Heart：低危无症状人群动脉粥样硬化并非可忽略不计

　　韩国一项研究表明，在依据指南被分类为低危的无症状人群中，动脉粥样硬化斑块和显著狭窄的发病率并非可忽略不计；但考虑到这些患者的事件发生率较低，因此低危无症状的患者不应行CT血管造影（CCTA）检查。论文于5月30日在线发表于《心脏》（Heart）。

　　此项观察性研究共纳入4339例接受64排CCTA检查的序贯中年无症状受试者，其中2133例（49.2%）为NECP指南分类为低危的受试者。主要转归指标为动脉粥样硬化斑块、显著狭窄的发生率。

　　结果显示，在2133例低危受试者中，11.4%（243例）受试者伴有动脉粥样硬化斑块，1.3%（28例）伴有冠脉显著狭窄，并且有0.8%（18例）伴有由非钙化斑块（NCP）导致的显著狭窄。冠脉显著狭窄受试者和由NCP导致的显著狭窄受试者中分别有75.0%和94.4%为年轻成人。中期随访显示4例受试者出现心脏事件：3例为需住院的不稳定性心绞痛，1例需接受经皮冠脉介入治疗。

The prevalence and characteristics of coronary atherosclerosis in asymptomatic subjects classified as low risk based on traditional risk stratification algorithm: assessment with coronary CT angiography

Objective To evaluate the prevalence and characteristics of coronary atherosclerosis in asymptomatic subjects classified as low risk by National Cholesterol Education Program (NCEP) guideline using coronary CT angiography (CCTA).

Design 

An observational study.

Setting 

A single tertiary referral centre.

Patients 

2133 (49.2%) subjects, who were classified as low risk by the NCEP guideline, of 4339 consecutive middle-aged asymptomatic subjects who underwent CCTA with 64-slice scanners as part of a general health evaluation.

Main outcome measures 

The incidence of atherosclerosis plaques, significant stenosis.

Results 

In the subjects at low risk, 11.4% (243 of 2133) of subjects had atherosclerosis plaques, 1.3% (28 of 2133) of subjects had significant stenosis, and 0.8% (18 of 2133) of subjects had significant stenosis caused by non-calcified plaque (NCP). Especially, 75.0% (21 of 28) of subjects with significant stenosis and 94.4% (17 of 18) of subjects with significant stenosis caused by NCP were young adults. Mid-term follow-up (29.3±14.9 months) revealed four subjects with cardiac events: three subjects with unstable angina requiring hospital stay and one subject with percutaneous coronary intervention.

Conclusions 

Although an asymptomatic population classified as low risk by the NCEP guideline has been regarded as a minimal risk group, the prevalence of atherosclerosis plaques and significant stenosis were not negligible. However, considering very low event rate for those patients, CCTA should not be performed in low-risk asymptomatic subjects, although CCTA might have the potential for identification of high-risk groups in the selected subjects regarded as a minimal-risk group by NCEP guideline.