Case #1 Answers:

Awaiting answer review













Answer 1
Ventricular response is determined by AV conduction system, usually AV node rather than His-Purkinje is limiting factor. Factors affecting this include sympathetic/parasympathetic tone, circulating catecholamines, and medications. Other modifying factors in general may be metabolic derangements, fever, illicit drugs, and thyroid status.












Answer 2
History: Assess ETOH use, sx of thyroid disease, prior BP readings, GI bleeding.

Tests: CBC, CMP, TSH, possibly INR. Echo to exclude SHD.












Answer 3
Rate vs rhythm control vs prn management, depends on severity and frequency of sx.













Answer 4
Rate control could be with a Beta Blocker or Calcium Blocker with negative chronotropic effects. Digoxin in this high catecholamine state would not be effective.












Answer 5
No, but duration suggests need for 3-4 weeks of anticoagulation before and after, and/or TEE. Could consider electrical or chemical conversion.













Answer 6
Low risk for thromboembolism and ASA (or nothing) is adequate long term.













Answer 7
Antiarrhythmic drug tx could be daily or possibly a "pill in pocket" approach may suffice depending on frequency, severity. May be candidate for Class Ic or III agent. Ischemia, hepatic or renal dysfunction should be excluded. Amiodarone would be a second or third line agent in this setting. AF ablation should also be considered if he fails at least one antiarrhythmic drug, is intolerant, or prefers to avoid a long term antiarrhythmic agent.