How Hypertrophic Cardiomyopathy Is Treated

Medically reviewed by Yasmine S. Ali, MD, MSCI

The primary treatment options for hypertrophic cardiomyopathy (HCM) are medications like beta-blockers and calcium channel blockers. Lifestyle changes can also help control HCM symptoms. If symptoms continue despite medical therapy, more invasive therapies like procedures or device installation may be recommended.

This article discusses HCM treatment, from medications to more invasive or surgical options.

Medications

People with HCM can have symptoms, such as chest pain, fainting, and lightheadedness, due to obstruction of blood flow out of the heart due to the thickened heart muscle. Medications are used to help with symptoms in HCM.

Beta-Blockers

Beta-blockers are the first-line treatment for symptoms of HCM.

Beta-blockers work by blocking beta receptors in the heart to decrease the heart's contraction and heart rate. This is helpful when symptoms of HCM are due to obstruction, because the thickened heart muscle blocks flow to a greater extent when the heart is pumping harder.

Beta blockers used to treat HCM include:

• Atenolol

• Bisoprolol

• Metoprolol

Beta-Blockers to Avoid

Some beta-blockers should be avoided in HCM because they can also cause vasodilation, or dilation of the blood vessels, which can worsen symptoms. Specific beta blockers that should generally be avoided in HCM include carevedilol and labetalol.

Calcium Channel Blockers

The calcium channel blockers verapamil and diltiazem may be used in place of beta-blockers in people who do not tolerate beta-blockers. People who experience unwanted side effects, like fatigue, from beta-blockers may better tolerate a calcium channel blocker.

Calcium channel blockers can be a good choice for people with asthma, since beta-blockers may worsen asthma symptoms.

Disopyramide

When beta-blockers and calcium channel blockers fail to control symptoms in HCM, disopyramide may be used.

This medication is a type of antiarrhythmic drug that also decreases the heart's contraction. Because it can also stimulate arrhythmias, it's not the first choice medication, but it can be helpful when other medications fail.

Mavacamten

Mavacamten is a new therapy that has been recently approved by the Food and Drug Administration (FDA) to treat symptomatic HCM. It decreases the heart's contraction by blocking myosin, a component of the heart muscle.

A Phase 3 clinical trial of mavacamten showed that in people with obstructive HCM, symptoms and exercise capacity were improved compared to placebo. However, compared to the more invasive treatments for HCM, it is not as effective at reducing severe obstruction in HCM.

Lifestyle Considerations

Symptoms from obstruction of blood flow in HCM can be worsened by exercise and dehydration. The following are important considerations for people with HCM that can help keep symptoms at bay.

• Stay well-hydrated and avoid dehydration

• Try a special diet

• Avoid alcohol and caffeine in excess

• Avoid spending time in saunas or hot tubs, which can contribute to dehydration and cause vasodilation and a drop in blood pressure

Talk to your cardiologist or healthcare provider before participating in strenuous exercise or competitive sports due to the risk of arrhythmia and sudden cardiac death (SCD). Most people are encouraged to exercise at moderate intensity.

Septal Reduction Therapy

Septal reduction therapy is a type of invasive therapy that aims to decrease the bulk of the thickened muscle to improve the obstruction of blood flow out of the heart.

Due to its invasive nature and risks, this type of therapy is generally reserved for people with severe symptoms despite medical therapy.

Septal reduction therapy may be done with alcohol septal ablation or septal myectomy.

Alcohol Septal Ablation

Alcohol septal ablation is an invasive therapy performed by cardiologists at specialized centers.

In this procedure, a catheter is used to enter the coronary blood vessel that feeds the thickened muscle in the heart, delivering alcohol that causes scarring. This results in thinning of the muscle with the purpose of relieving obstruction.

Alcohol septal ablation success is somewhat lower compared with septal myectomy. About 7% of the time, the obstruction is not entirely relieved, and further procedures or surgery may be required.

Septal Myectomy

Septal myectomy is a type of heart surgery performed in specialized centers.

During this surgery, an experienced cardiothoracic surgeon gains access to the heart and removes part of the thickened heart muscle to relieve obstruction. Abnormalities of other parts of the heart, such as the mitral valve, can be fixed at the same time if necessary.

While septal myectomy is effective at relieving the obstruction, the risks of performing surgery on the heart need to be considered. The choice between alcohol septal ablation and septal myectomy is based on a person's characteristics and discussion with their healthcare team.

Implantable Cardioverter Defibrillator (ICD)

One devastating complication of HCM is sudden cardiac death (SCD) due to dangerous arrhythmias, such as ventricular tachycardia and ventricular fibrillation.

Because of this, cardiologists may recommend the placement of an implantable cardioverter defibrillator (ICD), a device that monitors the heart rhythm and can deliver an electric shock to stop dangerous arrhythmias.

Certain risk factors increase the risk of SCD and can be an indication of an ICD:

• Recent unexplained fainting

• Family history of sudden cardiac death

• Findings from echocardiography, such as heart wall thickness of 3 centimeters or greater, weakness of the heart muscle, or an out-pouching of the heart wall known as an apical aneurysm

• Findings from cardiac MRI, such as extensive heart muscle scarring

• Findings on heart rhythm testing, such as periods of ventricular tachycardia

Summary

Hypertrophic cardiomyopathy (HCM) is a heart condition characterized by the thickened heart muscle. First-line therapy for HCM includes beta-blockers or calcium channel blockers. In addition, disopyramide may be used when first-line medical treatments fail, and a new medication called mavacamten can be considered for certain cases.

When medical therapy fails and symptoms are still present and severe, invasive therapy with either alcohol septal ablation or surgery may be recommended.

A Word From Verywell

Hypertrophic cardiomyopathy can be a stressful diagnosis, but your healthcare team can help find a treatment plan that controls symptoms, improves quality of life, and decreases risk of sudden cardiac death. The treatments for HCM have been used for decades, but newer medical therapies may be promising in the future.

Read the original article on Verywell Health.