This is an archived article that was published on sltrib.com in 2011, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.
The symptoms came on suddenly in the final stretch of Allyson Gamble's first and only pregnancy.
She had become so breathless and fatigued, she could hardly manage the stairs at work. Initially she wrote it off as the flu, but a doctor recommended IV fluids, which caused her body to swell dangerously.
She was rushed to the hospital, where she was diagnosed with peripartum cardiomyopathy (PPCM), a rare and mysterious form of heart failure that Utah researchers are closer to understanding after discovering a genetic mutation — the first-ever linked to the disease.
Gamble was able to deliver a healthy, now 10-year-old boy, Benjamin, after spending three weeks in intensive care. A heart transplant spared the young mother's life.
But doctors can't explain why Gamble, 42, and previously healthy pregnant women like her suffer a sudden, catastrophic breakdown of the heart.
Science is still a long way from understanding the origins of pregnancy-related heart failure, said Benjamin Horne, director of cardiovascular and genetic epidemiology at Intermountain Medical Center in Murray.
Horne says the mutation identified by a team of researchers that he led at Intermountain, the University of Utah and VA Hospital "gives us a road map that tells us where to look in the human genome for more information." A study detailing their findings was just published in the online edition of Circulation: Cardiovascular Genetics.
"Someday this may lead to early testing during pregnancy that can identify women who are at risk," said Horne. "We may be able to reduce or even prevent some of the complications of this disease."
Although rare, PPCM is a leading cause of pregnancy-related deaths, affecting about one of every 3,000 to 4,000 healthy American women. Most patients are treated with medicine, but about 10 percent require a heart pump or new heart.
"It was really hard for me to understand I could be that sick," recalled Gamble, who said she had walked into the hospital the day she learned her heart had nearly quit.
Cases have been reported of PPCM in mothers and daughters and sisters, but Gamble doesn't know of anyone in her family with the disease.
It can occur in women of any race and age but is more common with older women, twin pregnancies, expectant moms with pre-eclampsia (high blood pressure) and women of African ancestry. But there are no well-defined risk factors.
Much of the mystery is due to a lack of patient data, explained James D. Fett, co-director of the PPCM Network, a national registry of 30 hospitals that share patient data.
"There's always the question of what's genetics and what's environmental," Fett said. "The Utah study is one of the firmer findings that there's a genetic predisposition, which may work in combination with environmental triggers."
Horne's team tapped a registry of about 100 patients maintained at Intermountain, which feeds the national registry.
Researchers started by gathering DNA samples from 41 women in their 20s and 30s who had suffered from PPCM. They also took samples from 49 mothers over the age of 75 with no known heart problems and sent the samples to a lab in Iceland.
"The initial testing was a fishing expedition," said Horne. "We didn't know what genes or mutations in the human genome lead to PPCM, so we were just going to test anything out there and see what popped up."
The testing showed that about two-thirds of the women with PPCM shared a genetic mutation on the chromosome 12.
To confirm the findings, Horne's team performed two more rounds of testing on different sets of patients. The results of both mirrored the first: Women with PPCM were about 2 1/2 times more likely than healthy patients to carry the mutation.
The group is pursuing additional research to build on the discovery, including a clinical study to explore genetic testing. Horne is also contributing patients to a large federally funded trial spearheaded by the PPCM Network that will look into autoimmune factors, or the immune system acting against the heart.
Gamble donated her blood to the registry. She hopes the sample figures into medical advances but has no way of knowing whether it was used in the Intermountain study.
Early diagnosis improves patients' chances of full recovery, making it possible for women to get pregnant and deliver again.
That's not an option for Gamble, executive director of Utah's Capitol Preservation Board.
"Early on, I couldn't chase after Ben. I was always tired. There was no throwing a backpack on and hiking," she says of the changes wrought by PPCM. "But I'm grateful for the second chance. There's not a sunrise or sunset where I don't stop to say, 'Wow.' If nothing else, it's made my little family extremely purposeful and grateful."
Data mining
O Researchers say patient data is key to finding causes and cures for rare diseases like peripartum cardiomyopathy. Information about the condition and how to sign up for a national patient registry is available at: