Echocardiography is the gold standard in the diagnosis of HCM. An echo is a non-invasive test that uses sound waves to produce pictures on a monitor similar to a television.
This test usually takes about 30 to 40 minutes. The patient is required to either lie flat or on their side. The physician or technician places gel on the tip of a probe, then gently presses it against the skin of the patient moving the probe around the chest and abdomen.
Electrocardiogram (ECG)is a test that measures the electrical activity of the heart, noting the rate and rhythm while indicating the size of the chambers.
This is a non-invasive test which requires ten electrodes with wires attached to be placed on the chest and extremities. Lotions and creams should be avoided to aid adherence of the electrodes. This test will take approximately ten to fifteen minutes.
Magnetic Resonance Imaging (MRI)is a medical imaging technique used to visualize the structure and function of the heart. Contrast-enhanced MRI is used to assess myocardial damage associated with HCM. Not all HCM patients will require an MRI.
The procedure usually takes approximately one hour. Patients lie on their back, electrodes are placed on the chest and an intravenous access is obtained. Several sets of images are required in a tunnel-like enclosure. The patient is instructed to hold their breath periodically.
While imaging a breeze may be felt and a loud tapping or banging noise may be heard. Earplugs or headphones with music may be worn to reduce the noise. When the contrast media is injected, a warm sensation may be felt throughout the body.
24 hour Holter Monitor is a device the size of a pager, which is worn by a patient for either 24 or 48 hours. The monitor will continuously record the electrical activity of the heart. Holter monitor testing is a component of an annual evaluation. In addition, it may be used to evaluate episodes of tachycardia, dizziness, shortness of breath or chest pain.
An event recorder is similar to the 24 hour holter monitor in size, but only records the patient’s rhythm when the episode button is pushed or if the rhythm is beyond set parameters. It is mainly used when symptoms such as shortness of breath, chest pain or palpitations are episodic. The event recorder is normally worn for a 30 day period.
Treadmill stress tests are used to assess the heart’s response to exercise. Ten electrodes with wires attached are connected to the patient prior to exercise.
Stress tests are recommended for several different reasons such as exertional chest pain, shortness of breath or lightheadedness with activity. A stress test may be ordered to evaluate an individual’s level of conditioning prior to sports participation or to identify an irregular rhythm that is produced by activity. Stress tests are also ordered routinely as a part of a yearly protocol for some patients.
The exercise portion of the test takes approximately 20 minutes. Sneakers and comfortable clothing should be worn. Patients are recommended not to eat two hours prior to testing, however, for early morning appointments a light breakfast is recommended. Patients should be well hydrated, but need to refrain from caffeinated beverages that day.
Stress echocardiogramcan be performed on either the treadmill or on a bicycle. This test allows the doctor to compare the patient’s heart function at rest and at maximum heart rate. The doctor performs an echocardiogram prior to exercising. The patient exercises on either the treadmill or the bicycle and once their maximum heart rate is achieved another echocardiogram is immediately performed.
The entire test takes about 45 minutes to an hour.
Sneakers and comfortable clothing are worn. Patients are recommended not to eat two hours prior to testing, however, for early morning appointments a light breakfast is recommended. Patients should be well hydrated, but need to refrain from caffeinated beverages that day.
Genetic testing is an integral part of our family screening program. It is a technique used to identify individuals at risk prior to developing HCM. Genetic testing allows us to reassure family members of those not at risk while supporting, educating and counseling those found to have the gene. In the past decade, researchers have recognized at least 12 genes causing hypertrophic cardiomyopathy all of which may vary in their clinical presentation. For example, family members carrying the same genetic mutation may have few or no symptoms while others may have moderate to severe symptoms requiring surgical intervention or transplant. The clinical spectrum of symptoms and expressions is expansive as evidenced in the pedigree chart below.
Once genetic testing has been recommended for your family an appointment will be made with our genetics team. A comprehensive evaluation, including blood samples, is performed. The patient’s financial responsibility is established prior to testing.
The first to be tested genetically is a family member with known disease. That individual is the “index” case. The blood is drawn and sent to a lab for DNA sequencing. The process takes approximately 6 weeks. If a mutated gene is found in the index case, it is recommended that all first-degree relatives (siblings and parents) be screened.