Non-Invasive Cardiovascular Imaging Program and the Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, 75 Francis St, Boston, MA, 02115, USA.
Radiology and Imaging Sciences, National Institutes of Health, Bethesda, MD, USA.
J Cardiovasc Magn Reson. 2017 Dec 28;19(1):107. doi: 10.1186/s12968-017-0420-0.
Impaired left atrial (LA) function is an early marker of cardiac dysfunction and predictor of adverse cardiac events. Herein, we assess LA structure and function in hypertrophy in hypertrophic cardiomyopathy (HCM) sarcomere mutation carriers with and without left ventricular hypertrophy (LVH).
Seventy-three participants of the HCMNet study who underwent cardiovascular magnetic resonance (CMR) imaging were studied, including mutation carriers with overt HCM (n = 34), preclinical mutation carriers without HCM (n = 24) and healthy, familial controls (n = 15).
LA volumes were similar between preclinical, control and overt HCM cohorts after covariate adjustment. However, there was evidence of impaired LA function with decreased LA total emptying function in both preclinical (64 ± 8%) and overt HCM (59 ± 10%), compared with controls (70 ± 7%; p = 0.002 and p = 0.005, respectively). LA passive emptying function was also decreased in overt HCM (35 ± 11%) compared with controls (47 ± 10%; p = 0.006). Both LAtotal emptying function and LA passive emptying function were inversely correlated with the extent of late gadolinium enhancement (LGE; p = 0.005 and p < 0.05, respectively), LV mass (p = 0.02 and p < 0.001) and interventricular septal thickness (p < 0.001 for both) and serum NT-proBNP levels (p < 0.001 for both).
LA dysfunction is detectable by CMR in preclinical HCM mutation carriers despite non-distinguishable LV wall thickness and LA volume. LA function appears most impaired in subjects with overt HCM and a greater extent of LV fibrosis.
左心房（LA）功能障碍是心脏功能障碍的早期标志物，也是不良心脏事件的预测因子。在此，我们评估了肥厚型心肌病（HCM）肌节突变携带者中肥厚型心肌病和无左心室肥厚（LVH）的 LA 结构和功能。
研究了 HCMNet 研究的 73 名接受心血管磁共振（CMR）成像的参与者，包括明显 HCM 的突变携带者（n=34）、无 HCM 的临床前突变携带者（n=24）和健康的家族性对照者（n=15）。
在调整协变量后，临床前、对照组和明显 HCM 队列之间的 LA 容积相似。然而，在临床前（64±8%）和明显 HCM（59±10%）中均存在 LA 功能障碍的证据，表现为 LA 总排空功能降低，而对照组则为 70±7%（p=0.002 和 p=0.005）。与对照组相比，明显 HCM 患者的 LA 被动排空功能也降低（35±11%比 47±10%，p=0.006）。LA 总排空功能和 LA 被动排空功能均与晚期钆增强（LGE）程度呈负相关（p=0.005 和 p<0.05），与 LV 质量（p=0.02 和 p<0.001）和室间隔厚度（两者均为 p<0.001）以及血清 NT-proBNP 水平（两者均为 p<0.001）呈负相关。
尽管 LV 壁厚度和 LA 容积无差异，但 CMR 可检测到临床前 HCM 突变携带者的 LA 功能障碍。LA 功能在明显 HCM 和更大程度的 LV 纤维化患者中最为受损。
