oxyfedrine and Bradycardia

Topics: Adrenergic beta-Antagonists; Bradycardia; Chronic Disease; Coronary Disease; Humans; Nitroglycerin; Oxyfedrine

Topics: Adult; Aged; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Atrial Fibrillation; Bradycardia; Drug Evaluation; Female; Heart Block; Heart Conduction System; Humans; Male; Middle Aged; Oxyfedrine; Propiophenones

The electrophysiological effects of Oxyfedrine on sino-atrial function and on A-V junctional and subjunctional conduction have been studied in 16 patients with sinus node and/or atrial dysrhythmias. The following effects have been observed: --a positive chronotropic effect on the sinus node; --an essentially indirect (rate-dependent) shortening of the Functional and Effective Refractory Periods (FRP and ERP) of the atria without variation of the Intra-Atrial Conduction Time (HRA-LRA). There was no significant shortening of the Maximal Atrial Latency (max AL), of the Corrected Sinus Node Recovery Time (CSNRT) and of the Sino-Atrial Conduction Time (SACT). The limits of Zones I, II, III of the sinus node response to atrial extra-stimuli were reduced with no significant change in their duration, expressed as percentage of the Sinus Cycle Length (SCL); --an improvement in the A-V junctional conduction (shortening of the A-H interval for comparable cycle lengths) due to a relatively shortened A-V junctional ERP. The use of the drug in patients with sinus bradycardia and/or atrial dysrhythmias and conduction disturbances, is proposed.

Topics: Adult; Aged; Bradycardia; Drug Evaluation; Electrocardiography; Female; Heart Block; Humans; Male; Middle Aged; Oxyfedrine; Propiophenones; Sinoatrial Block; Sinoatrial Node; Time Factors

Topics: Adrenal Cortex Hormones; Anti-Arrhythmia Agents; Atropine; Bradycardia; Glucagon; Humans; Isoproterenol; Metaproterenol; Oxyfedrine