Researchers and physicians seeking a worthy technological successor of the pacemaker have their eyes set on the “heart sock” — a thin, multifunctional membrane that fits the beating organ like, well, a sock.

The innovation, which consists of a silicon sheath studded with tiny sensors, can accurately measure a wide array of vital signs in within the organ, including temperature and electrical activity. According to developer John Rogers and his team at the University of Illinois at Urbana-Champaign, the finished design will also feature electrodes capable of regulating heartbeat and counteracting adverse events like heart attacks.  

For an accompanying study published in the journal Nature Communications, the heart sock was tested on isolated rabbit hearts as well as the heart of a deceased organ donor. In all experiments, the device returned detailed profiles in response to artificial changes in cardiac temperature and pH level. Rogers told reporters that, although human trials may be a long way off, doctors and researchers already recognize great potential in the technology.  

“We’re scientists of a very conservative mindset,” he said, speaking to National Geographic. “They have patients who are dying. They have a great appetite for trying out good stuff.”

That said, several challenges remain before the heart sock can enter research and clinical practice. For example, the team is currently looking at ways to dissolve the implant in the body once it is no longer needed. Finding the optimal way to power the electrodes embedded in the device has also proven problematic. "You have a beautiful spiderweb mesh of devices but you have to get power in and out to activate them," Rogers told the New Scientist.

The first pacemaker was implanted in 1958 by Åke Senning, a Swedish cardiovascular surgeon.  Today, about 3 million people worldwide rely on the device to offset complications like arrhythmia, or irregular heartbeat. Thanks to the heart sock’s unique design, this type of technology may not only be improved, but extended to other parts of the human body too. "Whether you exploit it in full 3D or not, being able to curve around a surface is very valuable," he said of the innovative design. "The idea could be applied to any organ."

Source: Xu L, Gutbrod SR, Bonifas A, Rogers JA, et al. 3D multifunctional integumentary membranes for spatiotemporal cardiac measurements and stimulation across entire epicardium. Nature Communications. 2014.