Radcliffe Department of Medicine, University of Oxford, Oxford, UK.
Department of Cardiology, Oxford University Hospitals NHS Foundation Trust, Oxford, UK.
J Nucl Cardiol. 2019 Oct;26(5):1709-1716. doi: 10.1007/s12350-018-1253-4. Epub 2018 Mar 15.
Using myocardial perfusion scintigraphy (MPS), an increase in left ventricular (LV) volumes or a decrease in ejection fraction (EF) from rest to stress may be clinically important. The variation in these measures between the low-dose stress acquisition and high-dose rest acquisition in a one-day stress-rest protocol has not been established. We assessed the reproducibility of gated volumetric indices between stress and rest and the normal variation in ungated TID ratio for a one-day stress-rest Tc-tetrofosmin protocol.
Two thousand and one hundred and fifty eight (2158) Tc-tetrofosmin MPS patient studies were analyzed retrospectively. Studies were excluded for incomplete data, significant technical difficulties, or (for gated analysis but not for analysis of TID ratio) if the LV EF was > 75%. An analysis of gated data was undertaken to establish the reproducibility of ventricular volumes and EF between stress and rest scans. Ungated volume data were analyzed to determine the confidence limits of TID ratio according to ventricular volume.
Gated data were analyzed for 621 patients without inducible hypoperfusion. Mean EF at rest was slightly higher than after stress (62.4% ± 10.3% vs 61.2% ± 10.4%, P < 0.001), and the standard deviation of the difference was 5.2% (95% CI 4.9% to 5.5%). Ungated volumes were available for 992 non-ischaemic patients. The upper 95% CI for TID ratio was 1.23. This increased from 1.20 to 1.37 between the highest and lowest deciles of rest ungated volume.
Using a one-day stress-rest Tc-tetrofosmin protocol, a fall in LV EF between rest and stress of > 11.6% or a TID ratio of > 1.23 is likely to be clinically reliable. The upper limit of normal for TID ratio needs to be increased for patients with small LV chamber volumes.
使用心肌灌注闪烁显像（MPS），从休息到应激时左心室（LV）容积增加或射血分数（EF）降低可能具有临床意义。在一天的应激-休息方案中，低剂量应激采集与高剂量休息采集之间这些测量值的变化尚未确定。我们评估了门控容积指数在应激和休息之间的可重复性，以及一天的应激-休息 Tc-四氮茂标记物方案中未门控 TID 比值的正常变化。
回顾性分析了 2158 例 Tc-四氮茂 MPS 患者研究。对于数据不完整、存在严重技术困难的研究，或者对于（门控分析，但不适用于 TID 比值分析）如果 LV EF>75%，则排除这些研究。进行门控数据分析以确定心室容积和 EF 在应激和休息扫描之间的可重复性。分析非门控容积数据，以根据心室容积确定 TID 比值的置信限。
对 621 例无可诱导灌注不足的患者进行了门控数据分析。休息时的平均 EF 略高于应激后（62.4%±10.3%对 61.2%±10.4%，P<0.001），差异的标准差为 5.2%（95%置信区间 4.9%至 5.5%）。992 例非缺血患者可获得非门控容积。TID 比值的上限 95%置信区间为 1.23。这一数值在休息时非门控容积最高和最低十分位数之间从 1.20 增加到 1.37。
使用一天的应激-休息 Tc-四氮茂标记物方案，如果 LV EF 从休息到应激下降>11.6%或 TID 比值>1.23，则可能具有临床可靠性。对于 LV 腔室容积较小的患者，需要增加 TID 比值的正常上限。
