVR > or equal at 160 dynes.The aim of this study is to evaluate in a French population of adults with sickle cell disease the characteristics, prevalence and prognosis of pulmonary hypertension.