Atrial fibrillation may be asymptomatic and therefore subclinical.
Utilizing screening electrocardiograms many patients receive a diagnosis of atrial fibrillation that had not been previously known.
May be asymptomatic and therefore subclinical.
Subclinical atrial fibrillation describes AF that is asymptomatic or that produces short-lasting, non-specific symptoms/findings that is not readily diagnosed by standard clinical testing, but is diagnosed only with the use of long-term continuous cardiac rhythm monitoring or an implanted, cardiac pacemaker or defibrillator.
Subclinical atrial fibrillation is reported to be present in more than 1/3 of all the patients with hypertension, who had received a pacemaker, and was associated with an increased risk of ischemic stroke with systemic embolism by a factor of 2.5.
Among patients with subclinical atrial fibrillation, anticoagulant therapy results in a lower risk of stroke, or systemic embolism than aspirin, but a higher risk of major bleeding (ARTESIA Investigators).
Approximately 25% of patients with ischemic strokes, no etiology is identified, and therefore subclinical atrial fibrillation is often suspected be the cause.
The prevalence of subclinical AF is unknown.
Screening for atrial fibrillation following an ischemic stroke identifies 4.4 cases of atrial fibrillation for every one hundred patients monitored.
Subclinical episodes of rapid atrial rate are detected in many patients with pacemakers and implantable cardioverter-defibrillators, and the detection of such episodes correlates well with electrocardiograph documentation of atrial fibrillation.
The rate of stroke is high in patients who have a pacemaker, with stroke occurring in 5.8% of patients within four years of implantation (Healey JS et al).