Today we’re launching the mRhythmStudy, which is a joint study within the Health eHeart effort at UCSF. The goal of this study is to understand how well heart rate data from the Apple Watch compares with data from medical grade devices, and to invite Apple Watch users to donate their heart rate data to help us build an algorithm for atrial fibrillation detection.
The cool thing is that you can help even if you’re completely healthy! Any data you contribute, whether you have atrial fibrillation or not, can help us improve the accuracy of our algorithm.
Atrial fibrillation (AF) is the most common arrhythmia and affects an estimated 2.7 million people in the US. AF increases the risk of stroke by five times over the general population, and strokes, in turn, is a leading cause of death in the US and worldwide. AF is often asymptomatic which means it is often undiagnosed until it is too late. 
If you have an Apple Watch, we invite you to join the mRhythmStudy and start donating your heart rate data today. You can help save a life!
We will be sharing details about how we’re applying deep learning for atrial fibrillation detection at Strata 2016 later this month. Come hear us speak if you’re interested!