Fetal pacemaker: the technology that cures before birth

Fetal pacemaker: ready for the first experimentation

Everything is ready for the first human trial of a fetal pacemaker, to be implanted during pregnancy in children who have arrhythmia problems. A challenge undertaken by a team of researchers from the Children’s Hospital (L.A.) and a Biomedical Engineer at the University of Southern California about five years ago.

About the device

The micro pacemaker, which has the shape of a cylinder of less than 4 millimeters in length, will be used to treat fetuses affected by problems with cardiac conduction. It is a rare condition in which the heart beats too slowly to pump enough blood for the small body. These problems start to have an impact on development around week 28 and occur in the US on 500 children a year.
The most difficult detail to realize was finding a battery that was small enough to fit into a small pipe a few millimeters. The researchers designed a one-week lithium battery, which is recharged by exposing the mother to a radiofrequency. Once born the child can be operated to receive a normal pacemaker.

“It is necessary to make the pacemaker small enough to be fully implanted within the fetus and to do so with minimally invasive techniques”

explains Gerald Loeb, Biomedical Engineer at USC and co-leader of the project.

Future developments

The current device has undergone several tests in sheep fetuses, a conventional model for the study of fetal physiology. In 2015, the FDA granted the approval of the fetal device for humanitarian use. Now the team is ready to implant a personalized device as soon as a small patient will need it. Because the micropacemaker pulse parameters (charge, pulse duration, and rate) are fixed by the selection of the component values during fabrication, the stimulus intensity is also fixed. Future work will include collecting data to better understand the safety factor of the stimulus, the amount of excess charge that is applied to the tissue above threshold.
The refinement of the mini-pacemaker, whose use must prove to be safe both for the mother and the fetus, could offer the real opportunity to prevent spontaneous abortions and premature births related to these congenital anomalies.