Ababneh A A, Sciacca R R, Kim B, Bergmann S R
Department of Medicine, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA.
J Nucl Cardiol. 2000 Nov-Dec;7(6):661-8. doi: 10.1067/mnc.2000.109861.
Myocardial imaging with tracers such as technetium-99m sestamibi or thallium-201 is extensively used as a means of measuring myocardial perfusion. With gated acquisition, these tracers can also be used as a means of measuring left ventricular ejection fraction (EF) and end diastolic and end systolic volumes (EDV and ESV, respectively). The objective of this study was to determine the normal range of EF, EDV, and ESV and to evaluate differences caused by either the tracer used, the gender of the patient, or the acquisition camera used.
A total of 1513 consecutive patients (mean age, 60+/-12 years [SD]) who had normal results on Bruce exercise tests had either Tc-99m sestamibi (n = 884) or Tl-201 (n = 629) injected at peak stress. Although all patients were referred for the evaluation of chest pain or dyspnea and many had cardiac risk factors, all had normal exercise capacity corrected for age, no electrocardiographic signs of ischemia, normal results on perfusion scans, and normal wall motion determined by means of quantitated gated single photon emission computed tomography (QGS). Scans were acquired on 1 of 3 different cameras. The mean EF for all patients who had gated Tc-99m sestamibi scans was 63% +/- 9%, not different from patients who had gated Tl-201 scans (63% +/- 9%). However, when the gender of the patient was considered, the mean EF for women was 66% +/- 8% with Tc-99m sestamibi (n = 519), higher than the mean EF for men (58% +/- 8%, n = 365, P<.0001). Similarly, the mean EF for women studied with Tl-201 (67% +/- 8%, n = 326) was higher than that of men (59% +/- 7%, n = 303,P<.0001). Patients with diabetes mellitus (n = 153) had a slightly reduced EF (62% +/- 10%, P<.001). In a subset of 240 patients, 140 patients studied with Tc-99m sestamibi and 100 studied with Tl-201, the EDV and ESV for women (n = 124) was estimated by means of QGS to be lower (57 +/- 17 mL and 19 +/- 11 mL, respectively) than those for men (74 +/- 22 mL-and 29 +/- 13 mL, respectively; n = 116; P<.001 for each comparison). No clinically significant differences in EF or volumes were noted based on tracers used or acquisition camera. For patients with normal results on exercise treadmill tests and perfusion imaging, the lower limit of normal for EF with gated perfusion imaging with QGS was 50% for women and 43% for men. For EDV and ESV, the upper limit of normal was 91 mL and 40 mL, respectively, for women and 119 mL and 55 mL, respectively, for men.
No significant differences related to either tracer or acquisition camera used were noted for EF, suggesting equivalency for clinical trials for patients with normal results on exercise tests. However, EF, EDV, and ESV determined by means of gated perfusion imaging need to be corrected for gender.
使用锝-99m 甲氧基异丁基异腈或铊-201 等示踪剂进行心肌成像被广泛用作测量心肌灌注的手段。通过门控采集，这些示踪剂还可用于测量左心室射血分数（EF）以及舒张末期和收缩末期容积（分别为 EDV 和 ESV）。本研究的目的是确定 EF、EDV 和 ESV 的正常范围，并评估所用示踪剂、患者性别或所用采集相机所导致的差异。
共有 1513 例连续患者（平均年龄 60±12 岁[标准差]），其布鲁斯运动试验结果正常，在运动高峰时注射了锝-99m 甲氧基异丁基异腈（n = 884）或铊-201（n = 629）。尽管所有患者均因胸痛或呼吸困难而就诊，且许多患者有心脏危险因素，但所有患者的年龄校正运动能力正常、无缺血性心电图表现、灌注扫描结果正常且通过定量门控单光子发射计算机断层扫描（QGS）确定的室壁运动正常。扫描在 3 种不同相机中的 1 种上进行。所有进行门控锝-99m 甲氧基异丁基异腈扫描的患者的平均 EF 为 63%±9%，与进行门控铊-201 扫描的患者（63%±9%）无差异。然而，考虑患者性别时，使用锝-99m 甲氧基异丁基异腈的女性患者平均 EF 为 66%±8%（n = 519），高于男性患者的平均 EF（58%±8%，n = 365，P<0.0001）。同样，使用铊-201 研究的女性患者平均 EF（67%±8%，n = 326）高于男性患者（59%±7%，n = 303，P<0.0001）。糖尿病患者（n = 153）的 EF 略有降低（62%±10%，P<0.001）。在 240 例患者的亚组中，140 例使用锝-99m 甲氧基异丁基异腈进行研究，100 例使用铊-201 进行研究，通过 QGS 估计女性患者（n = 124）的 EDV 和 ESV 低于男性患者（分别为 57±17 mL 和 19±11 mL，而男性患者分别为 74±22 mL 和 29±13 mL；n = 116；每次比较 P<0.001）。基于所用示踪剂或采集相机，未发现 EF 或容积有临床显著差异。对于运动平板试验和灌注成像结果正常的患者，使用 QGS 进行门控灌注成像时，EF 的正常下限女性为 50%，男性为 43%。对于 EDV 和 ESV，正常上限女性分别为 91 mL 和 40 mL，男性分别为 119 mL 和 55 mL。
对于 EF，未发现与所用示踪剂或采集相机相关的显著差异，这表明对于运动试验结果正常的患者，在临床试验中二者等效。然而，通过门控灌注成像确定的 EF、EDV 和 ESV 需要根据性别进行校正。
