Classify anti-arrhythmic drugs by mechanism of action, giving examples of each (75% of marks). Describe the electrophysiological and ECG effects of sotalol (25% of marks).
Most answers displayed a good knowledge of the Vaughan Williams classification, classes I to
IV and the relevant electrophysiological characteristics of the classes.
Answers should also have included mention of other antiarrhythmics, such as digoxin,
magnesium and adenosine. The second part of the question required comment about K ion
blockade and its effects. It was helpful to mention prolongation of QT and risk of torsade. Most
answers omitted reference to its being a racemic mixture, with different actions of the isomers.