Department of Radiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA.
Department of Radiology, Stanford University, Stanford, California, USA.
J Magn Reson Imaging. 2024 Sep;60(3):988-998. doi: 10.1002/jmri.29137. Epub 2023 Nov 21.
MRI-derived left atrial (LA) longitudinal strain has been shown to be a marker for mitral regurgitation, but the utility of LA circumferential strain remains unclear.
To assess feasibility and reproducibility of LA circumferential strain, identify changes in mitral regurgitation patients compared to healthy volunteers, and determine strain's association with mitral regurgitation severity and cardiac function.
Retrospective.
52 mitral regurgitation patients, 12 healthy volunteers.
FIELD STRENGTH/SEQUENCE: Steady-state free precession cine and 2D phase contrast sequences at 1.5T.
Peak LA circumferential strain was computed in each of three short-axis slices (superior, mid, and inferior) and longitudinal strain computed from long-axis slices using MRI feature-tracking software. Strain test-retest reproducibility was determined from two repeat studies in healthy volunteers.
LA circumferential strain test-retest reproducibility was assessed by intra-class correlation coefficient (ICC). Strain was compared between cohorts using Student's t-test or Mann-Whitney U. Mitral regurgitation severity association with strain and LV function was assessed using Spearman correlation and multivariable regression. Significance was defined as P < 0.05.
LA circumferential strain assessment was feasible in all subjects with moderate reproducibility in the superior (ICC = 0.74), mid LA (ICC = 0.71), and inferior LA (ICC = 0.63). In mitral regurgitation patients, LA circumferential strain was significantly lower in the superior (11.86% [6.5%,19.2%] vs. 18.73% ± 6.7%) and mid LA slices (18.41% ± 9.5% vs. 28.7% ± 10.4%) compared to healthy volunteers. Mitral regurgitation severity significantly associated with mid LA circumferential strain (β = -0.03) and LAV significantly associated with superior LA circumferential strain (β = -2.09), both independent of LA longitudinal strain and CO.
LA circumferential strain assessment is feasible with moderate reproducibility. Compared to healthy volunteers, patients had significantly lower LA circumferential strain. Mitral regurgitation severity and LAV were significantly associated with LA circumferential strain independent of LA longitudinal strain.
3 TECHNICAL EFFICACY: Stage 2.
MRI 衍生的左心房（LA）纵向应变已被证明是二尖瓣反流的标志物，但 LA 周向应变的实用性仍不清楚。
评估 LA 周向应变的可行性和可重复性，确定与健康志愿者相比，二尖瓣反流患者的变化，并确定应变与二尖瓣反流严重程度和心功能的关系。
回顾性。
52 例二尖瓣反流患者，12 例健康志愿者。
磁场强度/序列：1.5T 稳态自由进动电影和 2D 相位对比序列。
使用 MRI 特征跟踪软件在三个短轴切片（上、中、下）中计算 LA 周向应变峰值，在长轴切片中计算 LA 纵向应变。在健康志愿者的两项重复研究中确定应变测试-再测试的可重复性。
使用组内相关系数（ICC）评估 LA 周向应变测试-再测试的可重复性。使用 Student t 检验或 Mann-Whitney U 检验比较两组间的应变。使用 Spearman 相关和多变量回归评估二尖瓣反流严重程度与应变和 LV 功能的关系。定义显著性为 P < 0.05。
所有受试者的 LA 周向应变评估均可行，上 LA（ICC=0.74）、中 LA（ICC=0.71）和下 LA（ICC=0.63）的可重复性中等。在二尖瓣反流患者中，上 LA （11.86%[6.5%，19.2%] vs. 18.73%±6.7%）和中 LA 切片（18.41%±9.5% vs. 28.7%±10.4%）的周向应变明显低于健康志愿者。二尖瓣反流严重程度与中 LA 周向应变显著相关（β=-0.03），LAV 与上 LA 周向应变显著相关（β=-2.09），两者均独立于 LA 纵向应变和 CO。
LA 周向应变评估具有中等可重复性，是可行的。与健康志愿者相比，患者的 LA 周向应变明显较低。二尖瓣反流严重程度和 LAV 与 LA 周向应变显著相关，与 LA 纵向应变无关。
3 级技术功效：2 级。
