Background:Sequential assessment using CT coronary angiography (coronary CT) and nuclear myocardial perfusion imaging (MPI) is considered an anatomical and functional evaluation of coronary artery disease (CAD). However, there can be unexpected radiation exposure. Hybrid MPI with stress-only nuclear MPI and rest CT-MPI using coronary CT may contribute to reducing the radiation dose in sequential assessment with nuclear MPI after coronary CT. We analyzed the diagnostic performance and total radiation dose of hybrid MPI for detection of significant CAD compared with sequential assessment using nuclear MPI after coronary CT.

Methods and Results:The results for 101 patients who underwent coronary CT, nuclear MPI and invasive coronary angiography within 3 months of all imaging were analyzed. We calculated the summed difference score (SDS) from standard nuclear MPI and hybrid SDS from hybrid MPI, which revealed myocardial ischemia. The diagnostic performance of SDS and hybrid SDS for detecting significant CAD was analyzed using receiver-operating characteristic (ROC) curve analysis. We also compared the total radiation dose of both methods. The area under the ROC curve was not different between SDS and hybrid SDS (0.901 and 0.815, P=0.079). Total radiation dose of hybrid MPI was significantly lower than standard nuclear MPI with CT angiography (4.62 mSv vs. 9.72 mSv, P<0.0001).

Conclusions:Hybrid MPI showed a precise diagnostic accuracy for significant CAD detection.

背景：使用CT冠状动脉造影（冠状动脉CT）和核心肌灌注成像（MPI）进行的顺序评估被认为是冠状动脉疾病（CAD）的解剖学和功能评估。但是，可能会有意外的辐射暴露。冠状动脉CT后仅接受核MPI和使用冠状动脉CT的其余CT-MPI的混合MPI可能有助于减少放射剂量。我们分析了混合MPI的诊断性能和总放射剂量，以检测冠状动脉CT后与使用核MPI进行的连续评估相比，检测出显着的CAD。

方法和结果：分析了101例在所有影像学检查后3个月内接受冠状动脉CT，核MPI和有创冠状动脉造影的患者的结果。我们计算了标准核MPI的总和差异分数（SDS）和混合MPI的混合SDS，揭示了心肌缺血。使用接收器工作特性（ROC）曲线分析分析了SDS和混合SDS对检测重要CAD的诊断性能。我们还比较了两种方法的总辐射剂量。SDS和混合SDS的ROC曲线下面积无差异（0.901和0.815，P = 0.079）。混合MPI的总放射剂量显着低于使用CT血管造影的标准核MPI（4.62 mSv对9.72 mSv，P <0.0001）。

结论：混合MPI对重要的CAD检测显示出精确的诊断准确性。