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Photo courtesy Clemson University

The National Institutes of Health (NIH) has awarded Naren Vyavahare, Hunter Endowed Chair and professor of bioengineering at Clemson University, more than $1.5 million over four years to develop durable bioprosthetic heart valves (BHVs).

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Photo courtesy Clemson University

Naren Vyavahare is shown in a Clemson University lab. The CU research is taking place at Rhodes Hall, using "Star Trek"-worthy gadgetry: infrared spectroscopy, atomic absorption spectrophotometer, etc.

CLEMSON — What goes into five years? The laughter, love, tough lessons and small moments that help paint a person’s life.

Naren Vyavahare is hoping to provide heart valve transplant patients with five more years. Vyavahare, a professor of bioengineering at Clemson University, is pushing medical technology to its next plateau with a valve design featuring plastic and polyester.

The design is a right turn from the current valve replacement du jour: aortic valves from pigs, which are used in thousands of human heart valve replacement surgeries each year. Pig valves are used because pig hearts are similar in size and structure to that of humans.

But the procedure has a distinct weakness.

An estimated 50 percent of pig valve transplants fail within five to 15 years of install due to calcification, causing tears in the replacement and wrecking blood flow. In addition, the chemical used to fix damaged valve replacements, glutaraldehyde, has remained the same for decades.

“(Glutaraldehyde) makes tissue biomechanically strong, reduces its immunity and stabilizes it against enzymatic attack in the body,” Vyavahare said. “However, during our research for the last 10 years, we found that glutaraldehyde does not stabilize all components of the tissue such as elastin — which gives elastic properties — and glycosaminoglycans — they form jelly within the tissue giving tissue compressive strength. As these components leach out, tissue becomes weak and can tear without mineral deposition.”

When pig valve transplants wear out, it’s usually a muted experience (if regular checkups are maintained). Patients feel shortness or breath and fatigue; there’s no dramatic, chest-exploding episode.

Heart valve replacement is now the second-most frequently performed cardiac surgery in the U.S., after coronary interventions. Yet, the current procedure is limited to patients 60 years old and older. Vyavahare would like to make the operation suitable for younger population, even 25 to 30 years olds, and child-bearing-age women. But first he must significantly increase durability of bioprosthetic valves (BHVs).

“Adding even five years of functional life to BHVs through improvements in cross-linking technology would have a huge clinical impact,” Vyavahare said.

A $1.5 million National Institute of Health (NIH) grant is fueling Vyavahare’s efforts. But artificial heart innovation, for all its life-giving power, moves at the speed of snoring. Advancements in the field take decades, with years of research and clinical animal testing. That takes piles of money. Even with significant groundwork, there’s no guarantee technology will work with humans.

“You have to wait for 10 years or more after human use to see if the improvements actually worked,” Vyavahare said.

At Clemson, the 45-year-old Vyavahare is working with a 10-person team, including student researchers and post-doctoral fellows. The CU scientists are collaborating with counterparts at the University of Pittsburg and University of Minnesota.

Corresponding with Pittsburg and Minnesota via e-mail, cell phone and the occasional face-to-face visit, Clemson is providing the foothold science. The CU research is taking place at Rhodes Hall, using “Star Trek”-worthy gadgetry: infrared spectroscopy, atomic absorption spectrophotometer, etc.

After Clemson researchers improve valve stability, Pittsburg is charged with designing new equipment to study the biomechanics. In Minnesota, team members will implant the resulting devices into sheep for clinical trials.

A native of India, Vyavahare comes to Clemson after stints at Rutgers, Penn and the University of Michigan. Away from the lab, he seeks respite in travel and painting landscapes. Vyavahare arrived at heart valve research in 1993, after a background in chemistry. While working at Michigan, he was first exposed to heart valve research.

“That experience was so inspiring,” Vyavahare said.

Now Vyavahare wants to turn his own ideas into marvel. Perhaps along the way, a young research assistant will be moved to make the next miracle.