Salerno D M, Murakami M M, Johnston R B, Keyler D E, Pentel P R
Division of Cardiology, Hennepin County Medical Center, University of Minnesota, Minneapolis, USA.
Am J Emerg Med. 1995 May;13(3):285-93. doi: 10.1016/0735-6757(95)90201-5.
Flecainide occasionally produces incessant ventricular tachycardia that is difficult to treat. Reports of uncontrolled clinical studies have suggested a therapeutic role for hypertonic sodium bicarbonate (NaHCO3). To test this observation, spontaneous and pacing-induced arrhythmia canine models were designed. In the spontaneous model, flecainide was infused at 0.5 mg/kg/min until ventricular tachycardia occurred spontaneously. In the pacing-induced model, flecainide was infused at 1.0 mg/kg/min load (0.5 mg/kg/min maintenance) stepwise until the QRS was widened 50%, 75%, and 100%, with programmed ventricular stimulation at each step until ventricular arrhythmia was induced. Dogs who developed spontaneous arrhythmia were treated blindly with three doses of either NaHCO3 (3 mEq/kg/dose, with 1 minute between doses) or normal saline. Dogs who were induced in the second model were treated with the same three doses, 10 minutes apart, with programmed stimulation between each dose. Before unblinding in both protocols, dogs were classified as "responders" or "nonresponders" to therapy. In the spontaneous model, of 14 dogs with spontaneous ventricular tachycardia, all 7 dogs treated with NaHCO3 showed response, compared with only 1 of 7 dogs treated with saline (P < .01). Ventricular QRS complexes/min were reduced by NaHCO3 in that protocol. In the induced arrhythmia protocol, of 14 dogs with inducible arrhythmia, 6 of 7 responded to NaHCO3, and 1 of 7 responded to placebo (P < .05). In both protocols, arterial pH and the serum sodium concentration were increased by NaHCO3 but not by normal saline control treatment. QRS interval duration was shortened by NaHCO3 therapy.(ABSTRACT TRUNCATED AT 250 WORDS)
氟卡尼偶尔会引发难以治疗的持续性室性心动过速。非对照临床研究报告提示高渗碳酸氢钠（NaHCO₃）可能具有治疗作用。为验证这一观察结果，设计了自发性和起搏诱导性心律失常犬模型。在自发性模型中，以0.5毫克/千克/分钟的速度输注氟卡尼，直至自发性室性心动过速发生。在起搏诱导性模型中，以1.0毫克/千克/分钟的负荷量（0.5毫克/千克/分钟维持量）逐步输注氟卡尼，直至QRS波增宽50%、75%和100%，每一步均进行程控心室刺激，直至诱发室性心律失常。出现自发性心律失常的犬只被随机给予三剂NaHCO₃（3毫当量/千克/剂，剂间间隔1分钟）或生理盐水进行盲法治疗。在第二个模型中诱发心律失常的犬只，以相同的三剂进行治疗，剂间间隔10分钟，每剂之间进行程控刺激。在两种方案解除盲法之前，将犬只分为治疗“反应者”或“无反应者”。在自发性模型中，14只发生自发性室性心动过速的犬只中，接受NaHCO₃治疗的7只犬均有反应，而接受生理盐水治疗的7只犬中只有1只出现反应（P <.01）。在该方案中，NaHCO₃使心室QRS波群每分钟次数减少。在诱发性心律失常方案中，14只可诱发心律失常的犬只中，7只接受NaHCO₃治疗的犬有6只出现反应，7只接受安慰剂治疗的犬有1只出现反应（P <.05）。在两种方案中，NaHCO₃均可使动脉血pH值和血清钠浓度升高，而生理盐水对照治疗则无此作用。NaHCO₃治疗可缩短QRS间期持续时间。（摘要截短于250字）
