Hypertrophic Cardiomyopathy

Aesthetic Medicine Today

Hypertrophic Cardiomyopathy

What is hypertrophic cardiomyopathy (HCM)?
Hypertrophic cardiomyopathy (HCM) is a complex type of heart disease marked by
thickening of the heart muscle, left ventricular stiffness, mitral valve changes and
cellular changes.
•        Thickening of the heart muscle (myocardium) occurs most commonly at the
septum, just below the aortic valve. The septum is the muscular wall that separates
the left and right side of the heart. Problems occur when the septum between the
heart's lower chambers or ventricles is thickened. The thickened septum may cause a
narrowing that can block or reduce the blood flow from the left ventricle to the aorta -
a condition called "outflow tract obstruction." The ventricles must pump much harder
to overcome the narrowing or blockage. This type of hypertrophic cardiomyopathy
may be called:
o        Hypertrophic obstructive cardiomyopathy (HOCM)
o        Idiopathic hypertrophic subaortic stenosis (IHSS)
o        Hypertrophic Cardiomyopathy (HCM)

Hypertrophic cardiomyopathy may also cause thickening in other parts of the heart
muscle, such as the bottom of the heart called the apex, right ventricle, or throughout
the entire left ventricle.
•        Stiffness in the left ventricle is a sign of hypertrophic cardiomyopathy that
occurs as a result of the thickened septum. The left ventricle also is unable to
normally relax and fill with blood. The stiffness in the left ventricle causes pressure to
increase inside the heart.
•        Mitral valve changes: When the outflow tract is narrowed, blood rushes
through the passageway toward the aortic valve (like a tight garden hose nozzle),
dragging the leaflets of the mitral valve with it. The mitral valve normally functions to
keep blood flowing in one direction from the left atrium (upper heart chamber) to the
left ventricle. However, the increased force of blood caused by hypertrophic
cardiomyopathy pulls the valve open and may cause blood to leak backward (called
regurgitation) into the left atrium.
•        Cellular changes, or changes in the cells of the heart muscle cells occur with
hypertrophic cardiomyopathy. Through a microscope, the cells appear disorganized
and irregular (called "disarray") instead of being organized and parallel. This disarray
may impact the electrical signals traveling through the heart and contribute to
ventricular arrhythmia (a type of abnormal heart rhythm).

Who is affected by hypertrophic cardiomyopathy?
HCM affects an estimated 600,000 to 1.5 million Americans, or one in 500 people. It is
more prevalent than multiple sclerosis, which affects one in 700 people.

HCM is the most common cause of sudden cardiac death in people under age 30.
HDCM may be best known for its role in cardiac arrest and subsequent death in some
young professional athletes.

What causes HCM?
HCM can be:
•        Inherited: HCM may be inherited, caused by an abnormality in the gene that
codes the characteristics for the heart muscle. When the gene defect is present, the
type of HCM that develops varies greatly within the family. In addition, some people
who have the HCM gene may never develop the disease.
•        Acquired: HCM my be acquired, the result of high blood pressure or aging.
•        Unknown: In other instances, the cause of HCM is unknown.
Because the cause of HCM varies, it is frequently difficult to identify a high-risk
population.

What are the symptoms of HCM?
Many people with HCM have no symptoms or only minor symptoms, and live a normal
life. Other people develop symptoms, which progress and worsen as the heart
function worsens. Symptoms can occur at any age and may include:
•        Chest pain or pressure that usually occurs with exercise or physical activity, but
also may occur with rest or after meals.
•        Shortness of breath (dyspnea) and fatigue, especially with exertion. These
symptoms are more common in adults with HCM and are most likely caused by backup
of pressure in the left atrium and to the lungs.
•        Syncope (fainting or passing out) affects about 15 to 25 percent of HCM
patients. Syncope with HCM may be caused by irregular heart rhythms, abnormal
responses of the blood vessels during exercise, or no cause may be found.
•        Palpitations (fluttering in the chest) due to abnormal heart rhythms
(arrhythmias), such as atrial fibrillation or ventricular tachycardia. Atrial fibrillation
occurs in about 25 percent of those with HCM, and increases risk for blood clots and
heart failure.
•        Sudden death occurs in a small number of patients with HCM.

How is HCM diagnosed?
Echocardiogram is the most common test used to diagnose HCM, as the characteristic
thickening of the heart walls is usually visible on the echo. Other tests may include
blood tests, electrocardiogram, chest x-ray, echocardiogram, exercise stress test,
cardiac catheterization and magnetic resonance imaging (MRI).

Your primary care physician can provide a referral to the Acute Response Testing
Center for a testing to determine the cause of your HCM.

How is hypertrophic cardiomyopathy treated?
The type of treatment prescribed depends on:
•        Whether there is narrowing in the out-flow tract (the path blood travels to
leave the heart)
•        How the heart is functioning
•        Patient's symptoms
•        The age and activity level of the patient
•        The presence of arrhythmias

Treatment is aimed at preventing symptoms and complications and includes risk
identification and regular follow-up, lifestyle changes, medications and procedures as
needed.

Risk Identification
It is important to identify the small number of patients with HCM who are at higher
risk for sudden cardiac death, so preventive measures can be taken. People with
HCM who have a higher risk for sudden death include:
•        Those who have family members who had sudden cardiac death
•        Young patients with several episodes of syncope (fainting)
•        Those who have an abnormal blood pressure response with exercise
•        Adults who have a history of arrhythmia with fast heart rate
•        Those with severe symptoms and poor heart function

If you have two or more risk factors for sudden death, your doctor may prescribe
preventive treatments such as antiarrhythmic medications or an implantable
cardioverter defibrillator (ICD). Most people with HCM have a low risk for sudden
cardiac death. Talk to your doctor about any personal concerns.

Medications
Often, medications are used to treat symptoms and prevent further complications.
Medications help relax the heart and reduce the degree of obstruction so the heart
can pump more efficiently. Beta-blockers and calcium channel blockers are two
classes of medications that may be prescribed. If you have an arrhythmia, your doctor
may prescribe medications to control your heart rate or decrease the occurrence of
arrhythmias. Your doctor will discuss which medications are best for you.

It is important to know:
•        the names of your medications
•        what they are for
•        how often and at what times to take them

You may be told to avoid certain medications, such as nitrates because they lower
blood pressure, or digoxin, because it increases the force of the heart’s contraction.
Antibiotic medications are prescribed to prevent bacterial endocarditis, a potentially
life-threatening condition.

Procedures: septal myectomy, ethanol ablation, pacemaker, ICD
Septal myectomy
During this surgical procedure, the surgeon removes a small amount of the thickened
septal wall to widen the outflow tract (the path the blood takes) from the left
ventricle to the aorta. Myectomy is considered when medications are not effective in
treating HCM. This frequently eliminates the mitral valve regurgitation. This procedure
has a high percentage of positive results.

Ethanol ablation
This procedure, also called septal ablation, is performed in the cardiac catheterization
laboratory. First, the small coronary artery that supplies blood flow to the septum is
located during a cardiac catheterization procedure. A balloon catheter is inserted into
the artery and inflated. A contrast agent is injected to locate the thickened septal
wall that narrows the passageway from the left ventricle to the aorta. When the
bulge is located, a tiny amount of pure alcohol is injected through the catheter. The
alcohol kills the cells on contact, causing the septum to shrink back to a more normal
size over the following months, widening the passage for blood flow.

Implantable Cardioverter Defibrillators (ICD)
ICDs are suggested for patients at risk for life-threatening arrhythmias or sudden
cardiac death. The ICD is a small device placed just under the skin and is connected
to wire leads that are threaded through the vein to the heart. An ICD constantly
monitors the heart rhythm. When it detects a very fast, abnormal heart rhythm, it
delivers energy to the heart muscle to cause the heart to beat in a normal rhythm
again.

For patients with non-obstructive HCM
Non-obstructive HCM symptoms may be treated with medications. If heart failure
occurs, treatment is aimed at controlling it.

Lifestyle changes:
Diet:
Drinking at least six to eight, 8-ounce glasses of water a day is important, unless
fluids are restricted. In hot weather, you should increase your fluid intake.

Fluid and sodium restrictions may be necessary for some patients if heart failure
symptoms are present. Ask your physicians about specific fluid and dietary guidelines,
including information about alcoholic beverages and caffeinated products.

Exercise:
Your doctor will tell you if you may exercise or not. Most patients with HCM are able to
do noncompetitive aerobic exercise. Heavy weight lifting is not recommended.

Regular follow-up Visits:
Patients with HCM should have an annual follow-up visit with their cardiologist to
monitor their condition, unless more frequent appointments are needed. Follow-up
appointments may be more frequent when HCM is first diagnosed.

What is endocarditis?
Endocarditis occurs when germs (especially bacteria) enter your blood stream and
attack the lining of your heart valves, causing growths on the valve, holes in the
valve or scarring of the valve tissue, most often resulting in leaky heart valves.

Prevention of Infection:
People with HCM may have an increased risk for developing infective endocarditis.
Those at risk should follow these precautions:
•        Tell all your doctors and dentist you have HCM. They should prescribe
antibiotics to prevent an infection before performing any procedure that may cause
bleeding (dental, respiratory, and gastrointestinal (GI) procedures). Ask your doctor
about antibiotic guidelines.
•        Call your doctor if you have symptoms of an infection, such as temperature of
more than 101 degrees Fahrenheit or 38.4 degrees Celsius.
•        Take good care of your teeth and gums.
•        Ask your doctor if you need to take endocarditis preventions.