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Sickle cell disease (SCD) is a hemoglobinopathy that affects one in 500 African Americans. Although it is well established that patients with SCD have left ventricular (LV) diastolic dysfunction, it is not clear whether they have subtle LV systolic dysfunction despite preserved ejection fraction (EF). We used three-dimensional speckle tracking echocardiography (3DSTE) to assess changes in both systolic and diastolic LV function in SCD.Transthoracic real time 3D images were obtained (Philips iE33) in 56 subjects, including 28 stable outpatients with SCD (age 33 ± 7 years) and 28 normal controls (age 35 ± 9 years). 3DSTE was performed using prototype software (4DLV Analysis, TomTec) to obtain LV volume and deformation time curves, from which indices of systolic and diastolic LV function were calculated.In SCD patients, 3DSTE-derived LV filling parameters were significantly different from normal controls, reflecting an increase in both rapid and atrial filling volumes and prolonged active relaxation, depicted by a decrease in filling volume fractions at fixed times and an increase in rapid filling duration. Global LV systolic function was not only preserved but increased compared to controls, as reflected by significantly increased global longitudinal strain. Importantly, twist angle and torsion as well as radial and circumferential components of 3D strain were similar in both groups.3DSTE was able to confirm diastolic dysfunction, as expected in some patients with SCD. However, 3DSTE strain analysis did not reveal any changes in LV systolic function. These findings provide novel insight into the pathophysiology of the cardiovascular complications of SCD.

Methods Thirty-one stable, African-American outpatients with SCD (mean age 32±8 yrs) prospectively underwent CMR (Philips 1.5 Tesla) and TTE (Philips iE33). Retrospectivelygated cines of left ventricular (LV) 2-, 3-, and 4-chamber, and short axis cine stack were obtained using SSFP (temporal resolution 25-40ms). Late gadolinium enhancement (LGE) images of the same views were obtained 10-20 minutes after infusion of Gd-DTPA (0.15 mmol/kg) using phase sensitive inversion recovery (TR 4.5 ms, TE 2.2ms, TI 250-300 ms, flip angle 30°, PSIR flip angle 5°). Single short-axis, mid-ventricular myocardial T2* slice and coronal, hepatic T2* slice were acquired with a single breath-hold, at six echo-times (2.3 to 14 msec) using a gradient echo sequence. Tissue T2* signal intensity was measured in LV septum and liver at two separate echo times and T2*= ΔTE/ln (SITE2/ SITE1) where ΔTE represents time difference between the two echo times and ITE1 and ITE2 represent signal intensity at echo time one and two. Myocardial and hepatic T2* were abnormal if