A Simple Guide To Atrial Fibrillation II

A Simple Guide To Atrial Fibrillation II
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What is the Complications of Atrial Fibrillation?
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1.fibrosis of the atria

2.Enlarged atria and heart

3.Thrombosis to the brain(stroke),
intestines(ischemia),
fingers and toe(ischemia or gangrene)


What is the Treatment of Atrial Fibrillation?
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The treatment of atrial fibrillation is aimed at

1.regulating the heart beat and rhythm- digoxin, dilatrend, betablockers

2.preventing blood clots to be thrown out in the blood stream -anticoagulants

3.In cases of uncontrolled tachycardia, immediate cardioversion may be done.

Regulating the heart beat:
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a.rate control

Rate control is by drugs to reduce the heart rate to 60 to 100 bpm without changing to a regular rhythm.

The medications work by blocking the AV node reducing the electrical impulses to the ventricles.

1.Beta blockers such as metoprolol, atenolol, bisoprolol

2.Cardiac glycosides ( digoxin)

3.Calcium channel blockers (i.e. diltiazem or verapamil)

4.amiodarone has AV node blocking effects which can be used when other agents are contraindicated (eg.hypotension).

b.rhythm control

Rhythm control work to restore the regular heart rhythm and maintain it with drugs.

The anti-arrhythmic medications makes the heart tissue less excitable.
These medications are often used in concert with electrical cardioversion.

Prevention of blood clots in blood stream:
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Anticoagulation with drugs as below reduce the risk of blood clots being thrown out from the heart and blocking the passage of blood in the arteries of the heart or brain

1.aspirin

2.clopidogrel in those who are allergic to aspirin

3.warfarin or similar drugs.

4.heparin intravenously prevents blood clotting in urgent cases.

Cardioversion
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Cardioversion is the conversion of an abnormal heartbeat to a normal heartbeat using electrical or chemical means

1.Electrical cardioversion restores the heart rhythm by appying a DC electrical shock to the heart.

2.Chemical cardioversion uses medicine such as amiodarone, dronedarone, procainamide, ibutilide, propafenone or flecainide.

Cardioversion should not be done unless adequate anticoagulation has been given to patients for 48 hours.

There is a relapse rate of 1% following cardioversion.

3.Catheter ablation
It is possible to destroy the bundle of cells connecting the upper and lower chambers of the heart - the atrioventricular node - which regulates heart rate, and to implant a pacemaker Another method involves ablating groups of cells near the pulmonary veins where atrial fibrillation is thought to originate.This method do not need a pacemaker.

4. Radiofrequency ablation uses radiofrequency energy to remove abnormal electrical pathways in heart tissue.

5. laser, cryothermy and high intensity ultrasound has been use to eliminate the responsible heart tissue causing the irregular heart beats.

Surgical Maze procedure
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A series of incisions is made in the atriain a maze-like pattern.
This block abnormal electrical circuits that AF requires.

Minimaze surgery is a minimally invasive cardiac surgery that do not require a median sternotomy or cardiopulmonary bypass.

Laser, cryothermy, radiofrequency, or acoustic energy are used to destroy atrial tissue near the pulmonary veins and and other ablations to mimic the maze.

What is the prognosis of Atrial Fibrillation?
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Most cases of patients treated with rate control and cardioversion with ablation has excellent prognosis, usually better than those with rhthym control.

Recurrence may recur especially if there is an underlying condition which cannot be cured.

What are the prevention measures for Atrial Fibrillation?
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Rest and a healthy lifestyle may help to prevent an onset or recurrence of atrial fibrillation.

Avoid stress and anxiety.