Could AliveCor SmartRhythm Monitoring Revolutionise AF Detection?

The latest App version 5.0.2 from AliveCor introduces a new premium feature “SmartRhythm” monitoring.

What is SmartRhythm monitoring?

SmartRhythm monitoring from AliveCor is a system that takes heart rate and activity data gathered from an Apple Watch, and evaluates it using a deep neural network to predict heart rate patterns. If  heart rate differs from the neural network prediction, SmartRhythm will notify you to record an ECG either on your phone with Kardia Mobile or for convenience and if you have one with the KardiaBand.

Taking frequent ECGs can help you better manage your heart health, and capturing an ECG specifically during times when heart rate does not match activity levels may be useful.

SmartRhythm monitoring uses the Apple Watch Photoplethysmogram (PPG) sensor to evaluate heart rate approximately every 5 seconds. Your heart rate itself depends on many factors such as activity, stress, time of day and more. So at times your heart rate pattern should be high (during exercise), sometimes, it should be low (at rest) and sometimes it may signify a heart problem.

Patented AliveCor SmartRhythm monitoring technology uses an autoregressive, deep neural network that can learn the normal relationship between heart rate and activity, and notify you when it sees an unexpected pattern. It notifies you when the actual data from the Apple Watch doesn’t match what the SmartRhythm model expects to see.

Receiving a SmartRhythm notification does not necessarily mean that something is wrong. There are many perfectly normal situations that can cause a SmartRhythm notification, including exercise the Apple Watch can’t detect, stress or anxiety, consumption of caffeine or alcohol, and even motion artifact from wearing the watch band too loosely.

Conversely, not getting a SmartRhythm notification does not necessarily mean that everything is normal, since the Apple Watch sensor is only measuring your heart rate and does not capture the full complexity of your heart. SmartRhythm monitoring should be used as an additional means to capture frequent ECGs.

Does SmartRhythm monitoring affect Apple Watch battery life?

Yes. SmartRhythm causes a higher battery usage and you will need to charge your Apple Watch more frequently. This is because SmartRhythm requires the Apple Watch to be in Workout mode as it is evaluating heart rate data continually which increases battery usage.

AliveCor internal testing has shown that with a series 2 or newer watch you can expect around 16 hours of battery life. It can still be worn over night just top up the charge for an hour or so.

The first generation Apple Watch is not supported because it has a smaller battery and will only last 5 hours.

What’s Next?

Kardia for Apple Watch is just the first step in bridging the gap between consumer wearable devices and the science of clinically validated ECG healthcare devices.

The availability of a wearable, mobile ECG device like the Kardia has the potential to dramatically improve early detection of arrhythmias. Many arrhythmias start as occasional, intermittent problems that usually don’t show up in a doctor’s office and are notoriously difficult to diagnose.

AliveCor products including the Kardia Mobile and Kardia Band are available directly from UK Distributor PMS Instruments.

AliveCor®, KardiaBand™ and SmartRhythm™ are trademarks of AliveCor, Inc. Apple Watch® is a trademark of Apple Inc.