Cardiovascular imaging allows physicians at GHS to diagnose cardiovascular disease and evaluate cardiovascular anatomy and function noninvasively. GHS cardiovascular imaging physicians have trained at leading institutions and use the newest technologies to diagnose heart disease. We employ the following imaging techniques to diagnose cardiovascular disease and to aid our cardiovascular surgeons and interventional cardiologists during procedures.
An echo is an ultrasound of the heart. We look at your heart in different views. We look at the walls of the heart, the four heart chambers, the four heart valves, and the blood flow through the heart. We measure the thickness of the walls of the heart, measure the size of the heart chambers, and measure the velocity of blood flow through the heart valves. This test gives us a good idea of your heart function.
This test is a noninvasive test. It takes approximately 30 to 45 minutes to perform. You can eat and take your regular medicines.
A Transesophageal Echocardiogram, or TEE Echo, allows your doctor to record images of your heart from inside your esophagus (the tube that leads from your throat to your stomach.)
This test incorporates ultrasound images into a stress test. We take a set of resting images of your heart. Then we have you walk on the treadmill and when your heart rate reaches its peak at stress, we stop the treadmill and take another set of images. We then compare the two sets of images to see how well the heart squeezes. This gives us an idea if there is a potential for your heart to have blockages in the coronary arteries.
If you are unable to walk on a treadmill due to physician limitations, a medication is given to stimulate your heart and make it think you are on a treadmill.
Steps for the procedure
- Wear comfortable clothes and shoes to walk on the treadmill i.e. tennis shoes.
- Withhold Beta blockers, i.e. Toprol XL for 48 hours.
- You can have a light breakfast or lunch 2 hours before procedure.
- If this is a Dobutamine stress echo, do not eat before the procedure, unless you are a diabetic; then follow your normal diabetic diet.
This is a noninvasive test. It takes approximately an hour to perform.
Nuclear Stress Test
A nuclear stress test is approximately a four hour procedure that will ultimately allow a cardiologist to evaluate the blood flow patterns to the heart.
Upon arrival, the patient will have IV access started in either the hand or arm. A small dose of Cardiolite, a radioactive tracer, will be injected. There are no side effects to the Cardiolite. The patient will then wait for about an hour in the waiting room while eating crackers and drinking water.
Next resting images of the heart will be obtained. The patient will lie flat on their back with their arms above their head for approximately 15-20 minutes. A nuclear medicine gamma camera will slowly rotate around the chest to acquire images during this time.
The stress portion of the procedure occurs next. A patient will either walk on a treadmill or have a medication injected to stress the heart. For the treadmill, a patient will walk until a target heart rate is achieved. The treadmill starts out at a low incline and slow speed; then every three minutes speed and inclined are increased until the target heartrate is attained. A second dose of the Cardiolite will be injected in order to obtain a second set of images. If a patient is having a chemical stress test, a medicaition to dilate the blood vessels of the heart will be injected followed by a second dose of the Cardiolite. The stress medication can have a few side effects – flushing, nausea, headache, or vomiting. If side effects do occur, they normally resolve in just a few minutes. After the stress portion, the patient will be asked to wait a second time in the waiting while eating and drinking.
Finally, stress images will be acquired in the same manner as the resting images usually taking 15-20 minutes again.
Treadmill Stress Test
An exercise stress test measures the function of the heart during exertion. This test specifically shows the changes in the electrical system of the heart during exercise. The changes seen on during exercise provide information about the heart that may not show up on a resting EKG.
When the patient arrives, he or she will have electrodes placed on the chest and hooked up to an EKG machine. A resting EKG will be taken as well as a blood pressure reading. Next, the patient will start walking slowly on the treadmill at a low incline and speed. Every three minutes, the speed and incline will be increased gradually until the patient has reached the target heart rate. Staff will be monitoring heart rate response, blood pressure response, EKG, and any patient symptoms throughout the test.