Grond M, Jauss M, Hamann G, Stark E, Veltkamp R, Nabavi D, et al. Improved Detection of Silent Atrial Fibrillation Using 72-Hour Holter ECGin Patients With Ischemic Stroke: A Prospective Multicenter Cohort Study. Stroke. 2013
Roughly, 800,000 people in the United States suffer stroke every year. About 600,000 of these are first attacks, and 200,000 are recurrent attacks. More than 140,000 people die each year from stroke in the United States. Stroke death rate fell ~30% and the actual number of stroke deaths declined ~14% from 1995-2000, thanks to the outstanding efforts medical community on increased stroke awareness, primary and secondary stroke prevention. But can we do better?
I like this study, because it is simple and well executed.
1135 patients was enrolled in 9 German secondary and tertiary stroke centers between May 2010 and January 2011. All enrolled patients suffered stroke or TIA. 72 hour ECG monitoring was performed after patients with known A-Fib and patients with newly diagnosed A-Fib were excluded. Stroke mimics were excluded as well. Patients were monitored for the paroxysmal A-Fib 2 days longer than what standard of practice is. In 49/1135 patients (4.3%, 95%CI 3.4–5.2%) A-Fib was diagnosed, 29 patients (2.6%) within the first 24 hours of monitoring, and in 20 further (remaining 1.7%) patients during 25-72 hour monitoring. The number needed to screen by 72 hour ECG was 38 patients (95%CI 26-50) for each additional A-Fib diagnosis.
Patients with unknown A-Fib were significantly older and had more often a history of prior stroke. Interestingly, the affected vascular territories were not different, nor were multiple infarctions more common in either group.
Question remains: Is it beneficial to anticoagulate everybody with paroxysmal A-Fib. Should everybody be offered prolonged Holter monitoring? Should we select the population more likely to give us positive result; patients over 65 years? Is 3 days enough? Should we extend it to 7 days….or more? Can we switch to telemetry monitors instead of frequently present cardiac monitors (often unable to review) in the stroke units and incorporate prolonged EKG in all admitted stroke and TIA patients?
All of these questions need to be answered in subsequent trials, but this article just confirms my current practice. I am more and more inclined to offer prolonged EKG (7 days) to the patient over 65 and selected patients below 65. When A-Fib is confirmed and after calculating CHADS2 score (most of them start with at least 2 points for stroke or TIA), I offer them anticoagulation.