Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
Equine Cardioteam, Department of Large Animal Internal Medicine, Ghent University, Merelbeke, Belgium.
Equine Vet J. 2022 Nov;54(6):1013-1022. doi: 10.1111/evj.13551. Epub 2022 Jan 13.
The recurrence rate of atrial fibrillation (AF) in horses after cardioversion to sinus rhythm (SR) is relatively high. Atrial fibrillatory rate (AFR) derived from surface ECG is considered a biomarker for electrical remodelling and could potentially be used for the prediction of successful AF cardioversion and AF recurrence.
Evaluate if AFR was associated with successful treatment and could predict AF recurrence in horses.
Retrospective multicentre study.
Electrocardiograms (ECG) from horses with persistent AF admitted for cardioversion with either medical treatment (quinidine) or transvenous electrical cardioversion (TVEC) were included. Bipolar surface ECG recordings were analysed by spatiotemporal cancellation of QRST complexes and calculation of AFR from the remaining atrial signal. Kaplan-Meier survival curve and Cox regression analyses were performed to assess the relationship between AFR and the risk of AF recurrence.
Of the 195 horses included, 74 received quinidine treatment and 121 were treated with TVEC. Ten horses did not cardiovert to SR after quinidine treatment and AFR was higher in these, compared with the horses that successfully cardioverted to SR (median [interquartile range]), (383 [367-422] vs 351 [332-389] fibrillations per minute (fpm), P < .01). Within the first 180 days following AF cardioversion, 12% of the quinidine and 34% of TVEC horses had AF recurrence. For the horses successfully cardioverted with TVEC, AFR above 380 fpm was significantly associated with AF recurrence (hazard ratio = 2.4, 95% confidence interval 1.2-4.8, P = .01).
The treatment groups were different and not randomly allocated, therefore the two treatments cannot be compared. Medical records and the follow-up strategy varied between the centres.
High AFR is associated with failure of quinidine cardioversion and AF recurrence after successful TVEC. As a noninvasive marker that can be retrieved from surface ECG, AFR can be clinically useful in predicting the probability of responding to quinidine treatment as well as maintaining SR after electrical cardioversion.
心房颤动（AF）在电复律转为窦性节律（SR）后的复发率相对较高。体表心电图得出的心房颤动率（AFR）被认为是电重构的生物标志物，可能可用于预测 AF 电复律的成功和 AF 复发。
评估 AFR 是否与治疗成功相关，并可预测马 AF 的复发。
回顾性多中心研究。
纳入因 AF 持续而接受药物（奎尼丁）或经静脉电复律（TVEC）转复的持续性 AF 马的心电图（ECG）。通过 QRST 复合体的时空消除和剩余心房信号计算 AFR 对双极体表 ECG 记录进行分析。采用 Kaplan-Meier 生存曲线和 Cox 回归分析评估 AFR 与 AF 复发风险之间的关系。
在纳入的 195 匹马中，74 匹马接受了奎尼丁治疗，121 匹马接受了 TVEC 治疗。10 匹马在接受奎尼丁治疗后未转为 SR，与成功转为 SR 的马相比，这些马的 AFR 更高（中位数[四分位距]）（383[367-422]vs 351[332-389]次/分钟，P<.01）。在 AF 电复律后的头 180 天内，12%的奎尼丁和 34%的 TVEC 马出现 AF 复发。对于 TVEC 成功复律的马，AFR 高于 380 次/分钟与 AF 复发显著相关（风险比=2.4，95%置信区间 1.2-4.8，P=.01）。
治疗组不同，且未随机分配，因此不能对两种治疗方法进行比较。各中心的病历和随访策略存在差异。
高 AFR 与奎尼丁转复失败和 TVEC 成功后 AF 复发相关。作为一种可从体表 ECG 获得的非侵入性标志物，AFR 可在预测对奎尼丁治疗的反应概率以及在电复律后维持 SR 方面具有临床应用价值。
