Division of Cardiovascular Ultrasound, Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota.
Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, Minnesota.
J Am Soc Echocardiogr. 2022 Aug;35(8):818-828.e3. doi: 10.1016/j.echo.2022.03.016. Epub 2022 Mar 26.
The value of left atrial (LA) volume and reservoir function (ResF) after ablation for atrial fibrillation for predicting overall outcomes needs further investigation, particularly in large cohorts. The aim of this study was to test the hypothesis that abnormal LA volume and ResF after ablation are associated with adverse outcomes.
Patients who underwent primary atrial fibrillation ablation between 2007 and 2016 and had available measurements of maximum LA volume index (LAVImax) and minimum LA volume index (LAVImin) and LA ResF (LA emptying fraction and LA expansion index) at 3-month echocardiographic examination after ablation were included in this analysis. The primary endpoint was the composite of cardiac hospitalization for heart failure or acute ischemic events, stroke or transient ischemic attack, and all-cause death; secondary endpoints were cardiac hospitalization and all-cause death.
A total of 792 patients were studied (mean age, 60 ± 10 years). Over a median of 7.5 years (interquartile range, 3.0-9.7 years) of follow-up, 96 patients experienced adverse events. After adjustment for several parameters, including age, comorbidities, and left ventricular structure and function, increased LA volumes and impaired ResF were each independently associated with the primary endpoint (LAVImax > 34 mL/m: adjusted hazard ratio [HR], 2.37 [95% CI, 1.49-3.76; P = .0003]; LAVImin ≥ 20.5 mL/m: adjusted HR, 3.21 [95% CI, 1.97-5.24; P < .0001]; LA emptying fraction < 40%: adjusted HR, 2.00 [95% CI, 1.29-3.10; P = .002]; LA expansion index < 66%: adjusted HR, 1.91 [95% CI, 1.22-2.98; P = .005]) as well as with the secondary endpoints of cardiac hospitalization (P < .05 for adjusted HR for all LA parameters) and all-cause death (P < .05 for adjusted HR for LAVImin, LA emptying fraction and LA expansion index). ResF measures were incremental to LAVImax (P < .05 for all), but not to LAVImin. In patients with normal LA (LAVImax ≤ 34 mL/m; n = 403), those with higher LAVImin (≥17 mL/m) were at 4 times higher risk for primary endpoint events (age-adjusted HR, 4.32; 95% CI, 1.90-9.81; P = .0005). All these findings were independent of atrial tachyarrhythmia recurrence.
Enlarged left atrium and impaired ResF at 3 months after ablation for atrial fibrillation are strongly associated with long-term outcomes, independent of left ventricular function or cardiac rhythm at follow-up. LAVImin showed the strongest associations and even identified a high-risk subgroup among patients with nondilated left atria.
左心房（LA）体积和储备功能（ResF）在房颤消融后的价值，需要进一步研究，以预测整体结果，尤其是在大型队列中。本研究旨在验证消融后 LA 体积和 ResF 异常与不良结局相关的假设。
纳入 2007 年至 2016 年间行首次房颤消融且术后 3 个月行超声心动图检查时 LA 最大容积指数（LAVImax）、LA 最小容积指数（LAVImin）和 LA ResF（LA 排空分数和 LA 扩张指数）有可用测量值的患者。主要终点为心力衰竭或急性缺血事件、卒中和短暂性脑缺血发作、全因死亡的心脏住院复合终点；次要终点为心脏住院和全因死亡。
共纳入 792 例患者（平均年龄 60±10 岁）。中位随访 7.5 年（四分位距 3.0-9.7 年）期间，96 例患者发生不良事件。在校正年龄、合并症、左心室结构和功能等多个参数后，增大的 LA 体积和受损的 ResF 均与主要终点独立相关（LAVImax＞34ml/m：调整后的 HR 为 2.37（95%CI，1.49-3.76；P=0.0003）；LAVImin≥20.5ml/m：调整后的 HR 为 3.21（95%CI，1.97-5.24；P＜0.0001）；LA 排空分数＜40%：调整后的 HR 为 2.00（95%CI，1.29-3.10；P=0.002）；LA 扩张指数＜66%：调整后的 HR 为 1.91（95%CI，1.22-2.98；P=0.005））以及心脏住院（所有 LA 参数调整后的 HR＜0.05）和全因死亡（LAVImin、LA 排空分数和 LA 扩张指数调整后的 HR＜0.05）的次要终点。ResF 指标与 LAVImax 呈增量关系（所有 P＜0.05），但与 LAVImin 无关。在 LA 正常（LAVImax≤34ml/m；n=403）的患者中，LAVImin 较高（≥17ml/m）者发生主要终点事件的风险增加 4 倍（年龄校正的 HR，4.32；95%CI，1.90-9.81；P=0.0005）。所有这些发现均独立于房性快速心律失常的复发。
房颤消融后 3 个月时左心房增大和储备功能受损与长期结局密切相关，独立于左心室功能或随访时的心律。LAVImin 与结局的相关性最强，甚至在左心房不扩张的患者中确定了一个高危亚组。
