Cardiogram allows you to join an ambitious study to detect the most common heart arrhythmia using your smart watch. Contribute your data and save lives.

Each year, more than 100,000 strokes are caused by an abnormal heart rhythm called atrial fibrillation. In atrial fibrillation, electrical conduction in the heart becomes disorganized. The upper chambers may beat 300-600 times per minute. The lower chambers may beat at a normal rate, but irregularly. Atrial fibrillation is treatable, but many people don't feel symptoms, so it often goes undiagnosed.

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