Catharina Hospital, Eindhoven, the Netherlands.
Catharina Hospital, Eindhoven, the Netherlands.
Int J Cardiol. 2021 Jun 15;333:21-28. doi: 10.1016/j.ijcard.2021.02.055. Epub 2021 Mar 3.
It is already known that high coronary microvascular resistance (Rμ) is linked to altered left ventricular stiffness and might be an early indicator of heart failure with preserved ejection fraction (HFpEF). Left atrial dysfunction, on the other hand, varies according to the grade of left ventricular diastolic dysfunction. This is the first study to use the latest development for invasive assessment of Rμ and to combine it with echocardiographic assessment of left atrial strain during reservoir phase (LAS) by speckle tracking in relation to left ventricular (LV) diastolic function.
An invasive angiogram was performed in 97 patients because of suspected ANOCA. All patients underwent comprehensive echocardiography, yet image quality was poor in 15 patients leaving 82 patients to include in the final analysis. In order to compare Rμ with LAS values, patients were divided into 4 groups based upon normal values of Rμ as defined by Fournier et al. The mean LAS was plotted against the four resistance groups. The LAS was 48.6% in the lowest resistance group, and 40.1%, 36.3% and 30.1% in the low intermediate, high intermediate and high resistance group respectively. These differences were significant compared to the lowest resistance group (p < 0.05). Although higher Rμ groups showed more diastolic dysfunction, LAS was already decreased irrespective of the severity of diastolic dysfunction.
This study shows a relationship between increased Rμ and reduced LAS, that seems to precede conventional measures of left ventricular diastolic dysfunction. This suggests that microvascular dysfunction might be an early indicator for the development of impaired LA function.
已知冠状动脉微血管阻力（Rμ）升高与左心室僵硬度改变有关，并且可能是射血分数保留的心力衰竭（HFpEF）的早期指标。另一方面，左心房功能障碍随左心室舒张功能障碍的严重程度而变化。这是第一项使用最新的侵入性评估 Rμ 的研究，并将其与斑点追踪法评估储存期左心房应变（LAS）与左心室（LV）舒张功能相结合。
由于疑似 ANOCA，对 97 例患者进行了侵入性血管造影。所有患者均接受了全面的超声心动图检查，但 15 例患者的图像质量较差，最终有 82 例患者纳入最终分析。为了比较 Rμ 与 LAS 值，根据 Fournier 等人定义的 Rμ 的正常值将患者分为 4 组。绘制平均 LAS 与四个阻力组的关系。最低阻力组的 LAS 为 48.6%，低中阻力组、高中阻力组、高阻力组的 LAS 分别为 40.1%、36.3%和 30.1%。与最低阻力组相比，这些差异具有统计学意义（p<0.05）。尽管较高的 Rμ 组显示出更多的舒张功能障碍，但无论舒张功能障碍的严重程度如何，LAS 已经降低。
本研究显示 Rμ 增加与 LAS 降低之间存在关系，这似乎先于传统的左心室舒张功能障碍测量。这表明微血管功能障碍可能是左心房功能障碍发展的早期指标。
