Cerebral Blood Flow in Single Ventricle and Normal Children Utilizing MRI

项目概要/摘要： 出生时心脏只有一个可用的泵室（单心室）的儿童， 在美国先天性心脏病（CHD）发病率和死亡率的主要原因。的 最常见的修复是改良的Fontan手术，其中心脏的右侧被旁路， 血液被直接引导到肺而没有泵送室。这种手术是分阶段进行的。在 手术初期，建立从主动脉到肺动脉和心脏流出的连接 重建（第一阶段）。在中间阶段，来自上级腔静脉的流动被直接引导到 下腔静脉血流直接进入单心室。丰唐 完成包括通过挡板或导管将下腔静脉血液引导到肺动脉。 单心室患者也被称为有更大的神经问题比一般 人群和其他形式的CHD。一个影响因素是脑血流量（CBF）;证据来自 我们实验室的初步数据以及已发表的文献表明，CBF的量与 到智力。有理由相信单心室患者的CBF不同于正常人 儿童和整个分期手术重建的变化。在第一阶段， 主动脉和肺动脉降低血压并将血液吸入肺部。在第二阶段， 大脑和肺直接相互串联连接，并且只相互连接（血液从 主动脉到脑，然后直接进入上级腔静脉到肺）。最后，在完成丰唐 脑静脉压升高在这些阶段的CBF量仍然未知 沿着脑血流量的变化，二氧化碳增加，增加脑血流量，是 大脑适应血液流动的能力事实上，没有关于正常儿童CBF的数据 在文学作品中。这在这个年龄段尤其重要，因为大脑发育的这个快速增长阶段可能 与最终的神经功能有关。阐明单心室CBF可能最终导致改变 在这些患者的管理中;如果一个阶段对CBF有不利影响，例如，不正常， 提前完成Fontan而不是典型的18个月时间表可能是谨慎的。 通过准确测量CBF，我们的实验室以前做过，磁共振成像（MRI） 提供了一个独特的机会来测量CBF非侵入性，CBF对二氧化碳的反应，以及大脑 体积和异常。了解单心室CBF随手术阶段的变化， 与正常儿童相比，可能会导致理解为什么他们有神经问题， 改变医疗或手术管理。这是一项前瞻性、非随机、单中心研究， 通过MRI对单心室患者和其他形式CHD的CBF的初步数据，并试图确定 单心室分期手术中脑血流变化与正常儿童比较

Project Summary/Abstract: Children who are born with a heart containing only one usable pumping chamber (single ventricle) are the leading cause of morbidity and mortality from congenital heart disease (CHD) in the United States. The most common repair is the modified Fontan operation in which the right side of the heart is bypassed and blood is channeled directly to the lungs without a pumping chamber. This surgery is performed in stages. In the initial operation, a connection is created from the aorta to the pulmonary arteries and the outflow from the heart is reconstructed (Stage I). In an intermediate stage, flow from the superior vena cava is channeled directly into the pulmonary arteries while the inferior vena caval flow enters the single ventricle directly. The Fontan completion involves routing inferior vena caval blood to the pulmonary arteries via a baffle or conduit. Patients with single ventricle are also known to have greater neurological problems than the general population and other forms of CHD. One contributing factor is cerebral blood flow (CBF); evidence from preliminary data from our lab as well as in the published literature suggests that the amount of CBF is related to intelligence. There are reasons to believe that CBF in single ventricle patients is different from normal children and changes throughout staged surgical reconstruction. At Stage I, the connection created between the aorta and pulmonary arteries decrease blood pressure and suck blood into the lungs. In the second stage, the brain and lungs are hooked up directly in series with each other and only with each other (blood flows from the aorta to the brain and then directly into the superior vena cava to the lungs). Finally, after complete Fontan reconstruction, brain venous pressures are elevated. The amount of CBF during these stages remain unknown along with the change in CBF with increased carbon dioxide which increases brain flow and is a marker for how well the brain can adapt to meet its blood flow needs. Indeed, there is no data on CBF in normal children in the literature. This is especially important at this age since this rapid growth stage of brain development may be related to ultimate neurological function. Elucidating CBF in single ventricles may ultimately lead to changes in management of these patients; if one stage has an adverse effect on CBF for example and is not normal, it might be prudent to complete the Fontan earlier rather than the typical 18 month timeframe. By accurately measuring CBF which our lab has done previously, magnetic resonance imaging (MRI) offers a unique opportunity to measure CBF non-invasively, CBF response to carbon dioxide as well as brain volumes and abnormalities. Understanding how CBF changes in single ventricles with the stage of surgery as compared to normal children may lead to understanding why they have neurological problems and possibly change medical or surgical management. This is a prospective, non-randomized, single center study built upon preliminary data on CBF in single ventricle patients and other forms of CHD via MRI and seeks to determine CBF changes in single ventricles during staged surgical reconstruction as compared with normal children.