New Sticker-Sized Pacemaker Uses Ultrasound Technology Instead of Traditional Wires

Researchers from MIT and USC develop a sticker-sized, non-invasive ultrasound pacemaker that regulates heartbeats without surgical wires. By utilizing sonogenetics to temporarily make heart cells responsive to sound waves, the device successfully paces hearts and resolves arrhythmias in modified rats. Tests on pig tissue suggest the ultrasound can penetrate human-sized chests safely, offering a potential future alternative to traditional pacemakers.

Ultrasound-based wearable pacemaker device

• ▪The non-invasive ultrasound pacemaker integrates a 64-channel phased-array transducer with modules for data collection, wireless transmission, and battery power.
• ▪A cloud-based artificial intelligence system reads heart rates, calculates targeting coordinates, and automatically adjusts the ultrasound beam of the pacemaker.
• ▪Researchers from MIT and USC developed a non-invasive ultrasound pacemaker that is roughly the size of a postage stamp and adheres to the skin.

Sonogenetics mechanism for cardiac control

• ▪In laboratory tests, ultrasound pulses synchronized the beating of approximately 75% of sonogenetically modified human heart muscle cells.
• ▪Ultrasound pulses trigger modified heart cells to open ion channels, allowing calcium to enter and causing the cells to contract.
• ▪Sonogenetics genetically modifies heart cells to temporarily produce proteins, making the cells responsive to ultrasound waves without permanently altering DNA.

Rat model experimental results

• ▪Rats without the genetic modification showed no response to the ultrasound pacemaker stimulation.
• ▪The ultrasound pacemaker increased heart rates in sonogenetically modified rats from 240 beats per minute to between 360 and 540 beats per minute.
• ▪The ultrasound pacemaker successfully restored normal heart rhythms in modified rats after researchers induced cardiac arrhythmias.

Clinical safety validation testing

• ▪Experiments on a pig heart under multiple tissue layers demonstrated that ultrasound waves can penetrate human-sized tissue to deliver 2 megapascals of pressure.
• ▪Safety evaluations in rats showed the ultrasound pacemaker operated within approved exposure limits, generated minimal heat, and caused no unwanted immune reactions.

Future therapeutic applications

• ▪Researchers plan to refine genetic material delivery, conduct trials in larger animals, and develop closed-loop systems with real-time sensing.
• ▪Researchers aim to develop the ultrasound pacemaker as a permanent alternative to implanted pacemakers and expand the technology to other organs.

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