Department of Magnetic Resonance Imaging, Fuwai Hospital and National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 167 Beilishi Road, Beijing, 100037, China.
Department of Radiology, The People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, China.
BMC Cardiovasc Disord. 2022 Mar 13;22(1):99. doi: 10.1186/s12872-022-02532-w.
The role of the dysfunction of left atrium in the occurrence and development of cardiovascular disease has been gradually recognized. We aim to compare the impact on left atrial (LA) function between patients with hypertrophic cardiomyopathy (HCM) and hypertension (HTN) without LA enlargement using cardiovascular magnetic resonance feature tracking (CMR-FT), and if possible, explore the capability of LA function for providing clinical implication and predicting clinical adverse events in the early stage of cardiovascular disease.
Consecutive 60 HCM patients and 60 HTN patients with normal LA size among 1413 patients who underwent CMR were retrospectively analyzed as well as 60 controls. Left atrial and ventricular functions were quantified by volumetric and CMR-FT derived strain analysis from long and short left ventricular view cines. The primary endpoint was a composite of all-cause death, stroke, new-onset or worsening heart failure to hospitalization, and paroxysmal or persistent atrial fibrillation.
Compared to the controls, both HTN and HCM participants had impaired LA reservoir function (εs) and conduit function (εe) with the different stage of LA booster pump dysfunction (εa). LA strain was more sensitive than LV longitudinal strain (GLS) for evaluate primary endpoint (εs: 33.9% ± 7.5 vs. 41.2% ± 14.3, p = 0.02; εe: 13.6% ± 6.2 vs. 17.4% ± 10.4, p = 0.03; εa: 20.2% ± 6.0 vs. 23.7% ± 8.8, p = 0.07; GLS: -19.4% ± 6.4 vs. -20.0% ± 6.8, p = 0.70, respectively). After a mean follow-up of 6.8 years, 23 patients reached primary endpoint. Cox regression analyses indicated impaired LA reservoir and booster pump strain were associated with clinical outcomes in patients at the early stage of HTN and HCM (p < 0.05).
CMR-FT-derived strain is a potential and robust tool in demonstrating impaired LA mechanics, quantifying LA dynamics and underlining the impacts on LA-LV coupling in patients with HTN and HCM without LA enlargement. The corresponding LA dysfunction is a promising metric to assess clinical implication and predict prognosis at the early stage, superior to GLS.
左心房功能障碍在心血管疾病的发生和发展中的作用已逐渐被认识。我们旨在使用心血管磁共振特征追踪（CMR-FT）比较肥厚型心肌病（HCM）和高血压（HTN）患者与左心房（LA）不增大患者的左心房（LA）功能的影响，并在可能的情况下，探讨 LA 功能在心血管疾病早期提供临床意义和预测临床不良事件的能力。
回顾性分析了 1413 例接受 CMR 的患者中 60 例 HCM 患者和 60 例 HTN 患者（LA 大小正常），以及 60 例对照者。通过长轴和短轴左心室电影的容积和 CMR-FT 衍生应变分析来量化左心房和左心室功能。主要终点是全因死亡、卒中和新发或恶化的心力衰竭住院、阵发性或持续性心房颤动的综合事件。
与对照组相比，HTN 和 HCM 患者的 LA 储器功能（εs）和输送功能（εe）均受损，LA 辅助泵功能（εa）出现不同阶段的功能障碍。LA 应变比 LV 纵向应变（GLS）更能敏感地评估主要终点（εs：33.9%±7.5%比 41.2%±14.3%，p=0.02；εe：13.6%±6.2%比 17.4%±10.4%，p=0.03；εa：20.2%±6.0%比 23.7%±8.8%，p=0.07；GLS：-19.4%±6.4%比-20.0%±6.8%，p=0.70）。在平均 6.8 年的随访后，23 例患者达到了主要终点。Cox 回归分析表明，在 HTN 和 HCM 早期患者中，LA 储器和辅助泵应变与临床结局相关（p<0.05）。
CMR-FT 衍生应变是一种潜在的、强大的工具，可用于显示 LA 力学受损、量化 LA 动力学，并强调 HTN 和 HCM 患者 LA 不增大时 LA-LV 耦联的影响。相应的 LA 功能障碍是评估临床意义和预测早期预后的有前途的指标，优于 GLS。
