Frankel Cardiovascular Center, University of Michigan, Ann Arbor, Michigan.
Henry Ford Hospital, Detroit, Michigan.
J Card Fail. 2018 Feb;24(2):90-100. doi: 10.1016/j.cardfail.2017.10.010. Epub 2017 Oct 16.
Coronary microvascular dysfunction (MVD) may contribute to the pathogenesis of heart failure with preserved ejection fraction (HFpEF). Using myocardial flow reserve (MFR) measured by positron emission tomography (PET) as an assessment of microvascular function, we hypothesized that abnormal MFR is associated with LV diastolic dysfunction (DD) and reduced LV and LA strain in patients with risk factors for HFpEF and normal epicardial perfusion on cardiac PET.
Retrospective study of patients without heart failure who underwent cardiac rubidium-82 PET and echocardiography. Global MFR was calculated as the ratio of global stress to rest myocardial blood flow. Echocardiographic measures of diastolic function were recorded. Global longitudinal LA and LV strain were measured with a 2-dimensional speckle-tracking technique. Relationships among MFR and echocardiographic measures were assessed with linear regression, analysis of variance, and test for trend. Seventy-three patients (age 64 ± 11 years, 52% male) were identified with no epicardial perfusion defect on cardiac PET and an ejection fraction ≥50%. Decreased MFR was associated with LV DD (P = .02) and increased E/e', an estimation of LV filling pressure (low E/e' [<8] vs. high E/e' [>15], P < .001). MFR was associated with LA strain independent of age, gender, and common comorbidities (adjusted β = 2.6% per unit MFR, P = 0.046); however, MFR was only marginally related to LV strain.
In patients with risk factors for HFpEF, MVD assessed with MFR was associated with DD, increased estimated LV filling pressure, and abnormal LA strain.
冠状动脉微血管功能障碍（MVD）可能导致射血分数保留型心力衰竭（HFpEF）的发病机制。我们假设，使用正电子发射断层扫描（PET）测量的心肌血流储备（MFR）作为微血管功能的评估，异常的 MFR 与 LV 舒张功能障碍（DD）以及 LV 和 LA 应变降低有关，这些患者存在 HFpEF 的危险因素，并且心脏 PET 显示心外膜灌注正常。
对接受放射性铷-82 PET 和超声心动图检查且无心力衰竭的患者进行回顾性研究。将整体 MFR 计算为整体应激与休息心肌血流的比值。记录舒张功能的超声心动图测量值。使用二维斑点追踪技术测量 LA 和 LV 的整体纵向应变。使用线性回归、方差分析和趋势检验评估 MFR 与超声心动图测量值之间的关系。在 73 例患者（年龄 64±11 岁，52%为男性）中，心脏 PET 未见心外膜灌注缺陷，射血分数≥50%。MFR 降低与 LV DD（P=0.02）和 LV 充盈压估计值 E/e'升高（低 E/e' [<8]与高 E/e' [>15]，P<0.001）有关。MFR 与 LA 应变独立于年龄、性别和常见合并症相关（调整后的每单位 MFR 的 β 值为 2.6%，P=0.046）；然而，MFR 与 LV 应变仅有边缘相关性。
在 HFpEF 的危险因素患者中，使用 MFR 评估的 MVD 与 DD、增加的估计 LV 充盈压和异常的 LA 应变有关。
