School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom.
School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom.
Heart Rhythm. 2019 May;16(5):702-709. doi: 10.1016/j.hrthm.2018.11.013. Epub 2018 Dec 5.
Enhanced beat-to-beat variability of repolarization is strongly linked to arrhythmogenesis and is largely due to variation in ventricular action potential duration (APD). Previous studies in humans have relied on QT interval measurements; however, a direct relationship between beat-to-beat variability of APD and arrhythmogenesis in humans has yet to be demonstrated.
This study aimed to explore the beat-to-beat repolarization dynamics in patients with heart failure at the level of ventricular APD.
Forty-three patients with heart failure and implanted cardiac resynchronization therapy - defibrillator devices were studied. Activation-recovery intervals as a surrogate for APD were recorded from the left ventricular epicardial lead while pacing from the right ventricular lead to maintain a constant cycle length.
During a mean follow-up of 23.6±13.6 months, 11 patients sustained ventricular fibrillation/ventricular tachycardia (VT/VF) and received appropriate implantable cardioverter-defibrillator therapies (antitachycardia pacing or shock therapy). Activation-recovery interval variability (ARIV) was significantly greater in patients with subsequent VT/VF than in those without VT/VF (3.55±1.3 ms vs 2.77±1.09 ms; P=.047). Receiver operating characteristic curve analysis (area under the curve 0.71; P=.046) suggested high- and low-risk ARIV groups for VT/VF. Kaplan-Meier survival analysis demonstrated that the time until first appropriate therapy for VT/VF was significantly shorter in the high-risk ARIV group (P=.028). ARIV was a predictor for VT/VF in the multivariate Cox model (hazard ratio 1.623; 95% confidence interval 1.1-2.393; P=.015).
Increased left ventricular ARIV is associated with an increased risk of VT/VF in patients with heart failure.
复极的逐搏变异性增强与心律失常发生密切相关，主要是由于心室动作电位时程（APD）的变化。以前的人类研究依赖于 QT 间期测量；然而，人类 APD 的逐搏变异性与心律失常之间的直接关系尚未得到证明。
本研究旨在探讨心力衰竭患者在心室 APD 水平的逐搏复极动力学。
研究了 43 例植入心脏再同步治疗除颤器的心力衰竭患者。从左心室心外膜导联记录激活后恢复间期作为 APD 的替代指标，同时从右心室导联起搏以保持恒定的心动周期长度。
在平均 23.6±13.6 个月的随访期间，11 例患者发生室颤/室性心动过速（VT/VF）并接受了适当的植入式心脏复律除颤器治疗（抗心动过速起搏或电击治疗）。随后发生 VT/VF 的患者的激活后恢复间期变异性（ARIV）明显大于未发生 VT/VF 的患者（3.55±1.3 ms 与 2.77±1.09 ms；P=.047）。ROC 曲线分析（曲线下面积 0.71；P=.046）提示 ARIV 高、低危 VT/VF 组。Kaplan-Meier 生存分析表明，高危 ARIV 组首次适当 VT/VF 治疗的时间明显缩短（P=.028）。在多变量 Cox 模型中，ARIV 是 VT/VF 的预测因子（危险比 1.623；95%置信区间 1.1-2.393；P=.015）。
心力衰竭患者左心室 ARIV 增加与 VT/VF 风险增加相关。
