Stress echocardiography is a valuable test for evaluation of a person who is suspected of suffering from coronary artery disease (CAD). It has good diagnostic accuracy and prognostic predictability. Also known as stress echo, this test is able to determine how well the heart and its valves are functioning, regardless of person’s gender, symptoms, and previous history of ischemic heart disease.
This test involves exercising on a treadmill or a stationary bicycle while the physician is monitoring patient’s vital signs such as blood pressure and rate and rhythm of the heart. It is a dynamic test which uses ultrasound as well as treadmill. The test also helps to determine whether the muscles of heart get enough blood and oxygen from the coronary vessels.
It is a useful test to know the extent of physical work a person can perform if he is undergoing cardiac rehabilitation. It is a simple test. Let us know the procedure of stress echocardiography.
Preparation For Stress Echocardiogram
Stress echocardiography is widely available and less expensive test. It can be performed in an echocardiography laboratory or even in the office of a cardiologist.
- Patient must not eat or drink three hours before the test.
- Patient should not smoke on the day of stress echo as nicotine can affect the heart rate.
- He must not drink coffee and tea or any other caffeinated beverages on the day of test. This can also affect the heart rate.
- Patient must tell the doctor if he is taking any medicine such as blood pressure medicine, medicine to control blood sugar, etc.
- Wear loose and comfortable clothes as he will have to exercise on the treadmill. He must also wear well fitting shoes.
Procedure For Stress Echocardiography Test
Stress echocardiography is a non invasive test, a combination of stress test and echocardiogram. It can be done in two ways, with exercise and pharmacological method. However, the most common is exercise stress echocardiography. The test is performed in three stages. The first phase is resting phase. The second stage is stress test and the third is stress echocardiography.
Resting phase: This is the first stage of test. In this stage the doctor will perform a resting ECG (electrocardiogram). Patient has to lie down on the examination table. The doctor will place six leads on the chest and 4 leads or patches one on each limb. They are also called electrodes. The electrodes are then connected to electrocardiogram machine. ECG measures electrical activity of the heart such as rate and rhythm of heart. The doctor will also measure the blood pressure.
Once ECG is performed, the next step is to perform echocardiography in resting stage. Patient has to lie on his side on the examination table. Echocardiogram is nothing but ultrasound of the heart. Sound waves are emitted through the probe called transducer over the chest. The waves are than reflected back and the machine interprets them. The physician applies jelly over the skin of chest. He then moves the device called transducer which emits sound waves. Images are created of heart movement, valve, and other internal structures of heart.
Second stage, stress test: In this phase the patient is made to walk and run on treadmill or perform exercise on stationary bicycle for. The intensity of exercise is gradually increased depending on the health of patient. The test usually takes 6 to 10 minutes till patient feels fatigued or heart rate has reached the test limit. During exercise the patient has to inform the doctor if he feels dizzy or has chest pain.
Third stage, stress echocardiography: Soon after the treadmill test, patient returns back to examination table. He lies down on one side. The physician will once again perform echocardiogram test. The transducer is rubbed on the chest. Sound waves emitted from the transducer will be flashed back in the form of images. These images are those in which the heart has worked under stress. The main implication of stress echocardiography is to evaluate the left ventricular function and its abnormality if any induced due to myocardial ischemia. After the test, patient will lie down for few minutes till his blood pressure and heart rate becomes normal. He will be able to walk slowly after this.