Department of Cardiology, Copenhagen University Hospital - Herlev and Gentofte, Hellerup, Denmark (F.J.O., P.G.J., A.D., N.E.L., T.B.-S.).
Department of Biomedical Sciences (F.J.O., N.E.L., T.B.-S.), University of Copenhagen, Copenhagen, Denmark.
Circ Cardiovasc Imaging. 2024 Mar;17(3):e016197. doi: 10.1161/CIRCIMAGING.123.016197. Epub 2024 Mar 5.
Left atrial (LA) speckle tracking provides detailed information on atrial function. Its utility for predicting subclinical atrial fibrillation (SCAF) is unclear. Therefore, we sought to investigate whether LA strain measures could predict SCAF detected by long-term continuous rhythm monitoring.
This was an echocardiographic substudy of the LOOP study, where elderly at risk of stroke were randomized to receive a loop recorder (Reveal LINQ) or control. Participants who received a loop recorder were included in this analysis. Echocardiography included LA reservoir, conduit, and contraction strain. Participants were followed with continuous rhythm monitoring for SCAF (≥6 minutes). Cox proportional hazards regression was applied to adjust for atrial fibrillation risk factors.
In total, 956 participants were eligible for analysis. Median continuous rhythm monitoring was 35 months (IQR, 20-40 months), during which 278 (29%) were diagnosed with SCAF. The mean age was 74 years, 56% were male, median CHADS-VASc-score was 4. LA reservoir strain was an independent predictor of SCAF after multivariable adjustments (HR, 1.04 [1.02-1.05], per 1% decrease) and so was contraction strain. The findings were unchanged in competing risk analyses and in participants with normal LA size and diastolic function. Participants with low reservoir strain (<33%) had a significantly higher risk of SCAF compared with those with high reservoir strain (incidence rate, 14.5 [12.4-16.9] versus 9.8 [8.2-11.8] events/100 person-years). The same was noted for low versus high contraction strain.
LA reservoir and contraction strain are independent predictors of SCAF in elderly at risk of stroke. This also applies to individuals with normal LA size and diastolic function.
URL: https://www.clinicaltrials.gov; Unique identifier: NCT02036450.
左心房（LA）斑点追踪提供了关于心房功能的详细信息。其预测亚临床心房颤动（SCAF）的效用尚不清楚。因此，我们试图研究 LA 应变测量是否可以预测通过长期连续节律监测检测到的 SCAF。
这是 LOOP 研究的超声心动图子研究，其中患有中风风险的老年人被随机分配接受环记录仪（Reveal LINQ）或对照组。在此分析中包括接受环记录仪的参与者。超声心动图包括 LA 储备、输送和收缩应变。参与者接受连续节律监测以检测 SCAF（≥6 分钟）。Cox 比例风险回归用于调整心房颤动危险因素。
共有 956 名参与者符合分析条件。中位数连续节律监测为 35 个月（IQR，20-40 个月），在此期间，278 名（29%）被诊断为 SCAF。平均年龄为 74 岁，56%为男性，中位数 CHADS-VASc 评分为 4。LA 储备应变是多变量调整后 SCAF 的独立预测因子（HR，1.04 [1.02-1.05]，每降低 1%），收缩应变也是如此。在竞争风险分析和 LA 大小和舒张功能正常的参与者中，结果保持不变。储备应变较低（<33%）的参与者发生 SCAF 的风险明显高于储备应变较高的参与者（发生率，14.5 [12.4-16.9]与 9.8 [8.2-11.8]事件/100 人年）。低收缩应变与高收缩应变相比也是如此。
LA 储备和收缩应变是中风风险老年人 SCAF 的独立预测因子。这也适用于 LA 大小和舒张功能正常的个体。
