What Nuclear Stress Testing Can Show About Your Heart’s Function

Your doctor may order a stress test for a number of reasons. First, if you show any symptoms of heart disease, including chest pain and/or shortness of breath, he may want to get a sense of how your heart functions under physical strain. The test’s results provide information about the underlying cause(s) of those symptoms so your doctor can administer prompt and effective treatment.

If you’ve already had a heart attack or been diagnosed with any form of heart disease, a stress test also allows the doctor to determine the effectiveness of your current cardiac treatment or learn if you’re able to return to exercising.

At Northwest Houston Heart Center, cardiologists Dr. A. Adnan Aslam and Dr. Roy Norman use different forms of stress tests to help them diagnose and treat your heart condition before it jeopardizes your health. Here’s what they want you to know about what the newer and more detailed nuclear stress test can show about your heart’s function.

What a stress test tells your doctor

A stress test tells your doctor how well your heart is functioning. The test pushes the heart to work harder than normal, so it needs to pump more blood to keep pace with the increased demand. If it can’t keep up, the test will reveal a lack of blood supply through the arteries that lead to the heart. The results also help determine the kind and level of physical activity that’s right for you.

Any form of stress test shows:

• If your heartbeat (pulse) is irregular
• If your heart gets enough blood during exercise
• If symptoms are heart-related
• Any abnormalities in blood pressure
• Any changes in heart rhythm (arrhythmias)
• Any abnormal electrical activity (important for effective chamber contractions)
• If your current heart-related medications are effective
• If you need further tests

If you experience chest pain or shortness of breath during the test, it may indicate you have coronary artery disease (CAD), a blockage in one or more of the arteries that feed the heart. To obtain that data, to confirm that your doctor may order another test to confirm or fix the problem.

Interestingly, a 2013 study presented at the American Thoracic Society conference suggested stress tests could also identify people who have obstructive sleep apnea (OSA), a disorder in which you temporarily but repetitively stop breathing during sleep. OSA can affect heart function, so the test might also flag those most at risk of experiencing life-threatening complications.

Exercise stress tests

By far the most common type of stress test is the exercise test. It’s sometimes called a treadmill stress test or a stress EKG because it uses a treadmill or stationary bike to stress the heart and increase its rate. The doctor monitors your heart’s electrical activity during the test.

You can expect to spend about 10-15 minutes exercising. You start at a slow pace, and the doctor increases the speed of the treadmill or bike until you reach a predetermined peak heart rate or until you develop symptoms such as pain or shortness of breath and need to stop. Throughout the test, the doctor monitors your pulse, blood pressure, and your heart’s electrical activity.

What nuclear/PET stress testing shows about your heart’s function

Also known as a radionuclide scan, the nuclear test uses a tracer age which is not a dye, it is a medically safe radiopharmaceutical agent which is injected through an IV into your bloodstream. It highlights the heart and blood flow on a painless, positive emission tomography (PET) scan given following a medicated stress test and to do a comparison, we perform a second PET scan image when your heart is at rest before giving a medicated stress test. This is a very safe way to collect lots of vital information about the health of your heart. Cardiac PET scan is considered the ultimate gold standard non invasive way to gain detailed information about your heart.

At Northwest Houston Heart Center, our cardiac specialists consider the nuclear test the gold standard of stress tests, as the PET scan is incredibly advanced and an accurate diagnostic tool for coronary artery disease — blockages in the heart’s arteries.

Northwest Houston has its own dedicated cardiac PET scanner, one of the few places in the greater Houston area that does, and it’s provided the onsite nuclear test for over 10 years. Dr. Aslam is certified by the Certification Board of Nuclear Cardiology, and the center’s PET scan facility is an Accredited Facility by the Intersocietal Accreditation Commission, making Northwest Houston the place to be for proper cardiac diagnosis and effective treatment.

The cardiac PET scan images reveal:

• Any damaged muscles
• Areas that don’t receive enough blood
• Blocked arteries (coronary artery disease)
• Scarred heart tissue from a previous heart attack
• Risk of sustaining a first or subsequent heart attack

From these results, the doctor develops a detailed, personalized treatment plan for each patient.

If you’re having symptoms of heart disease, or you have an increased risk for it, it’s time to come into Northwest Houston Heart Center for a stress test, diagnosis, and treatment. Give us a call at any of our locations — in Tomball, Cypress, Magnolia, or The Woodlands, Texas — today, or book online. You can also text us at 832-402-9518.