Background:Coronary artery calcification is a marker of underlying atherosclerotic vascular disease. The absence of coronary artery calcification is associated with a low prevalence of obstructive coronary artery disease (CAD), but it cannot be ruled out completely. We sought to develop a clinical tool that can be added to Agatston score of zero to rule out obstructive CAD with high accuracy.Methods:We developed a clinical score retrospectively from a cohort of 4903 consecutive patients with an Agatston score of zero. Patients with prior diagnosis of CAD, coronary percutaneous coronary intervention, or surgical revascularization were excluded. Obstructive CAD was defined as any epicardial vessel diameter narrowing of ≥50%. The score was validated using an external cohort of 4290 patients with an Agatston score of zero from a multinational registry.Results:The score consisted of 7 variables: age, sex, typical chest pain, dyslipidemia, hypertension, family history, and diabetes mellitus. The model was robust with an area under the curve of 0.70 (95% CI, 0.65–0.76) in the derivation cohort and 0.69 (95% CI, 0.65–0.72) in the validation cohort. Patients were divided into 3 risk groups based on the score: low (≤6), intermediate (7–13), and high (≥14). Patients who score ≤6 have a negative likelihood ratio of 0.42 for obstructive CAD, whereas those who score ≥14 have a positive likelihood ratio of >5.5 for obstructive CAD. The outcome was ruled out in >98% of patients with a score ≤6 in the validation cohort.Conclusions:We developed a score that may be used to identify the likelihood of obstructive CAD in patients with an Agatston score of zero, which may be used to direct the need for additional testing. However, the results of this retrospective analysis are hypothesis generating and before clinical implementation should be validated in a trial with a prospectively collected data.

中文翻译：

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即时医疗点临床风险评分，以提高Agatston评分零的阴性诊断效用：避免了冠状动脉计算机断层扫描血管造影的需要。

背景：冠状动脉钙化是潜在的动脉粥样硬化性血管疾病的标志。冠状动脉钙化的缺乏与阻塞性冠状动脉疾病（CAD）的患病率低有关，但不能完全排除。我们试图开发一种可以添加到Agatston评分为零的临床工具，以高精度排除阻塞性CAD。方法：我们回顾性研究了来自4903名连续的Agatston评分为零的患者的临床评分。排除事先诊断为CAD，冠状动脉经皮冠状动脉介入治疗或外科血运重建的患者。阻塞性CAD定义为任何心外膜血管直径缩小≥50％。这项评分是由来自外部注册机构的4290名患者的Agatston评分为零的外部队列进行验证的。结果：该分数包括7个变量：年龄，性别，典型的胸痛，血脂异常，高血压，家族史和糖尿病。该模型具有鲁棒性，在衍生队列中的曲线下面积为0.70（95％CI，0.65-0.76），在验证队列中的面积为0.69（95％CI，0.65-0.72）。根据评分将患者分为3个风险组：低（≤6），中（7-13）和高（≥14）。得分≤6的患者阻塞性CAD的阴性可能性比为0.42，而得分≥14的患者阻塞性CAD的阳性可能性比值为> 5.5。在验证队列中，> 98％得分≤6的患者排除了结局。结论：我们开发了一个得分，可用于识别Agatston得分为零的患者发生阻塞性CAD的可能性，可以用来指示需要进行其他测试。但是，这种回顾性分析的结果是产生假设的，并且在临床应用中应使用前瞻性收集的数据验证其有效性。