Department of Cardiovascular Medicine, Yao Municipal Hospital, 1-3-1 Ryuge-cho, Yao, Osaka, 581-0069, Japan.
BMC Cardiovasc Disord. 2020 Oct 7;20(1):438. doi: 10.1186/s12872-020-01720-w.
Myocardial perfusion single-photon emission computed tomography (SPECT) imaging with stress is a useful examination for detecting coronary artery disease. Since the presence of artifacts is remaining challenges, we aimed to define the minimum intensity of low-grade exercise stress levels combined with drug stress to reduce undesired artifacts and their related factors.
We divided patients with suspicious coronary artery disease into 4 groups as follows: group A, adenosine triphosphate (ATP) for 6 min; group A + 25 W, ATP + 25 W exercise for 6 min; group A + 35 W, ATP + 35 W exercise for 6 min; group A + 45 W, ATP + 45 W exercise for 6 min) and enrolled only those whose summed stress scores were < 3. Undesired artifacts were evaluated on the basis of heart-to-liver activity (H/L) ratio and heart-to-10 pixels below the heart (H/below the H) ratio.
The logarithmic values of H/L and H/below the H ratios were significantly higher in groups A + 35 W and A + 45 W than in group A (p < 0.05, each). In all the patients, the logarithmic values of H/L and H/below the H ratios positively correlated with the increment of rate pressure product (RPP, p = 0.002 and p = 0.005, respectively) after stress in the univariate analysis. The left ventricular end-diastolic volume (LVEDV) after stress (p = 0.002) negatively correlated with the logarithmic value of H/below the H ratio, but not H/L ratio. Although the increment of RPP was independently associated with the logarithmic values of both H/L (p = 0.001) and H/below the H ratios (p = 0.005), LVEDV was also independently associated with the logarithmic value of H/below the H ratio (p < 0.001) in multivariate regression analysis under adjusting with age and sex.
ATP plus ≥35 W exercise stress for 6 min was useful for reducing undesired artifacts after stress in myocardial perfusion SPECT. LVEDV after stress in addition to the increment of RPP was independently associated with the H/below the H ratio, but not the H/L ratio.
负荷心肌灌注单光子发射计算机断层（SPECT）成像检查是一种用于检测冠状动脉疾病的有用方法。由于存在伪影仍然是一个挑战，我们的目的是确定低水平运动应激水平与药物应激相结合的最低强度，以减少不必要的伪影及其相关因素。
我们将可疑冠心病患者分为 4 组：A 组，三磷酸腺苷（ATP）6 分钟；A+25W 组，ATP+25W 运动 6 分钟；A+35W 组，ATP+35W 运动 6 分钟；A+45W 组，ATP+45W 运动 6 分钟），仅纳入总应激评分<3 的患者。根据心-肝活性（H/L）比和心-心下 10 像素（H/below the H）比评估不必要的伪影。
A+35W 和 A+45W 组的 H/L 和 H/below the H 比值的对数均显著高于 A 组（p<0.05，每组）。在所有患者中，应激后 RPP 增量与 H/L 和 H/below the H 比值的对数呈正相关（p=0.002 和 p=0.005）。在单变量分析中，应激后左心室舒张末期容积（LVEDV）与 H/below the H 比值的对数呈负相关（p=0.002），但与 H/L 比值无关。虽然 RPP 的增量与 H/L（p=0.001）和 H/below the H 比值的对数均独立相关（p=0.005），但在调整年龄和性别后，LVEDV 也与 H/below the H 比值的对数独立相关（p<0.001）。
ATP 加≥35W 运动应激 6 分钟有助于减少心肌灌注 SPECT 应激后的不必要伪影。应激后 LVEDV 除了 RPP 的增量外，与 H/below the H 比值独立相关，而与 H/L 比值无关。
