*Management of atrial fibrillation (AF): symptom control and prevention of thromboembolism.
For asymptomatic or mildly symptomatic AF patients who are 65 years or older, it is suggested to use a rate-control as opposed to a rhythm-control strategy using medical therapy. This recommendation places a high priority on concerns about side effects of antiarrhythmic drug therapy or radiofrequency catheter ablation. Patients for whom a rhythm-control strategy may be reasonable include those who continue with clinically significant symptoms on a rate-control strategy.
-Calcium channel blockers (verapamil, diltiazem)
-Digoxin may be needed for patients with congestive heart failure. Less likely to control ventricular rate during exercise and does not slow the heart rate in patients with recurrent AF
– IV amiodarone may be needed for patients with poor left ventricular function.
-Catheter ablation as first-line therapy for rhythm control. Patients who may reasonably prefer catheter ablation include younger individuals or those who are concerned about the potential complications of antiarrythmia drugs (AAD).
Recommendations for Catheter ablation:
-For younger patients (age ≤70 years) with symptomatic paroxysmal AF and a LVEF >40% who choose to not receive AAD therapy.
-Patients with symptomatic paroxysmal AF and who have failed or become intolerant to one or more AAD.
-For patients with symptomatic persistent or longstanding persistent AF who have failed or become intolerant of one or more AAD or who choose not to start antiarrhythmic therapy.
*Acute management for new onset AF
-calcium channel blockers such as diltiazem 10mg every 10 minutes is a good first option.
-If that is unsuccessful in resolving the AF, digoxin may be added as second line treatment.
-Amiodarone may be added as third line treatment. Amiodarone can be effective as both an antiarrhythmic as well as for rate control.
*The decision to pursue acute cardioversion is largely dictated by the severity of the patient’s symptoms. In patients with mild to moderate symptoms, with concurrent initiation of the anticoagulation treatment, the initial therapy includes slowing the ventricular rate without an immediate strategy to restore sinus rhythm. Slowing the ventricular rate often results in significant improvement or even resolution of symptoms. Attempts to get the rate below 110 beats per minute should be the initial goal for rate. Four circumstances for which urgent or emergent cardioversion may be needed. They include:
- Active ischemia
- Organ hypoperfusion.
- Severe manifestations of heart failure (HF) i.e. pulmonary edema
- Pre-excitation syndrome, which may lead to an extremely rapid ventricular rate due to the presence of an accessory pathway.
In a patient with any of these indications for urgent cardioversion, the need for restoration of normal sinus rhythm (NSR) takes precedence over the need for protection from thromboembolic risk. IV anticoagulation with heparin should be started, but it should not cause a delay in emergent cardioversion.
-Many patients begun on antiarrhythmic drug therapy should be hospitalized for continuous electrocardiographic monitoring due to a 10 to 15 percent incidence of adverse cardiac events during the initiation of therapy .
-The two complications of greatest concern are bradycardia and proarrhythmia. Other adverse cardiac events can include significant QT prolongation, heart failure, rapid ventricular rate, conduction abnormalities, hypotension, and stroke. The risk is greatest in the first 24 hours and in patients with a prior myocardial infarction.
Outpatient initiation of antiarrhythmic drug therapy with the following agents may be considered:
-Flecainide or propafenone in patients in sinus rhythm who have no underlying structural heart disease, normal baseline QT intervals, and no profound bradycardia or suspected sinus or atrioventricular (AV) node dysfunction.
-Amiodarone or dronedarone in selected patients who have no other risk factors for torsades de pointes (eg, hypokalemia, hypomagnesemia) or sinus node dysfunction or AV conduction disease. Dronedarone and amiodarone are the only two drugs that can be initiated in outpatients while in atrial fibrillation.
-Patients with an implantable cardioverter-defibrillator (ICD) represent another group in which outpatient initiation of therapy can be tried