Nuclear cardiology: Why it’s important for your heart health

Nuclear cardiology is an accurate, noninvasive way to test for heart disease. It’s most commonly a stress test that measures the heart’s blood flow and pumping function. Advances in technology ensure only a small amount of radiation exposure.

More than 500,000 people die each year from heart disease, making it the leading cause of death in the United States. Also known as coronary artery disease, this narrowing of the heart’s blood vessels with fatty plaque deposits in the arterial walls blocks blood flow. This causes symptoms such as chest discomfort, angina, shortness of breath, and, potentially, a heart attack. That’s why it’s vital to get a proper diagnosis of heart disease, and one of the best ways to do that is with nuclear cardiology.

It may sound like something from science fiction. But nuclear cardiology is a common, noninvasive test that detects problems with myocardial blood flow as well as the heart’s pumping function, says Joy (Juwono) Sutedjo, MD, a cardiologist at Pacific Medical Centers in Seattle, Washington.

“Basically, it’s a type of stress or rest-and-stress test,” says Dr. Sutedjo, who is board-certified in nuclear cardiology and other cardiovascular imaging techniques. “The stress can be achieved by exercise, such as walking on a treadmill. If the patient is unable to exercise maximally, such as is often the case with an older patient or someone who has problems with the hips or knees, the stress is safely created with medication.”

When a patient comes in for a nuclear cardiology test, a small amount of imaging agent is introduced into the bloodstream. Then the patient is scanned with a gamma camera, which can detect the imaging agent. If there is a significant blockage or narrowing of the coronary artery, the heart muscles may not get enough blood during the exercise or chemical stress test. This decrease in blood flow can be detected by the camera images.

The nuclear component is part of the imaging agent, Dr. Sutedjo says. “We use a radio isotope, which is a radioactive material, in a very small amount,” she says. “With the advances in nuclear cardiology, we have been able to minimize the amount of radiation a patient receives. It is similar to a CAT scan of the chest.”

Nuclear cardiology has been around for several decades, and the past few years have seen developments that not only minimize radiation exposure but also help physicians study how the heart muscle pumps blood. This is called a MUGA test. Dr. Sutedjo says it can also be used with cancer patients while they are on chemotherapy or radiation therapy to ensure their heart is safe during treatment.

There are other types of stress tests, but nuclear cardiology is especially recommended for patients with moderate to high risk of heart disease. That’s because nuclear cardiology is one of the most sensitive, advanced tests available, Dr. Sutedjo says. Patients with lower risk may do a treadmill test that skips the nuclear component, at their physician’s discretion.

“Nuclear cardiology is a very good test to diagnose heart disease without doing an angiogram, which is an invasive procedure with risks,” she says. “Heart disease can be a silent killer, where a patient doesn’t have symptoms but has significant heart disease. Nuclear cardiology is recommended for patients with risk factors such as age, diabetes, hypertension, smoking, high cholesterol and family history of heart disease or stroke, or patients with abnormal EKG results. Nuclear cardiology can be a very valuable tool because it is noninvasive and has great accuracy in diagnosing heart disease and determining the extent of it.”

Nuclear stress tests can be ordered by a primary care provider or other non-cardiologist physician for patients who have the risk factors for heart disease. Learn more about the Nuclear Cardiology Department at Pacific Medical Centers.