AssetID: 54642191
Headline: RAW VIDEO: Scientists Create 'World's Smallest' Pacemaker
Caption: Engineers at Northwestern University in Illinois have developed an ultra-small pacemaker that can be non-invasively injected into the body via a syringe. Although capable of functioning with hearts of all sizes, the pacemaker is particularly suited to the delicate hearts of newborns with congenital heart defects. Measuring smaller than a single grain of rice, the pacemaker is designed to work alongside a small, soft, wireless, wearable device that attaches to a patient’s chest. When an irregular heartbeat is detected, the wearable device emits a pulse of light to activate the pacemaker. These pulses penetrate the skin, breastbone and muscles to regulate the heart’s rhythm. Designed for temporary use, the pacemaker dissolves naturally once it is no longer required. As all components are biocompatible, they break down harmlessly in the body, eliminating the need for surgical removal. The findings were published today in the journal Nature. The study demonstrated the device’s effectiveness across large and small animal models, as well as in human hearts from deceased organ donors. Professor John A. Rogers, a leading expert in bioelectronics at Northwestern, led the development of the device. “To our knowledge, this is the world’s smallest pacemaker,” he said. “Temporary pacemakers are crucial in paediatric heart surgeries, and miniaturisation is essential in reducing the burden on the body.” Professor Igor Efimov, an experimental cardiologist who co-led the study, highlighted the motivation behind the work. “Around 1% of children are born with congenital heart defects, and many only require temporary pacing after surgery. Most hearts self-repair within a week, but that short period is critical. With this tiny pacemaker, we can provide essential support without additional surgery to remove it.” Professor Rogers and Professor Efimov collaborated with colleagues at Northwestern University, Dartmouth College, and the University of Chicago. Many patients require temporary pacemakers after heart surgery to regulate heart rate during recovery or while awaiting a permanent device. Currently, surgeons attach electrodes to the heart muscle during surgery, with wires extending outside the chest to connect to an external pacing box. When no longer needed, the pacemaker is removed, which can lead to complications such as infection, bleeding and damage to heart tissue. Professor Efimov pointed out the risks associated with this method, citing the case of astronaut Neil Armstrong, who suffered fatal internal bleeding when pacemaker wires were removed after bypass surgery. To address these issues, Rogers and Efimov previously developed a dissolvable pacemaker, first introduced in Nature Biotechnology in 2021. This version was lightweight and flexible, eliminating bulky batteries and wires. By adjusting the material composition and thickness, researchers could control how long the device remained functional before dissolving. While the earlier dissolvable pacemaker was successful, cardiac surgeons requested a smaller design better suited for non-invasive implantation, particularly in infants. The original device relied on near-field communication, similar to smartphone payment technology, which required a built-in antenna. Professor Rogers explained: “Our original pacemaker worked well, but the size of its antenna limited miniaturisation. Instead of a radio frequency scheme, we developed a light-based system to activate and control the pacemaker. This significantly reduced the size.” The researchers also reimagined the power source. Instead of using near-field communication, the new pacemaker operates via a galvanic cell, which converts chemical energy into electrical energy. When placed in the body, biofluids interact with metal electrodes to create an electrical current that stimulates the heart. The device uses infrared light, which penetrates deeply and safely into the body. If a patient’s heart rate drops below a certain threshold, the wearable device detects the change and automatically activates an LED. The light flashes at a frequency that corresponds to a normal heart rate. “Infrared light penetrates the body well,” said Professor Efimov. “If you shine a torch against your hand, you can see the glow through the other side. Our bodies are excellent light conductors.” Despite its tiny size—measuring just 1.8mm in width, 3.5mm in length, and 1mm in thickness—the pacemaker provides the same level of stimulation as a full-sized device. “The heart requires only a small amount of electrical stimulation,” said Professor Rogers. “By reducing the size, we simplify implantation, minimise trauma and eliminate the need for additional surgery.” Because of its small size, multiple pacemakers could be placed across the heart to provide more sophisticated synchronisation. This approach could improve cardiac function and even help treat arrhythmias. “We could deploy several tiny pacemakers across the heart and control each one independently,” said Professor Efimov. “This could lead to better synchronisation and even integration with other medical implants, such as heart valve replacements.” Professor Rogers added: “This pacemaker can be incorporated into almost any implantable device. We’ve demonstrated its integration with heart valve replacements to assist recovery after surgery. This is just one example of how we can enhance traditional implants with advanced stimulation.” The technology could also have broader applications in bioelectronic medicine, including nerve and bone healing, pain management and wound treatment. The study, Millimetre-scale, bioresorbable optoelectronic systems for electrotherapy, was supported by the Querrey Simpson Institute for Bioelectronics, the Leducq Foundation and the National Institutes of Health.
Keywords: feature,video,photo,pacemaker,medicine,doctors,tech,technology
PersonInImage: