London School of Hygiene and Tropical Medicine, London, United Kingdom.
The Zena and Michael A. Wiener Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, New York, New York; Clinical Trials Center, Cardiovascular Research Foundation, New York, New York. Electronic address: https://twitter.com/GreggWStone.
J Am Coll Cardiol. 2020 Oct 6;76(14):1609-1621. doi: 10.1016/j.jacc.2020.08.016.
Varying definitions of procedural myocardial infarction (PMI) are in widespread use.
This study sought to determine the rates and clinical relevance of PMI using different definitions in patients with left main coronary artery disease randomized to percutaneous coronary intervention (PCI) versus coronary artery bypass grafting (CABG) surgery in the EXCEL (Evaluation of XIENCE versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization) trial.
The pre-specified protocol definition of PMI (PMI) required a large elevation of creatine kinase-MB (CK-MB), with identical threshold for both procedures. The Third Universal Definition of MI (types 4a and 5) (PMI) required lesser biomarker elevations but with supporting evidence of myocardial ischemia, different after PCI and CABG. For the PMI, troponins were used preferentially (available in 49.5% of patients), CK-MB otherwise. The multivariable relationship between each PMI type and 5-year mortality was determined.
PMI occurred in 34 of 935 (3.6%) patients after PCI and 56 of 923 (6.1%) patients after CABG (difference -2.4%; 95% confidence interval [CI]: -4.4% to -0.5%; p = 0.015). The corresponding rates of PMI were 37 (4.0%) and 20 (2.2%), respectively (difference 1.8%; 95% CI: 0.2% to 3.4%; p = 0.025). Both PMI and PMI were associated with 5-year cardiovascular mortality (adjusted hazard ratio [HR]: 2.18 [95% CI: 1.13 to 4.23] and 2.87 [95% CI: 1.44 to 5.73], respectively). PMI was associated with a consistent hazard of cardiovascular mortality after both PCI and CABG (p = 0.86). Conversely, PMI was strongly associated with cardiovascular mortality after CABG (adjusted HR: 11.94; 95% CI: 4.84 to 29.47) but not after PCI (adjusted HR: 1.14; 95% CI: 0.35 to 3.67) (p = 0.004). Results were similar for all-cause mortality and with varying PMI biomarker definitions. Only large biomarker elevations (CK-MB ≥10× upper reference limit and troponin ≥70× upper reference limit) were associated with mortality.
The rates of PMI after PCI and CABG vary greatly with different definitions. In the EXCEL trial, the pre-specified PMI was associated with similar hazard after PCI and CABG, whereas PMI was strongly associated with mortality after CABG but not after PCI. (EXCEL Clinical Trial [EXCEL]; NCT01205776).
不同的心肌梗死（PMI）定义在广泛应用。
本研究旨在通过不同的定义来确定左主干冠状动脉疾病患者在经皮冠状动脉介入治疗（PCI）与冠状动脉旁路移植术（CABG）治疗中出现 PMI 的发生率和临床相关性。EXCEL 试验（XIENCE 与冠状动脉旁路移植术治疗左主干血运重建效果的评估）将随机分配至 PCI 或 CABG 手术的患者。
PMI 的预设定义（PMI）需要肌酸激酶同工酶-MB（CK-MB）大量升高，两种手术的阈值相同。第三通用心肌梗死定义（类型 4a 和 5）（PMI）需要较少的生物标志物升高，但需要有心肌缺血的支持证据，PCI 和 CABG 后有不同的证据。对于 PMI，首选使用肌钙蛋白（49.5%的患者可获得），否则使用 CK-MB。通过多变量分析确定每种 PMI 类型与 5 年死亡率之间的关系。
PCI 后 935 例患者中有 34 例（3.6%），CABG 后 923 例患者中有 56 例（6.1%）发生 PMI（差异-2.4%；95%置信区间[CI]：-4.4%至-0.5%；p=0.015）。相应的 PMI 发生率分别为 4.0%和 2.2%（差异 1.8%；95%CI：0.2%至 3.4%；p=0.025）。PMI 和 PMI 均与 5 年心血管死亡率相关（校正后的危险比[HR]：2.18 [95%CI：1.13 至 4.23]和 2.87 [95%CI：1.44 至 5.73]）。PMI 在 PCI 和 CABG 后均与心血管死亡率的一致危险相关（p=0.86）。相反，PMI 与 CABG 后心血管死亡率强烈相关（校正 HR：11.94；95%CI：4.84 至 29.47），但与 PCI 后无相关性（校正 HR：1.14；95%CI：0.35 至 3.67）（p=0.004）。所有原因死亡率和不同的 PMI 生物标志物定义结果相似。只有较大的生物标志物升高（CK-MB≥10×参考上限和肌钙蛋白≥70×参考上限）与死亡率相关。
PCI 和 CABG 后 PMI 的发生率差异很大，不同的定义。在 EXCEL 试验中，预设定义的 PMI 在 PCI 和 CABG 后与危险度相似，而 PMI 与 CABG 后死亡率强烈相关，但与 PCI 后无关。（EXCEL 临床试验；NCT01205776）。
