Heissenbuttel R H, Bigger J T
Ann Intern Med. 1979 Aug;91(2):229-38. doi: 10.7326/0003-4819-91-2-229.
Bretylium tosylate (Bretylol) has recently been approved for parenteral use against resistant ventricular arrhythmias. The pharmacologic action of bretylium is complex, and its antiarrhythmic action differs significantly from other drugs. Bretylium is an adrenergic neuronal blocking agent taken up selectively at peripheral adrenergic nerve terminals, where it initially releases norepinephrine (sympathomimetic effect) and then produces adrenergic neuronal blockade. It has direct cardiac membrane effect to prolong action potential duration and effective refractory period but, unlike other membrane active antiarrhythmic agents, does not depress conduction velocity or automaticity. Bretylium increases ventricular fibrillation threshold and prevents the decrease in ventricular fibrillation threshold associated with myocardial ischemia. It does not depress myocardial contractility. Clinical studies have shown parenteral bretylium to be effective in suppressing ventricular arrhythmias, particularly recurrent, drug resistant ventricular tachycardia or ventricular fibrillation.
溴苄铵（Bretylol）最近已被批准用于胃肠外给药，以治疗难治性室性心律失常。溴苄铵的药理作用复杂，其抗心律失常作用与其他药物有显著差异。溴苄铵是一种肾上腺素能神经阻滞剂，可在外周肾上腺素能神经末梢被选择性摄取，在那里它最初释放去甲肾上腺素（拟交感神经效应），然后产生肾上腺素能神经阻滞作用。它具有直接的心脏膜效应，可延长动作电位持续时间和有效不应期，但与其他膜活性抗心律失常药物不同，它不会降低传导速度或自律性。溴苄铵可提高心室颤动阈值，并防止与心肌缺血相关的心室颤动阈值降低。它不会抑制心肌收缩力。临床研究表明，胃肠外给药的溴苄铵在抑制室性心律失常方面有效，尤其是复发性、耐药性室性心动过速或心室颤动。
