Roston Thomas M, Islam Sunjidatul, Hawkins Nathaniel M, Laksman Zachary W, Sanatani Shubhayan, Krahn Andrew D, Sandhu Roopinder, Kaul Padma
Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.
Centre for Cardiovascular Innovation, Division of Cardiology, The University of British Columbia, Vancouver, British Columbia, Canada.
CJC Open. 2021 Sep 14;4(1):65-74. doi: 10.1016/j.cjco.2021.09.006. eCollection 2022 Jan.
Previous studies on lone/unexplained atrial fibrillation and atrial flutter (AF) did not exclude patients with contemporary secondary AF triggers. We characterized unexplained AF using a strict definition, and compared it to secondary AF.
In this population-based study, unexplained AF was defined by the lack of any identifiable triggering medical/surgical diagnosis. Comparisons by AF type (unexplained vs secondary), age-of-onset (≤ / > 65 years), and sex were undertaken. Data were acquired by linking 6 population databases maintained by the Alberta Ministry of Health over a 9-year period (April 2006 to March 2015). The primary composite outcome of stroke, transient ischemic attack, thromboembolism, and/or death was assessed.
There were 33,150 incident AF diagnoses identified, including 1145 patients (3.5%) with unexplained AF, 931 (81.2%) of whom were aged ≤ 65 years (2.8% of diagnoses, and 79% male). Patients with unexplained AF less often received rate/rhythm-control drugs ( < 0.0001), but they more often underwent electrical cardioversion ( < 0.0001) vs secondary AF patients. Men were younger at unexplained AF diagnosis (45 [interquartile range: 34-59] vs 58 [interquartile range: 40-69] years; < 0.001). After adjusting for age at diagnosis, there were no sex-based differences in the primary outcome. Event-free survival in young unexplained AF (age ≤ 65 years) was 99.4% at 1 year and 98.3% at 3 years. At 3 years, hospitalization(s)/emergency visit(s) for noncardiovascular reasons and for AF occurred in 56.6% and 23.8% of these patients, respectively.
Using a strict contemporary definition of unexplained AF, this study shows that the condition is rare, predominantly male, and has excellent event-free survival. However, the high rate of acute hospital utilization after diagnosis is concerning.
既往关于孤立性/不明原因心房颤动和心房扑动（房颤）的研究未排除伴有当代继发性房颤触发因素的患者。我们采用严格定义对不明原因房颤进行了特征描述，并将其与继发性房颤进行比较。
在这项基于人群的研究中，不明原因房颤定义为缺乏任何可识别的触发医学/手术诊断。按房颤类型（不明原因与继发性）、发病年龄（≤/＞65岁）和性别进行比较。通过链接艾伯塔省卫生部维护的6个群体数据库在9年期间（2006年4月至2015年3月）获取数据。评估卒中、短暂性脑缺血发作、血栓栓塞和/或死亡的主要复合结局。
共识别出33150例新发房颤诊断病例，其中1145例（3.5%）为不明原因房颤，其中931例（81.2%）年龄≤65岁（占诊断病例的2.8%，男性占79%）。与继发性房颤患者相比，不明原因房颤患者较少接受心率/节律控制药物治疗（＜0.0001），但更常接受电复律治疗（＜0.0001）。不明原因房颤诊断时男性年龄较轻（45岁[四分位间距：34 - 59岁]对58岁[四分位间距：40 - 69岁]；＜0.001）。在调整诊断年龄后，主要结局无性别差异。年轻不明原因房颤患者（年龄≤65岁）1年时无事件生存率为99.4%，3年时为98.3%。3年时，这些患者分别有56.6%因非心血管原因住院/急诊就诊，23.8%因房颤住院/急诊就诊。
本研究采用严格的当代不明原因房颤定义表明，这种情况罕见，以男性为主，且无事件生存率极佳。然而，诊断后急性住院利用率较高令人担忧。
