The Kardia Band, a medical grade heart monitoring Apple Watch strap is now available to pre-order and is priced at £199.
US-based company AliveCor is responsible for bringing the smart strap to life and is headed up by ex-Google SVP of engineering Vic Gundotra.
While most Apple Watch owners will realise that the smartwatch already has the tech onboard to keep an eye on your ticker, question marks still remain over its ability to accurately detect heart rate activity.
Apple has even admitted that having a tattoo can interfere with the readings and that getting the precise right fit is vital for reliable bpm (beats per minute) readings from your Watch.
Essential reading: Best heart rate monitors and HRM watches
The Kardia Band is not a replacement fitness tracker however, but a medical grade heart rate monitor that has the potential to detect heart related issues like palpitations, shortness of breath and irregular heart rate which could increase the risk of a stroke.
How it all works
It all comes down to the type of technology AliveCor uses in its band. The current Apple Watch heart rate setup relies on something called photoplethysmography. This is essentially an optical heart rate sensor based technology that you similarly find on fitness wearables like the Fitbit Blaze or the Garmin Vivosmart HR+. It produces a reading by flashing lights against the skin to detect blood flow.
The Kardia Band uses electrocardiogram (EKG) technology, which detects the electrical activity produced by a heartbeat. It's still considered the most accurate way to record heart rate activity and is used by the medical industry and found inside heart rate monitor chest straps. So it's a big deal that AliveCor is able to bring the tech to the wrist.
All of the data is sent to the AliveCor companion app, which can be synced with Apple Health and should make it easier to share the information with your doctor to make use of the information.
You can pre-order the Kardia Apple Watch band, which will be available in 38mm and 42mm options from the AliveCor website now. It's expected to ship in early November.