The main goals of treatment are to prevent
circulatory instability and
stroke. Rate or rhythm control is used to achieve the former, whereas
anticoagulation is used to decrease the risk of the latter. If cardiovascularly unstable due to uncontrolled
tachycardia, immediate
cardioversion is indicated. An integrated management approach, which includes stroke prevention, symptoms control and management of associated comorbidities has been associated with better outcomes in patients with atrial fibrillation. This holistic or integrated care approach is summed up as the ABC (Atrial fibrillation Better Care) pathway, as follows: • A: Avoid stroke with Anticoagulation, where the default is stroke prevention unless the patient is at low risk. Stroke prevention means use of
oral anticoagulation (OAC), whether with well managed
vitamin K antagonists (VKA), with time in therapeutic range >70%, or more commonly, label-adherent dosed
direct oral anticoagulant (DOAC).
high blood pressure,
chronic obstructive pulmonary disease,
stimulant use (e.g.,
methamphetamine dependence), and
excessive alcohol consumption.
Anticoagulants Anticoagulation medication can be used to reduce the risk of stroke from AF. Anticoagulation medication is recommended in most people with increased risk of stroke, which can be estimated using the
CHA2DS2-VASc score.
Direct oral anticoagulant (DOAC) are recommended over
warfarin in atrial fibrillation. In atrial fibrillation with presence of moderate to severe mitral stenosis or mechanical heart valve, warfarin is recommended over other therapies. although dabigatran is associated with a higher risk of
intestinal bleeding. Direct oral anticoagulant (DOAC), previously called "new", "novel", or "non-vitamin K antagonist" oral anticoagulant (NOAC), are medications taken orally that have another mechanism of action on the
coagulation cascade than
warfarin. DOACs recommended in atrial fibrillation include
apixaban,
dabigatran,
edoxaban and
rivaroxaban. The optimal approach to anticoagulation in people with AF and who simultaneously have other diseases (e.g.,
cirrhosis and
end-stage kidney disease on
dialysis) that predispose a person to both bleeding and clotting complications is unclear. For
vitamin K antagonists (VKA) such as
warfarin, time in therapeutic range (TTR) and
INR variability are commonly used to assess the quality of VKA treatment. Patients who are unable to maintain a therapeutic INR on VKA, as indicated by low TTR and/or high INR variability, are at an increased risk of thromboembolic and bleeding events. In these patients, treatment with a DOAC is recommended.
Rate versus rhythm control There are two ways to approach atrial fibrillation using medications: rate control and rhythm control. Both methods have similar outcomes.
Rate control lowers the heart rate closer to normal, usually 60 to 100 bpm, without trying to convert to a regular rhythm.
Rhythm control tries to restore a normal heart rhythm in a process called cardioversion and maintains the normal rhythm with medications. Studies suggest that rhythm control is more important in the acute setting AF, whereas rate control is more important in the long-term. The risk of stroke appears to be lower with rate control versus attempted rhythm control, at least in those with heart failure. AF is associated with a reduced quality of life, and, while some studies indicate that rhythm control leads to a higher quality of life, some did not find a difference. Neither rate nor rhythm control is superior in people with heart failure when they are compared in various clinical trials. However, rate control is recommended as the first-line treatment regimen for people with heart failure. On the other hand, rhythm control is only recommended when people experience persistent symptoms despite adequate rate control therapy. In those with a fast ventricular response, intravenous
magnesium significantly increases the chances of achieving successful rate and rhythm control in the urgent setting without major side-effects. A person with poor vital signs, mental status changes, preexcitation, or chest pain often will go to immediate treatment with synchronized direct current cardioversion. Rate control is achieved with medications that work by increasing the degree of the block at the level of the
AV node, decreasing the number of impulses that conduct into the ventricles. This can be done with: •
Beta blockers (preferably the "cardioselective" beta blockers such as
metoprolol,
bisoprolol, or
nebivolol) • Non-dihydropyridine
calcium channel blockers (e.g.,
diltiazem or
verapamil) •
Cardiac glycosides (e.g.,
digoxin) – have less use, apart from in older people who are sedentary. They are not as effective as either beta-blockers or calcium channel blockers. •
Chemical cardioversion is performed with medications, such as
amiodarone,
dronedarone,
procainamide (especially in
pre-excited atrial fibrillation),
dofetilide,
ibutilide,
propafenone, or
flecainide. After successful cardioversion, the heart may be stunned, which means that there is a normal rhythm, but the restoration of normal atrial contraction has not yet occurred.
Surgery Ablation Catheter ablation (CA) is a procedure performed by an
electrophysiologist, a
cardiologist who specializes in heart rhythm problems, to restore the heart's normal rhythm by destroying, or electrically isolating, specific parts of the atria. A group of cardiologists led by Dr
Haïssaguerre from noted in 1998 that the
pulmonary veins are an important source of ectopic beats, initiating frequent paroxysms of atrial fibrillation, with these foci responding to treatment with radio-frequency ablation. Most commonly, CA electrically isolates the left atrium from the
pulmonary veins, where most of the abnormal electrical activity promoting atrial fibrillation originates. Although radiofrequency ablation has become an accepted intervention in selected younger people and may be more effective than medication at improving symptoms and quality of life, there is no evidence that ablation reduces all-cause mortality, stroke, or heart failure. Some evidence indicates CA may be particularly helpful for people with AF who also have heart failure. AF may recur in people who have undergone CA and nearly half of people who undergo it will require a repeat procedure to achieve long-term control of their AF. As CA does not reduce the risk of stroke, many are advised to continue their anticoagulation. Use of pulsed field ablation as a non-thermal method of inducing
electroporation avoids damage to the phrenic nerve, esophagus, and blood vessels, while being at least as effective as thermal ablation methods. A hybrid convergent procedure has been developed which combines endocardial ablation with epicardial ablation, which can reduce AF recurrence to less than 5% for over one year. The epicardial ablation is performed first, with a minimally invasive surgical approach. In addition to procedures targeting the pulmonary veins, ablation can be utilized in an "ablate-and-pace" strategy for patients with coexisting refractory atrial fibrillation and heart failure. This procedure involves the ablation of the AV junction to block irregular electrical impulses from reaching the ventricles, combined with the implantation of a permanent
pacemaker (often involving
cardiac resynchronization therapy (CRT) via biventricular pacing or
conduction system pacing (CSP)) to maintain a stable heart rate. This approach is utilized when pharmacological rate control is ineffective or maintaining a durable sinus rhythm is unlikely, especially in individuals of advanced age or with significant comorbidities. The ablation itself may be performed either simultaneously with the device implantation or as a subsequent procedure.
Maze procedure An alternative to catheter ablation is surgical ablation. The
maze procedure, first performed in 1987, is an effective invasive surgical treatment that is designed to create electrical blocks or barriers in the atria of the heart. The idea is to force abnormal electrical signals to move along one, uniform path to the lower chambers of the heart (ventricles), thus restoring the normal heart rhythm. People with AF often undergo cardiac surgery for other underlying reasons and are frequently offered concomitant AF surgery to reduce the frequency of short- and long-term AF. Concomitant AF surgery is more likely to lead to the person being free from atrial fibrillation and off medications long-term after surgery and Cox-Maze IV procedure is the gold standard treatment. There is a slightly increased risk of needing a pacemaker following the procedure. Less invasive modifications of the maze procedure have been developed, designated as
minimaze procedures.
Left atrial appendage occlusion There is growing evidence that
left atrial appendage occlusion therapy may reduce the risk of stroke in people with non-valvular AF as much as warfarin. The addition of left atrial appendage isolation to catheter ablation has reduced AF recurrence by 80% in patients with persistent AF.
After surgery After catheter ablation, people are moved to a cardiac recovery unit,
intensive care unit, or cardiovascular intensive care unit where they are not allowed to move for 46 hours. Minimizing movement helps prevent bleeding from the site of the catheter insertion. The length of time people stay in the hospital varies from hours to days. This depends on the problem, the length of the operation, and whether or not general anesthetic was used. Additionally, people should not engage in strenuous physical activityto maintain a low heart rate and low blood pressurefor around six weeks. AF often occurs after cardiac surgery and is usually self-limiting. It is strongly associated with age, preoperative hypertension, and the number of vessels grafted. Measures should be taken to control hypertension preoperatively to reduce the risk of AF. Also, people with a higher risk of AF, e.g., people with pre-operative hypertension, more than three vessels grafted, or greater than 70 years of age, should be considered for prophylactic treatment. Postoperative pericardial effusion is also suspected to be the cause of atrial fibrillation. Prophylaxis may include prophylactic postoperative rate and rhythm management. Some authors perform posterior pericardiotomy to reduce the incidence of postoperative AF. When AF occurs, management should primarily be rate and rhythm control. However, cardioversion may be used if the patient is hemodynamically unstable, highly symptomatic, or AF persists for six weeks after discharge. In persistent cases, anticoagulation should be used. ==Prognosis==