Today the US Patent & Trademark Office published two major continuation patent applications from Apple relating to one day having Apple Watch provide users with a viable blood pressure feature.
Raised blood pressure throughout its range is the most significant cause of death and disability in the world (Lopez et al. 2006). Accurate blood pressure measurement is therefore vital in the prevention and treatment of blood-pressure–related diseases.
Being able to provide consumers with this feature on a future Apple Watch would be a major breakthrough adding to its other important health features such as measuring blood oxygen levels and ECG.
Apple Watch measuring Blood Pressure
Apple's patent FIG. 10 above is from continuation patent number 20200367760. The figure represents a schematic side view of a wrist-worn blood pressure measurement device held in contact with a user's chest.
Three years ago, Patently Apple posted an IP report titled "Apple is Developing Watch Technology to Detect Heart Abnormalities and now blood Pressure." The patent application from Apple was titled "Wrist Worn Accelerometer for Pulse Transmit Time (PTT) Measurements of Blood Pressure" that related to the Apple Watch one day being able to measure blood pressure in a very sophisticated manner.
Apple published a series of such patents dating back to 2014 and today two of them have resurfaced as continuation patents published by the U.S. Patent Office.
If you happen to be in the medical field or just a curious Apple fan that wishes to follow Apple's latest updates regarding blood pressure advancements for Apple Watch, today's dual continuation patents are major updates that may interest you.
Both continuation patents are linked to below so that you could review the new patent claims when you have the time and at your own pace. Each of the patents linked to below are provided with the first patent claim of each as the first claim of patents usually sets the course for the underlying claims.
Continuation Patent 20200367767 titled "Electrical Coupling of Pulse Transit Time (PTT) Measurement System to Heart for Blood Pressure Measurement." The previous patent covered 29 patent claims all focused on "A wrist-worn Device." Today's continuation patent adds 20 new claims all focused on "The method" of determining one or more blood pressure values of a subject.
The first Patent Claim states the following:
"A method of determining one or more blood pressure values of a subject, the method comprising: propagating an alternating drive current through the subject between a first drive current electrode and a second drive current electrode, wherein the second drive current electrode is externally located on a wrist-worn device worn on a wrist of the subject and engaged with the subject so that a portion of the alternating drive current travels through the thorax of the subject, and wherein the first drive current electrode is non-invasively engaged with the subject's skin at the wrist; sensing voltage levels of the subject resulting from the alternating drive current via a first sense electrode and a second sense electrode, wherein the second sense electrode is externally located on the wrist-worn device and engaged with the subject so as to sense a voltage level induced by the alternating drive current, and wherein the first sense electrode is non-invasively engaged with the subject's skin at the wrist; processing the voltage levels to detect when a volume of blood is ejected from the left ventricle; processing output from a pulse arrival sensor coupled to the wrist-worn device to detect when a blood pressure pulse generated by ejection of the volume of blood from the left ventricle arrives at the wrist; calculating a pulse transit time (PTT) for transit of the blood pressure pulse from the left ventricle to the wrist; and determining one or more blood pressure values for the subject based on the PTT."
Continuation patent 20200367760 titled "Blood Pressure Monitoring Using a Multi-Function Wrist-Worn Device." This patent is a little more complex in that the last granted patent only carried 7 patent claims, even though the previous patent application had 56 with the patent noting that claims #56-68 were cancelled.
The first Patent Claim (which is now claim #69) states the following:
"A method for obtaining a blood pressure measurement of a subject, the subject having a cardiovascular system including a left ventricle and a wrist covered by skin, the method comprising: sensing, with a pulse ejection sensor of a wrist-worn device non-invasively engaging the skin on the wrist of the subject, a first ejection signal indicative of when a first volume of blood is ejected from the left ventricle; sensing, with a pulse arrival sensor of the wrist-worn device non-invasively engaging the skin on the wrist of the subject, a first pulse arrival signal indicative of when a first pressure pulse generated by an ejection of the first volume of blood from the left ventricle arrives at the wrist; determining, based on the first ejection signal and the first pulse arrival signal, a first pulse transit time (PTT) for transit of the first pressure pulse from the left ventricle to the wrist; determining a first relative blood pressure value based on the first PTT; receiving a first measured reference absolute blood pressure value associated with the first relative blood pressure value; and determining a first absolute blood pressure value for the first relative blood pressure value based on the first measured reference absolute blood pressure value and the first relative blood pressure value."
Today's continuation patent 20200367760 cancelled all previous patent claims #1-68 and replaced them with 25 new patent claims numbered 69- 94. All of the claims are focused on "The Method" of determining one or more blood pressure values of a subject.
Considering that these are continuation patents, the timing of bringing a blood pressure measurement feature to the Apple Watch is unknown at this time.
You could review our 2017 patent application for more details for the general idea of the invention. The report also provides you with several more patent figures to review.