About Atrial Fibrillation

AFib: the most commonly encountered
sustained cardiac arrhythmia.

About Atrial Fibrillation (AF)

Atrial fibrillation (AF) is the most commonly encountered sustained cardiac arrhythmia (abnormal heart rhythm), and involves the two upper chambers (atria) of the heart. Its name comes from the abnormal fibrillating (i.e. quivering) of the heart muscles of the atria instead of the normal coordinated contraction.

AF prevalence increases with age with an estimated 9% prevalence in patients ages >65. It is estimated that up to 6 million people in the United States have AF; This number is expected to double by 20501-3.

AF is associated with a significant morbidity and a substantial reduction of quality of life in some patients. The consequences of atrial fibrillation range from none to debilitating, including:

  • Exercise intolerance
  • Congestive heart failure
  • Tachycardia-induced cardiomyopathy (fast heart rate causing heart muscle damage)
  • Stroke4 (clots in the brain)

AF is thought to be responsible for 15% of the strokes occurring in elderly patients1. Furthermore, AF is associated with a 50% to 100% increased risk of death4. Besides age, known risk factors for AF include hypertension, left ventricular hypertrophy (increased heart muscle thickness), diabetes, and cigarette smoking5.

AF is a chronic, progressive condition
which is traditionally classified into three category types.6

About Paroxysmal Atrial Fibrillation (PAF)

Paroxysmal atrial fibrillation (PAF) is a type of AF where episodes terminate spontaneously in less than 7 days. About 1 in 4 people with paroxysmal atrial fibrillation eventually develop the permanent form of the condition within 5 years7. Common symptoms of PAF can include:

  • Racing heartbeat
  • Fluttering feeling in the chest
  • Chest pain or pressure
  • Feeling out of breath
  • Weakness or tiredness
  • Dizziness and sweating
  • Faintness or lightheadedness4

The underlying causes of PAF aren’t always known. They can be similar to causes of chronic AF, although most people with PAF have normal heart structure. People with PAF appear to be at just as high a risk of developing blood clots in the atria as those with chronic AF.

PAF Episodes May Last Up To 7 Days

  • The Management of PAF has Three Key Objectives

    • 1) Prevention of stroke
    • 2) Symptom relief achieved with either rhythm control (restoration of normal sinus rhythm) or with rate control (slowing of heart rate) therapies.
    • 3) Prevention of progression to chronic atrial fibrillation with its associated complications such as heart failure8

    Selection of a primary therapeutic strategy of rhythm control or rate control is a multifactorial decision depending on the patient’s age, symptoms, importance of and desire to maintain sinus rhythm. Current therapies for rhythm control include:

    • Antiarrhythmic Drugs (AADs) – Medications taken orally or IV that normalize the heart rhythm by its actions on ion channels in heart muscle cells.
    • Electrical Cardioversion – A medical procedure, usually done in hospitals under general anesthesia, that normalizes heart rhythm by delivery of a quick, large electric current across electrodes attached to the skin.
    • Catheter Ablation – A surgical procedure performed by specialized cardiologists (clinical electrophysiologists) which involves burning or freezing heart muscle tissue in patterns that isolate sources of arrhythmia.

    The efficacy, safety, tolerability and contraindications of the current therapeutic options have been extensively described in numerous reviews and in the relevant medical guidelines 6-8.

1. Go AS, Hylek EM, Phillips KA, Chang Y, Henault LE, Selby JV, et al. Prevalence of diagnosed atrial fibrillation in adults: national implications for rhythm management and stroke prevention: the AnTicoagulation and Risk Factors in Atrial Fibrillation (ATRIA) Study. JAMA 2001;285(18):2370-5.
2. January CT, Wann LS, Alpert JS, Calkins H, Cigarroa JE, Cleveland JC, Jr., et al. 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on practice guidelines and the Heart Rhythm Society. Circulation 2014;130(23):2071-104.
3. Chugh SS, Roth GA, Gillum RF, Mensah GA, Glob Heart. 2014 Mar;9(1):113-9
4. American Heart Association website “What are the Symptoms of Atrial Fibrillation (AFib or AF)?” www.heart .org (accessed July 2018).
5. Kannel WB, Wolf PA, Benjamin EJ, Levy D. Prevalence, incidence, prognosis, and predisposing conditions for atrial fibrillation: population-based estimates. Am J Cardiol 1998;82(8A):2N-9N.
6. Kirchhof P, Benussi S, Kotecha D, Ahlsson A, Atar D, Casadei B, et al. 2016 ESC Guidelines for the management of atrial fibrillation developed in collaboration with EACTS. Eur Heart J 2016;37(38):2893-2962.
7. Kerr CR, Humphries KH, Talajic M, Klein GJ, Connolly SJ, Green M, Boone J, Sheldon R, Dorian P, Newman D; Am Heart J. 2005 Mar;149(3):489-96
8. Cosio FG1, Aliot E, Botto GL, Heidbüchel H, Geller CJ, Kirchhof P, De Haro JC, Frank R, Villacastin JP, Vijgen J, Crijns H, Europace. 2008 Jan;10(1):21-7. Epub 2007 Dec 17