Department of Cardiology, Royal Prince Alfred Hospital, University of Sydney, Sydney, Australia.
Circ Cardiovasc Interv. 2012 Aug 1;5(4):515-22. doi: 10.1161/CIRCINTERVENTIONS.112.969048. Epub 2012 Aug 8.
Periprocedural myocardial infarction (MI) occurs in a significant proportion of patients undergoing percutaneous coronary intervention (PCI) and portends poor outcomes. Currently, no clinically applicable method predicts periprocedural MI in the cardiac catheterization laboratory before it occurs. We hypothesized that impaired baseline coronary microcirculatory reserve, which reduces the ability to tolerate ischemic insults, is a risk for periprocedural MI and that the index of microcirculatory resistance (IMR) measured during PCI can predict occurrence of periprocedural MI.
Consecutive patients undergoing elective PCI of a single lesion in the left anterior descending coronary artery were recruited. A pressure-temperature sensor wire was used to measure IMR before PCI. Of the 50 patients studied, 10 had periprocedural MI. From binary logistic regression analyses of all clinical, procedural, and physiological parameters, univariable predictors of periprocedural MI were pre-PCI IMR (P=0.003) and the number of stents used (P=0.039). Pre-PCI IMR was the only independent predictor in bivariable regression analyses performed by adjusting for each available covariate one at a time (all P≤0.02). Pre-PCI IMR ≥27 U had 80.0% sensitivity and 85.0% specificity for predicting periprocedural MI (C statistic, 0.80; P=0.003). Pre-PCI IMR ≥27 U was independently associated with a 23-fold risk of developing periprocedural MI (odds ratio, 22.7; 95% CI, 3.8-133.9).
These data suggest that the status of the coronary microcirculation plays a role in determining susceptibility toward periprocedural MI at the time of elective PCI. The IMR can predict subsequent risk of developing myocardial necrosis and may guide adjunctive prevention strategies.
经皮冠状动脉介入治疗（PCI）过程中会发生相当一部分患者发生围手术期心肌梗死（MI），并预示着预后不良。目前，在发生之前，还没有一种临床适用的方法可以预测心导管室中的围手术期 MI。我们假设，基线冠状动脉微循环储备受损会降低耐受缺血性损伤的能力，这是围手术期 MI 的一个风险因素，并且在 PCI 过程中测量的微血管阻力指数（IMR）可以预测围手术期 MI 的发生。
连续招募了接受左前降支单支病变选择性 PCI 的患者。在 PCI 之前，使用压力-温度传感器线测量 IMR。在研究的 50 名患者中，有 10 名发生了围手术期 MI。在对所有临床、程序和生理参数进行二元逻辑回归分析后，围手术期 MI 的单变量预测因子为 PCI 前的 IMR（P=0.003）和使用的支架数量（P=0.039）。在对每次调整一个可用协变量进行的二变量回归分析中，PCI 前的 IMR 是唯一的独立预测因子（所有 P≤0.02）。PCI 前 IMR≥27U 对预测围手术期 MI 的敏感性为 80.0%，特异性为 85.0%（C 统计量为 0.80；P=0.003）。PCI 前 IMR≥27U 与发生围手术期 MI 的风险增加 23 倍独立相关（优势比为 22.7；95%CI，3.8-133.9）。
这些数据表明，冠状动脉微循环的状态在决定选择性 PCI 时发生围手术期 MI 的易感性方面起着作用。IMR 可以预测随后发生心肌坏死的风险，并可能指导辅助预防策略。
