Department of Acute and Tertiary Care Nursing, University of Pittsburgh, Pittsburgh, PA, United States.
University of Pittsburgh Medical Center (UPMC), Pittsburgh, PA, United States.
Emerg Med J. 2019 Oct;36(10):601-607. doi: 10.1136/emermed-2019-208529. Epub 2019 Jul 31.
Chest pain is among the leading causes for emergency medical services (EMS) activation. Acute myocardial infarction (MI) is not only one of the most critical aetiologies of chest pain, but also one of few conditions encountered by EMS that has been shown to follow a circadian pattern. Understanding the diurnal relationship between the inflow of chest pain patients and the likelihood of acute MI may inform prehospital and emergency department (ED) healthcare providers regarding the prediction, and hence prevention, of dire outcomes.
This was a secondary analysis of previously collected data from an observational prospective study that enrolled consecutive chest pain patients transported by a large metropolitan EMS system in the USA. We used the time of EMS call to determine the time-of-day of the indexed encounter. Two independent reviewers examined available medical data to determine our primary outcome, the presence of MI, and our secondary outcomes, infarct size and 30-day major adverse cardiac events (MACE). We estimated infarct size using peak troponin level.
We enrolled 2065 patients (age 56±17, 53% males, 7.5% with MI). Chest pain encounters increased from 9:00 AM to 2:00 PM, with a peak at 1:00 PM and a nadir at 6:00 AM. Acute MI had a bimodal distribution with two peaks: 10 AM in ST-elevation MI, and 10 PM in non-ST-elevation MI. ST-elevation MI with afternoon onset was an independent predictor of infarct size. Acute MI with winter and early spring presentation was an independent predictor of 30-day MACE.
EMS-attended chest pain calls follow a diurnal pattern, with the most vulnerable patients encountered during afternoons and winter/spring seasons. These data can inform prehospital and ED healthcare providers regarding the time of presentation where patients are more likely to have an underlying MI and subsequently worse outcomes.
胸痛是导致紧急医疗服务（EMS）启动的主要原因之一。急性心肌梗死（MI）不仅是胸痛的最关键病因之一，也是 EMS 遇到的为数不多的具有昼夜节律模式的病症之一。了解胸痛患者就诊的昼夜关系以及急性 MI 的可能性，可能为院前和急诊科（ED）医护人员提供有关预测和预防严重后果的信息。
这是对先前在美国一家大型大都市 EMS 系统连续转运的胸痛患者进行的观察性前瞻性研究中收集的数据的二次分析。我们使用 EMS 呼叫时间来确定索引就诊的时间。两名独立的审查员检查了可用的医疗数据，以确定我们的主要结局，即 MI 的存在，以及我们的次要结局，即梗死面积和 30 天主要不良心脏事件（MACE）。我们使用峰值肌钙蛋白水平来估计梗死面积。
我们共纳入 2065 名患者（年龄 56±17 岁，53%为男性，7.5%患有 MI）。胸痛就诊次数从上午 9:00 增加到下午 2:00，1:00 达到峰值，6:00 达到低谷。急性 MI 呈双峰分布，有两个高峰：ST 段抬高型 MI 为上午 10:00，非 ST 段抬高型 MI 为晚上 10:00。下午发病的 ST 段抬高型 MI 是梗死面积的独立预测因素。冬季和早春发病的急性 MI 是 30 天 MACE 的独立预测因素。
EMS 处理的胸痛就诊次数呈昼夜模式，下午和冬春季节就诊的患者病情最为严重。这些数据可以为院前和 ED 医护人员提供有关患者更有可能患有潜在 MI 并随后出现更差结局的就诊时间的信息。
