You’ll Always Be in My Heart
A tiny, wearable ultrasonic sensor can continuously image the heart to detect problems early, before they become serious.
Heart health is a critical issue that affects millions of people worldwide. The World Health Organization estimates that 17.9 million deaths occur each year due to cardiovascular diseases, making it the leading cause of death globally. Heart disease can have a significant impact on a person's quality of life. It can lead to disability, reduced life expectancy, and an increased risk of death. In addition, heart problems can also lead to a range of other health complications, such as stroke, kidney failure, and lung disease.
Monitoring heart health is crucial in identifying and managing potential problems early on. Early detection and management of heart problems can have a significant impact on reducing the risk of heart disease and improving overall health outcomes. According to the American Heart Association, controlling blood pressure and cholesterol can reduce the risk of heart disease by up to 80%.
But heart problems are often asymptomatic for a long period of time, so those with problems do not seek help. And since present equipment, like echocardiograms, are bulky, expensive, and require trained technicians to operate, continuous monitoring is not an option for most people. Moreover, certain methods, like the CT or PET, expose patients to radiation and must be used sparingly. For these reasons, subclinical and transient conditions are rarely spotted, delaying critical early treatments.
A new wearable ultrasound sensor for cardiac imaging developed by researchers at the University of California San Diego may soon upend what we currently know about cardiac monitoring. The size of a postage stamp, the monitor can be worn on the chest for up to 24 hours at a time to assess the structure and function of the heart. It is comfortable, unobtrusive, and can operate as one goes about their normal, daily activities — even during exercise. Since many conditions only manifest themselves during periods of exercise, this feature of the device is of particular importance.
The tiny patch, which is said to be as soft as human skin, is adhered to the skin on the chest. It is capable of transmitting ultrasound waves into the body, and also receiving the reflections as they bounce back. As it currently stands, that data is transmitted to a nearby computer through a bundle of wires, however, the team has already developed a wireless module that will untether the device in the near future. The sensor measurements are then processed with a deep learning model that can determine the three most important factors used in assessing heart health: stroke volume, ejection fraction, and cardiac output.
Currently, the processing algorithm only works for people that were included in the training dataset. It is believed that by creating a larger training dataset, or by implementing a few-shot learning approach, the model may be generalizable to a much larger population.
Looking ahead further, the researchers note that their wearable sensor could be adapted to image other deep tissues, like the spine and liver. As previously mentioned, they have also developed a wireless module to eliminate the present cable tether, but they are also thinking one step beyond that — on-device processing. By miniaturizing the computational resources and integrating them with the skin patch, it could become truly transparent to those being monitored.