Developed over seven years by our dedicated medical research team, U.S. Patent No. 11,219,373 for the Cardiac Arrest Technologies CA Rescue™ Watch discloses a cardiac arrest wearable device that automatically detects a suspected event and alerts the nearest emergency medical services. This reduces the likelihood of death or severe morbidity associated with out-of-hospital sudden cardiac arrest events.
The cardiac arrest patent combines a photoplethysmography-based sensor with a miniature laser Doppler-based sensor in a wristwatch to monitor both heart rate and blood flow velocity within arterial vessels of the wrist.
Figure 1
During the development of our cardiac arrest watch, tests were performed on human subjects. Using a miniature 1.6 mm wide x 3.2 mm long x 0.9 mm thick laser Doppler transducer developed and manufactured by Kyocera Corporation (Figure 1), our goal was to measure the cardiac arrest detection ability of the watch.
In these tests, a cardiac arrest was simulated by inflating a pneumatic blood pressure cuff tourniquet applied to the upper arm while using the laser Doppler transducer to transcutaneously measure blood flow velocity in arterial vessels within the wrist.
After blood flow to the lower arm was temporarily interrupted in these tests, the measured blood flow velocity in arterial vessels within the wrist was reduced to an insignificant level within less than seven seconds.
The completed human-use study validated the CA Rescue™ Watch’s capability for the detection of cardiac arrest, demonstrating its effectiveness for emergency cardiac arrest rescue services.