Antiarrythmic Drugs

Front 1

Describe the distinguishing features of the five major groups of antiarrhythmic drugs with respect to mechanism of action pharmacokinetics, clinical uses, effects on the ECG, and toxicity.

Back 1

Too much to list

Front 2

List two or three of the most important drugs in each of the five groups.

Back 2

Class 1:
a - amiodarone (procainimide, quinidine)
b - lidocaine
c- flecainide

Class 2: propranolol (esmolol, sotalol, amiodarone)

Class III: Ibutilide (sotalol, amiodarone)

Class IV: Verapamil (diltiazem)

Miscellaneous: Adenosine, K+, Mg2+

Front 3

Describe the primary research question and conclusion of the CAST antiarrhythmic drug trials

Back 3

Observation: Patients who suffer an MI and have ectopic ventricular beats (PVCs) are are risk for sudden death due to ventricular fibrillation.

Question: Treatment of Class 1c antiarrhythmic flecainide to prevent PVCs and thereby reduce the risk of sudden death.

Results: very effective at reducing PVCs, but set up arryhthmias as well --> patients taking Sodium channel blockers (flecainide) as a preventative measure actually had 2-3x higher mortality rate.

Conclusion: long term antiarrhythmics other than B-blockers and Amiodarone should not be used unless patients have preexisting or sustained symptomatic arrhythmias; reducing PVCs is NOT the same as reducing sudden death in these patients; the advances in implantable defibrillators (ICD) has shifted treatment away from using long-term antiarrhythmics.

Front 4

Describe the primary research question and conclusion of the AFFIRM antiarrhythmic drug trials

Back 4

Observation: Atrial flutter and Atrial fibrillation are most common sustained arrythmias and rate control is important for all supraventricular arrhythmias to protect ventricles from dangerous pacing.

Question: Rate control vs. Rhythm control --> does rhythm control provide a benefit for treating supraventricular arrhythmias?
- rhythm control requires long-term treatment with class 1/class3 drugs

Conclusion: rhythm control offered no advantages over rate control with respect to mortality or CV events; both rate and rhythm control require anticoagulant drugs to prevent thrombus formation and stroke; rhythm control drugs have higher drug toxicity.