Advances in Heart Disease Screening

In just the past decade, technology has changed cardiovascular medicine – for the better. But no matter how high-tech the treatment becomes, it’s up to you to remain on top of your heart health.

First step: know your risk.

Determine your likelihood of experiencing a heart attack or other serious cardiac event in the next 10 years by answering these five questions. Based on the Framingham Heart Study, this assessment will help you calculate whether you are low, intermediate or high risk. (You’ll need to know your cholesterol level and blood pressure.)

What’s next?

We asked Christopher Kramer, MD, Professor of Medicine and Radiology and Director of UVA’s Cardiology Imaging Center, to explain who might need further cardiac screening and/or the latest advance in heart imaging. He also explains the different technologies being used for these procedures.

Who should be screened for coronary artery disease?

Screening is generally reserved for those who don’t have symptoms but who are at intermediate risk, based on the Framingham Study. This means you have a 10- to 20-percent chance of having a cardiac event in the next 10 years and you may have one or two cardiac risk factors but not several.

If you’re low risk, there may be no need to do anything further other than lifestyle improvements.

And if you’re high risk, then we know you need to make lifestyle changes and receive aggressive preventative treatment.

What types of screening may be recommended?

• Coronary Calcium Scoring is a direct measure of the amount of coronary atherosclerosis (hardening of the arteries) which is the major cause of heart attacks and strokes. This test uses a CT (computed tomography) scan to check for calcium build-up in the lining of the arteries. There is a low level of radiation exposure when undergoing this procedure. However, it is a frequently used screening method and has been studied in tens of thousands of patients.

• Ultrasound of the carotid (neck) artery measures its thickness and checks for plaque build-up. With this screening option, there is no radiation but getting accurate results takes a highly skilled operator.

Who might need further imaging?

More advanced imaging is for the patient who has symptoms of a heart condition. That may be chest pain, pressure or discomfort, especially with exercise; neck or arm discomfort or shortness of breath with exercise. Women have less typical forms of chest pain and symptoms so they can be more difficult to diagnose based on their symptoms alone. Stress testing with electrocardiography (ECG) alone is less accurate in women than in men. Imaging helps pinpoint areas of abnormal blood flow in the heart that may be causing these symptoms.

What are the types of imaging used?

• Nuclear imaging – SPECT (single photon emission computed tomography) looks at the blood flow to the heart muscle during exercise and while the patient is at rest. A solution is injected into the patient and images are taken of the heart after exercise. Or, if the patient can’t exercise, medicine can be given to increase blood flow to the heart. Four hours later, the images are repeated while the patient is at rest. UVA will acquire a PET (positron emission tomography) scanner this month, which can evaluate heart blood flow by using different radioactive tracers and has a higher accuracy and image resolution.

• Stress echocardiogram with ultrasound looks at the function of the heart muscle. Ultrasound images are taken when a person is at rest and during exercise. If the patient cannot exercise, then medicine is used to increase the work of the heart.

• MRI or magnetic resonance imaging evaluates the anatomy and function of the heart as well as the surrounding vessels. This test is often used for patients with advanced heart disease to uncover existing damage to the heart but also can be used for stress testing. The patient can’t exercise during this procedure so medicine is used.
• Computed tomography (CT) coronary angiography is a relatively new approach. It uses a contrast dye and radiation to provide direct imaging of the coronary artery rather than looking at blood flow. Researchers are still studying whether this direct coronary imaging or stress testing is the best initial approach to evaluate patients with symptoms.

What can we detect now because of advancing technology that we couldn’t five years ago?

Five years ago, we were just beginning to be able to obtain a direct image of the coronary artery with CT. CT angiography is the newest cardiac imaging test and it is still being studied to determine its ultimate role. All of the imaging modalities have improved over the last few years.

The type of screening and imaging recommended varies based on physician preference and from patient to patient, says Kramer. “Patients should consult with their physicians to determine the best course of action and talk through the advantages and disadvantages of the different types of imaging.”