OPPO has announced what it is calling a smartwatch with "professional"-grade electrocardiography (ECG) features. This is because it has been officially certified as such a device, albeit in China only. This wearable, which looks like the OEM's inaugural Watch, will launch worldwide in September 2020.
https://www.notebookcheck.net/An-ECG-Edition-of-the-OPPO-Watch-will-launch-soon.494792.0.html