ISCHEMIA 试验中的心肌梗死：不同定义对发生率、预后和治疗比较的影响。
Myocardial Infarction in the ISCHEMIA Trial: Impact of Different Definitions on Incidence, Prognosis, and Treatment Comparisons.
机构信息
Saint Louis University School of Medicine, MO (B.R.C.).
Duke Clinical Research Institute, Durham, NC (K.P.A., D.D.C., R.D.L., S.M.O., F.W.R.).
出版信息
Circulation. 2021 Feb 23;143(8):790-804. doi: 10.1161/CIRCULATIONAHA.120.047987. Epub 2020 Dec 3.
BACKGROUND
In the ISCHEMIA trial (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches), an initial invasive strategy did not significantly reduce rates of cardiovascular events or all-cause mortality in comparison with a conservative strategy in patients with stable ischemic heart disease and moderate/severe myocardial ischemia. The most frequent component of composite cardiovascular end points was myocardial infarction (MI).
METHODS
ISCHEMIA prespecified that the primary and major secondary composite end points of the trial be analyzed using 2 MI definitions. For procedural MI, the primary MI definition used creatine kinase-MB as the preferred biomarker, whereas the secondary definition used cardiac troponin. Procedural thresholds were >5 times the upper reference level for percutaneous coronary intervention and >10 times for coronary artery bypass grafting. Procedural MI definitions included (1) a category of elevated biomarker only events with much higher biomarker thresholds, (2) new ST-segment depression of ≥1 mm for the primary and ≥0.5 mm for the secondary definition, and (3) new coronary dissections National Heart, Lung, and Blood Institute grade 3. We compared MI type, frequency, and prognosis by treatment assignment using both MI definitions.
RESULTS
Procedural MIs accounted for 20.1% of all MI events with the primary definition and 40.6% of all MI events with the secondary definition. Four-year MI rates in patients undergoing revascularization were more frequent with the invasive versus conservative strategy using the primary (2.7% versus 1.1%; adjusted hazard ratio [HR], 2.98 [95% CI, 1.87-4.73]) and secondary (8.2% versus 2.0%; adjusted HR, 5.04 [95% CI, 3.64-6.97]) MI definitions. Type 1 MIs were less frequent with the invasive versus conservative strategy using the primary (3.40% versus 6.89%; adjusted HR, 0.53 [95% CI, 0.41-0.69]; <0.0001) and secondary (3.48% versus 6.89%; adjusted HR, 0.53 [95% CI, 0.41-0.69]; <0.0001) definitions. The risk of subsequent cardiovascular death was higher after a type 1 MI than after no MI using the primary (adjusted HR, 3.38 [95% CI, 2.03-5.61]; <0.001) or secondary MI definition (adjusted HR, 3.52 [2.11-5.88]; <0.001).
CONCLUSIONS
In ISCHEMIA, type 1 MI events using the primary and secondary definitions during 5-year follow-up were more frequent with an initial conservative strategy and associated with subsequent cardiovascular death. Procedural MI rates were greater in the invasive strategy and with the use of the secondary MI definition. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01471522.
背景
在 ISCHEMIA 试验（国际比较健康效果研究，比较医学和介入方法）中，与保守策略相比，初始介入策略并未显著降低稳定型缺血性心脏病和中重度心肌缺血患者的心血管事件或全因死亡率。复合心血管终点的最常见组成部分是心肌梗死 (MI)。
方法
ISCHEMIA 预先规定，试验的主要和主要次要复合终点应使用 2 种 MI 定义进行分析。对于程序 MI，首选生物标志物为肌酸激酶同工酶-MB 的主要 MI 定义，而次要定义则使用心肌肌钙蛋白。程序阈值为经皮冠状动脉介入术>5 倍参考上限，冠状动脉旁路移植术>10 倍。程序 MI 定义包括：（1）仅升高生物标志物类别的事件，生物标志物阈值较高；（2）主要和次要定义的新 ST 段压低≥1mm；（3）新的冠状动脉夹层美国国立心肺血液研究所 3 级。我们使用这两种 MI 定义，根据治疗方案比较 MI 类型、频率和预后。
结果
原发性定义的所有 MI 事件中，程序性 MI 占 20.1%，继发性定义的所有 MI 事件中占 40.6%。采用原发性（2.7%对 1.1%；调整后的危险比 [HR]，2.98 [95%CI，1.87-4.73]）和继发性（8.2%对 2.0%；调整后的 HR，5.04 [95%CI，3.64-6.97]）MI 定义，接受血运重建的患者在 4 年时 MI 发生率较高。与保守策略相比，采用原发性（3.40%对 6.89%；调整后的 HR，0.53 [95%CI，0.41-0.69]；<0.0001）和继发性（3.48%对 6.89%；调整后的 HR，0.53 [95%CI，0.41-0.69]；<0.0001）定义，1 型 MI 发生率较低。与无 MI 相比，采用原发性（调整后的 HR，3.38 [95%CI，2.03-5.61]；<0.001）或继发性 MI 定义（调整后的 HR，3.52 [2.11-5.88]；<0.001），1 型 MI 后发生心血管死亡的风险更高。
结论
在 ISCHEMIA 中，在 5 年随访期间使用原发性和继发性定义的 1 型 MI 事件在初始保守策略中更为常见，与随后的心血管死亡有关。侵入性策略和使用继发性 MI 定义会导致更多的程序性 MI 发生。
Zotero 插件