Advances That Regrow Babies’ Hearts; Pediatric surgeons are developing a new strategy to tackle one of cardiology’s most challenging congenital defects

July 22, 2013, 7:30 p.m. ET

Advances That Regrow Babies’ Hearts

Surgeons develop a new strategy to tackle one of cardiology’s most challenging congenital defects.

RON WINSLOW

Pediatric surgeons are developing a new strategy to tackle one of cardiology’s most challenging congenital defects: babies born with only one heart ventricle. The doctors are enlisting the body’s own regenerative powers in an effort to grow the missing ventricle or strengthen the remaining one. At Boston Children’s Hospital, doctors are beginning to see the fruits of a 10-year effort to use biology instead of new technology to help children born with the condition, called hypoplastic left heart syndrome, grow a second ventricle. Among 34 patients treated so far, 13 are now living with two working ventricles, according to Sitaram Emani, the surgeon heading the effort.Doctors at Mayo Clinic, Rochester, Minn., meanwhile, are looking to boost the functioning of the existing ventricle. They just started enrolling babies with the same defect in a 10-patient trial to see if stem cells taken from their own umbilical cords can stimulate the growth of heart-muscle cells and strengthen surgical repairs made to fix the defect.

Currently, standard treatment involves a series of three open-heart surgeries, developed over the last 30 years, to enable the children to survive with one ventricle. Together the new methods represent a novel effort to extend survival—and avoid or reduce the impact of complications from the surgeries that can emerge later in life. Though hard statistics aren’t available, 30% or more of children don’t survive to adulthood, Dr. Emani says.

“Our theory is that a newborn heart has amazing growth potential that we haven’t been able to harness because we haven’t traditionally thought about using that option,” Dr. Emani says.

Sherry and Charles Fitch decided to test the theory in 2006 after their yet-to-be-born son Harrison was diagnosed with the anomaly during an ultrasound exam near the end of Ms. Fitch’s second trimester of pregnancy.

An Internet search turned up information on the Boston Children’s program. Despite limited data on outcomes for saving the left ventricle, the Atlanta couple figured it was their son’s best shot.

“It was a hope,” Ms. Fitch says—to give her son “a chance to have a full two-ventricle heart.”

Of some 40,000 U.S. babies born each year with a congenital heart defect, nearly 1,000 have hypoplastic left heart syndrome, according to the U.S. Centers for Disease Control and Prevention. It arises from a genetic anomaly that prevents the left ventricle—the heart’s main pumping chamber—from developing properly.

In a normal heart, the left ventricle receives oxygenated blood from the lungs to deliver to the brain and other body organs. Oxygen-depleted blood returns to the heart, collecting in the right ventricle, which pumps it to the lungs to begin the cycle again.

With only a right ventricle, the heart can’t get enough oxygen-rich blood to the body. Without surgical repair, the defect is typically fatal within days or weeks after birth. A heart transplant is an option for some, but the donor supply is so tiny that few babies can survive the wait.

The three surgeries—known as the Norwood, the Glenn and the Fontan—are intended to enable the right ventricle to take over for the left one. The Norwood is performed soon after birth, the Glenn between four and six months later and the Fontan generally by age 3.

But because the right ventricle isn’t built for the long-term high-pressure squeezing that propels blood through the aorta to the body, the repair often fails later in childhood or by early adulthood.

About a decade ago, with emerging research revealing the regenerative potential of the infant heart, Dr. Emani and his colleagues began to wonder if giving up on the left ventricle was a missed opportunity.

If in the initial surgery or prenatally they could unblock valves and other structures affected by the defect, they figured they could restore blood flow to the heart’s left side and perhaps cause the ventricle to grow.

There were plenty of perils—among them the possibility that the effort would put a successful single-ventricle repair at risk. “When we started doing this, people felt we were trying to poke a sleeping dog and [would] create more trouble than it’s worth,” Dr. Emani says.

But if it worked, the doctors figured children would fare much better growing up with two functioning ventricles instead of just one.

For Harrison Fitch, the prenatal diagnosis provided an early chance to tap into the body’s regenerative capacity. In a fetal procedure, Boston Children’s doctors successfully threaded a balloon into an opening the diameter of “angel-hair pasta,” Ms. Fitch recalls, and inflated it to open an obstructed heart valve. It began opening and closing, enabling blood to reach the left ventricle.

By the time Harrison was born, his left ventricle had begun to grow, but as expected, not enough to function on its own. Doctors proceeded with the three standard operations for a single-ventricle repair. But they also kept blood flow to the left ventricle.

One key strategy: In each of the children’s surgeries, doctors cut away fibrous tissue that builds in the left ventricle due to lack of sufficient blood flow. In some children, Dr. Emani says, that clearing of tissue “unleashed” the ventricle’s growth potential.

At age 4, several months after the third operation, Harrison underwent a fourth surgery—to end his reliance on a single ventricle and bring his left ventricle fully on line.

Now almost 7, Harrison plays T-ball, soccer and lacrosse. The fix isn’t ideal: He tires more easily than most kids, Ms. Fitch says. But “he’s healthy, he’s got a big personality, he’s smart. We couldn’t ask for more.”

So far, the approach has successfully rehabilitated the left ventricle in about one-third of cases. “We’re learning more about how to do this safely,” including improvements in postoperative care, Dr. Emani says.

Not all patients are good candidates. And until those who were treated reach adulthood, it won’t be known whether the strategy worked. That will take 15 years or more.

In the Mayo Clinic study, the focus isn’t on salvaging the left ventricle, but on helping the right one serve as the main pumping chamber. Umbilical-cord blood cells are harvested at birth and processed to separate out stem cells, which are then frozen.

Under the plan, the infant undergoes the first surgery shortly after birth. If all goes well, the stem cells will be injected directly into the heart during the second operation four to six months later.

The theory is that this “would stimulate more heart cells to grow or regenerate and make the existing cells stronger,” says Harold Burkhart, a pediatric heart surgeon at the clinic. “The hope is it would delay the need for a transplant or the onset of a decrease in function of the single ventricle.”

Whether that will happen is far from certain, but if it works, both Drs. Burkhart and Emani, whose efforts are separate, are intrigued by the possibility they may be complementary. Seeding a rehabilitated left ventricle with stem cells could ultimately enhance the chances of success for that approach.

About bambooinnovator
Kee Koon Boon (“KB”) is the co-founder and director of HERO Investment Management which provides specialized fund management and investment advisory services to the ARCHEA Asia HERO Innovators Fund (www.heroinnovator.com), the only Asian SMID-cap tech-focused fund in the industry. KB is an internationally featured investor rooted in the principles of value investing for over a decade as a fund manager and analyst in the Asian capital markets who started his career at a boutique hedge fund in Singapore where he was with the firm since 2002 and was also part of the core investment committee in significantly outperforming the index in the 10-year-plus-old flagship Asian fund. He was also the portfolio manager for Asia-Pacific equities at Korea’s largest mutual fund company. Prior to setting up the H.E.R.O. Innovators Fund, KB was the Chief Investment Officer & CEO of a Singapore Registered Fund Management Company (RFMC) where he is responsible for listed Asian equity investments. KB had taught accounting at the Singapore Management University (SMU) as a faculty member and also pioneered the 15-week course on Accounting Fraud in Asia as an official module at SMU. KB remains grateful and honored to be invited by Singapore’s financial regulator Monetary Authority of Singapore (MAS) to present to their top management team about implementing a world’s first fact-based forward-looking fraud detection framework to bring about benefits for the capital markets in Singapore and for the public and investment community. KB also served the community in sharing his insights in writing articles about value investing and corporate governance in the media that include Business Times, Straits Times, Jakarta Post, Manual of Ideas, Investopedia, TedXWallStreet. He had also presented in top investment, banking and finance conferences in America, Italy, Sydney, Cape Town, HK, China. He has trained CEOs, entrepreneurs, CFOs, management executives in business strategy & business model innovation in Singapore, HK and China.

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