Assante Roberta, Zampella Emilia, Arumugam Parthiban, Acampa Wanda, Imbriaco Massimo, Tout Deborah, Petretta Mario, Tonge Christine, Cuocolo Alberto
Department of Advanced Biomedical Sciences, University Federico II, Via Pansini 5, 80131, Naples, Italy.
Nuclear Medicine Center, Central Manchester University Teaching Hospitals, Manchester, UK.
J Nucl Cardiol. 2017 Apr;24(2):494-501. doi: 10.1007/s12350-015-0359-1. Epub 2016 Jan 15.
We assessed the relationship between coronary artery calcium (CAC) score, myocardial blood flow (MBF) and coronary flow reserve (CFR) in patients undergoing hybrid Rb positron emission tomography (PET)/computed tomography (CT) imaging for suspected CAD. We also evaluated if CAC score is able to predict a reduced CFR independently from conventional coronary risk factors.
A total of 637 (mean age 58 ± 13 years) consecutive patients were studied. CAC score was measured according to the Agatston method and patients were categorized into 4 groups (0, 0.01-99.9, 100-399.9, and ≥400). Baseline and hyperemic MBF were automatically quantified. CFR was calculated as the ratio of hyperemic to baseline MBF and it was considered reduced when <2.
Global CAC score showed a significant inverse correlation with hyperemic MBF and CFR (both P < .001), while no correlation between CAC score and baseline MBF was found. At multivariable logistic regression analysis age, diabetes and CAC score were independently associated with reduced CFR (all P < .001). The addition of CAC score to clinical data increased the global chi-square value for predicting reduced CFR from 81.01 to 91.13 (P < .01). Continuous net reclassification improvement, obtained by adding CAC score to clinical data, was 0.36.
CAC score provides incremental information about coronary vascular function over established CAD risk factors in patients with suspected CAD and it might be helpful for identifying those with a reduced CFR.
我们评估了疑似冠心病患者在接受混合铷正电子发射断层扫描（PET）/计算机断层扫描（CT）成像时冠状动脉钙化（CAC）评分、心肌血流量（MBF）和冠状动脉血流储备（CFR）之间的关系。我们还评估了CAC评分是否能够独立于传统冠状动脉危险因素预测CFR降低。
共研究了637例连续患者（平均年龄58±13岁）。根据阿加斯顿方法测量CAC评分，并将患者分为4组（0、0.01 - 99.9、100 - 399.9和≥400）。自动定量分析静息和充血状态下的MBF。CFR计算为充血状态下与静息状态下MBF的比值，当<2时认为CFR降低。
总体CAC评分与充血状态下的MBF和CFR呈显著负相关（均P < .001），而未发现CAC评分与静息状态下的MBF之间存在相关性。在多变量逻辑回归分析中，年龄、糖尿病和CAC评分与CFR降低独立相关（均P < .001）。将CAC评分加入临床数据后，预测CFR降低的总体卡方值从81.01增加到91.13（P < .01）。通过将CAC评分加入临床数据获得的连续净重新分类改善为0.36。
对于疑似冠心病患者，CAC评分在已有的冠心病危险因素基础上提供了关于冠状动脉血管功能的增量信息，可能有助于识别CFR降低的患者。
