PULM HYPERTENSION AND CHRONIC TRANSFUSION THERAPY IN PATIENTS W/ SICKLE CELL

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 肺动脉高压(肺部高血压)是镰状细胞病(SCD)患者的主要杀手。定期输血可以改善SCD的许多方面，但尚不清楚它们是否有助于预防肺动脉高压。我们将从两个方面来研究这个问题。首先，我们将比较定期输血的SCD患者和没有接受输血的患者的肺动脉高压程度；如果输血的患者的肺动脉高压明显较轻，这表明输血是有保护作用的。其次，我们将在输血前和输血后72小时检查长期输血的SCD患者，看看输血是否会显著改变肺部的血压。除了观察肺血压，我们还将检查心脏的收缩和松弛、心率变异性(心脏健康的间接标志)、血管松弛、心脏泵送的血量、血液氧合和红细胞的完整性，因为这些变量都与肺血压的变化有关。 具体目的1：确定一组接受慢性输血治疗的镰状细胞性贫血患者的肺动脉高压和内皮功能障碍的患病率。 具体目标2：在接受慢性输血治疗的镰状细胞性贫血患者亚组中，确定肺动脉高压和内皮功能障碍的预测因素。 具体目标3：确定输液治疗对心脏血流速度、溶血、缺氧、心脏舒张期功能和内皮功能的急性影响。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Pulmonary hypertension (high blood pressure in the lungs) is a leading killer in patients with sickle cell disease (SCD). Regular blood transfusions improve many aspects of SCD but it is not known whether they help prevent pulmonary hypertension. We will examine this question two ways. First, we will compare the degree of pulmonary hypertension in regularly transfused patients with SCD to those who do not receive transfusions; if the transfused patients have significant less pulmonary hypertension it suggests that transfusions are protective. Secondly, we will examine chronically transfused SCD patients before and 72 hours after having a blood transfusion to see if the transfusion acutely changes the blood pressure in the lungs. In addition to looking at lung blood pressure, we will examine the contraction and relaxation of the heart, heart rate variability (an indirect sign of heart health), blood vessel relaxation, volume of blood pumped by the heart, blood oxygenation, and the integrity of the red blood cells as these variables are all associated with changes in lung blood pressure. Specific Aim 1: Determine the prevalence of pulmonary hypertension and endothelial dysfunction in a group of patients with sickle cell anemia on chronic transfusion therapy. Specific Aim 2: Identify predictors of pulmonary hypertension and endothelial dysfunction in the subgroup of patients with sickle cell anemia on chronic transfusion therapy. Specific Aim 3: Identify acute effects of transfusion therapy on TR jet velocity, hemolysis, hypoxia, cardiac diastolic function, and endothelial function.