Wearables that measure blood pressure without bulky upper arm cuffs and attached electronics are on the way. The devices will be a boon to people with irregular heartbeats and to others for whom continuous monitoring is more useful than occasional one-time readings. We tried Valencell’s optic sensor with good results at CES 2017. Omron’s HeartGuide smartwatch, shown at CES 2018 and expected to launch later this year, has a self-inflating watchband for oscillometric blood pressure measurement.

Asus gave attendees an early look at the VivoWatch BP at Computex 2018 in Taiwan earlier this month. The new Asus smartwatch uses built-in ECG (electrocardiography) and PPG (photoplethysmography) sensors on the smartwatch’s front and back to monitor blood pressure throughout the day. By combining data from these two sensors, the device relies on pulse transit time (PTT) to infer blood pressure readings. Accurate results are captured in just 15 seconds, according to Asus. The VivoWatch BP also measures heart rate, tracks sleep quality, and counts daily steps. The Asus HealthAI algorithm uses data captured by the watch sensors to provide personalized health advice and blood pressure management tips. The watch updates an earlier version that lacked the biometric sensors, and now also has an integrated GPS and boasts 28-day battery life.

Asus is seeking FDA approval and expects to begin selling the VivoWatch BP in the U.S. in Q2 or Q3 2019. Sales in Asia start in July 2018. The race to deliver a wrist-worn device with accurate blood pressure readings is beginning to heat up, but until we see shipping commercial units of these products, it will be difficult to evaluate their value.