Roadmap to a Diagnosis
It’s important to know that no one diagnostic test can determine your risk of heart disease; often several tests are required. As your own health advocate, know the reasons and risks of each test, and don’t be reluctant to ask your healthcare provider or technician questions.
When looking for clues about your heart health, your healthcare provider will probably start with blood tests. These tests often reveal risks for coronary artery and other heart disease and sometimes provide warnings for heart failure. Blood testing often requires fasting beforehand so be sure to check with your healthcare provider.
Blood profiles test for abnormal levels of:
- Fats (lipids) in your blood.
- Low-density lipoprotein (LDL) – the “bad” cholesterol – that causes the accumulation of plaque in your arteries.
- High-density lipoprotein (HDL) – the “good” cholesterol – helps clear your arteries of LDL.
- Triglycerides, another type of fat, that raise your risk of heart disease.
- Blood sugar (glucose) to detect the presence of diabetes and glucose intolerance (pre-diabetes).
- C-reactive protein to determine inflammation in your body. This test is given only to individuals who are at risk for heart disease and may be used with other blood tests to assess risk factors for heart disease.
- Complete blood count, thyroid studies, arterial blood gases.
A chest X-ray is a basic diagnostic tool that shows the size and structure of the heart and lungs. It can detect heart failure and reveal abnormalities in your heart, lungs and major blood vessels. Chest X-rays are simple, inexpensive and painless. Because this test exposes you to a small amount of radiation, let your healthcare provider know if you might be pregnant.
Calcium is usually contained in the fatty deposits, or plaques, that build up in arteries, making it an important predictor of coronary artery disease. Computed tomography is used to measure calcium in and around arteries.
Two CT scans are particularly effective:
Electron beam computed tomography (EBCT) is an ultra-fast CT scan that takes high-resolution, three-dimensional pictures of the heart as it is beating. Electron beams scan your heart as you lie on a special scanning table and progress through a doughnut-shaped scanner.
CT coronary angiography (CTA) involves an injection of a contrast dye into your arm to enhance the quality of the CT images. Coronary CTA helps measure the narrowing of coronary arteries and diagnose coronary blockages.
Also known as an angiogram, coronary catheterization tracks blood flow through your coronary arteries. A long, thin tube, or catheter, is inserted through your arm or leg artery and threaded into your coronary arteries. A dye is then injected through the catheter to highlight on an X-ray machine your blood flow in and around the heart. Because it is invasive and usually performed in a hospital, the procedure is recommended for women with severe symptoms, who do not respond to treatment or whose non-invasive tests are inconclusive.
An echocardiogram uses sound waves (ultrasound) to generate images of your heart and help your healthcare provider assess your heart’s pumping strength and detect damage to the heart chamber, valve problems and heart defects. Electrodes are placed on your chest and a wand (sound-wave transducer) is moved around your chest to pick up electrical activity. This test is simple and non-invasive, however, it does require fasting and medication restrictions beforehand.
An electrocardiogram (EKG or ECG) measures your heart’s electrical activity by placing small electrodes with adhesive pads to the skin of your chest, arms and legs. The test takes only a few minutes and is simple, safe and painless. An EKG measures your heart rhythm (fast, slow or irregular), detects inadequate blood flow to the heart, and identifies heart abnormalities, such as enlarged chambers or a heart defect. It can also confirm a heart attack, past or present.
Magnetic Resonance Imaging (MRI)
Magnetic resonance imaging is a testing technique that uses magnetic and radio-frequency waves to look at your heart throughout its blood pumping cycle. Clear, three-dimensional images help determine the structure and function of the heart, lungs, major blood vessels and area around the heart and detect blood vessel plaques and blockages as well as damage from heart attack or heart disease. The test is non-invasive, but requires you to lie on a table that moves through a magnet-shaped chamber. Electrodes are placed on your body for monitoring purposes and often an intravenous (IV) line is inserted into your arm to inject a dye to enhance the images.
Symptoms and evidence of coronary artery disease and other heart ailments often appear when the heart is working harder. Several diagnostic tests are designed to assess heart function and determine blood flow while “under stress”:
Exercise stress tests monitor your heart while you are walking on a treadmill or pedaling a stationary bike. How long you exercise, your blood pressure, your EKG and how you feel when you exert yourself are observed and recorded during the test.
Pharmacologic stress tests use a drug to reproduce the effects of exercise on the heart. This is a safe alternative for women who are not able to perform the required level of exercise due to older age, arthritis or excess weight.
Nuclear imaging, also called myocardial perfusion imaging (MPI), uses a small amount of a radioactive substance to produce images of the heart. A liquid “tracer” is injected into your bloodstream and monitored while you are at rest and during stress. Blood flow to your heart is measured to determine damage to the heart muscle or blood flow problems. Since this test exposes you to a very small amount of radiation, tell your healthcare provider if you think you might be pregnant.