Wearable Ultrasound Patches Monitor Heart Health
Tracking heart health is getting a major upgrade. Engineers have created a wearable ultrasound patch the size of a postage stamp that provides continuous, real-time images of the human heart. This breakthrough allows doctors to monitor cardiac function during a patient’s daily routine, moving life-saving technology out of the hospital and into everyday life.
The Engineering Behind the Stamp-Sized Ultrasound
The traditional ultrasound machine is heavy, bulky, and requires a trained technician to hold a wand against your chest. Engineers at the University of California San Diego completely re-imagined this process. Published in the scientific journal Nature in early 2023, their research details a soft, stretchable patch that measures just 1.9 by 2.2 centimeters.
To create a device this small, researchers combined liquid metal electrodes with a highly flexible polymer called a silicone elastomer. Inside this soft matrix sits an array of tiny piezoelectric transducers. These transducers generate and receive the sound waves needed to map the internal structures of the body. Because the materials stretch and move with human skin, the patch stays firmly attached even when the patient is sweating or exercising on a stationary bike.
Breaking the Limits of Traditional Echocardiograms
When a cardiologist wants to see how well your heart pumps blood, they usually order an echocardiogram. This test provides a fantastic view of your heart valves and chambers. However, an echocardiogram only provides a snapshot in time. It captures how your heart behaves while you are lying still on a clinic bed.
Heart problems often hide during resting conditions. Abnormalities in blood flow or pumping strength might only show up when a patient is walking up stairs, feeling stressed, or carrying heavy groceries. The new wearable ultrasound patch solves this blind spot. It can stick to a patient’s chest for up to 24 hours, taking continuous video of the heart as it pumps in real-world conditions.
The ultrasound waves from this tiny device can penetrate up to 14 centimeters deep into human tissue. This depth is more than enough to capture high-resolution images of the left ventricle, which is the main pumping chamber of the human heart.
Key Cardiac Metrics Tracked in Real-Time
Continuous imaging is only helpful if it provides actionable medical data. The UC San Diego team designed their patch to capture the exact same metrics that cardiologists rely on in standard hospital tests. The device automatically calculates several critical measurements.
- Stroke Volume: This is the amount of blood pumped out of the left ventricle during every single heartbeat.
- Cardiac Output: This metric measures the total amount of blood the heart pumps in one minute.
- Ejection Fraction: This percentage shows how much blood the left ventricle pumps out with each contraction. A normal ejection fraction is usually between 50 and 70 percent.
By tracking these numbers over a full day, doctors can spot early signs of heart failure, monitor patients recovering from a heart attack, or evaluate how well a new blood pressure medication is working.
The Role of Artificial Intelligence
Taking ultrasound images continuously for 24 hours creates a massive mountain of data. A human doctor cannot realistically sit and watch 24 hours of black-and-white ultrasound video to find a brief moment of abnormal pumping.
To handle this data overload, the engineering team built a custom machine learning algorithm. The artificial intelligence processes the continuous stream of images, automatically identifies the borders of the heart chambers, and calculates the heart’s pumping volume frame by frame. The AI system essentially does the tedious measurement work in real-time. This allows doctors to quickly review a summary chart showing the patient’s cardiac output throughout the day rather than scrubbing through endless video files.
Current Limitations and Future Wireless Models
While the current prototype is a massive step forward, it is not yet ready for the local pharmacy shelf. Right now, the patch itself is tiny, but it must be connected via flexible cables to a computer system that powers the transducers and processes the data.
The primary goal for the next phase of development is to make the entire system fully wireless. The research team is working on integrating a miniaturized battery and a wireless transmitter directly onto the patch. A spinoff company called Softsonics has already been formed to help commercialize this technology. Once the device goes wireless, a patient will be able to wear the patch under their clothes and beam their heart data directly to a smartphone app.
Beyond heart monitoring, this exact same ultrasound technology can be applied to other parts of the body. Doctors could eventually use similar patches to monitor the liver, track blood flow in the deep veins of the legs to prevent blood clots, or continuously check fetal development during high-risk pregnancies.
Frequently Asked Questions
What is a wearable ultrasound patch? It is a small, flexible device that sticks to the skin like a bandage and uses sound waves to create live images of internal organs. The most recent breakthrough is a stamp-sized patch designed to monitor heart function continuously for up to 24 hours.
How deep can the ultrasound patch see inside the body? The patch developed by UC San Diego engineers can penetrate up to 14 centimeters into the body. This is deep enough to capture clear images of the heart chambers, major blood vessels, and other central organs.
Is the ultrasound patch completely wireless? Not yet. The current prototype requires flexible cables connected to a computer to process the heavy data load of live video. However, engineers are actively developing a fully wireless version with a built-in battery and transmitter.
What heart conditions can this patch detect? By measuring stroke volume and ejection fraction over a long period, the patch can help doctors detect early signs of heart failure, monitor cardiovascular disease progression, and evaluate a patient’s risk of a heart attack during daily physical stress.
When will the wearable ultrasound patch be available to patients? The technology is currently in the testing and prototyping phase. Researchers are working through commercialization via companies like Softsonics, but it will take a few years of clinical trials and FDA approval before it is widely available in hospitals.