Pharmacists diagnose stroke risk with iPhone-based ECG

Researchers at the University of Sydney have examined the use of a smartphone-compatible heart monitor to diagnose the risk of stroke.

The AliveCor heart monitor was approved by the FDA in late 2012 and hit the market for health care professionals in January 2013 — and now researchers at the University of Sydney have studied its use in a practical setting.

The monitor consists of either a smartphone case — for the purposes of this study, the iPhone version — or a universal attachment plate compatible with iOS and Android, which runs in wireless concert with an app. It is placed on the patient's chest and fingertips to administer an electrocardiogram (ECG) test.

According to the researchers, led by Nicole Lowres, if rolled out to the population of Australia aged over 65, the device could be used to prevent 1228 strokes over 10 years, or 122 strokes per year.

The study used the AliveCor monitor to test 1000 people aged over 65 for a condition known as atrial fibrillation, a common abnormal heart rhythm that causes a third of all strokes. It found atrial fibrillation in 1.5 per cent of the participants, or 15 people — but the most exciting part is that the test can be quickly, accurately and non-invasively administered in pharmacies.

"Unfortunately, many who have AF are unaware and have no symptoms that would lead them to visit their doctor," Lowres said. "We predicted this finding from our previous systematic review of all screening studies, which found a total incidence of unknown AF of 1.4 per cent in those over 65. We also found that AF screening picked up many people (about 5 per cent of all those screened) with known AF (known to their treating doctor). Unfortunately almost half of these did not know they had AF, even though most of them were taking powerful blood thinners. This indicates a great knowledge gap in people with this rhythm problem."

The AliveCor monitors, which cost US$199 each, would be well within a cost effective range, preventing disability and death due to stroke.

"The findings could change clinical practice guidelines on screening for atrial fibrillation, and could form part of health policy for governments or health service providers wishing to reduce the community burden of stroke. There will also be an increased recognition of the role health providers like pharmacists could play in screening for serious conditions using novel technology like the iPhone ECG," study senior author Professor Ben Freedman said.

"Screening in pharmacies and also in primary care by physicians and nurses to detect unknown AF in those over 65 might become part of routine practice, and could prevent death and disability from stroke. When screening becomes more generally available, those over 65 will want to include this as part of their regular health checks."

The full study, "Feasibility and cost effectiveness of stroke prevention through community screening for atrial fibrillation using iPhone ECG in pharmacies", will be available today in the journal Thrombosis and Haemostasis.