Summary: | Sickle cell disease (SCD) is one of the most prevalent genetic disorders worldwide that affects approximately 12,000 people in the United Kingdom. Raised tricuspid regurgitant velocity (TRV), which may be related to left ventricular diastolic dysfunction (LV DD), occurs in approximately 30% of adults with SCD, and has been shown to be an independent risk factor for death. This thesis examines aspects of the role of LV DD in the development of increased tricuspid regurgitant velocity and investigates the hypothesis that myocardial dysfunction, affecting the right and left ventricle, is an important cardiovascular risk factor in patients with SCD. In the retrospective study, we determine the 5 year- survival of a cohort of patients with SCD based on their TRV. The association between raised TRV and mortality in a UK SCD population has been confirmed. Higher values of TRV were associated with a greater than 4 fold increased risk of death (HR: 4.48, 99%CI 1.01-19.8). In the prospective study, sixty-one patients with SCD were included in the study (mean duration of follow-up 17.13±3 months). In the serial echocardiographic study, left ventricular average E/E' ratio which is a predictor of increased left ventricular filling pressures, was independently associated with an increased tricuspid regurgitation velocity (p=0.007). In addition, blood urea nitrogen and global function index lateral showed independent association with an increased LV lateral E/E' ratio. Biventricular myocardial deformation by 2D and 3D speckle tracking revealed significant changes in the serial measurements of systolic function. These findings provide novel insight into the pathophysiology of the cardiovascular complications of SCD and support the implementation of echocardiographic screening of adult patients with SCD to identify high-risk individuals for further evaluation.
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