Bethany and Hannah Keime, two sisters from Miami, thought they were "normal" high school students. Bethany was in an arts high school for dance, and Hannah played varsity basketball and participated in competitive dance. Then, they were both diagnosed with a chronic and deadly heart condition: hypertrophic cardiomyopathy (HCM).
HCM is an inherited disease in which the heart muscle gets thicker, which can make it harder for the heart to pump blood. About 1 in 500 people have it, though it's an underdiagnosed condition.
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"We never suspected, [and] unfortunately neither had our pediatrician," the women, who are now in their 20s, say. "We went to the cardiologist because our maternal aunt had gotten an HCM diagnosis and was told it could be genetic."
Understandably, they scoured the internet for more information. "All we found were stories of people our age who had died undiagnosed," they explain. "Death was listed as the most common first 'warning sign.'"
Ahead, cardiologists share what you need to know about this disease.
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Hypertrophic Cardiomyopathy Has These Symptoms -- Sometimes
As mentioned, people may die from this condition without even realizing they have it.
"Patients who are otherwise asymptomatic can present with cardiac arrest, which can be fatal," says Dr. Melissa Burrows, MD, a noninvasive cardiologist at Wellstar Health System.
It all comes back to what HCM causes: the thickening of the heart muscle. "The muscular thickening puts patients with HCM at a higher risk for sudden cardiac death and other serious heart events because it can obstruct blood flow through the heart and lead to irregular heartbeat, heart failure, stroke and more," adds Dr. Jeremy Pollock, MD, a cardiologist with the University of Maryland St. Joseph Medical Center.
Not every HCM patient is at risk for cardiac arrest, Dr. Burrows clarifies (and doctors can look at clinical factors to determine if an implantable defibrillator is needed). Statistically, around one percent of people with HCM die of sudden cardiac death annually. Treatment is key, so we'll get to that.
Some patients do have symptoms, however, so it's important (per usual) to pay attention to your body. Common symptoms include chest pain, shortness of breath, heart palpitations, fainting, exercise intolerance, swollen legs and feet, and dizziness.
Related: The Silent Symptom That Could Be a Sign of Heart Trouble
What's happening there, Dr. Pollock explains, is the heart can't pump blood as well as it should, so people with HCM have less oxygen-rich blood, and the body needs oxygen to produce energy.
"If you have these symptoms, try not to shrug them off as a normal sign of aging or overwork," he adds.
When To See a Doctor and What the Diagnosis Process Entails
If you have any of those symptoms or other cardiac symptoms, both cardiologists urge getting an evaluation. Additionally, if you have a family history of this condition, they urge you to get screened for it. The genetic risk is a whopping 50 percent.
"Early detection is key," Dr. Pollock tells Parade. "If caught early, your cardiologist can develop a care plan that includes careful monitoring and treatments that may be able to prevent serious complications."
Going to the doctor about a possible heart condition can be scary, so these cardiologists share what to expect with the diagnosis process. First, doctors will ask about your symptoms and family history. Then, they'll likely perform a physical exam, which includes an ECG. (An ECG, or electrocardiogram, measures your heart's electrical activity and rhythm through electrodes, which feel like stickers.)
If further evaluation is needed, you'll get an echocardiogram, which is an ultrasound that looks at the heart muscle and blood flow. A Holter monitor, cardiac MRI and stress test may also be used.
Who Can Have HCM?
It's important to emphasize that young and otherwise healthy people can have this disease. Case in point (other than the Keime sisters) is the former Miss Ohio, Lindsay Davis, who later championed a law around cardiac arrest training and wrote a book about her experience.
Further, HCM is the number one cause of cardiac death in young people.
"Younger people may feel the symptoms of HCM more severely, and -- as they are even less likely to be diagnosed and are generally more physically active -- are more likely to be putting, unknowingly, a strain on their heart that can be fatal to those with HCM," Dr. Pollock shares.
That may explain why we hear about athletes with the condition more often, even though they're not more likely to have it. "There are several high-profile incidents of sudden cardiac death in athletes, specifically basketball and football players [like Damar Hamlin]," Dr. Burrows says. "However, most HCM patients are not athletes."
Again, this condition isn't about age or health status -- it's a genetic condition. Cardiologists are clear: Anybody can have HCM. Don't be swayed into thinking you're not at risk because you don't have some of the risk factors.
How HCM Is Treated
The good news is that various treatments are available. It all depends on the particular case. Examples of treatment options, according to cardiologists, include:
And of course, paying attention to your daily habits is key. "As with all other heart conditions, it's the 'everyday' that has the biggest overall impact on your cardiac wellness," Dr. Pollock says.
He and Dr. Burrows encourage exercising, not drinking alcohol or smoking, good sleep hygiene, drinking plenty of water and eating heart-healthy foods to reduce the likelihood of complications.
For the Keime sisters, treatment looks like lifestyle changes, medications and getting a defibrillator. The latter shocked Hannah back to life when she went into sudden cardiac arrest in her sleep at only 17 years old.
The two are also continuing to monitor their health and be mindful of their limits. They've helped others, too, by co-founding HeartCharged, an online movement dedicated to preventing unnecessary heart-related deaths through education and support.
HCM Is Serious -- but There Is Hope
The sisters want to provide hope to other people with this condition.
"Life doesn't end with a diagnosis," they tell Parade. "Getting a diagnosis should lead to the appropriate treatment, which can give HCM patients the same mortality rate as others their age."
They urge people not to be afraid of getting a heart screening, and to know and report warning signs. After all, being at risk is more common than you might realize: One in 300 young people has an undiagnosed heart condition that puts them at risk for sudden cardiac arrest.
With that said, Dr. Pollock doesn't want people to worry too much. "Hypertrophic cardiomyopathy sounds scary," he says. "But it's important to remember that with careful monitoring and a comprehensive treatment plan, it's very treatable. Most people can live a healthy, long life with the diagnosis."