Atrial fibrillation (AFib) is the most common sustained heart rhythm disorder, affecting about 3 million American adults. The condition accounts for about 80,000 deaths each year in the United States, and its prevalence is projected to increase to 8 to 12 million over the next 30 to 40 years. “In addition to decreasing quality of life, AFib also dramatically increases the risk of stroke,” says Hugh Calkins, MD. The stroke rate among patients with AFib is increased about fivefold.
Studies show that the likelihood of developing AFib increases markedly with age. Afib is rare prior to the age of 50, but its prevalence increases dramatically thereafter. By the age of 80, one in 10 individuals has AFib. It is the most common heart rhythm abnormality in people older than 65, and about 70% of AFib patients are between the ages of 65 and 85. Other factors that increase the risk of developing AFib include male gender, hypertension, heart failure, family history, sleep apnea, and obesity.
Making an AFib Diagnosis
It can be challenging to diagnosis AFib because the signs and symptoms vary (Table 1). Some patients present with severe palpitations or presyncope, while others have no symptoms, with AFib first being detected on a routine physical examination. It is for this reason that the Heart Rhythm Society (HRS) encourages patients to check their pulse. If a patient detects a highly irregular pulse, a screening electrocardiogram (ECG) is advised. Continuous ECG monitoring systems are invaluable to detect AFib.
Guidelines recommend that patients who initially present with AFib be assessed using the CHA2DS2VASc risk criteria and examined for concomitant structural heart disease. “Establishing the level of risk for stroke will guide whether anticoagulation is recommended,” explains Dr. Calkins. “The more risk factors that patients have, the higher their stroke risk. It’s also important to identify potentially correctable causes of AFib.”
Individualizing Atrial Fibrillation Treatment
Options for AFib treatment include rate control medications, antiarrhythmic medications, catheter ablation, and surgical ablation (Table 2). When patients present with asymptomatic AFib, anticoagulation and rate control alone may be recommended.
“The decision for anticoagulation should be made based on each patient’s individual risk factors.”
It is important to recognize that symptoms of AFib may be subtle and include a sense of fatigue or decreased exercise tolerance. Older patients often attribute these to aging. “Many experienced clinicians try to restore sinus rhythm to reassess symptom status once sinus rhythm has been restored before abandoning a rhythm control strategy,” says Dr. Calkins. “However, rhythm control strategies do not obviate the need for anticoagulation. The decision for anticoagulation should be made based on each patient’s individual risk factors.”
When AFib patients are symptomatic after achieving adequate rate control, the goal should be to restore and maintain sinus rhythm. These patients should be referred to electrophysiologists or cardiologists for rhythm control with antiarrhythmic drugs and/or catheter or surgical ablation.
Acute & Long-Term Care of AFib Patients
For hemodynamically stable patients, anticoagulation and rate control are critical during acute care. For those who are hemodynamically unstable, patients may need immediate cardioversion and other medications. “During acute care, clinicians should consider admitting patients who are hemodynamically unstable or have significant comorbidities,” says Dr. Calkins. “They should also rule out secondary causes based on history, and perform reevaluations as necessary.”
Effective long-term treatment of AFib is critical, according to Dr. Calkins. “Antithrombotic therapy is recommended for all patients with AFib who are at increased risk of stroke based on their CHA2DS2VASc risk score, regardless of whether a rhythm or rate control strategy is chosen. Long-term treatment should aim to improve symptoms, functional capacity, and quality of life. Most AFib patients will require anticoagulation. Fortunately, the three new anticoagulants—dabigatran, rivaroxaban, and apixaban—have been shown to be safe, effective, and convenient in clinical trials.”
Dr. Calkins notes that it is important to recognize that aspirin is not an effective anticoagulant. “Use of aspirin increases bleeding risk to a similar degree as anticoagulants while doing little to reduce stroke risk.”
Atrial Fibrillation Awareness Month
September is Atrial Fibrillation Awareness Month, an initiative led by the HRS to increase knowledge of AFib, including its symptoms, warning signs, and available treatment options. Dr. Calkins says physicians should get involved in the effort by being proactive with patients. “AFib is a potentially deadly condition that is expected to become more prevalent as society continues to age. Fortunately, we have safe and effective treatments available that—when initiated early and appropriately—can help prevent future strokes and cardiac events. Efforts by the HRS and other groups to educate healthcare providers and the public about the AFib will help decrease the disease burden in the future.”
To learn more about Atrial Fibrillation Awareness Month, go to http://www.hrsonline.org. The Heart Rhythm Society also offers guides several helpful pocket guides for clinicians managing patients with atrial fibrillation. Two of these guides—“Managing the Patient With Atrial Fibrillation” and “Practical Rate and Rhythm Management of Atrial Fibrillation”—are available as free downloads.
Heart Rhythm Society. Managing the Patient With Atrial Fibrillation Pocket Guide. Available at: http://www.hrsonline.org/content/download/2153/29275/file/2013-Rate-Rhythm-Pocket-Guide.
Heart Rhythm Society. Practical Rate and Rhythm Management of Atrial Fibrillation Pocket Guide. Available at: http://www.hrsonline.org/content/download/2154/29279/file/Managing%20the%20Patient%20with%20Atrial%20Fibrillation%20Pocket%20Guide.
Heart Rhythm Society. Atrial Fibrillation Fact Sheet. Available at: http://www.hrsonline.org/News/Fact-Sheets/AFib-Facts#axzz2bxdjPpBT.
Fuster V, et al. 2011 ACCF/AHA/HRS focused updates incorporated into the ACC/AHA/ESC 2006 Guidelines for the management of patients with atrial fibrillation.
J Am Coll Cardiol. 2011; 57: e101-98.
Wann SL, et al. 2011 ACCF/AHA/HRS Focused update on the management of patients with atrial fibrillation (updating the 2006 guideline). Circulation. 2011;123:104-123.
Lip GY, et al. Identifying patients at high risk for stroke despite anticoagulation: a comparison of contemporary stroke risk stratification schemes in an anticoagulated atrial fibrillation cohort. Stroke. 2010;41(12):2731-8.
Calkins, H, et al. 2012 HRS/EHRA/ECAS Expert consensus statement on catheter and surgical ablation of atrial fibrillation. Heart Rhythm. 2012; 9:632-696.
Camm AJ, et al. Guidelines for the management of atrial fibrillation. The Task Force for the Management of Atrial Fibrillation of the European Society of Cardiology (ESC). Eur Heart J. 2010; 31(19):2369–2429.
Lip GY, et al. Improving stroke risk stratification in atrial fibrillation. Am J Med. 2010;123(6):484-8.