Nedios Sotirios, Tang Min, Roser Mattias, Solowjowa Natalia, Gerds-Li Jin-Hong, Fleck Eckart, Kriatselis Charalampos
Department of Internal Medicine-Cardiology, Deutsches Herzzentrum Berlin, Berlin, Germany.
J Interv Card Electrophysiol. 2011 Nov;32(2):87-94. doi: 10.1007/s10840-011-9591-z. Epub 2011 Jun 11.
Atrial fibrillation (AF) is associated with electroanatomical remodelling of the left atrium (LA), especially with LA dilatation. However, little is known about the changes of the three-dimensional structure of the LA, regarding the type of atrial fibrillation and their prognostic value after an ablative treatment.
One hundred fifteen patients (72 males, 59 ± 11 years) with an indication for AF ablation were prospectively included. Preoperatively, all patients underwent cardiac computed tomography (CCT). A reconstruction of the LA and the pulmonary veins (PV) was made from CCT data using specialized software (EP PreNavigator, Philips, The Netherlands). Left atrial volume (LAV) after exclusion of the atrial appendage (LAA) and the PV was determined. The LA was then arbitrarily divided by a cutting plane, between the anterior segment of the PV ostia and the atrial appendage and parallel to the posterior wall, to anterior-(LA-Ant.) and posterior-LA (LA-Post.). The ratio LA-Ant./LAV was defined as asymmetry index (ASI). The cardiac CT data, of 25 patients (11 women, 47 ± 11 years) without organic heart disease, were similarly studied for the same parameters, as a control group.
Patients with paroxysmal AF (n = 63) had significantly higher LAV (131 ± 31 vs. 95 ± 18 ml, p < 0.001) and higher ASI (61 ± 6 % vs. 57 ± 4, p = 0.002) than the control group. Patients with persistent AF (n = 34) in comparison with paroxysmal AF showed significantly larger volumes (154 ± 44 vs. 131 ± 31 ml, p = 0.007) but no difference in the ASI (60 ± 8% vs. 61 ± 6%, p = 0.63). Finally, patients with long-term persistent AF (n = 18) showed a bigger asymmetry index than the patients with persistent AF (64 ± 5% vs. 60 ± 8%, p = 0.06) but no significant difference in volumes (161 ± 21 vs. 154 ± 44 ml, p = 0.49). LAA and partial LA volumes had a dilatation pattern similar to LAV. During a follow-up of over 25 ± 7 months, AF recurred in 31 (27%) patients. Multivariate analysis showed that ASI and LAV were the only two significant predictors of AF recurrence after ablative treatment. Independent of LAV, an ASI over 60% predicted AF recurrence with 74% sensitivity and 73% specificity.
Characteristic differences of both left atrial volume and geometry exist between the different forms of atrial fibrillation (paroxysmal, persistent and long-term persistent). The asymmetry index is a simple parameter derived by cardiac CT data that reflects these changes of LA geometry and predicts the outcome after the pulmonary vein isolation.
心房颤动（AF）与左心房（LA）的电解剖重塑有关，尤其是与左心房扩张有关。然而，关于心房颤动类型及其消融治疗后的预后价值，左心房三维结构的变化知之甚少。
前瞻性纳入115例有房颤消融指征的患者（72例男性，年龄59±11岁）。术前，所有患者均接受心脏计算机断层扫描（CCT）。使用专门软件（EP PreNavigator，飞利浦，荷兰）从CCT数据重建左心房和肺静脉（PV）。排除心耳（LAA）和肺静脉后测定左心房容积（LAV）。然后通过一个切割平面将左心房任意分割，该平面位于肺静脉口前节段和心耳之间且平行于后壁，分为前左心房（LA-Ant.）和后左心房（LA-Post.）。LA-Ant./LAV比值定义为不对称指数（ASI）。对25例无器质性心脏病的患者（11例女性，年龄47±11岁）的心脏CT数据进行同样参数的研究，作为对照组。
阵发性房颤患者（n = 63）的LAV显著高于对照组（131±31 vs. 95±18 ml，p < 0.001），ASI也更高（61±6% vs. 57±4，p = 0.002）。持续性房颤患者（n = 34）与阵发性房颤患者相比，LAV显著更大（154±44 vs. 131±31 ml，p = 0.007），但ASI无差异（60±8% vs. 61±6%，p = 0.63）。最后，长期持续性房颤患者（n = 18）的不对称指数高于持续性房颤患者（64±5% vs. 60±8%，p = 0.06），但LAV无显著差异（161±21 vs. 154±44 ml，p = 0.49）。LAA和部分左心房容积的扩张模式与LAV相似。在超过25±7个月的随访中，31例（27%）患者房颤复发。多变量分析显示，ASI和LAV是消融治疗后房颤复发仅有的两个显著预测因素。独立于LAV，ASI超过60%预测房颤复发的敏感性为74%，特异性为73%。
不同形式的心房颤动（阵发性、持续性和长期持续性）之间左心房容积和几何形状存在特征性差异。不对称指数是一个通过心脏CT数据得出的简单参数，它反映了左心房几何形状的这些变化，并预测肺静脉隔离后的结果。
