所属 医学部 医学科（東京女子医科大学病院） 職種 助教
|発表タイトル||Progression of Fibrosis in Hypoxic Area of Hypertrophic Cardiomyopathy: Demonstration by Cardiac T2* BOLD and T1 Mapping MRI|
|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|
|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.