(NEW YORK) -- Lisa Salberg has so far lost seven family members to an insidious heart disease -- a medical mystery that took four generations of tragedy to unravel.
Her great-great uncle, an Irish immigrant, mysteriously dropped dead at the age of 19 in a New Jersey iron mine a century ago. At 50, her great-grandmother died of "dropsy" -- an old-fashioned term for the accumulation of fluid associated with heart failure.
Salberg's grandfather had a heart murmur and died at 43. Her father missed a date with her mother because he had to administer CPR to his dying father.
Salberg's aunt died at 36 of "the flu." Another aunt died of a stroke at 52, and an uncle died of heart failure at 48.
Fast forward to the mid-1970s, when Salberg's sister Laurie was properly diagnosed with what looked like the cause of death of so many in her family: hypertrophic cardiomyopathy (HCM), or an enlarged heart.
Her death in 1995 hit Salberg the hardest, as she struggled to raise Laurie's children along with her own newborn daughter.
"I don't know how many there are, but we are dropping like flies," said Salberg. "The pieces came in dribs and drabs, and it took years to get the information imparted. There was no connecting the dots."
Their father was diagnosed with HCM in 1989 and died in 2008.
"It affected generations of people and it's everywhere in my family," said Salberg, 44, who got her diagnosis in 1979.
Salberg's now 17-year-old daughter, as well as Laurie's children, her niece, 28, and nephew, 30, also have HCM. Several cousins also have the disease.
Cardiomyopathy is a familial disease that primarily affects the muscle of the heart. With HCM, the normal alignment of muscle cells is disrupted, a phenomenon known as myocardial disarray. It also causes disruptions of the electrical functions of the heart and, depending on whether it obstructs the outflow of the heart from the left ventricle, can be obstructive or nonobstructive.
HCM is an autosomal dominant genetic condition, which means the mutation only needs to be passed down from one parent. Because cardiomyopathy is a spectrum of diseases, each person is affected differently.
The disease is "actually pretty common," affecting about 1 in 500 Americans, said Dr. Sripal Bangalore, assistant professor in cardiology at NYU Langone Medical Center in New York City. An estimated 600,000 Americans are living with the disease.
"A lot of people walking around lead a normal life into their 70s and 80s with no problems," he said. "At the other spectrum, young athletes die while playing sports."
Often there are no symptoms, so the disease is diagnosed by evaluating family history. Children at risk should have an echocardiogram to see if the heart muscle is enlarged. That must be repeated every five years until adulthood and is not always conclusive. Many doctors do not recommend genetic testing because of its complexity -- there are more than 1,000 genes associated with cardiomyopathy.
Treatments may include medications like statins, beta blockers and calcium channel blockers; surgery to burn away the thick part of the heart muscle; and implanted defibrillator devices.
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