Small Robots as an Alternative to Open-Heart Surgery

Small robots have been developed that can reduce treatment of a heart infection, which normally takes several weeks, to a single day.

Treating a heart infection is not an easy task. Patients usually receive antibiotics for weeks through intravenous injection, and if this method is not effective, open heart surgery is proposed as a high-risk option. Now, Johns Hopkins University engineers may have found a better way to treat this disease.

According to DigitalTrends, this group has created small magnetic robots called "millibots" whose width is about the size of a pencil tip and the length of a grain of rice. These robots are designed to deliver medicine directly to the infected tissue of the heart.

What is the problem with the current methods of treating heart infection?

Endocarditis, or infectious inflammation of the inner layer of the heart, is a disease that affects about 50,000 people in the United States every year.

The usual method of treating this disease is to prescribe antibiotics through intravenous injection for several weeks; But the drugs are diluted on the way to the heart, and in many cases they cannot effectively eliminate the infection.

In such situations, doctors have to increase the dose of the drug, which increases the risk of toxic side effects, or go for risky open heart surgery.

How do these little robots work?

These robots work in groups and in cooperation with each other. The first robot, called the "needle module," attaches to the heart tissue near the site of infection and remains in place to provide the attachment site for the second robot.

The second robot, called the "pharmaceutical module", carries the antibiotic. This robot is connected to the needle module using magnetic force and gradually releases the medicine at the site of infection.

Because the needle module remains in place, doctors can replace the drug module with a fresh one to administer subsequent doses.

Neither of these two robots have batteries or motors. Instead, a series of electromagnetic coils placed outside the body will remotely control the robots by generating magnetic fields. These fields are similar to the magnetic fields used in magnetic resonance imaging (MRI) machines.

The senior author of this research says: A microrobot can be inserted into the body with just a small hole caused by the needle, and this process can be done without causing infection or bleeding.

From human heart model to pig heart tissue

So far, researchers have been able to guide these robots in models of the heart that simulate the structure of the human heart; Even when the simulated blood flow was against their movement. The technology has also been tested on pig heart tissue.

If all goes according to plan, this process may take about 10 minutes. If two stages of drug administration are needed, this time can reach about an hour.

Researchers hope that this method can reduce the treatment period of four to six weeks to one day or even less.

The next step for the research team is to test the robots on heart models that beat and contract like a real heart. This step can help to check the performance of robots in conditions closer to the real body condition.

Possible applications of this technology are not limited to the treatment of heart infection; Researchers say that in the future, the same technology can be used to deliver anti-cancer drugs directly to the desired location.