PURPOSE: Screening studies for pulmonary hypertension (PH) in sickle cell disease (SCD) suggest that there is a prevalence of 20% for mild PH (TR >2.5 m/s) and 10 % for moderate PH (TR >3.0 m/s). This mild elevation of the TR jet velocity is associated with an increased risk of death at two years. TR jet velocity is shown to be affected by low hemoglobin, elevated reticulocyte count, and SCD crisis. Significant variability of the TR jet velocity on repeat echocardiograms has been observed. This study aims to examine if patients who have had a normalization of their TR jet velocity on serial echocardiograms still have an increased risk of death at two years.
METHODS: This was a retrospective chart review of patients with SCD. Patient demographics and clinical outcomes were summarized using means, standard deviations. The primary analysis is logistic regression of 2 year mortality against dichotomized TR jet velocity from the first echo. Intra-class correlation coefficient (ICC) was used to evaluate variability in the TR jet velocity and other variables.
RESULTS: 397 SCD charts were reviewed. 209 had no echocardiogram. 113 had no elevation of the TR jet velocity. 20 had TR elevation on a single echocardiogram, and 58 had TR elevation on multiple echocardiograms. 36 of these 58 charts have been fully examined. There was significant variability in the TR jet velocity on serial echocardiograms. ICC for the TR jet velocity was 0.065 and 0.235 for the hemoglobin at the time of echocardiography. There were two deaths, and both had a sustained elevation of the TR jet velocity.
CONCLUSION: Increased TR jet velocity in patients with SCD has been associated with higher risk of mortality; however, a single TR elevation may not be clinically significant. Serial measures over time, at a baseline state of health, may be a more meaningful measure.
CLINICAL IMPLICATIONS: Multiple factors cause transient elevations in TR jet velocity. A single elevation may not be associated with an increased risk of death at two years.
DISCLOSURE: Daniel Gorbett, No Financial Disclosure Information; No Product/Research Disclosure Information