Treatment for Hypertrophic Cardiomyopathy
Many patients with hypertrophic cardiomyopathy never need treatment. However, it is imperative that all patients be monitored by a cardiologist. Using the diagnostic techniques mentioned before, the cardiologist will determine the patient's individual need for monitoring, intervention and follow-up. The majority of patients that we see in clinic come because of certain symptoms. Fortunately, although there is no cure for the disease, there is much we can do to help.
Medicines
We use medicines to lessen the force of the heart contraction that many patients have. The aim is to reduce the build of pressure ('gradient') caused by blood pushing past the obstruction caused by the thickened heart wall. The two most common types of medicine used are beta-blockers, such as atenolol or metoprolol, and calcium channel blockers, such as verapamil.
Sometimes, patients with hypertrophic cardiomyopathy have an irregular heart rate caused by 'fibrillation' of the upper chambers. In this case, we sometimes use medicines to keep you in normal rhythm or to control your heart rate if you go into the abnormal rhythm. One such medicine is amiodarone.
We often recommend doses of antibiotics for certain patients when they visit their dentist. This is to prevent infection of the heart valves, which can happen in hypertrophic cardiomyopathy because the build up of pressure or the pattern of blood flow affects the valve and can make it susceptible to infection.
Myotomy and Myectomy ("Open Heart Surgery")
This is an operation where the thickened heart wall is surgically removed. It is used when medications are no longer able to control symptoms.
It is in fact very effective in relieving symptoms and improving quality of life. In fact, it is likely that myectomy also extends life: in one published series, 95 percent of patients who had surgery were alive 10 years later, whereas only 73 percent with similar symptoms who did not have surgery were alive.
Although the procedure is technically challenging, Stanford surgeons were pioneers of this operation and have performed hundreds of procedures since 1972.
Alcohol Septal Ablation ("Cardiac Catheterization Technique")
Cardiologists developed a less invasive method of reducing the outflow obstruction in hypertrophic cardiomyopathy. In this procedure, a few drops of an alcohol based solution are injected into a small branch of the main artery supplying the thickened heart muscle.
This causes part of the muscle to die (in effect, a small "~heart attack') and this in turn reduces the obstruction to blood flow.
This procedure is done entirely via a small incision at the top of the leg. Patients typically go home a few days later.
Not every patient will have an appropriate branch of their main artery which supplies only the thickened heart muscle and does not connect with other arteries.
Implantable Cardioverter Defibrillator ("ICD")
An important part of the work up for patients with hypertrophic cardiomyopathy is an assessment of the risk of dangerous heart rhythms. Fortunately, for those patients at risk, there is now the option of protection in the form of an implantable cardioverter defibrillator (ICD). This is a device a few inches in diameter which is inserted under the collar bone on one side. Leads are passed through veins to the heart so that the heart rhythm can be monitored at all times. If a dangerous rhythm is detected, the device will begin a series of treatments which culminate in an electrical "~shock' aimed at jolting the heart back into normal rhythm. It is a much less powerful shock than those administered by external defibrillators.
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The operation to implant the device takes about 1 hour and is usually done using local anesthetic and sedation. However, every device is then tested under general anesthetic by putting you briefly into a dangerous rhythm to confirm that the device can "~shock' you out of it. Some devices are also capable of pacing.
Pacemaker
A pacemaker can be implanted using a very similar procedure to that detailed above the ICD. Early trials of pacemaker therapy in hypertrophic cardiomyopathy suggested a significant benefit from simply changing the activation sequence of heart contraction. Although the pressure build up was decreased in most studies, it turned out that this did not translate to benefit for the patients, so pacing as a therapy is not routinely recommended. However, in certain subsets of patients, it can be helpful. Newer technologies may result in further trials of this approach.