Apple patents Watch blood pressure monitoring tech


While its new line of smartphones dominates the headlines, Apple is continuing to push on with its healthcare ambitions, filing for a patent that would allow the Apple Watch to monitor blood pressure.

The patent, entitled “Wrist Worn Accelerometer for Pulse Transmit Time (PTT) Measurements of Blood Pressure”, describes technology that combines data gathered by two different sensors in the Watch.

The first data source is the Watch’s built-in heart rate sensor which can indicate a user’s pulse. The second data source is an accelerometer which, when placed against the heart, can detect the moment blood exits the left ventricle.

By timing the difference between the blood exiting the heart and reaching the wrist (the pulse transit time), blood pressure can be determined.

[caption id="attachment_32731" align="alignnone" width="699"] The patent describes an Apple Watch which, when pressed against the chest, can determine blood pressure. [/caption]

“Elevated blood pressure (aka hypertension) is a major risk factor for cardiovascular disease,” states the patent. “Timely detection of hypertension can help inhibit related cardiovascular damage via accomplishment of effective efforts in treating and/or controlling the subject’s hypertension.”

Current ambulatory and home blood pressure measurement approaches fail to provide continuous measurement of blood pressure, says the patent, whilst continuous measurement using a cuff can be disruptive to sleep patterns.

The news of the patent comes after last week’s listing of Apple as one of nine companies selected for the FDA’s Pre-Cert Program pilot.

Designed to streamline the approval of innovative solutions, the Program asks for less pre-market data for new tools from trusted ‘pre-certified’ companies, instead basing approval on post-market real-world evidence.

Interestingly, Apple CEO Tim Cook stated that the company did not want to include too many health-related sensors in the Watch back in 2015 due to complex regulatory approval systems. The time it would take for each new sensor to be approved would hinder the overall evolution of the Watch, said Cook.

But the company could see the new pilot programme as a way of both continuing to push its Watch into more health-focused territory whilst maintaining a decent technological evolutionary pace.

Marco Ricci

13 October, 2017