Advanced tools for cardiovascular imaging can help detect heart disease or other heart problems and can put patients on an effective treatment course.
Cardiologists use three main types of imaging: the cardiac CT scanner, nuclear myocardial perfusion imaging (nuclear stress test) and echocardiography.
Heart and vascular disease represents the number one cause of death and disability in women (as well as men). Sudden cardiac death is all too frequently the first sign of heart disease. These statistics are real and frightening. They beg the question "what can be done?"
The answer is PREVENTION. We now have at our disposal the knowledge that healthy lifestyle changes and proper medical management of those at risk can substantially change the outcomes in heart and vascular disease.
Early detection is the key to prevention. The earlier we can detect and treat heart disease, the better the outcome. Standard risk factor screening can be supplemented with a new and powerful risk assessment tool called calcium scanning. Calcium in the walls of arteries is a marker for plaque and correlates well with the risk of heart attack and death. When detected with a quick CT scan this information can be used to determine how aggressive treatment should be or provide reassurance for those not at high risk. For those with the suspicion of heart disease cardiac CT angiography (with dye) can produce striking pictures of the heart and arteries that can diagnose the presence or absence of disease with astounding accuracy- often years before it can be detected with stress testing. Armed with accurate risk information you and your physician can team up to change your outlook with regard to heart attack and stroke.
Cardiac CT Scanner and CT Angiography
The cardiac CT scanner allows cardiologists to get a full view of every angle of the heart and vascular system. The images are gathered by rotating an X-ray beam system 360 degrees around the body while scanning detailed cross-sections of the heart. A powerful computer then compiles the images into a series of three-dimensional, semi-transparent images.
CT-angiography, one of the procedures performed with the cardiac CT scanner, is used to diagnose the presence and severity of coronary artery disease.
“What we get from this scanner is a complete three-dimensional scan of the heart, a virtual trip through the heart using a noninvasive, outpatient procedure,” Dr. Turner said. “This cardiac CT scanner in many instances allows us to gauge the health of the coronary artery system as effectively as an invasive procedure performed in the hospital, and is actually superior to cardiac catheterization in its ability to look at the anatomy of the heart.”
According to Dr. Turner, this is an exciting, new technique that will have expanded uses over the next several years.
Nuclear Stress Test
A nuclear stress test is a gold standard test for looking at abnormalities of blood flow to the heart. It is used by doctors to assess the risk of and presence of blockages in the coronary arteries.
The test consists of two parts. The first involves injecting a tracer into the blood stream and then electrodes are placed onto the patient’s chest. The cardiologist then has the patient exercise on a treadmill at gradually increasing speeds and inclines. During this period of time the cardiologist monitors the patient’s heartbeat for abnormalities.
After the exercise portion of the exam is complete the second phase of the test begins. Special cameras that can detect the previously injected tracer are used to take pictures of the heart. The tracer is carried by blood throughout the body and the camera is able to detect the amount of blood flow from the heart.
An echocardiogram is simply an ultrasound of the heart. The echocardiogram was the first medical application of ultrasound technology, and when combined with a Doppler examination, cardiologists are able to assess blood flow.
"Echocardiograms allow us to look at abnormalities of valves and heart function or blood flow,” Dr. Turner said
Calcium Scan of the Heart—A self-referred exam.
A fourth test is available and patients don’t need a physician’s referral for this one. A calcium scan of the heart is an useful tool for someone who has no known indications of coronary disease. A calcium score, or the amount of plaque in the arteries, is an excellent way to predict the risk of a future heart attack.
“If a patient has a very low calcium score then their ten year risk of a heart attack is very low,” said Dr. Turner. “Conversely, if a patient has a high calcium score (more than 400) then their ten year risk of a coronary event may be as high as 20 percent.”
A calcium scan is independent of and can be used in addition to traditional risk factors to predict a heart attack.
Early Detection Saves Lives
With this imaging technology, cardiologists are able to add new meaning to the words “early detection.”
These imaging tests often complement each other and one may suggest a problem that another test can confirm.
“Just like many other diseases, early detection can mean the difference between life and death,” Dr. Turner added. “It is especially important when dealing with heart disease, however, because often people with heart disease have few visible symptoms, if any at all.”