Institute of Cardiology, University of Bologna, Via Massarenti 9, 40138, Bologna, Italy.
Stroke. 2011 Jun;42(6):1768-70. doi: 10.1161/STROKEAHA.110.609297. Epub 2011 Apr 14.
In patients with atrial fibrillation (AF), stroke risk stratification schema do not consider AF parameters. The aim of the study is to assess the impact of combining risk factors with continuous AF burden monitoring.
In this retrospective study 568 patients implanted with a DDDR-P pacemaker (AT-500; Medtronic) and a history of AF were continuously monitored for 1 year.
During follow-up, 14 patients (2.5%) had a thromboembolic event. Patients were divided into 3 groups: AF burden ≤5 minutes per day (AF-free; n=223 [39%]), AF burden >5 minutes but <24 hours per day (AF-5 minutes; n=179 [32%]), and AF burden ≥24 hours (AF-24 hours; n=166 [29%]). Patients were also classified according to CHADS2 and CHA2DS2-VASc risk scores. The discrimination ability of each risk score was evaluated performing a logistic regression analysis and calculating the corresponding C-statistic. The addition of AF burden improved C-statistics: for CHADS2 from 0.653 (P=0.051) to 0.713 (P=0.007); for CHA2DS2-VASc, from 0.898 (P<0.0001) to 0.910 (P<0.0001).
The CHA2DS2-VASc score had a high sensitivity to predict thromboembolism. Implementation of device data on AF presence/duration/burden has the potential to contribute to improved clinical risk stratification and should be tested prospectively.
在心房颤动（AF）患者中，卒中风险分层方案并未考虑 AF 参数。本研究旨在评估将危险因素与连续 AF 负荷监测相结合的影响。
在这项回顾性研究中，对 568 例植入 DDDR-P 起搏器（AT-500；美敦力）且有 AF 病史的患者进行了为期 1 年的连续监测。
在随访期间，14 例患者（2.5%）发生血栓栓塞事件。患者被分为 3 组：AF 负荷≤5 分钟/天（无 AF 组；n=223 [39%]）、AF 负荷>5 分钟但<24 小时/天（AF-5 分钟组；n=179 [32%]）和 AF 负荷≥24 小时（AF-24 小时组；n=166 [29%]）。患者还根据 CHADS2 和 CHA2DS2-VASc 风险评分进行了分类。使用逻辑回归分析评估每个风险评分的判别能力，并计算相应的 C 统计量。AF 负荷的增加改善了 C 统计量：对于 CHADS2，从 0.653（P=0.051）增加到 0.713（P=0.007）；对于 CHA2DS2-VASc，从 0.898（P<0.0001）增加到 0.910（P<0.0001）。
CHA2DS2-VASc 评分对预测血栓栓塞具有较高的敏感性。实施设备数据记录 AF 存在/持续时间/负荷的方案有可能有助于改善临床风险分层，应进行前瞻性测试。
