(NC) -- Atrial fibrillation (AF) means you have an irregular heartbeat or arrhythmia. Silent or intermittent arrhythmias are a major cause of stroke in Canada. In these cases you may feel perfectly fine, or you may only experience mild, non-specific symptoms such as lightheadedness, fluttering heartbeat and nausea – that only lasts a few minutes.

“Doctors used to think that patients with intermittent symptoms weren't worrisome, but that's starting to change,” says Dr. Jeff Healey, an associate professor of cardiology at McMaster University in Hamilton. “We're seeing that most patients with atrial fibrillation— whether they feel symptoms or not— are predisposed to stroke.”

Dr. Healey, recipient of a 2013 Heart and Stroke Foundation Mid-Career Investigator Award, is investigating better ways to detect and treat the silent – but still deadly – arrhythmias that lurk below the surface.

“If we rely solely on symptoms, we're going to miss a lot,” he says. “The good news is that there is a wealth of new, inexpensive, easy-to-use technologies that can record the heart's electrical activity and help detect if an irregular heartbeat is present.”

About 350,000 Canadians live with AF – many of them unaware of the condition. Dr. Healey hopes to use existing technologies to detect and treat these silent cases to further reduce the number of strokes.

Find out more about AF at www.heartandstroke.ca/bepulseaware. While on the site, take a look at a few of the helpful short videos and share them with interested friends and family.