The smallest pacemaker ever made, injectable and compatible with the fragile hearts of newborns, lends itself to non -invasive and precise interventions.
A smaller pacemaker than a rice grain, injectable with a syringe without the need for invasive interventions, is activated in response to a bright impulse and dissolves in the body when no longer needs. The scientists of the Northwestern University (United States) designed it, thinking especially to the fragile and minute heart of the babies came to the world with congenital problems, but it is suitable for hearts of all measures. The peculiarities of the pacemaker, the smallest ever made, are explained in an article on Nature.
First it helps you and then dissolve. “About 1% of children were born with congenital heart defects,” explains cardiologist Igor Efimov, co -author of the study. «The good news is that these children they only need temporary pacemakers after an intervention. In about 7 days, most of the patients’ hearts are repaired. But those seven days are of crucial importance. Now, we can position this pacemaker on a child’s heart and stimulate it with a light, kind and wearable device. And no additional intervention is needed to remove it ». For the moment, scientists have shown the effectiveness of the tiny pacemaker on various animal models and human hearts of deceased donors.
Risky removal. Many adult patients also need temporary solutions to stimulate their hearts to beat regularly after an intervention, because they are waiting for a permanent pacemaker or to regain the heart to a regular activity. The problem of these temporary systems is that i stimulation threads Inserted in the patient’s heart muscle and connected to an external device come out of the body: they can move, they can create infections or be at the origin of blood clots. During the removal, there is the risk that they damage the tissues and cause internal bleeding: in 2012, the astronaut Neil Armstrong would have died precisely for this type of complication.
The previous ones. Precisely in response to this type of criticality, in 2021 Efimov and colleagues had developed a pacemaker capable of dissolving in the body How do the sutures do surgical after a pre -established number of days. Thin, flexible and light, it did not need batteries or threads, but it was still a little too large: 2.4 cm diameter, too much for babies, too much to be implanted in a non -invasive way. The fault of the type of communication used to activate it – the communication of proximity or NFC (Near -Field Communication), the same integrated in mobile phones – which required an antenna only in part miniaturizable.
Signals of light. To drastically reduce the size, scientists have thought of stimulating the heart thanks to A system based on light impulses. The pacemaker, which is just 3.5 millimeters long and 1.8mm wide, accompanies a soft and wireless wearable device that is positioned on the patient’s chest to measure the frequency of heartbeats. If an irregular beat is identified, the Wearable device sends an impulse of infrared light That penetrates the fabrics and, passing through the skin, the chest case and muscles reaches the heart, controlling its beat.
Electrical circuit. As a battery it is used the Galvanic cella model that allows you to convert chemical energy into electricity. The pacemaker uses two different metals as electrodes to deliver electrical impulses to the heart. The electrodes, in contact with the patient’s body fluids, form a battery. Chemical reactions flow electric current and stimulate pulsations.
«The heart requires a small amount of electrical stimulation. By minimizing the dimensions, we significantly simplify the system procedures, We reduce trauma and risks for the patient And, thanks to the dissolutionary nature of the device, we eliminate any need for secondary surgical extraction procedures »clarifies John A. Rogers, the pioneer of the bioelectronics that led the development of the device.
Possible developments. Precisely the reduced measures of the pacemaker will allow, ideally, to integrate arranges on other medical devices, such as cardiac valves, or to refine the synchronization of the heartbeat by arranging several pacemakers in various points of the heart. A different type of light could help manage Every single pacemaker independently. Coming for example to a better control of the arrhythmias.
