Flecainide acetate

Flecainide作为无选择性Na(+)通道阻断剂，是1C类抗心律失常药，尤其用于室上性心律失常的治疗。Flecainide广泛用于促进长期窦性节律(SR)恢复并减轻房颤症状。

Flecainide能够抑制心Nav1.5钠通道，延长心肌动作电位。Flecainide能够降低完整大鼠心肌细胞的Ca+放电、波动频率和Ca+波速。另外，Flecainide能在I(Na)激活的时候降低Ca(2+)波。有证据表明Flecainide能够显著提高Na(+)/Ca(2+)-交换泵 (NCX)介导的Ca(2+)外流[1]。

Flecainide能够延长心室复极化，在左心室外膜与右心室外膜连接处作用更强。Flecainide作用于心内膜能够比心外膜更能促进有效不应期(ERP)延长，导致穿过心室壁的ERP离散显著增加[2]。

Flecainide剂量依赖性减少全身性压力（0.8 μg/ml时32%）和外围血管压力（0.8 μg/ml时15%）。大鼠后肢灌注模型中，治疗性血浆浓度0.8 μg/ml Flecainide能够显著降低心率（55次/分）并提高QRS间隔（9.9毫秒）[3]。

参考文献：
1. Sikkel MB1, Collins TP, Rowlands C, Shah M, O'Gara P, Williams AJ, Harding SE, Lyon AR, MacLeod KT. Flecainide reduces Ca(2+) spark and wave frequency via inhibition of the sarcolemmal sodium current. Cardiovasc Res. 2013 May 1;98(2):286-96. doi: 10.1093/cvr/cvt012. Epub 2013 Jan 19.
2. Osadchii OE.Flecainide-induced proarrhythmia is attributed to abnormal changes in repolarization and refractoriness in perfused guinea-pig heart. J Cardiovasc Pharmacol. 2012 Nov;60(5):456-66. doi: 10.1097/FJC.0b013e31826b86cf.
3. Allison B1, Yang Y, Pourrier M, Gibson JK. Comparison of the in vivo hemodynamic effects of the antiarrhythmic agents vernakalant and flecainide in a rat hindlimb perfusion model. J Cardiovasc Pharmacol. 2011 Apr;57(4):463-8. doi: 10.1097/FJC.0b013e318210276b.