(FIT)-Module 4 Lectures: Non-Invasive Diagnosis and Treatment-Antiarrhythmic Drugs, Part 1 (Poole)

Video Transcription

Video Summary

In this presentation, Jeannie Poole discusses antiarrhythmic drugs, specifically focusing on their mechanisms of action, clinical use, metabolism, and drug interactions. The presentation primarily uses the Vaughn-Williams classification to categorize these drugs, noting the primary action of each class. Class I drugs, such as quinidine and lidocaine, act as sodium channel blockers, while Class III, including sotilol and dofetilide, are potassium channel blockers. Detailed descriptions of classes I and III drugs include their usage, indications, and associated precautions, like their effects on action potentials and potential side effects such as QT prolongation and torsades de pointes. The presentation also highlights contraindications, particularly in patients with coronary disease and heart failure, tracing back to clinical trials such as the CAST trial for class I drugs. Furthermore, the session covers pharmacogenetics, metabolism factors like cytochrome P450 isozymes, bioavailability, and the role of P-glycoprotein in drug absorption. Complexities such as the pharmacokinetics, use-dependence of sodium channel blockers, and reverse use-dependence of potassium blockers are also reviewed. The presentation concludes by offering additional study resources, including bibliographical data from clinical trials and pharmacological tables.

Keywords

antiarrhythmic drugs

Vaughn-Williams classification

Class I sodium channel blockers

Class III potassium channel blockers

QT prolongation

torsades de pointes

pharmacogenetics

cytochrome P450 metabolism