心房颤动患者经静脉体内电复律术后早期心房颤动复发及电生理机制的研究

Early reccurence of atrial fibrillation after transvenous atrial defibrillation

目的观察经体内低能量心房颤动（房颤）除颤术后不同电生理参数与房颤早期复发的关系。方法对４２例（男３０例，女１２例），平均年龄（６０±１１）岁的慢性房颤患者行经静脉体内Ｒ波同步双相电波除颤术并转为窦性心律后，有１２例（２９％）发生房颤早期复发（２分钟内）。对房颤早期复发患者和窦律维持患者的Ｐ波时限、房性早搏（房早）密度、房早耦联间期等进行了测量与分析。结果１２例房颤早期复发患者共５３次成功转复窦律过程中，窦性心律平均维持（１９．０±１７．３）秒。该组患者房早密度为（８．７±１１．９）次／ｍｉｎ。与成功维持窦律者（２．５±２．２）次／ｍｉｎ相比，房早密度差异有极显著性（Ｐ＜０．００１）。结论经静脉体内低能量房颤转复是有效复律方法，但房颤早期复发仍是待解决的问题之一。房早密度可作为预计房颤早期复发的指标。强调除颤后抑制房早措施对预防房颤早发具有重要性。

Objective In patients with atrial fibrillation (AF), restoration of sinus rhythm offers both hemodynamic and thromboembolic control, but may be limited by early recurrence of AF (ERAF) after external or transvenous atrial defibrillation (TAD). The purpose of this study was to assess the predictive value of some electrophysiological parameters for ERAF. Methods Forty two consecutive patients (30 males, 12 females, age 60±11 years) with AF underwent low energy TAD using R wave synchronized biphasic shocks delivered from a custom external atrial defibrillator with step up energy up to 400 Volts.Results Successful termination of AF by TAD was achieved in all patients. However, ERAF(defined as spontaneous reinitiation of AF within 2 minutes after successful cardioversion) was observed in 12 patients (29%). Atrial premature contraction (APC) density (defined as the number of APCs divided by the duration of sinus rhythm up to 2 minutes) was calculated and coupling time of APCs was measured for patients with ERAF and for those without. The mean duration for 53 episodes of sinus rhythm in 12 patients with ERAF was 19.0±17.3 seconds. Patients with ERAF had significantly higher APC density than those without (8.7±11.9/min vs 2.5±2.2/min, P <0.001).Conclusion TAD is effective in converting AF to sinus rhythm, but ERAF occurs about 30% in patients with chronic AF. APC density may be used as a predictor for ERAF and failure of restoration of sinus rhythm. The findings of this study indicate that APC suppression, either by electrical pacing and/or pharmacological intervention, may be necessary for maintenance of sinus rhythm after cardioversion.