Yang Chia-Hung, Liu Hao-Tien, Lee Hui-Ling, Lin Fen-Chiung, Chou Chung-Chuan
Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou Branch, Taoyuan.
Department of Internal Medicine, New Taipei Municipal TuCheng Hospital, New Taipei.
Quant Imaging Med Surg. 2022 Apr;12(4):2523-2534. doi: 10.21037/qims-21-954.
Left atrial (LA) dimension ≥50 mm had approximately four times the risk of developing atrial fibrillation (AF). The aim of this study was to investigate whether the application of clinical and echocardiographic parameters could differentiate between the patients having severely dilated left atrium with and without AF.
This retrospective cross-sectional study enrolled consecutive patients with LA dimension ≥50 mm and divided them into three groups: no AF (no-AF), paroxysmal AF (PAF) and non-paroxysmal AF (non-PAF) groups. For PAF and non-PAF groups, all patients underwent radiofrequency ablation, and the echocardiographic parameters were obtained on the next day after ablation.
Our study population comprised 160 patients, including 80, 53, and 27 patients in the non-AF, PAF and non-PAF groups, respectively. The no-AF group had a significantly higher body mass index (kg/m) (29.31±6.27, 27.58±4.12 and 26.57±2.81, P=0.01), and a higher prevalence of diabetes mellitus (DM) [31 (38.80%), 13 (25.00%) and 4 (14.80%), P=0.01] and hypertension [67 (83.80%), 34 (65.40%), and 19 (70.40%), P=0.04], but a lower prevalence of rheumatic heart disease (RHD) [3 (3.80%), 6 (11.50%) and 5 (18.50%), P=0.02] and sick sinus syndrome [0 (0.00%), 6 (11.50%) and 4 (14.80%), P=0.045]. Echocardiographic studies showed that the non-AF group had significantly smaller LA minimal volume index (24.89±9.74, 34.06±19.38 and 42.83±17.44 mL/m, P<0.01), higher LA emptying fraction (51.99%±13.97%, 38.40%±15.96% and 33.89%±10.73%, P<0.01), longitudinal strain (23.87%±7.72%, 17.11%±8.52% and 12.38%±4.28%, P<0.01) and strain rate than the AF groups. The multivariate analysis showed that the late diastolic component of LA strain rate was the only independent factor associated with the presence of AF (odds ratio, 21.69; 95% CI, 9.77-48.13, P<0.01).
LA function plays an important role in the absence of AF in patients with LA dimension ≥50 mm; the late diastolic component of LA strain rate was the only independent variable on multivariate analysis.
左心房（LA）直径≥50mm的患者发生心房颤动（AF）的风险约为四倍。本研究的目的是调查临床和超声心动图参数的应用是否能够区分严重扩张的左心房伴或不伴有AF的患者。
这项回顾性横断面研究纳入了连续的LA直径≥50mm的患者，并将他们分为三组：无AF（无AF组）、阵发性AF（PAF）组和非阵发性AF（非PAF）组。对于PAF组和非PAF组，所有患者均接受了射频消融治疗，并在消融后第二天获取超声心动图参数。
我们的研究人群包括160例患者，其中无AF组、PAF组和非PAF组分别有80例、53例和27例患者。无AF组的体重指数（kg/m）显著更高（分别为29.31±6.27、27.58±4.12和26.57±2.81，P=0.01），糖尿病（DM）患病率更高[分别为31例（38.80%）、13例（25.00%）和4例（14.80%），P=0.01]，高血压患病率也更高[分别为67例（83.80%）、34例（65.40%）和19例（70.40%），P=0.04]，但风湿性心脏病（RHD）患病率更低[分别为3例（3.80%）、6例（11.50%）和5例（18.50%），P=0.02]，病态窦房结综合征患病率也更低[分别为0例（0.00%）、6例（11.50%）和4例（14.80%），P=0.045]。超声心动图研究表明，无AF组的左心房最小容积指数显著更小（分别为24.89±9.74、34.06±19.38和42.83±17.44mL/m，P<0.01），左心房排空分数更高（分别为51.99%±13.97%、38.40%±15.96%和33.89%±10.73%，P<0.01），纵向应变（分别为23.87%±7.72%、17.11%±8.52%和12.38%±4.28%，P<0.01）以及应变率均高于AF组。多变量分析表明，左心房应变率的舒张晚期成分是与AF存在相关的唯一独立因素（比值比，21.69；95%置信区间，9.77 - 48.13，P<0.01）。
左心房功能在LA直径≥50mm的无AF患者中起重要作用；多变量分析中左心房应变率的舒张晚期成分是唯一的独立变量。
