Pedretti R, Colombo E, Sarzi Braga S, Carù B
Division of Cardiology, Clinica del Lavoro Foundation, IRCCS, Medical Center of Rehabilitation, Tradate, Italy.
Am J Cardiol. 1993 Aug 15;72(5):384-92. doi: 10.1016/0002-9149(93)91127-4.
In 41 survivors of acute myocardial infarction (AMI) a prospective study was performed in 2 sequential phases. In phase 1, the role of baroreflex sensitivity and heart rate variability as predictors of inducible and spontaneous sustained ventricular tachyarrhythmias was evaluated. In phase 2, the effects of transdermal scopolamine on baroreflex sensitivity, spectral and nonspectral measures of heart rate variability were investigated. At a mean follow-up of 10 +/- 3 months after AMI, 5 of 41 patients (12%) developed a late arrhythmic event. Of these, all (100%) had inducibility of sustained monomorphic ventricular tachycardia at programmed stimulation compared with 3 of 36 patients (8%) without events (p < 0.0001). At multivariate analysis, baroreflex sensitivity had the strongest relation to both inducibility of sustained monomorphic ventricular tachycardia (p < 0.0001) and occurrence of arrhythmic events (p < 0.0001). Of 41 patients, 28 (68%) consented to undergo phase 2 of the investigation. Baroreflex sensitivity significantly (p < 0.00001) increased after transdermal scopolamine as well as heart rate variability indexes. Of these, the mean of SDs of normal RR intervals for 5-minute segments (p < 0.0001) and the total power (p < 0.0001) had the most significant improvement after scopolamine. The present investigation confirms that assessment of autonomic function is an essential part of arrhythmic risk evaluation after AMI. Transdermal scopolamine, administered to survivors of a recent AMI, reverses the autonomic indexes that independently predict arrhythmic event occurrence. On the basis of these data, transdermal scopolamine could be a potential useful tool in the prophylaxis of life-threatening ventricular arrhythmias after AMI.
在41例急性心肌梗死（AMI）幸存者中进行了一项前瞻性研究，该研究分为两个连续阶段。在第一阶段，评估压力反射敏感性和心率变异性作为诱导性和自发性持续性室性心律失常预测指标的作用。在第二阶段，研究了透皮给予东莨菪碱对压力反射敏感性、心率变异性的频谱和非频谱指标的影响。在AMI后平均随访10±3个月时，41例患者中有5例（12%）发生了晚期心律失常事件。其中，所有发生事件的患者（100%）在程序刺激时可诱发出持续性单形性室性心动过速，而未发生事件的36例患者中有3例（8%）可诱发出该心律失常（p<0.0001）。多因素分析显示，压力反射敏感性与持续性单形性室性心动过速的诱导性（p<0.0001）和心律失常事件的发生（p<0.0001）均具有最强的相关性。41例患者中，28例（68%）同意接受研究的第二阶段。透皮给予东莨菪碱后，压力反射敏感性以及心率变异性指标均显著升高（p<0.00001）。其中，5分钟节段正常RR间期标准差的平均值（p<0.0001）和总功率（p<0.0001）在给予东莨菪碱后改善最为显著。本研究证实，自主神经功能评估是AMI后心律失常风险评估的重要组成部分。对近期AMI幸存者给予透皮东莨菪碱，可逆转独立预测心律失常事件发生的自主神经指标。基于这些数据，透皮东莨菪碱可能是预防AMI后危及生命的室性心律失常的一种潜在有用工具。
