New heart pump to provide temporary assist for infants, adults

November 9, 2010
This illustration shows a new type of heart pump inserted with a catheter to improve the survival rate for infants undergoing a series of surgeries to correct a deadly birth defect. The researchers are developing a "viscous impeller pump" for children born with univentricular circulation, a congenital heart disease that is the leading cause of death from birth defects in the first year of a child's life. Credit: Rose-Hulman Institute of Technology

Researchers have created a new type of heart pump inserted with a catheter to improve the survival rate for infants undergoing a series of surgeries to correct a deadly birth defect.

The researchers are developing a "viscous impeller pump" for children born with univentricular circulation, a that is the leading cause of death from birth defects in the first year of a child's life, said Steven Frankel, a Purdue University professor of mechanical engineering.

The innovation also might be used for temporarily treating adults with the disease.

The human heart normally contains two pumps, or : one circulates oxygenated blood throughout the body, and the other, less powerful, ventricle circulates deoxygenated blood to the lungs.

Babies born with the defect have only one functioning ventricle, but French surgeon Francois Fontan discovered more than three decades ago that the infants could survive on a single ventricle by restructuring the configuration of blood vessels called the inferior vena cava and superior vena cava. The infants must have a series of three open heart surgeries performed over a period of months or years because they are not be able to survive the shock of all three surgeries at once.

At least 30 percent of the babies do not survive the surgeries, called the Fontan procedures.

To improve the survival rate, Mark Rodefeld, a medical doctor and associate professor of surgery at the Indiana University School of Medicine, proposed in 2003 to provide a mechanical pump to assist the heart during surgery.

Steven Frankel, a Purdue professor of mechanical engineering, is creating a new type of heart pump (pictured on computer screen) for infants born with univentricular circulation, a congenital heart disease that is the leading cause of death from birth defects in the first year of a child's life. Credit: Purdue Mechanical Engineering file photo/Michael Black

Such an innovation would make it possible to perform all three surgeries at the same time, while also providing a temporary heart-assist technology for adults who've had the surgeries, Frankel said.

"A big advantage of this pump is that it gets delivered through the skin with a without ," said Frankel, who is working with Rodefeld and other researchers at the IU School of Medicine, the University of Louisville and the Rose-Hulman Institute of Technology's Rose-Hulman Ventures, which is developing a prototype of the pump.

The researchers have received a $2.1 million, four-year grant from the National Institutes of Health's National Heart, Lung and Blood Institute to continue developing the . The research also involves graduate student Jeffrey R. Kennington and Jun Chen, a Purdue assistant professor of mechanical engineering.

Researchers plan to implant the new pump into a four-way intersection where the inferior and superior vena cavae meet the right and left pulmonary arteries. Once inserted with a catheter, the pump can be dramatically expanded, forming a shape that resembles two cones joined at the base. The device spins at about 10,000 rpm, connected via a slender cable to a small motor outside of the body.

Frankel and graduate student Travis Fisher originated the design, applying concepts from textbook fluid dynamics developed a century ago by Hungarian engineer Theodore von Kçrmçn, founder of modern aerodynamics.

The researchers also found design inspiration from an unlikely source: cocktail umbrellas.

"A major challenge was, how do we get this into the body, and we thought of the cocktail umbrella," Frankel said. "It starts out flat and compact and then opens out with a similar shape, with upper and lower segments."

A pump is needed because relying on one ventricle reduces the heart's circulatory force.

"It's a weak circulatory system, so you don't get really good pumping into the lungs, and the oxygenated blood returning to the heart doesn't quite fill the ventricle to begin the cycle over again," Frankel said. "A patient right now who's walking around in their 20s, who had the surgery 20 years ago, may start having heart problems and need some support, either as a bridge to transplant or as a temporary means of support. This pump represents a way to do that in an outpatient setting. It is designed to be in the body for two weeks at most, almost like a disposable item."

The rotating device contains riblike grooves to efficiently pump blood. The design is promising because testing has shown that the rotating device causes minimal damage to red blood cells.

"Because it's larger than other experimental pumps, it doesn't have to spin as fast - a maximum of about 10,000 rpm compared to 50,000 for another experimental pump - so it causes less damage to blood cells," Frankel said. "It's like the gentle cycle in a washing machine."

Experiments at the University of Louisville that mimic the circulatory system show the degree of damage done to blood cells by the spinning pump is acceptable for clinical use. That work was conducted by U of L's Guruprasad A. Giridharan, an assistant professor in the Department of Bioengineering.

Related Stories

Recommended for you

Study shows stress could be just as unhealthy as junk food

October 16, 2017
We all know that a poor diet is unhealthy, but a new BYU study finds that stress may just as harmful to our bodies as a really bad diet.

Childhood poverty, poor support may drive up pregnant woman's biological age

October 16, 2017
Pregnant women who had low socioeconomic status during childhood and who have poor family social support appear to prematurely age on a cellular level, potentially raising the risk for complications, a new study has found.

Blood vessel 'master gene' discovery could lead to treatments for liver disease

October 16, 2017
Scientists have identified a key gene in blood vessels which could provide a new way to assess and potentially treat liver disease.

Chronic inflammation plays critical role in sustained delivery of new muscular dystrophy therapy

October 16, 2017
Macrophages, a type of white blood cell involved in inflammation, readily take up a newly approved medication for Duchenne muscular dystrophy (DMD) and promote its sustained delivery to regenerating muscle fibers long after ...

Worms reveal secrets of aging: Researchers discover a conserved pathway that controls aging

October 13, 2017
Investigators at Case Western Reserve University School of Medicine and University Hospitals Health System have identified a new molecular pathway that controls lifespan and healthspan in worms and mammals. In a Nature Communications ...

New study demonstrates importance of studying sleep and eating in tandem

October 13, 2017
A new study from scientists on the Florida campus of The Scripps Research Institute (TSRI) offers important insights into possible links between sleep and hunger—and the benefits of studying the two in tandem. A related ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.