MedifocusHealth

All patients with atrial fibrillation should be anticoagulated unless there is a definite contraindication. They are usually started on heparin and then warfarin (Coumadin) is given orally. Coumadin is given with the aim of achieving an international normalized ratio (INR) of 2 to 3.

Rate Control

As noted previously, one acceptable strategy for the management of patients with paroxysmal or persistent atrial fibrillation is to control the ventricular rate to 60-80 beats per minute at rest or 90-115 beats per minute during moderate exercise. This strategy is known as rate control.

A variety of pharmacological agents (medications) can be used to control the ventricular rate in patients with atrial fibrillation including:

• Calcium channel blockers

  • verapamil (e.g., Verelan)
  • diltiazem (e.g., Cardizem)

• Beta blockers

  • propranolol (e.g., Inderal)
  • sotalol (e.g., Betapace AF)
  • metoprolol (e.g., Lopressor)
  • atenolol (e.g., Tenormin)
  • acebutolol (e.g., Sectral)
  • esmolol (e.g., Brevibloc)
  • carvedilol (e.g., Coreg)

• Digoxin (e.g., Lanoxin)

In April 2008, Actavis Totowa LLC, the manufacturer of Digitek (digoxin tablets, USP) notified healthcare professionals of a Class I nationwide recall of the product due to the possibility that tablets with double the appropriate thickness may contain twice the approved level of active ingredient. The existence of double strength tablets poses a risk of digitalis toxicity in patients with kidney failure. Digitalis toxicity can cause nausea, vomiting, dizziness, low blood pressure, cardiac instability, and bradycardia. Patients are urged to contact their healthcare provider with any questions regarding Digitek.

• Amiodarone (e.g., Corderone)

In general, calcium channel blockers and beta blockers are the first-choice agents for rate control, however, digoxin and amiodarone may also be used. Digoxin is usually the first choice in patients with persistent atrial fibrillation with concurrent congestive heart failure or left ventricular dysfunction.

For patients with atrial fibrillation whose ventricular rate cannot be adequately controlled with medications or patients who experience adverse side-effects from these medications, an alterative strategy is atrioventricular (AV) nodal ablation with permanent implantation of a pacemaker. In general, this approach is effective in controlling the ventricular rate and usually leads to an improvement in symptoms such as decreased incidence of palpitations, shortness of breath, dizziness, and fatigue. Disadvantages of this treatment modality include:

• Need for continuous anticoagulation medications
• Lifetime dependency on a pacemaker
• Potential risks and complications associated with the surgical implantation of a pacemaker.

Rhythm Control

An alternative strategy that may be used in the management of patients with atrial fibrillation is rhythm control. The goal of rhythm control is to convert the patient from a state of atrial fibrillation back to normal sinus rhythm. Depending upon a variety of factors, rhythm control may be accomplished with either medications, a strategy known as pharmacological cardioversion, or with electrical shocks, an approach known as electrical cardioversion.

Pharmacological Cardioversion

Pharmacological agents used for conversion of patients with atrial fibrillation back to normal sinus rhythm (pharmacological cardioversion) are called antiarrhythmic medications and are classified as Vaughn-William class IC, class III, or class IA antiarrhythmics.