Prof Graeme Hankey
Older age, higher body mass index, hypertension and the absence of diabetes can help identify people at higher risk of developing atrial fibrillation (AF) after an embolic stroke of undetermined source (ESUS), a new study shows.
An analysis of the international RE-SPECT ESUS study of dabigatran versus aspirin, originally published in 2015, found 7.5% of ESUS patients developed AF during the following 19 months.
The study, published in Circulation, found significant independent predictors of AF were older age (OR for 10-year increase 1.99 (1.78–2.23); P<0.001), hypertension (OR, 1.29 [1.16–1.43); P=0.0304), diabetes (OR, 0.74 [0.56–0.96]; P=0.0226), and BMI for 5-U increase (OR, 1.29 [1.16–1.43]; P<0.001).
“Using this model, the probability of developing AF was 5 times greater in the third quartile than the first quartile (HR, 5.34 [95% CI, 3.88–7.34]; P<0.001),” the study authors said.
In a subgroup of patients who had baseline NT-proBNP levels, only older age (OR per 10 years, 1.34 [1.08–1.66]; P=0.0067) and elevated NT-pro BNP (OR per 1-U increase on log scale, 1.74 [1.40–2.16]; P<0.001) were independent predictors of AF.
The study found the annualised rate of recurrent stroke in patients with ESUS who developed AF was higher than in patients without AF (7.0% versus 4.2%; HR, 1.75 [95% CI, 1.30–2.35]; P=0.0002).
“Therefore, early detection and treatment of AF should be a priority in patients who have had ESUS,” the study authors said.
Better understanding of the risk for development of AF is critical to implement optimal monitoring strategies with the goal of preventing recurrent stroke attributable to underlying AF, they added.
“With 2 large randomised trials having shown no benefit for anticoagulation over aspirin in patients with ESUS, it has been suggested that the main opportunity is to intensify diagnostic workup of ESUS, including identification of those who have AF” they said.
“In this sense, our study shows that simple clinical variables and, when available, levels of NT-proBNP could help identify a population of patients who may benefit from prolonged cardiac monitoring.”
An editorial by Professor Graeme Hankey, a Consultant Neurologist at the Sir Charles Gairdner Hospital, Perth, said the study showed simple clinical variables could help identify “an important minority of ESUS patients who will soon develop AF (or already have covert AF or an arrhythmogenic or thrombogenic atrial cardiopathy).”
He noted the American Heart Association/ American Stroke Association guidelines recommend long-term rhythm monitoring with mobile cardiac outpatient telemetry, an implantable loop recorder, or other approach is reasonable to detect intermittent AF in people with ESUS.
He also said treatment with direct oral anticoagulants or with ticagrelor was not recommended over aspirin to reduce the risk of secondary stroke.