サカイ　アキコ   Sakai Akiko   坂井　晶子    所属   医学部 医学科    職種   講師
言語種別	日本語
発表タイトル	Progression of Fibrosis in Hypoxic Area of Hypertrophic Cardiomyopathy: Demonstration by Cardiac T2* BOLD and T1 Mapping MRI
会議名	第83回日本循環器学会学術集会
主催者	日本循環器学会
学会区分	全国規模の学会
発表形式	口頭
講演区分	一般
発表者・共同発表者	◎安藤聖恵, 萩原誠久, 坂井晶子, 志賀剛, 鈴木敦, 中尾梨沙子, 渡邉絵里, 長尾充展, 石崎海子
発表年月日	2019/03/31
開催地 （都市, 国名）	横浜市
概要	*Oral Presentation (Japanese)32 CT MRI New Technology BACKGROUND: Oxygen-inhalation blood-oxygen-leveldependent (BOLD) T2* cardiac magnetic resonance imaging (T2*-CMR) has been proposed as a new quantification of myocardial oxygenation. Myocardial oxygenation (∆T2*) was defined as the difference in T2* of myocardium between under room-air and oxygen inhalation (∆T2*= T2*oxyT2*air, ms). In refractory heart failure,∆T2* is correlated with oxygen metabolism measured by cardiopulmonary exercise test. We investigated whether myocardial oxygenation derived from T2*-CMR associated with myocardial fibrosis on T1 mapping in patients with hypertrophic cardiomyopathy (HCM). METHOD: Data of T1 mapping and T2*-CMR using 3 tesla MR scanner for 31 patients with HCM was analyzed. T2*-CMR was measured using the black blood and multi-echo gradient-echo sequence. T2* for mid and basal septum of left ventricle was measured under room-air and after 10 minutes inhalation of oxygen at the flow rate of 10 L/min.∆T2* ratio (∆T2* / T2*air, %) was calculated, and the segment with a ∆T2* ratio >10% was defined as hypoxic segment. Native T1 (ms) and extracellular volume fraction (ECV, %) for the same location for T2* measurement were measured on T1 mapping with MOLLI, and were used as estimates of fibrosis. Comparison of native T1 and ECV between segments with and without hypoxia was analyzed by the Mann-Whitney u-test. RESULTS: Fifteen hypoxic segments out of 62 segments (31x2) were observed (24%). Native T1 and ECV were significantly greater for hypoxic segments than non-hypoxic segments (Native T1, 1326±42ms vs. 1286±36ms, p<0.005; ECV, 31.0±3.6% vs. 27.2±4.7%, p<0.005). CONCLUSION: Hybrid analysis of T2*-CMR and T1 mapping reveals the progression of myocardial fibrosis in hypoxic area of HCM.