Department of Medicine, Case Western Reserve University, Cleveland, Ohio, USA.
Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA.
J Cardiovasc Electrophysiol. 2024 Jun;35(6):1121-1128. doi: 10.1111/jce.16260. Epub 2024 Mar 27.
Postoperative atrial fibrillation (POAF) is common following open heart surgery, and is associated with significant morbidity. Medications used for ventricular rate control of POAF may not be effective in controlling rapid ventricular rates during the postoperative period because of increased sympathetic tone. The purpose of this study was to develop nonpharmacologic rate control of POAF by atrioventricular node (AVN) fat pad stimulation using clinically available temporary pacing wires in the canine sterile pericarditis model.
We studied 10 sterile pericarditis dogs in the closed-chest state on postoperative days 1-3. The AVN fat pad stimulation (amplitude 2-15 mA; frequency 20 Hz; pulse width 0.03-0.2 ms) was performed during sustained POAF (>5 min). We measured ventricular rate and inefficient ventricular contractions during sustained POAF and compared it with and without AVN fat pad stimulation. Also, the parameters of AVN fat pad stimulation to achieve a rate control of POAF were measured over the postoperative days.
Eleven episodes of sustained POAF were induced in 5/10 sterile pericarditis dogs in the closed-chest state on postoperative days 1-2. During POAF, the AVN fat pad stimulation decreased the ventricular rate from 178 ± 52 bpm to 100 ± 8 bpm in nine episodes. Nonpharmacologic rate control therapy successfully controlled the ventricular rate and eliminated inefficient ventricular contractions during POAF for the duration of the AVN fat pad stimulation. The AVN fat pad stimulation output remained relatively stable over the postoperative days.
During sustained POAF, nonpharmacologic rate control by AVN fat pad stimulation effectively and safely controlled rapid ventricular rates throughout the postoperative period.
心脏直视手术后常发生房性心动过速（POAF），并伴有明显的发病率。由于交感神经张力增加，用于 POAF 心室率控制的药物在术后期间可能无法有效控制快速心室率。本研究的目的是通过在犬无菌性心包炎模型中使用临床可用的临时起搏线来刺激房室结（AVN）脂肪垫，实现 POAF 的非药物性速率控制。
我们在术后第 1-3 天的闭胸状态下研究了 10 只无菌性心包炎犬。在持续 POAF（>5 分钟）期间进行 AVN 脂肪垫刺激（幅度 2-15 mA；频率 20 Hz；脉冲宽度 0.03-0.2 ms）。我们测量了持续 POAF 期间的心室率和无效心室收缩，并将其与有无 AVN 脂肪垫刺激进行了比较。此外，还测量了在术后期间实现 POAF 速率控制的 AVN 脂肪垫刺激参数。
在术后第 1-2 天的闭胸状态下，5/10 只无菌性心包炎犬中诱发了 11 次持续的 POAF。在 POAF 期间，9 次发作中 AVN 脂肪垫刺激将心室率从 178±52 bpm 降低至 100±8 bpm。非药物性速率控制治疗在 AVN 脂肪垫刺激的持续时间内成功地控制了心室率并消除了 POAF 期间的无效心室收缩。AVN 脂肪垫刺激的输出在术后期间相对稳定。
在持续的 POAF 中，通过 AVN 脂肪垫刺激进行的非药物性速率控制可在整个术后期间有效且安全地控制快速心室率。
