Zemrak Filip, Ambale-Venkatesh Bharath, Captur Gabriella, Chrispin Jonathan, Chamera Ela, Habibi Mohammadali, Nazarian Saman, Mohiddin Saidi A, Moon James C, Petersen Steffen E, Lima João A C, Bluemke David A
From the Centre for Advanced Cardiovascular Imaging, Queen Mary University of London, Barts Heart Centre, United Kingdom (F.Z., S.A.M., S.E.P.); Cardiology Division, Department of Medicine, Johns Hopkins Hospital, Baltimore, MD (B.A.-V., J.C., E.C., M.H., S.N., J.A.C.L.); Institute of Cardiovascular Science, University College London, United Kingdom (G.C., J.C.M.); and Department of Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD (D.A.B.).
Circ Cardiovasc Imaging. 2017 Feb;10(2). doi: 10.1161/CIRCIMAGING.116.005379.
Left atrial (LA) size is a marker of diastolic function and is associated with atrial fibrillation and cardiovascular outcomes. However, there are no large population studies measuring LA structure. The relationship of demographics and cardiovascular risk factors to LA size is largely unknown. This study aimed to determine associations of LA size with demographic factors, cardiac structure and function, and cardiovascular risk factors.
LA volume indexed to body surface area was measured by cardiovascular magnetic resonance steady-state free precession and fast gradient echo cine long- and short-axis images in 2576 asymptomatic participants of MESA ([Multi-Ethnic Study of Atherosclerosis] 68.7 years, 53.0% women, white 42.2%, Chinese American 12.0%, black 24.5%, and Hispanic 21.2%) using biplane and short-axis images. The mean LA volume index was 36.5±11.4 mL/m in the entire cohort and 35.5±10.1 mL/m in subjects free of cardiovascular risk factors (n=283). Multivariable analysis included adjustment for demographics, ethnicity, cardiovascular risk factors, serological studies, socioeconomic status, left ventricular structure, and medications. In the adjusted analysis, age (β=0.2 mL/m per year, <0.0001), male sex (β=-4.2 mL/m, <0.0001), obesity (β=1.3 mL/m, <0.01), end-diastolic volume index (β=0.4 mL/m, <0.0001), Chinese American (β=-2.6 mL/m, <0.0001), and Hispanic (β=1.1 mL/m, <0.05) ethnicities were associated with LA volume index. Diabetes mellitus and smoking were not associated with LA volume index. LA volumes measured by steady-state free precession were 3% larger than by fast gradient echo cine cardiovascular magnetic resonance (<0.001).
Age, sex, ethnicity and left ventricular structural parameters were associated with LA size. Importantly, the study provides reference values of normal LA volume index.
左心房（LA）大小是舒张功能的一个指标，与心房颤动和心血管结局相关。然而，尚无大规模人群研究测量LA结构。人口统计学和心血管危险因素与LA大小之间的关系很大程度上未知。本研究旨在确定LA大小与人口统计学因素、心脏结构和功能以及心血管危险因素之间的关联。
在多民族动脉粥样硬化研究（MESA）的2576名无症状参与者（年龄68.7岁，女性占53.0%，白人占42.2%，华裔美国人占12.0%，黑人占24.5%，西班牙裔占21.2%）中，使用双平面和短轴图像，通过心血管磁共振稳态自由进动和快速梯度回波电影长轴和短轴图像测量体表面积指数化的LA容积。整个队列的平均LA容积指数为36.5±11.4 mL/m²，无心血管危险因素的受试者（n = 283）为35.5±10.1 mL/m²。多变量分析包括对人口统计学、种族、心血管危险因素、血清学研究、社会经济地位、左心室结构和药物进行调整。在调整分析中，年龄（β = 0.2 mL/m²每年，P < 0.0001）、男性（β = -4.2 mL/m²，P < 0.0001）、肥胖（β = 1.3 mL/m²，P < 0.01）、舒张末期容积指数（β = 0.4 mL/m²，P < 0.0001）、华裔美国人（β = -2.6 mL/m²，P < 0.0001）和西班牙裔（β = 1.1 mL/m²，P < 0.05）种族与LA容积指数相关。糖尿病和吸烟与LA容积指数无关。通过稳态自由进动测量的LA容积比通过快速梯度回波电影心血管磁共振测量的大3%（P < 0.001）。
年龄、性别、种族和左心室结构参数与LA大小相关。重要的是，该研究提供了正常LA容积指数的参考值。
