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的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 中心，但不一定是研究者所在的机构。 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患者与不接受输血的患者的肺动脉高压程度;如果输血患者的肺动脉高压明显降低，则表明输血具有保护作用。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，以观察输血是否会急剧改变肺部的血压。除了观察肺血压，我们还将检查心脏的收缩和舒张、心率变异性（心脏健康的间接标志）、血管舒张、心脏泵送的血液量、血氧和红细胞的完整性，因为这些变量都与肺血压的变化有关。 具体目标1：确定一组接受长期输血治疗的镰状细胞性贫血患者肺动脉高压和内皮功能障碍的患病率。 具体目标二：在接受长期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子。 具体目标3：确定输血治疗对TR喷射速度、溶血、缺氧、心脏舒张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.