Scientists at Northwestern University have developed the world’s smallest injectable pacemaker, marking a significant advancement in temporary cardiac care, especially for newborns with congenital heart defects. The device, smaller than a grain of rice, is designed to be inserted via a syringe and dissolve harmlessly in the body after use, eliminating the need for surgical removal. Engineered for temporary use, the pacemaker is tailored to provide critical cardiac pacing support during the immediate postoperative recovery phase in infants undergoing heart surgery.

According to John A. Rogers, a leading figure in bioelectronics at Northwestern, the device addresses a long-standing need in pediatric cardiology, where the size of existing devices has limited their utility in neonatal patients. The device operates in tandem with a wireless, flexible wearable system that adheres to the patient’s chest. This external unit monitors cardiac activity and, upon detecting irregular rhythms, emits light pulses that non-invasively activate the pacemaker. The light penetrates the skin, breastbone, and surrounding tissue to stimulate the implanted unit.
All components of the pacemaker are biocompatible and dissolve naturally into the body’s biofluids once they are no longer needed. This eliminates the requirement for a second surgical procedure to extract the device, reducing the overall physical burden on the patient, particularly important in fragile newborns. Igor Efimov, an experimental cardiologist at Northwestern who co-led the project, emphasized the device’s relevance to pediatric care.
World’s smallest pacemaker dissolves after use
He noted that approximately 1% of children are born with congenital heart defects and often require temporary pacing for only a few days post-surgery. The new pacemaker offers a non-invasive solution that aligns with this short-term need. The researchers highlighted that multiple units can be deployed simultaneously on the heart to achieve synchronized pacing. Furthermore, the system may be integrated with other implantable devices, such as heart valve replacements, to provide pacing support when complications like heart block arise.
Because of its size and dissolvable nature, the pacemaker is also suitable for broader medical applications. Rogers indicated the technology could be used to enhance existing implants and support recovery from a range of conditions by providing targeted stimulation. The innovation expands the potential for bioelectronic medicines beyond cardiac care, with possible applications in nerve regeneration, bone healing, wound treatment, and pain management. – By MENA Newswire News Desk.