Hypertrophic cardiomyopathy (HCM) is a complex heart condition that can lead to severe symptoms, including chest pain, lightheadedness, palpitations, fatigue, shortness of breath, fainting, peripheral edema, and abdominal bloating.
Around two-thirds of patients with HCM also develop left ventricular outflow tract obstruction, which can further exacerbate heart failure symptoms.
Alison Brann, MD, a cardiologist and HCM specialist at University of Utah Health’s Hypertrophic Cardiomyopathy Program, explains the significance of this obstruction.
“We call that left ventricular outflow tract obstruction, and it too leads to symptoms of heart failure,” she states.
Diagnosis of HCM is primarily conducted through cardiac imaging techniques, with normal heart wall thickness ranging from 10 millimeters or less.
HCM is diagnosed when the heart wall thickens to between 13 to 15 millimeters.
Dr. Brann warns, “When the ventricular wall gets to three centimeters or more, that’s very concerning.
It increases your risk for a dangerous heart rhythm that can lead to sudden death.”
Although only 1% of HCM patients are affected by this increased risk, clinicians consider multiple factors to assess overall patient risk, including family history, unexplained fainting incidents, heart monitor findings, heart muscle measurements, cardiac fibrosis amount, heart function status, and the presence of an apical aneurysm.
Genetic testing has revolutionized how families screen for HCM, especially when a mutation has been identified in a family member.
Up until recently, the standard approach was through periodic echocardiograms.
Now, genetic testing is the preferred method.
If individuals had genetic testing more than five years ago, Dr. Brann advises reviewing those results with a doctor to determine if re-testing might be necessary.
There are two main types of HCM: obstructive and non-obstructive, each requiring different treatment and management strategies.
In obstructive HCM, the thickened heart wall muscle reduces or blocks blood flow to the heart, leading to symptoms like chest pain and fainting.
Non-obstructive HCM also causes heart wall thickening, but it does not block blood flow.
Patients with non-obstructive HCM commonly report fatigue and fluid retention.
Among the two types, management of hypertrophic obstructive cardiomyopathy tends to be more straightforward.
Medications such as beta blockers, calcium channel blockers, disopyramide, or cardiac myosin inhibitors are commonly prescribed.
Interventional options include septal reductive therapies like septal myectomy surgery and catheter-based procedures such as alcohol septal ablation.
Notably, cardiac myosin inhibitors (CMI), which gained FDA approval in 2022, have demonstrated effectiveness in alleviating symptoms associated with obstructive HCM.
These treatments necessitate careful monitoring with regular clinical appointments and echocardiograms to ensure safe and effective dosing.
In contrast, managing non-obstructive HCM presents greater challenges.
According to Dr. Brann, “Non-obstructed HCM requires that we relax the heart.
Currently, there are no medications specifically to do that.”
Diuretics are often prescribed to manage excessive fluid retention, alongside medications to control blood pressure.
In cases where symptoms persist, a heart transplant might become necessary.
Regular monitoring is vital for individuals with HCM.
While initial assessments can include echocardiograms or cardiac MRIs, annual EKGs are recommended, with additional follow-ups every three to five years.
Previously, early studies suggested that HCM was a leading cause of sudden cardiac death during exercise, leading to many athletes being disqualified from sports.
However, recent insights indicate that this blanket disqualification may not be appropriate.
Alan Jacobsen, MBChB, a sports cardiologist and HCM specialist at University of Utah Health, emphasizes the changing perspective.
“We now know that not to be true, and unilaterally disqualifying athletes from play is the wrong approach,” he asserts.
Research has revealed that individuals with HCM who abstain from exercise may face higher risks of metabolic and cardiovascular diseases, without an increased risk of sudden cardiac death linked to higher intensity exercise.
Despite advancements, therapies do not eliminate all episodes of sudden cardiac death, which can occur during physical activity or at rest.
Consequently, it’s essential for active individuals and athletes to consult with an HCM specialist to better assess and manage their risks.
Currently, hypertrophic cardiomyopathy is a manageable condition with no definitive cure—yet.
Dr. Brann notes that ongoing studies into gene therapy for HCM could pave the way for potential breakthroughs in treatment and possibly a cure.
image source from：https://healthcare.utah.edu/healthfeed/2025/05/managing-most-common-inherited-disease-of-heart-muscle-hypertrophic
