Atrial fibrillation

First-line ablation

There seems to be a growing concensus that catheter ablation (CA) should be used as a "first-line" treatment for AF in preference to antiarrhythmic drugs (AADs). It seems that AADs are not very effective in preventing AF (maintaining sinus rhythm), and their adverse effects are as bad as those of AF (although different).

There are lots of papers and articles on the topic - some are listed below:

Drugs

See NHS treatments for atrial fibrillation and  NICE prescribing information for atrial fibrillation.

Rhythm control drugs

Flecainide

This interacts with fludrocortisone: predicted to cause hypokalaemia (potentially increasing the risk of torsade de pointes) (Severity: severe).

Sotalol

This interacts with fludrocortisone: predicted to cause hypokalaemia (potentially increasing the risk of torsade de pointes) (Severity: severe).

Also, since it's a beta-blocker, hypotension and marked bradycardia are both contra-indications.

Amiodarone

This interacts with fludrocortisone: predicted to cause hypokalaemia (potentially increasing the risk of torsade de pointes) (Severity: severe).

Other beta blockers

Hypotension and marked bradycardia are both contra-indications for all beta-adrenoceptor blockers (systemic). These include all the beta-blockers licensed in the UK for atrial fibrillation: i.e. atenolol, acebutolol, metoprolol, nadolol, oxprenolol and propranolol. It also includes bisoprolol, which is listed on the NHS website.

Rate limiting drugs

According to the NHS "The aim is to reduce your heart rate to less than 90 beats per minute when you are resting", so they shouldn't be considered relevant.

Diltiazem

This is a calcium-channel blocker. Severe bradycardia is a contra-indication. Both Diltiazem and Alcohol can increase the risk of hypotension.

Verapamil

This is a calcium-channel blocker. Bradycardia and hypotension are both contra-indications. Verapamil slightly increases the exposure to Edoxaban.

Diltiazem and verapamil

This Nice page lists further information about contra-indications for these drugs:

Digoxin

This is a cardiac glycoside. Interaction: Fludrocortisone is predicted to increase the risk of Digoxin toxicity when given with Digoxin (Severity: severe).


Glossary

Definitions from Collins dictionary.

EmbolismA serious medical condition that occurs when an artery becomes blocked, usually by a blood clot.
EmbolusMaterial, such as part of a blood clot or an air bubble, that is transported by the bloodstream until it becomes lodged within a small vessel and impedes the circulation.
FibrinA white insoluble elastic protein formed from fibrinogen when blood clots: forms a network that traps red cells and platelets.
FibrinolysisThe breakdown of fibrin in blood clots, esp by enzymes.
IschaemiaAn inadequate supply of blood to an organ or part, as from an obstructed blood flow.
PlasminA proteolytic enzyme that causes fibrinolysis in blood clots.
PlateletPlatelets are a kind of blood cell. If you cut yourself and you are bleeding, platelets help to stop the bleeding.
ThrombinAn enzyme that acts on fibrinogen in blood causing it to clot.
ThrombosisThe formation of a blood clot in a person's heart or in one of their blood vessels, which can cause death.
ThrombusA clot of coagulated blood that forms within a blood vessel or inside the heart and remains at the site of its formation, often impeding the flow of blood.