Department of Cardiology, Westmead Hospital, Sydney, NSW, Australia; University of Sydney, Sydney, NSW, Australia.
Department of Cardiology, Westmead Hospital, Sydney, NSW, Australia.
Heart Lung Circ. 2022 Sep;31(9):1219-1227. doi: 10.1016/j.hlc.2022.05.040. Epub 2022 Jun 24.
Troponin positive chest-pain with unobstructed coronary arteries (TPCP-UCA), occurs in 6% of cases of patients presenting with acute coronary syndrome (ACS). Whilst TPCP-UCA patients are known to be younger with less cardiovascular risk factors when compared to obstructive coronary disease (MICAD), no validated methods exist to reliably delineate these two conditions prior to coronary angiography.
We analysed 142 patients with MICAD and 127 patients with TPCP-UCA from 2015 to 2019. Several key predetermined clinical, biochemical and electrocardiograph (ECG) parameters, as well as Global Registry of Acute Coronary Events (GRACE) score, were collected for all patients. All TPCP-UCA patients underwent cardiac magnetic resonance imaging (cMRI).
Patients with TPCP-UCA were younger than MICAD (44 vs 68 yrs, p<0.01), and with less cardiac risk factors of hypertension (31% vs 68%, p<0.01), hypercholesterolaemia (23% vs 56%, p<0.01), diabetes (11% vs 45%, p<0.01), prior ischaemic heart disease (8% vs 42%, p<0.01) and smoking history (29% vs 50%, p<0.01). Peak troponin (MICAD 2,084.5 ng/L vs TPCP-UCA 847.0 ng/L, p=0.02), serial-to-initial troponin ratio (MICAD 13.5 vs TPCP-UCA 5.1, p<0.01), and peak-to-initial troponin ratio (MICAD 69.6 vs TPCP-UCA 14.0, p<0.01) were all higher in the MICAD group. GRACE scores were significantly different across the two cohorts (TPCP UCA 74 vs MICAD 106, p<0.01), with a receiver operator characteristic (ROC) curve statistic of 0.794 (95% CI 0.739-0.850). On ECG analysis, MICAD had greater prevalence and sum of ST depression (40% vs 19% p<0.01; 1.6 mm vs 0.44 mm, p<0.01) and T wave inversion (37% vs 17%, p<0.01), whilst TPCP-UCA had greater presence of PR depression (20% vs 3% p<0.01), and longer repolarisation (T wave peak to end 89 ms vs 83 ms, p=0.04; T wave peak to end/corrected QT 0.208 ms vs 0.193 ms, p=0.03). All TPCP-UCA patients underwent cMRI. Aetiology was found in 82% of cases, with the leading diagnosis being myocarditis (58%), followed by infarction (8%), whilst 18% had a normal cMRI.
TPCP-UCA is an important differential for patients presenting with ACS, and has several key demographic, biochemical and electrocardiographic differences. The present findings are hypothesis generating, thus prospective studies are required to determine and validate potential clinical utility.
在出现急性冠脉综合征（ACS）的患者中，有 6%存在肌钙蛋白阳性胸痛且冠脉无阻塞（TPCP-UCA）。与阻塞性冠心病（MICAD）相比，TPCP-UCA 患者的年龄更小，心血管危险因素更少，但在冠状动脉造影前，尚无可靠的方法来区分这两种情况。
我们分析了 2015 年至 2019 年间的 142 例 MICAD 患者和 127 例 TPCP-UCA 患者。对所有患者收集了几个关键的预定临床、生化和心电图（ECG）参数，以及全球急性冠脉事件注册（GRACE）评分。所有 TPCP-UCA 患者均接受了心脏磁共振成像（cMRI）检查。
TPCP-UCA 患者比 MICAD 患者年轻（44 岁 vs 68 岁，p<0.01），且高血压（31% vs 68%，p<0.01）、高胆固醇血症（23% vs 56%，p<0.01）、糖尿病（11% vs 45%，p<0.01）、缺血性心脏病既往史（8% vs 42%，p<0.01）和吸烟史（29% vs 50%，p<0.01）的发生率较低。MICAD 组的肌钙蛋白峰值（MICAD 2084.5ng/L vs TPCP-UCA 847.0ng/L，p=0.02）、连续至初始肌钙蛋白比值（MICAD 13.5 vs TPCP-UCA 5.1，p<0.01）和峰值至初始肌钙蛋白比值（MICAD 69.6 vs TPCP-UCA 14.0，p<0.01）均较高。GRACE 评分在两组间有显著差异（TPCP-UCA 74 分 vs MICAD 106 分，p<0.01），其受试者工作特征（ROC）曲线统计量为 0.794（95%CI 0.739-0.850）。在心电图分析中，MICAD 组的 ST 段压低（40% vs 19%，p<0.01；1.6mm vs 0.44mm，p<0.01）和 T 波倒置（37% vs 17%，p<0.01）的发生率较高，而 TPCP-UCA 组的 PR 段压低（20% vs 3%，p<0.01）和复极时间较长（T 波峰值至终点 89ms vs 83ms，p=0.04；T 波峰值至终点/校正 QT 0.208ms vs 0.193ms，p=0.03）。所有 TPCP-UCA 患者均接受了 cMRI 检查。在这些患者中发现了病因，其中 82%为心肌炎，58%为主要诊断，其次为梗死（8%），而 18%的患者 cMRI 正常。
TPCP-UCA 是 ACS 患者的一个重要鉴别诊断，具有几个关键的人口统计学、生化和心电图差异。本研究结果为假说的产生提供了依据，因此需要开展前瞻性研究以确定和验证其潜在的临床应用价值。
