Here’s a cozy, sensor-bedazzled cover that’s custom-tailored for your heart. For the first time ever, scientists have found a way to make multiple cardiac measurements simultaneously across the entire surface of a beating heart.
Previous sensors, which had to be glued or sewn to the heart’s surface, could only cover small areas. This new elastic silicon sheath completely envelops the heart, allowing it to measure and map various physiological parameters -- from temperature and electrical activity to mechanical strain.
Drawing from medical imaging scans, a team led by John Rogers from the University of Illinois at Urbana-Champaign used a 3D printer to create an anatomically accurate reproduction of a rabbit heart. Once they had the heart template, they embedded tiny instruments in a silicon membrane designed to fit snugly over the heart. The components include sensors that measure pH and temperature, along with LEDs for mapping and gold electrodes to stimulate the heart. The end result: a form-fitting silicon sheath that keeps sensors in place, yet remains flexible enough to not interfere with cardiac pumping.
As a proof-of-principle, the team tried out their 3D-printed membranes on isolated rabbit hearts in a perfusion chamber (that is, a heart that’s kept beating outside the body, ex vivo). They were able to conduct a variety of experiments, which include electrical stimulation and measuring heart rhythm and changes in pH and temperature (two important things to monitor during surgical procedures).
In theory, the design’s flexibility would allow operations that not only measure but also control heart function -- such as regulating heartbeats like a pacemaker in the event of an arrhythmia.
So far, the device has only been used in isolated rabbit hearts, and for long-term, implanted devices, they’d need to work out issues with power supply and wireless data communication. "You have a beautiful spiderweb mesh of devices but you have to get power in and out to activate them," Rogers tells New Scientist.
The work was published in Nature Communications last week.
Image/video: Rogers et al.