Chua T, Yin L C, Thiang T H, Choo T B, Ping D Z, Leng L Y
Department of Cardiology, National Heart Centre, Mistri Wing, Singapore.
J Nucl Cardiol. 2000 Jul-Aug;7(4):301-11. doi: 10.1067/mnc.2000.105279.
Gated single photon emission computed tomography (SPECT) with automated methods allows the quantitative assessment of left ventricular function and perfusion; however, its accuracy must be defined for patients with large earlier infarctions and severe rest perfusion defects, in whom the estimation of endocardial and epicardial borders might be more difficult, even with automated edge-detection techniques.
We prospectively compared the automated measurements of left ventricular ejection fraction (LVEF) and volumes from rest-injected gated Technetium 99m (Tc99m) perfusion SPECT with equilibrium radionuclide angiocardiography (ERNA) in 62 patients and the assessment of regional function with echocardiography in 22 patients. Forty-six patients had an earlier myocardial infarction (mean defect size, 34% of left ventricle; SD, 12.7%; range, 8% to 56%); 27 patients had large defects (> or = 20% of left ventricle; LVEF range, 8% to 75%). LVEF, as determined with Cedars-Sinai software (quantitative gated SPECT), correlated well with ERNA (r = 0.941; y = 1.003x + 1.15; P<.0001; SE of the estimate = 6.3%; mean difference -1.3% for LVEF) in the entire study population and in the subgroups of patients with an earlier infarction, severe defects, and large infarctions (> or = 20% of the left ventricle). A correlation existed between gated SPECT and ERNA volumes (r = 0.882, y = 1.040x - 14.7, P<.0001 for end-diastolic volume; r = 0.954, y = 1.147x - 13.9, P<.0001 for end-systolic volumes with the count-ratio technique), but with wider limits of agreement. The exact segmental score agreement between gated SPECT and echocardiography for regional function was 79.8% (281 of 352, kappa = 0.682).
Automated gated SPECT provides an accurate assessment of ejection fraction and regional function, even in the presence of an earlier myocardial infarction with large perfusion defects and significant left ventricular dysfunction.
采用自动化方法的门控单光子发射计算机断层扫描（SPECT）可对左心室功能和灌注进行定量评估；然而，对于早期梗死面积大且静息灌注缺损严重的患者，即使采用自动化边缘检测技术，心内膜和心外膜边界的估计可能也会更困难，因此必须确定其准确性。
我们前瞻性地比较了62例患者静息注射门控锝99m（Tc99m）灌注SPECT自动测量的左心室射血分数（LVEF）和容积与平衡放射性核素血管造影（ERNA）的结果，并比较了22例患者超声心动图评估的局部功能。46例患者有早期心肌梗死（平均缺损面积，占左心室的34%；标准差，12.7%；范围，8%至56%）；27例患者有大面积缺损（≥左心室的20%；LVEF范围，8%至75%）。使用雪松西奈软件（定量门控SPECT）测定的LVEF与ERNA相关性良好（r = 0.941；y = 1.003x + 1.15；P <.0001；估计标准误 = 6.3%；LVEF平均差异 -1.3%），在整个研究人群以及有早期梗死、严重缺损和大面积梗死（≥左心室的20%）的患者亚组中均如此。门控SPECT与ERNA容积之间存在相关性（舒张末期容积：r = 0.882，y = 1.040x - 14.7，P <.0001；收缩末期容积采用计数比技术：r = 0.954，y = 1.147x - 13.9，P <.0001），但一致性界限更宽。门控SPECT与超声心动图对局部功能的精确节段评分一致性为79.8%（352个节段中的281个，kappa = 0.682）。
即使存在早期心肌梗死伴大面积灌注缺损和明显左心室功能障碍，自动化门控SPECT仍能准确评估射血分数和局部功能。
