Lone atrial fibrillation: Summary of current knowledge

GDANSK, POLAND. A team of British and Polish researchers has summarized the current knowledge about lone atrial fibrillation. Among the highlights of their findings are:

  • About 4.5 million people in the European Union suffer from atrial fibrillation (AF).
  • Lone atrial fibrillation (LAF) constitutes between 1.6 and 11.4% of all cases of AF.
  • The estimated risk of progression from paroxysmal LAF to permanent LAF is about 29% over 30 years.
  • LAF in patients with normal left atrial volume at initial diagnosis has a benign clinical course over long-term follow-up.
  • Men comprise about 78% of the LAF population.
  • Lone afibbers are more likely to have a first-degree family member with afib than are those with AF.
  • Lone afibbers are statistically taller and leaner than other patients with AF. NOTE: This conclusion is based on PC’s article “Lone Atrial Fibrillation: Pathologic or Not?” which in turn is based on our LAF Survey 11.
  • Lone afibbers whose episodes are caused by acute stress revert to normal sinus rhythm quicker than do afibbers whose episodes are caused by other triggers.
  • Participation in endurance sports has been linked to an increased incidence of LAF.
  • Sleep apnea syndrome is associated with an increased incidence of LAF.
  • LAF can be initiated by several common drugs.
  • The level of brain natriuretic peptides (BNPs) is significantly increased among lone afibbers, but decline markedly after a successful electrical cardioversion.
  • There is an association between inflammation and LAF, but it is not clear whether inflammation causes afib or afib causes inflammation.
  • In patients with LAF the risk of thromboembolism (stroke and transient ischemic attacks) is low without treatment and anticoagulation with warfarin is not recommended unless patients have specific risk factors for stroke.
  • There is no evidence that aspirin therapy is beneficial for lone afibbers. A recent Japanese trial concluded that the administration of 150 – 200 mg of aspirin daily for stroke prevention is neither effective nor safe in lone afibbers.
  • There is some indication that statin drugs may help prevent recurrence of afib following a successful cardioversion.

The research team in the last table of their report makes quite clear that there is a very distinct difference between the pathological form of AF (about 90% of cases) and LAF. The main comorbid conditions associated with AF are heart failure, hypertension, valve abnormalities, cardiomyopathies, cardiac ischemia, diabetes, and thyroid disease. In contrast, the main factors associated with LAF are male gender, familial predisposition, genetic factors, stress, alcohol consumption (binge drinking), participation in endurance sports, sleep apnea, systemic inflammation and possibly, concealed cardiac dysfunction.

Kozlowski, D, et al. Lone atrial fibrillation – What do we know? Heart, August 26, 2009 [Epub ahead of print]

Editor’s comment: Although the findings reported in this study are generally not new to readers of The AFIB Report, it is valuable to have them all condensed into one review. It is unfortunate though that the authors completely ignore the importance of electrolyte imbalances as a major cause of LAF. A recent study found that close to 90% of all lone afibbers are deficient in magnesium and many afibbers have found that supplementation with magnesium, potassium and taurine is very helpful in preventing ectopics and episodes.