Hypertrophic cardiomyopathy is a condition in which a portion of the heart muscle is abnormally thick. This can make it harder for blood to flow into and out of the heart and cause other problems.
One of the main blood-pumping chambers of the heart, called the left ventricle, is affected in hypertrophic cardiomyopathy. The walls of this heart chamber become abnormally thick for unknown reasons. The abnormal thickness of the walls makes the heart chamber stiff, which makes it harder for blood to flow in and out of the heart.
The cause is of hypertrophic cardiomyopathy is unknown, but most cases are thought to be inherited. Someone who has a close relative with this condition has a much higher risk than others do.
The symptoms of hypertrophic cardiomyopathy can be absent, mild, or severe. Sometimes, sudden death occurs in a person with no history of symptoms. More commonly, the following symptoms occur, usually during or shortly after exercise:
After a complete history and physical, the healthcare provider may order tests to help confirm the diagnosis of hypertrophic cardiomyopathy. These tests may include:
There are no known ways to prevent hypertrophic cardiomyopathy.
The long-term effects of hypertrophic cardiomyopathy are hard to predict. There is an increased risk of abnormal heartbeats, called arrhythmias, and heart infections, called endocarditis.
Hypertrophic cardiomyopathy also causes an increased risk of sudden death. This risk is not related to how severe the person's symptoms are. It is not known why sudden death occurs, but in most cases it is thought to be due to arrhythmias.
Hypertrophic cardiomyopathy is not contagious, but it may be inherited by an affected person's children. Genetic counseling may be helpful to couples with a family history of this condition.
The goals of therapy are to reduce symptoms of hypertrophic cardiomyopathy and prevent death. Because sudden death has been linked to exercise, strenuous exercise should be avoided, whether or not the person has symptoms.
Heart medications are often used to reduce symptoms such as chest pain, palpitations, and fainting. Commonly used medications include atenolol, amiodarone, and diltiazem.
A type of pacemaker device called a defibrillator may also be used for dangerous abnormal heartbeats. Minor surgery is needed to put a defibrillator in place.
For someone with severe symptoms that cannot be controlled by medication, open heart surgery may be advised. The surgery involves removing part of one of the thickened walls of the heart.
All medications have possible side effects. For example, atenolol may cause sleepiness and erectile dysfunction. Diltiazem may cause stomach upset or swelling in the legs. Surgery carries a risk of infection, bleeding, and allergic reaction to anesthesia.
The exact course of hypertrophic cardiomyopathy is hard to predict. Treatment is usually needed for long periods of time, sometimes for life.
Any new or worsening symptoms should be reported to the healthcare provider. Regular visits to the healthcare provider allow ongoing monitoring for arrhythmias or worsening of the hypertrophic cardiomyopathy. Repeat electrocardiograms, or ECGs, and echocardiograms are often used to help with monitoring.
Author:Eric Berlin, MD
Date Written:
Editor:Duff, Ellen, BA
Edit Date:09/21/00
Reviewer:Adam Brochert, MD
Date Reviewed:07/03/01
Merck Manual, 1999
Current Medical Diagnosis and Treatment, 1996
Harrison's Principals of Internal Medicine, 1991