Comprehensive Arrhythmia Research and Management (CARMA) Center, University of Utah, Salt Lake City, Utah, USA.
J Cardiovasc Electrophysiol. 2012 Jan;23(1):44-50. doi: 10.1111/j.1540-8167.2011.02140.x. Epub 2011 Aug 1.
Sinus node dysfunction (SND) commonly manifests with atrial arrhythmias alternating with sinus pauses and sinus bradycardia. The underlying process is thought to be because of atrial fibrosis. We assessed the value of atrial fibrosis, quantified using late gadolinium enhanced-MRI (LGE-MRI), in predicting significant SND requiring pacemaker implant.
Three hundred forty-four patients with atrial fibrillation (AF) presenting for catheter ablation underwent LGE-MRI. Left atrial (LA) fibrosis was quantified in all patients and right atrial (RA) fibrosis in 134 patients. All patients underwent catheter ablation with pulmonary vein isolation with posterior wall and septal debulking. Patients were followed prospectively for 329 ± 245 days. Ambulatory monitoring was instituted every 3 months. Symptomatic pauses and bradycardia were treated with pacemaker implantation per published guidelines.
The average patient age was 65 ± 12 years. The average wall fibrosis was 16.7 ± 11.1% in the LA, and 5.3 ± 6.4% in the RA. RA fibrosis was correlated with LA fibrosis (R(2) = 0.26; P < 0.01). Patients were divided into 4 stages of LA fibrosis (Utah I: <5%, Utah II: 5-20%, Utah III: 20-35%, Utah IV: >35%). Twenty-two patients (mean atrial fibrosis, 23.9%) required pacemaker implantation during follow-up. Univariate and multivariate analysis identified LA fibrosis stage (OR, 2.2) as a significant predictor for pacemaker implantation with an area under the curve of 0.704.
In patients with AF presenting for catheter ablation, LGE-MRI quantification of atrial fibrosis demonstrates preferential LA involvement. Significant atrial fibrosis is associated with clinically significant SND requiring pacemaker implantation.
窦房结功能障碍（SND）常表现为房性心律失常与窦性停搏和窦性心动过缓交替。其潜在过程被认为是由于心房纤维化。我们评估了使用钆延迟增强磁共振成像（LGE-MRI）定量测量的心房纤维化在预测需要起搏器植入的显著 SND 中的价值。
344 名因心房颤动（AF）而接受导管消融治疗的患者进行了 LGE-MRI 检查。所有患者均对左心房（LA）纤维化进行了量化，134 名患者对右心房（RA）纤维化进行了量化。所有患者均接受了肺静脉隔离术，同时进行了后墙和间隔去脂术。前瞻性随访患者 329 ± 245 天。每 3 个月进行一次动态监测。根据已发表的指南，对有症状的停搏和心动过缓进行起搏器植入治疗。
患者的平均年龄为 65 ± 12 岁。LA 的平均壁纤维化程度为 16.7 ± 11.1%，RA 的平均壁纤维化程度为 5.3 ± 6.4%。RA 纤维化与 LA 纤维化相关（R2 = 0.26；P < 0.01）。患者被分为 4 个 LA 纤维化阶段（犹他州 I：<5%，犹他州 II：5-20%，犹他州 III：20-35%，犹他州 IV：>35%）。22 例（平均心房纤维化程度为 23.9%）在随访期间需要植入起搏器。单因素和多因素分析均表明，LA 纤维化分期（OR，2.2）是起搏器植入的显著预测因子，曲线下面积为 0.704。
在因导管消融治疗而就诊的 AF 患者中，LGE-MRI 定量心房纤维化显示出左心房的优先受累。明显的心房纤维化与需要起搏器植入的临床显著 SND 相关。
