BackgroundLeft atrial (LA) myopathy is thought to be associated with silent brain infarctions (SBI) through changes in blood flow hemodynamics leading to thrombogenesis. 4D‐flow MRI enables in‐vivo hemodynamic quantification in the left atrium (LA) and LA appendage (LAA).PurposeTo determine whether LA and LAA hemodynamic and volumetric parameters are associated with SBI.Study TypeProspective observational study.PopulationA single‐site cohort of 125 Participants of the multiethnic study of atherosclerosis (MESA), mean age: 72.3 ± 7.2 years, 56 men.Field Strength/Sequence1.5T. Cardiac MRI: Cine balanced steady state free precession (bSSFP) and 4D‐flow sequences. Brain MRI: T1‐ and T2‐weighted SE and FLAIR.AssessmentPresence of SBI was determined from brain MRI by neuroradiologists according to routine diagnostic criteria in all participants without a history of stroke based on the MESA database. Minimum and maximum LA volumes and ejection fraction were calculated from bSSFP data. Blood stasis (% of voxels <10 cm/sec) and peak velocity (cm/sec) in the LA and LAA were assessed by a radiologist using an established 4D‐flow workflow.Statistical TestsStudent's t test, Mann–Whitney U test, one‐way ANOVA, chi‐square test. Multivariable stepwise logistic regression with automatic forward and backward selection. Significance level P < 0.05.Results26 (20.8%) had at least one SBI. After Bonferroni correction, participants with SBI were significantly older and had significantly lower peak velocities in the LAA. In multivariable analyses, age (per 10‐years) (odds ratio (OR) = 1.99 (95% confidence interval (CI): 1.30–3.04)) and LAA peak velocity (per cm/sec) (OR = 0.87 (95% CI: 0.81–0.93)) were significantly associated with SBI.ConclusionOlder age and lower LAA peak velocity were associated with SBI in multivariable analyses whereas volumetric‐based measures from cardiac MRI or cardiovascular risk factors were not. Cardiac 4D‐flow MRI showed potential to serve as a novel imaging marker for SBI.Level of Evidence3Technical EfficacyStage 2

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左心房及左心耳血流动力学与无症状性脑梗死相关性的 MRI 研究

背景左心房（LA）肌病被认为与无症状脑梗塞（SBI）有关，通过血流动力学的变化导致血栓形成。 4D 流 MRI 能够对左心房 (LA) 和 LA 心耳 (LAA) 进行体内血流动力学定量。目的确定 LA 和 LAA 血流动力学和体积参数是否与 SBI 相关。研究类型前瞻性观察研究。人群单中心队列动脉粥样硬化多种族研究 (MESA) 的 125 名参与者，平均年龄：72.3 ± 7.2 岁，56 名男性。场强/序列1.5T。心脏 MRI：电影平衡稳态自由进动 (bSSFP) 和 4D 流序列。脑 MRI：T1 和 T2 加权 SE 和 FLAIR。评估 SBI 的存在是由神经放射科医生根据 MESA 数据库的所有无中风病史的参与者的常规诊断标准，通过脑 MRI 确定的。最小和最大 LA 体积以及射血分数根据 bSSFP 数据计算。放射科医生使用已建立的 4D 流工作流程评估 LA 和 LAA 中的血瘀（<10 厘米/秒的体素百分比）和峰值速度（厘米/秒）。 统计测试学生的t检验、曼-惠特尼 U 检验、单向方差分析、卡方检验。具有自动向前和向后选择的多变量逐步逻辑回归。显着性水平磷< 0.05。结果26 (20.8%) 至少有一个 SBI。经过 Bonferroni 校正后，患有 SBI 的参与者年龄明显变大，左心耳峰值速度也显着降低。在多变量分析中，年龄（每 10 年）（比值比 (OR) = 1.99（95% 置信区间 (CI)：1.30–3.04））和 LAA 峰值速度（每厘米/秒）（OR = 0.87（95% CI: 0.81–0.93)) 与 SBI 显着相关。结论 在多变量分析中，年龄较大和较低的 LAA 峰值速度与 SBI 相关，而心脏 MRI 或心血管危险因素的基于体积的测量则不然。心脏 4D 流 MRI 显示出作为 SBI 的新型成像标记物的潜力。证据级别 3 技术功效阶段 2