Data_Sheet_1_Microcirculation function assessment in acute myocardial infarction: A systematic review of microcirculatory resistance indices.pdf

BackgroundUp to 50% of acute myocardial infarction (MI) patients present with microvascular dysfunction, after a successful percutaneous coronary intervention (PCI), which leads to worse clinical outcomes. The main purpose of this study is to provide a critical appraisal of the emerging role of invasive microvascular resistance indices in the MI setting, using the index of microcirculatory resistance (IMR), hyperemic microvascular resistance (HMR) and zero-flow pressure (Pzf).
MethodsWe systematically explored relevant studies in the context of MI that correlated microcirculation resistance indices with microvascular dysfunction on cardiac magnetic resonance (CMR), microvascular dysfunction occurring in infarct related arteries (IRA) and non-IRA and its relation to clinical outcomes.
ResultsThe microcirculation resistance indices correlated significantly with microvascular obstruction (MVO) and infarct size (IS) on CMR. Although HMR and Pzf seem to have better diagnostic accuracy for MVO and IS, IMR has more validation data. Although, both IMR and HMR were independent predictors of adverse cardiovascular events, HMR has no validated cut-off value and data is limited to small observational studies. The presence of microvascular dysfunction in non-IRA does not impact prognosis.
ConclusionMicrovascular resistance indices are valuable means to evaluate microcirculation function following MI. Microvascular dysfunction relates to the extent of myocardial damage and clinical outcomes after MI.
Systematic review registration[https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021228432], identifier [CRD42021228432].

背景：高达50%的急性心肌梗死（acute myocardial infarction, MI）患者在成功行经皮冠状动脉介入治疗（percutaneous coronary intervention, PCI）后会出现微血管功能障碍，进而导致不良临床结局。本研究的核心目的为：针对急性心肌梗死场景下有创微血管阻力指标的新兴应用价值进行批判性评价，所用指标包括微循环阻力指数（index of microcirculatory resistance, IMR）、充血期微血管阻力（hyperemic microvascular resistance, HMR）以及零流量压力（zero-flow pressure, Pzf）。
方法：本研究系统检索了急性心肌梗死相关研究，这些研究探讨了微循环阻力指标与心脏磁共振成像（cardiac magnetic resonance, CMR）所示微血管功能障碍、梗死相关动脉（infarct related arteries, IRA）与非梗死相关动脉（non-IRA）发生的微血管功能障碍之间的关联，以及上述指标与临床结局的关系。
结果：微循环阻力指标与心脏磁共振成像所示的微血管阻塞（microvascular obstruction, MVO）及梗死面积（infarct size, IS）显著相关。尽管HMR与Pzf对微血管阻塞和梗死面积的诊断准确度似乎更优，但IMR拥有更多的验证数据。虽然IMR与HMR均为心血管不良事件的独立预测因子，但HMR尚无经过验证的截断值，且现有数据仅来自小型观察性研究。非梗死相关动脉的微血管功能障碍并不会对预后产生影响。
结论：微血管阻力指标是评估急性心肌梗死后微血管功能的有效手段。微血管功能障碍与心肌损伤程度及急性心肌梗死后的临床结局密切相关。
系统评价注册信息：[https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021228432]，注册标识符：[CRD42021228432]。