Supplementary Material for: Vernakalant for Cardioversion of Recent-Onset Atrial Fibrillation in the Emergency Department: The SPECTRUM Study

<b><i>Introduction:</i></b> Intravenous vernakalant is a therapeutic option for symptomatic, recent-onset atrial fibrillation (AF). This secondary analysis from the large SPECTRUM study assessed the safety and effectiveness of vernakalant when used in the emergency department setting (ED group) or in an inpatient hospital setting (non-ED group). <b><i>Methods:</i></b> This post hoc analysis of the international, observational, post-authorization SPECTRUM study included 1,289 and 720 recent-onset AF episodes in adults in the ED and non-ED groups, respectively. Safety endpoints included the evaluation of pre-defined health outcomes of interest (HOIs) and other serious adverse events (SAEs) during vernakalant treatment and during the first 24 h after the last infusion. Effectiveness endpoints comprised the rate of successful vernakalant cardioversion, the time from the start of the vernakalant infusion to cardioversion, and the length of hospital stay. Data were analysed using descriptive statistics. <b><i>Results:</i></b> The safety profile of vernakalant was similar in the ED and non-ED groups. In the ED group, 12 pre-defined HOIs were reported in 11 patients (0.9%); all but one occurred within 2 h after start of the first infusion. These events comprised nine significant bradycardia cases, of which one was associated with transient hypotension and three with sinus arrest, and 2 cases of atrial flutter with 1:1 conduction. Five other SAEs were reported. All patients with vernakalant-related events recovered without sequelae. No Torsade de Pointes, ventricular fibrillation, or deaths occurred. Successful cardioversion was reported in 67.8% (95% confidence interval: 65.2–70.4) and 66.4% (62.5–70.1) of episodes, with a median time to conversion of 11.0 and 10.0 min in the ED and non-ED groups, respectively. Patients had a median length of hospital stay of 7.4 h and 17.1 h in the ED and non-ED groups, respectively. <b><i>Conclusion:</i></b> Intravenous vernakalant was well tolerated with similar cardioversion rates in patients treated in the ED or non-ED setting and does not require admission to a coronary care unit or intensive care unit. First-line treatment with vernakalant could allow an early discharge in patients with recent-onset AF treated in the ED.

引言：静脉用维纳卡兰（vernakalant）是有症状的新发心房颤动（atrial fibrillation, AF）的治疗选择之一。本次针对大型SPECTRUM研究的二次分析，评估了维纳卡兰在急诊科室（emergency department, ED）环境（急诊组）与住院病房环境（非急诊组）中使用时的安全性与有效性。
方法：本研究为国际性、观察性、上市后SPECTRUM研究的事后分析，共纳入成人新发心房颤动发作事件共2009例，其中急诊组1289例，非急诊组720例。安全性终点包括评估维纳卡兰治疗期间及末次输注后前24小时内的预先指定的关注健康结局（health outcomes of interest, HOIs）以及其他严重不良事件（serious adverse events, SAEs）。有效性终点包括维纳卡兰电复律的成功率、从开始输注维纳卡兰至复律的时间，以及住院时长。数据采用描述性统计学方法进行分析。
结果：维纳卡兰在急诊组与非急诊组的安全性特征相似。急诊组中，11例患者（占比0.9%）报告了12项预先指定的关注健康结局，其中仅1例事件发生在首次输注开始后2小时之外。这些事件包括9例显著心动过缓，其中1例伴短暂低血压，3例伴窦性停搏，以及2例伴1:1传导的心房扑动。另有5例严重不良事件报告。所有出现维纳卡兰相关不良事件的患者均完全康复，无后遗症。未观察到尖端扭转型室性心动过速（Torsade de Pointes）、心室颤动或死亡病例。急诊组与非急诊组的复律成功率分别为67.8%（95%置信区间：65.2~70.4）与66.4%（62.5~70.1），两组的中位复律时间分别为11.0分钟与10.0分钟。急诊组与非急诊组患者的中位住院时长分别为7.4小时与17.1小时。
结论：静脉用维纳卡兰耐受性良好，在急诊与非急诊环境下接受治疗的患者的复律率相似，且无需收入冠心病监护病房或重症监护病房。对于在急诊接受治疗的新发心房颤动患者，采用维纳卡兰作为一线治疗可实现早期出院。