Chaikriangkrai Kongkiat, Palamaner Subash Shantha Ghanshyam, Jhun Hye Yeon, Ungprasert Patompong, Sigurdsson Gardar, Nabi Faisal, Mahmarian John J, Chang Su Min
Heart and Vascular Center, University of Iowa Hospital, Iowa City, IA.
Department of Medicine, University of Kansas Medical Center, Kansas City, KS.
Ann Emerg Med. 2016 Dec;68(6):659-670. doi: 10.1016/j.annemergmed.2016.07.020. Epub 2016 Oct 17.
Coronary artery calcium score (CACS) is a well-established test for risk stratifying asymptomatic patients. Recent studies also indicate that CACS may accurately risk stratify stable patients presenting to the emergency department (ED) with acute chest pain; however, many were underpowered. The purpose of this systematic review and meta-analysis is to evaluate the prognostic value and accuracy of a zero (normal) CACS for identifying patients at acceptable low risk for future cardiovascular events who might be safely discharged home from the ED.
We searched multiple databases for longitudinal studies of CACS in symptomatic patients without known coronary artery disease that reported major adverse cardiovascular events (MACEs), including death and myocardial infarction. Pooled risk ratios, sensitivity, specificity, and likelihood ratios were analyzed.
Eight studies evaluated 3,556 patients, with a median follow-up of 10.5 months. Pooled prevalence of zero CACS was 60%. Patients with CACS=0 had a significantly lower risk of cardiovascular events compared with those with CACS greater than 0 (MACEs: relative risk 0.06, 95% confidence interval 0.04 to 0.11, I=0%; death/myocardial infarction: relative risk 0.19; 95% confidence interval 0.08 to 0.47, I=0%). The pooled event rates for CACS=0 (MACEs 0.8%/year; death/myocardial infarction 0.5%/year) were significantly lower than for CACS greater than 0 (MACEs 14.6%/year; death/myocardial infarction 3.5%/year). Analysis of summary testing parameters showed a sensitivity of 96%, specificity of 60%, positive likelihood ratio of 2.36, and negative likelihood ratio of 0.07.
Acute chest pain patients without history of coronary artery disease, ischemic ECG changes, or increased cardiac enzyme levels commonly have a CACS of zero, with a very low subsequent risk of MACEs or death or myocardial infarction. This meta-analysis proffers the potential role of initial CACS testing for avoiding unnecessary hospitalization and further cardiac testing in acute chest pain patients with a CACS of zero.
冠状动脉钙化积分（CACS）是一种成熟的用于对无症状患者进行风险分层的检查。近期研究还表明，CACS可能准确地对因急性胸痛就诊于急诊科（ED）的稳定患者进行风险分层；然而，许多研究的样本量不足。本系统评价和荟萃分析的目的是评估零（正常）CACS对于识别未来心血管事件风险可接受且较低、可能从急诊科安全出院回家的患者的预后价值和准确性。
我们在多个数据库中检索了关于有症状但无已知冠状动脉疾病的患者的CACS纵向研究，这些研究报告了主要不良心血管事件（MACE），包括死亡和心肌梗死。分析了合并风险比、敏感性、特异性和似然比。
八项研究评估了3556例患者，中位随访时间为10.5个月。CACS为零的合并患病率为60%。与CACS大于0的患者相比，CACS = 0的患者发生心血管事件的风险显著更低（MACE：相对风险0.06，95%置信区间0.04至0.11，I² = 0%；死亡/心肌梗死：相对风险0.19；95%置信区间0.08至0.47，I² = 0%）。CACS = 0的合并事件发生率（MACE每年0.8%；死亡/心肌梗死每年0.5%）显著低于CACS大于0的情况（MACE每年14.6%；死亡/心肌梗死每年3.5%）。汇总检验参数分析显示敏感性为96%，特异性为60%，阳性似然比为2.36，阴性似然比为0.07。
无冠状动脉疾病病史、缺血性心电图改变或心肌酶水平升高的急性胸痛患者通常CACS为零，随后发生MACE、死亡或心肌梗死的风险非常低。这项荟萃分析揭示了初始CACS检测在避免CACS为零的急性胸痛患者不必要住院和进一步心脏检查方面的潜在作用。
