A stress echocardiogram also called a stress echo is a test that is a combination of the echocardiogram and a treadmill or bike exercise test. It could also be done by giving the patient to be tested medication that imitates the effect of exercise on the heart. It uses the technique of ultrasound imaging to evaluate the motion of the heart when it reacts to stress. The stress echocardiogram does not involve any surgical procedure and is carried out by a cardiologist and a sonographer. The treadmill test determines the heart’s reaction to physical stress while the echocardiogram will examine the working of the heart when the patient is on the exercising machine. This combined test evaluates the status of the heart when it is resting and also during and immediately after stress providing the doctor with necessary details related to whether there are blocks in the coronary arteries and also the state of the valves of the heart.
Common Uses of a Stress Echocardiogram
It is a test that is commonly used by cardiologists to see how well the muscles of the heart pump blood into the body. The main purpose of the stress echocardiogram is to discover if there is any decrease in the flow of blood to the heart. It is also performed to see whether the heart muscles are receiving enough blood flow and thereby oxygen when it is being worked under stress. It can also be used to check angina that is becoming worse, when the patient has recently suffered a heart attack. The echocardiogram can also be used to obtain specific details regarding valvular disease and pressure in the lungs and the heart.
Usually the patient is advised not to eat or drink anything for at least three hours before the stress echocardiogram test is taken. The patient is expected to wear loose fitting clothes and comfortable walking shoes. Wet stick patches called electrodes will be place at various places on the chest, arms and legs and wires will be connected to them in order to record the activity of the heart. A blood pressure cuff will be fixed on the arm which will inflate every now and then. Any medication usually taken can be had with water, unless otherwise specified by the doctor.
The equipments used for the stress echocardiogram will be the treadmill or a stationery bike and an ultrasound machine that consists of a transducer preferably with 2D resolution. Digital imaging is imperative for a stress echocardiogram in order to compare thunder stress functions of the heart at rest.
How Does the Procedure Work?
The procedure utilizes high frequency sound waves (ultrasound) that will afford a moving image of the heart. The sound waves are sent through the body using the transducer which resembles a micro phone. These sound waves bounce off from the heart and are sent back to the transducer as echoes which are changed into images on a monitor that looks like a computer or TV screen. The images of the heart that are produced can be single, two or three dimensional.
How is the Procedure Performed?
The stress echo is performed in three stages; the resting echocardiogram, the stress test and a repetition of the echocardiogram soon after the exercise when the heart is still beating very fast. The whole stress echocardiogram takes about 40 to 60 minutes though the patient will be using the treadmill or stationery bike for about ten minutes. Before the patient starts exercising on the treadmill or bike, the sonographer or the ultrasound technologist will take images of your heart at rest. The patient is then asked to walk on the treadmill or use the stationery bike, where the procedure is similar to a normal stress test. The incline on the electrical treadmill can be adjusted and gradually the incline and the speed are increased in such a way that the patient is walking up a hill. More or less immediately after the patient has stopped utilizing the treadmill, he is asked to shift to the examination table and asked to lie on his left side. Once again the echocardiogram is done again whilst the rate of the heart beat is still high. The patient may be asked to hold his breath or breathe in or out so that the images obtained will be clear.
Through out the exercising process the patient’s blood pressure is being checked intermittently. The patient will be monitored continuously till the heart beat rate and blood pressure has got back to their pre-exercise stage.
Experience During and After the Procedure
The patient does not experience any adverse effects after having taken the Stress Echocardiography test. During the treadmill exercise session there are possibilities of the patient encountering fatigue, but usually there are no untoward experiences during or later the procedure. During the procedure it is quite normal to feel a low pressure and sometimes vibrations from the transducer, but it is not painful.
Benefits and Risks
The benefits of the stress echocardiogram are that it is a non-invasive form of testing the results of which can help the doctor determine how well a heart is functioning and whether the treatment meted out to the patient has been effective or not. It helps doctors diagnose coronary artery disease and also see if the size of the heart too big. Risks for this non-invasive form of testing is extremely low or practically nil. Rare complications can include unusual heart rhythms, collapse or a heart attack.
The stress echocardiogram may not offer accurate results if the patient is obese or has chronic obstructive pulmonary disease like emphysema, severe asthma or chronic bronchitis.