Adams H R
J Am Vet Med Assoc. 1986 Sep 1;189(5):525-32.
Recent advancements in cardiac pharmacology and physiology have led to the identification of many new antiarrhythmic drugs and a better understanding of basic arrhythmogenic mechanisms. These parallel developments prompted a new nomenclature system for classifying the clinically important antiarrhythmic drugs according to their predominant electrophysiologic actions in cardiac cells. Antiarrhythmic drugs are now grouped into 4 main classes: classes I through IV. Class I agents comprise the standard membrane-stabilizing drugs such as lidocaine, quinidine, and procainamide; newer class I agents include disopyramide, aprindine, tocainide, and flecainide. Class II agents decrease sympathoadrenal excitation of the heart, and the clinically relevant members of this type act through blockade of the cardiac beta 1-adrenergic receptors; propranolol is the prototype. Class III agents selectively prolong the cardiac action potential and refractory period, and bretylium and amiodarone represent this group. Class IV agents are the calcium entry blocking drugs such as verapamil. An understanding of this classification system is essential to the internist and cardiologist who are beset with an emerging array of new antiarrhythmic drugs and affiliated pharmacodynamic terminologies.
心脏药理学和生理学的最新进展已促使人们识别出许多新型抗心律失常药物，并对基本的心律失常机制有了更深入的了解。这些同步发展催生了一种新的命名系统，用于根据临床上重要的抗心律失常药物在心脏细胞中的主要电生理作用对其进行分类。抗心律失常药物现在分为4大类：I类至IV类。I类药物包括标准的膜稳定剂，如利多卡因、奎尼丁和普鲁卡因胺；新型I类药物包括丙吡胺、阿普林定、妥卡尼和氟卡尼。II类药物可降低心脏的交感肾上腺兴奋性，该类中具有临床相关性的药物通过阻断心脏β1肾上腺素能受体发挥作用；普萘洛尔是这类药物的代表。III类药物可选择性延长心脏动作电位和不应期，溴苄铵和胺碘酮属于这一类。IV类药物是钙通道阻滞剂，如维拉帕米。对于面临一系列新出现的抗心律失常药物和相关药效学术语困扰的内科医生和心脏病专家来说，了解这一分类系统至关重要。
