Dilated Cardiomyopathy Diagnosis

Our medical providers have the experience and expertise to assess whether your dilated cardiomyopathy is more likely to be acquired or to have a genetic cause. They provide a comprehensive evaluation that starts with a phone call with one of our advanced practice nurses who specializes in inherited cardiomyopathy. This call allows them to collect your health and family history and to make a personalized plan for the tests and records that will be needed for your appointment. 

The clinic appointment is a multidisciplinary team visit that includes the doctor, a cardiovascular nurse or advanced practice provider, and a genetic counselor. It involves a detailed assessment of your symptoms, cardiac tests, and family history. If a genetic cause is suspected, we offer genetic testing and expert interpretation of the results. Learn more about genetic testing, counseling, and evaluation for heart disease.

The process of diagnosing and treating dilated cardiomyopathy involves blood tests, imaging, and other tests. Our specialists provide expert interpretation using the latest technologies, many of which were developed or refined at Stanford:

• Cardiac catheterization: After placing a needle in a wrist or groin, we thread narrow tubes called catheters through vessels toward your heart. During cardiac catheterization, we may take X-rays after injecting contrast dye, a test called an angiogram. We may also take a small sample of heart muscle for biopsy.
• Computed tomography (CT) coronary angiogram: This innovative test provides another option for examining coronary arteries. Instead of immediately performing a conventional angiogram to look for blockages or narrowing, we create a 3-D image of your arteries. If the arteries are clear, you may not need a cardiac catheterization. We use the latest scanners for CT coronary angiograms, with accurate results and low radiation exposure.
• Cardiac magnetic resonance imaging (MRI): Magnets, radio waves, and a computer produce high-resolution still and moving images of the heart and its blood vessels. We can see heart valve abnormalities, and heart muscle damage with cardiac MRI. Additionally, we can also assess for the presence of scar tissue within the heart muscle, another marker for the disease.
• Echocardiogram (echo): Ultrasound, or sound waves, creates a moving picture of your heart. We use echocardiograms to gauge the size, shape, and function of your heart and its chambers and valves. At times, we may ease an ultrasound probe down the esophagus and closer to the heart in a test called transesophageal echocardiogram (TEE).
• Electrocardiogram (ECG): We use electrocardiograms to record the heart’s electrical impulses, collecting information about its rhythm to look for irregular heart rhythms.
  
• Holter and event monitors: Noninvasive wearable devices known as Holter monitors or rhythm monitors perform continuous electrocardiogram monitoring outside the hospital for a set period of time, up to 30 days. Event monitors are similar, though you trigger recording when you experience an arrhythmia or other abnormal heart sensation.
• Stress electrocardiogram (ECG) test: A stress ECG test checks your heart rhythm with an electrocardiogram while you exercise on a treadmill or stationary bicycle. It can assess for coronary artery disease or abnormal rhythms of the heart.
• Stress echocardiogram (echo) test: A stress echo is similar to a stress ECG test but also includes a heart ultrasound to take images of your heart before and after you exercise on the treadmill or stationary bicycle.
• Cardiopulmonary stress test (CPX): This highly specialized stress test uses a breathing mask to measure the oxygen and carbon dioxide levels of the air you exhale. You will also likely have an ECG during the test and, often, an echocardiogram before and after. This breathing mask gives us a very accurate assessment of your heart capacity and fitness. We use this information to tailor your medical recommendations and create a personalized exercise program for you. Cardiopulmonary exercise testing is a specialized test that is available only at certain centers.
• Genetic testing A blood or saliva test to identify variations in someone’s DNA may be recommended by a genetic counselor. Genetic testing can help to both diagnose an inherited heart condition and guide clinical recommendations for at-risk family members.