心電図同期心筋SPECTと心臓MRIから算出される心機能解析値の評価

摘要

It is stated that cardiac MRI imaging can provide accurate estimation of left ventricular (LV) volumes and ejection fraction (EF). The purpose of this study was to evaluate the accuracy of gated myocardial perfusion SPECT for assessment of LV end-diastolic volume (EDV), end-systolic volume (ESV) and EF, using cardiac MRI as the reference methods/(methodology). Gated myocardial perfusion SPECT images were analyzed with two different quantification software, QGS and 4D-MSPECT. Thirty-four consecutive patients were studied. Myocardial perfusion SPECT and cardiac MRI had excellent intra/interobserver reproducibil-ity. Correlation between the results of gated myocardial perfusion SPECT and cardiac MRI were high for EDV and EF. However; ESV and EDV were significantly underestimated by gated myocardial perfusion SPECT compared to cardiac MRI. Moreover; gated myocardial perfusion SPECT overestimated EF for small heart. One reason for the difference in volumes and EF is the delineation of the endocardial border. Cardiac MRI has higher spatial resolution. We should understand the differences of volumes and EF as determined by gated myocardial perfusion SPECT and cardiac MRI.%心筋血流と壁運動を同時に評価可能な心電図同期 心筋singlephoton emission computed tomography （SPECT）法は，現在標準的な心筋血流検査法として 利用されており，心電図同期心筋SPECT検査の有用 性と，算出された心機能解析値のエビデンスレベル は高く評価されている1・2）．心電図同期心筋SPECTを 用いた心機能解析プログラムとして，完全な自動処 理または半自動処理など各種解析ソフトウェアが考 案され臨床使用されており，quantitative gated SPECT（QGS）は最も広く利用されているソフトウェア の一つである3，4）．