Division of Cardiovascular Medicine, Department of Internal Medicine, Keck School of Medicine of University of Southern California, Los Angeles, California.
Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut.
Am J Physiol Heart Circ Physiol. 2022 Sep 1;323(3):H559-H568. doi: 10.1152/ajpheart.00083.2022. Epub 2022 Aug 12.
Atrial cardiomyopathy has been recognized as having important consequences for cardiac performance and clinical outcomes. The pathophysiological role of the left atrial (LA) appendage and the effect of percutaneous left atrial appendage occlusion (LAAO) upon LA mechanics is incompletely understood. We evaluated if changes in LA stiffness due to endocardial LAAO can be detected by LA pressure-volume (PV) analysis and whether stiffness parameters are associated with baseline characteristics. Patients undergoing percutaneous endocardial LAAO ( = 25) were studied using a novel PV analysis using near-simultaneous three-dimensional LA volume measurements by transesophageal echocardiography (TEE) and direct invasive LA pressure measurements. LA stiffness (dP/dV, change in pressure with change in volume) was calculated before and after LAAO. Overall LA stiffness significantly increased after LAAO compared with baseline (median, 0.41-0.64 mmHg/mL; ≪ 0.001). LA body stiffness after LAAO correlated with baseline LA appendage size by indexed maximum depth (Spearman's rank correlation coefficient = 0.61; < 0.01). LA stiffness change showed an even stronger correlation with baseline LA appendage size by indexed maximum depth ( = 0.70; < 0.001). We found that overall LA stiffness increases after endocardial LAAO. Baseline LA appendage size correlates with the magnitude of increase and LA body stiffness. These findings document alteration of LA mechanics after endocardial LAAO and suggest that the LA appendage modulates overall LA compliance. Our study documents a correlation of LA appendage remodeling with the degree of chronically abnormal LA body stiffness. In addition, we found that LA appendage size was the baseline parameter that best correlated with the magnitude of a further increase in overall LA stiffness after appendage occlusion. These findings offer insights about the LA appendage and LA mechanics that are relevant to patients at risk for adverse atrial remodeling, especially candidates for LA appendage occlusion.
心房心肌病已被认为对心脏功能和临床结局有重要影响。左心房（LA）附属物的病理生理作用以及经皮左心房附属物闭塞（LAAO）对 LA 力学的影响尚不完全清楚。我们评估了由于心内膜 LAAO 导致的 LA 僵硬度变化是否可以通过 LA 压力-容积（PV）分析检测到，以及僵硬度参数是否与基线特征相关。使用经食管超声心动图（TEE）和直接心内 LA 压力测量的近同步三维 LA 容积测量，对接受经皮心内膜 LAAO 的患者（ = 25）进行了一项新的 PV 分析研究。在 LAAO 前后计算 LA 僵硬度（dP/dV，压力随容积变化的变化）。与基线相比，LAAO 后整体 LA 僵硬度显著增加（中位数，0.41-0.64 mmHg/mL； ≪ 0.001）。LAAO 后 LA 体僵硬度与基线 LA 附属物大小（通过索引最大深度）呈正相关（Spearman 秩相关系数 = 0.61； < 0.01）。LA 僵硬度变化与基线 LA 附属物大小（通过索引最大深度）的相关性甚至更强（ = 0.70； < 0.001）。我们发现心内膜 LAAO 后整体 LA 僵硬度增加。基线 LA 附属物大小与增加幅度相关，LA 体僵硬度也与增加幅度相关。这些发现记录了心内膜 LAAO 后 LA 力学的改变，并表明 LA 附属物调节整体 LA 顺应性。我们的研究记录了 LA 附属物重塑与慢性异常 LA 体僵硬度程度的相关性。此外，我们发现 LA 附属物大小是与 LAAO 后整体 LA 僵硬度进一步增加幅度相关性最好的基线参数。这些发现为 LA 附属物和 LA 力学提供了一些见解，这些见解与有发生不良心房重构风险的患者相关，特别是 LA 附属物闭塞的候选者。
