Typical atrial flutter (AFL), a condition which affects an estimated 200,000 new patients annually, has been defined as a pattern of regular tachycardia originating in the right atrium with an atrial rate of 240 beats/minute or higher. The current prevalence of AFL is high and is projected to increase considerably by 2050. Although not as common as atrial fibrillation, AFL can be a chronic condition. If left untreated, AFL can lead to debilitating symptoms, including shortness of breath, palpitations, dizziness, fainting, chest tightness, fatigue, and weakness. It can significantly impair quality of life and is associated with impaired cardiac output, atrial thrombus formation, and stroke. With proper treatment, however, AFL is rarely life threatening and symptoms can usually be managed effectively.
“Atrial flutter is a common condition which should be treated appropriately to alleviate symptoms and prevent clot formation,” says Angelo Biviano, MD, MPH. Dr. Biviano adds that AFL in some patients can be associated with atrial fibrillation, and proper diagnosis and treatment is imperative. Research suggests that elimination of AFL may delay but not prevent fibrillation. Therefore, proper diagnosis and treatment of AFL is imperative. “The good news is that several treatment strategies exist for AFL,” says Dr. Biviano. “Consideration of patients’ medical history as well as their preferences will help guide treatment strategies for patients.”
AFL may be caused by abnormalities or diseases of the heart as well as diseases elsewhere in the body that affect the heart. These include diseases of the heart valves, especially the mitral valve, and chamber enlargement/hypertrophy. Diseases of the heart that have been linked to AFL include ischemia, atherosclerosis, myocardial infarction, hypertension, and cardiomyopathy. Other diseases/conditions associated with AFL include hyperthyroidism, pulmonary embolism, COPD and emphysema, alcoholism, and stimulant abuse. Some patients with AFL will experience few or no symptoms. For this reason, AFL is often identified incidentally with an electrocardiogram. Other ways to diagnose AFL include cardiac rhythm assessment with outpatient Holter monitoring, event monitors, or more prolonged continuous rhythm monitors.
Once a diagnosis of AFL is made, treatments to be considered include using a rate control strategy or a rhythm control strategy. In rate control strategies, patients with AFL are left in AFL but the ventricular response to the atrial rhythm is controlled with β-blockers or calcium channel blockers. With rhythm control strategies, patients are given more powerful antiarrhythmic medications and/or may receive percutaneous catheter ablation in an attempt to keep them in normal sinus rhythm. Regardless of strategy, candidacy for anticoagulation with the goal of reducing embolism/stroke risk needs to be addressed.
“The good news is that several treatment strategies exist for AFL. Consideration of patients’ medical history as well as their preferences will help guide treatment strategies for patients.”
Pharmacologic therapy has long been considered a standard initial therapeutic approach for AFL, but patients may experience side effects from antiarrhythmic therapies. In these cases, cardioversion (either electrical or pharmacologic) and/or percutaneous catheter ablation may be preferred (Table 1). Cardioversion usually converts patients to sinus rhythm quickly and effectively, but recurrences are more common when compared to catheter ablation, which has a high success rate, relatively low complication rate, and lower recurrence rate of patients.
Patient preference and the presence of comorbidities should be taken into consideration when selecting treatment options. “There are several levels of intervention that can be utilized to treat AFL,” Dr. Biviano explains. “The treatment that is chosen should be tailored to the needs of patients, keeping in mind that many may require more than one type of treatment [Table 2].”
Due to the increasing prevalence of AFL, there has been an increased need to develop better therapeutic approaches for the arrhythmia. Researchers and drug developers are continuing efforts to design novel pharmacologic options that aim to terminate AFL and prevent recurrence. As research sheds more light on newer therapeutics, there is hope that clinicians will have more effective and convenient options to offer patients. In concert with the research and development of pharmacologic therapies, there is also an ongoing evolution of ablation and device approaches. Catheter-based cryoablation as well as different sizes and energy-delivery options for radiofrequency ablation has been shown to be a new effective treatment option for AFL in select patients. “With emerging new therapies and treatment options,” Dr. Biviano says, “clinicians may be able to improve outcomes and reduce the burden of AFL in the future.”
In concert with the research and development of pharmacologic therapies, there is also an ongoing evolution of ablation and device approaches. Catheter-based cryoablation as well as different sizes and energy-delivery options for radiofrequency ablation has been shown to be a new effective treatment option for AFL in select patients. “With emerging new therapies and treatment options,” Dr. Biviano says, “clinicians may be able to improve outcomes and reduce the burden of AFL in the future.”
Readings & Resources (click to view)
Dhar S, Lidhoo P, Koul D, Dhar S, Bakhshi M, Deger FT. Current concepts and management strategies in atrial flutter. South Med J. 2009;102:917-922. Available at: http://www.sma.org/pdfs/objecttypes/smj/C85DEA42-1109-A387-6097C461E1FED5FD/917.pdf. Accessed October 22, 2009.
Manusama R, Timmermans C, Pison L, et al. Typical atrial flutter can effectively be treated using single one-minute cryoapplications: results from a repeat electrophysiological study. J Interv Card Electrophysiol. 2009;26:65-72. Epub 2009 Jun 12.
Naccarelli GV, Varker H, Lin J, Schulman KL. Increasing prevalence of atrial fibrillation and flutter in the United States. Am J Cardiol. 2009;104:1534-9.
Sawhney NS, Feld GK. Diagnosis and management of typical atrial flutter. Med Clin North Am. 2008;92:65-85.
Singh BN, Connolly SJ, Crijns HJGM, et al. Dronedarone for maintenance of sinus rhythm in atrial fibrillation or flutter. N Engl J Med. 2007;357:987-999.