Mitchell L B, Schroeder J S, Mason J W
Am J Cardiol. 1982 Feb 18;49(3):629-35. doi: 10.1016/s0002-9149(82)80022-2.
The slow channel blocking agents--diltiazem, verapamil and nifedipine--have generated clinical interest for the treatment of a variety of cardiovascular disorders. These agents, despite a similar basic mechanism of action, produce disparate clinical cardiac electrophysiologic effects in human beings. In usual doses, the acute administration of diltiazem slows heart rate. Verapamil and nifedipine, however, increase heart rate. Although diltiazem and verapamil produce equivalent slowing of atrioventricular (A-V) nodal conduction, verapamil prolongs A-V nodal refractoriness to a greater degree. In contrast, nifedipine facilitates A-V nodal conduction and shortens A-V nodal refractoriness. Knowledge of these differences may aid in the appropriate selection of specific slow channel blocking agents in specific clinical situations.
慢通道阻滞剂——地尔硫䓬、维拉帕米和硝苯地平——已引起临床关注，用于治疗多种心血管疾病。尽管这些药物的基本作用机制相似，但在人体中会产生不同的临床心脏电生理效应。通常剂量下，急性给予地尔硫䓬会使心率减慢。然而，维拉帕米和硝苯地平会使心率加快。虽然地尔硫䓬和维拉帕米使房室（A-V）结传导减慢的程度相当，但维拉帕米使A-V结不应期延长的程度更大。相比之下，硝苯地平促进A-V结传导并缩短A-V结不应期。了解这些差异可能有助于在特定临床情况下适当选择特定的慢通道阻滞剂。
