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November 24, 2015

Pumped Up

Trumble Gets Funding To Help Heart Patients

By Daniel Tkacik /

heart pump

Heart pumps, which assist more than three million Americans with congestive heart failure each year, lead to a staggering number of infections — many of which are deadly.

To be exact, one in three patients with heart pumps develop an infection.

The National Institutes of Health (NIH) is keenly aware of the problem, as they just awarded a $1.2 million grant to Dennis Trumble to make a better, safer heart pump.

An assistant research professor of biomedical engineering, Trumble thinks he has a solution to the problem. Because the vast majority of heart pump infections occur at the spot where the pump’s power cord exits the body, Trumble believes the power cord should never exit the body, and instead draw power from an internal source. That power source, Trumble believes, could be a muscle in the patient’s back.

“The idea is to collect energy generated by the latissimusdorsi, a large muscle in the back. Then we can convert that energy into hydraulics that can be used to activate the heart pump,”Trumble said.

This muscle-powered heart pump would be an alternative to cardiac assist devices currently on the market, which are powered by external batteries or portable air compressors that patients have to carry around. In those pumps, drive lines typically pass through an area on the patient’s chest to connect the external power source to the pump inside the body.

“Drive lines for cardiac assist devices are fine for short-term applications, but in the long term they’re likely to cause infection, which is really bad news,” Trumble said. “These infections are very difficult to treat and can be very serious.”

What’s more, this muscle-powered heart pump will not come into contact with blood, removing the need for administering anti-coagulant medication that patients with traditional heart pumps are required to take.

While anti-coagulation medication reduces the chances of harmful blood clot formation, it can also cause patients to have a higher tendency to bleed.

“And if you don’t give patients enough anti-coagulants and you start to get blood clots forming inside the pump, they can grow, break off and migrate to elsewhere in the body to cause things like kidney damage, stroke or heart attack,” Trumble explained. “With the muscle-powered device that I am proposing, though, you avoid the need for anti-coagulants altogether.”

Apart from the risk of infection or complications associated with anti-coagulation therapy, heart pumps with external power require a lot of maintenance, which is a disruption to patients’ lives. In addition to carrying around a power source, patients with traditional heart pumps have to regularly clean drive lines and have all of the external hardware checked regularly.

Trumble says his muscle-powered device will not require much maintenance at all.

“The goal is to free the patient from having to do anything to maintain the device,” Trumble said. “Ultimately, I’d like this heart pump to be something that patients can forget they even have.”