Free Paper Oral 9 (I-OR09)

[I-OR09-04] Novel Mechanisms for Cerebral Blood Flow Regulation in Patients with Congenital Heart Disease

^○齋木 宏文, 杉本 昌也, 桑田 聖子, 栗嶋 クララ, 岩本 洋一, 石戸 博隆, 増谷 聡, 先崎 秀明 (埼玉医科大学 総合医療センター 小児循環器科)

Keywords:brain, congenital heart, regulation

BACKGROUND: The mechanisms to regulate cerebral flow in repaired congenital heart diseases (CHDs) remain poorly understood. We tested hypothesis that postoperative pts with CHD have hemodynamic specific compensatory mechanisms for maintaining cerebral perfusion.METHODS: A total of 89 pts with specific hemodynamics including Glenn (n = 14), Fontan (n = 19), repaired tetralogy of Fallot (TOF; n = 24), and control pts (n = 32) were enrolled. The resistance and blood flow distribution between the brain (Rc, CIc) and lower body (Rs, CIs) were calculated by measuring the hemodynamic changes resulting from inferior vena cava occlusion.RESULTS: Despite considerable differences in cardiac index (CI) and superior vena cava pressure (SVCp), cerebral flow was preserved in all non-control groups, with a ratio between the vascular resistances in the cerebral and lower body circulation (Rc/Rs) that was significantly lower than that in controls. Interestingly, the reduced Rc/Rs of Glenn patients was mediated by the reduced Rc, whereas augmented Rs prompted to the reduced Rc/Rs in the Fontan and TOF groups. Multivariate analysis revealed high SVCp was significantly associated with low Rc. Although low CI was significantly associated with increased Rc and Rs, its impact was much greater on Rs than on Rc.CONCLUSIONS: Compensatory mechanisms for cerebral flow regulation depends on hemodynamics. Such regulation mechanisms implies cerebral circulation fragility, emphasizing desperate need for investigations to address the impacts of cerebral circulation properties on neurodevelopmental outcomes.