Differences between Atrial Fibrillation Detected before and after Stroke and TIA: A Systematic Review and Meta-Analysis

In a systemic review, published in Cerebrovascular Diseases, analysts compared characteristics of atrial fibrillation (AF) in patients whose AF was detected after a stroke (AFDAS) versus patients with AF known prior to a stroke (KAF).

 

Interestingly, the study “found significant differences in the prevalence of vascular comorbidities, structural heart disease, and stroke recurrence rates between AFDAS and KAF, suggesting that they constitute different clinical entities within the AF spectrum,” said lead author, Sebastian Fridman, from the Department of Clinical Neurological Sciences at the Schulich School of Medicine and Dentistry of Western University in London, Ontario, Canada.

 

Researchers applied random- or fixed-effects models to 21 studies, including 22,566 patients with ischemic stroke or transient ischemic attack, to compare differences in demographic factors, vascular risk factors, prevalent vascular comorbidities, structural heart disease, stroke severity, insular cortex involvement, stroke recurrence, and death between AFDAS and KAF.

 

In the AFDAS group, the incidence of coronary artery disease, congestive heart failure, prior myocardial infarction, and prior cerebrovascular events was significantly lower than in the KAF group. The risk of recurrent stroke was 26% lower in patients with AFDAS than in patients with KAF. Additionally, left atrial size was smaller and left ventricular ejection fraction was higher in AFDAS than KAF. There were no differences in age, sex, stroke severity, or death rates between AFDAS and KAF.

 

Authors noted that there were not enough studies to analyze different functions of the insular cortex between the two AF groups. However, they still felt that their results supported preliminary evidence that patients with AF detected after a stroke may have a less severe prognosis than AF detected in patients prior to a stroke.

 

The authors concluded, “We found significant differences in the prevalence of vascular comorbidities, structural heart disease, and stroke recurrence rates between AFDAS and KAF, suggesting that they constitute different clinical entities within the AF spectrum.”