AF duration linked to outcomes after stroke thrombolysis
MedWire News: Patients with atrial fibrillation (AF) are at high risk for poor outcomes after receipt of recombinant tissue plasminogen activator (rtPA) for acute stroke, particularly if they have had the arrhythmia for a long time, research suggests.
"This information is useful to identify stroke patients at higher risk for adverse stroke outcomes following rtPA treatment who may benefit from closer blood pressure control and monitoring and, perhaps, early endovascular treatment," say Raymond Seet (Mayo Clinic, Rochester, Minnesota, USA) and team.
Patients with a first-ever AF episode did not appear to be at increased risk for poor outcomes, although the researchers note that they could not distinguish between patients with a genuine first episode and those who may have had undiagnosed paroxysmal AF.
The team's study, which appears in the Archives of Neurology, included 214 stroke patients who received intravenous thrombolysis but did not undergo an endovascular procedure. AF was present in 76 patients, of whom 44 had paroxysmal AF and 32 had persistent AF.
Patients with AF were more likely to have a symptomatic intracranial hemorrhage (ICH) than those without, at 16% versus 5%, and this remained significant after accounting for age and stroke severity, with AF conferring a 2.95-fold increased risk for ICH.
AF patients who developed symptomatic ICH had a longer history of AF than those who did not, at 59 versus 23 months.
Poor functional outcomes, defined as a modified Rankin Scale score higher than 2, were also more common among patients with AF than those without, at 62% versus 44%, and duration of AF was longer in AF patients with than in those without poor functional outcomes, at 36 versus 16 months. However, the association between AF and functional outcome disappeared after adjustment for age and stroke severity.
"These data also highlight a high frequency of paroxysmal AF among stroke patients who present within the time window for rtPA treatment," say Seet et al, noting that about 60% of the AF patients in their study had paroxysmal AF.
They say: "Despite carrying the same stroke risk as permanent or persistent AF, the burden of paroxysmal AF among rtPA-treated patients is underrecognized."
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By Eleanor McDermid