What is a stress echocardiogram?
A Stress Echocardiogram combines a standard Exercise Stress Test with an Echocardiograph (cardiac ultrasound). It is most often used to to determine whether the heart muscles are receiving sufficient blood and oxygen during periods of exercise. The echocardiogram component provides information about the function of the heart, whilst the exercise testing measures the performance and capacity of the heart, lung and blood vessels. In most cases, the test is carried out to assist in the diagnosis of coronary artery disease.
How can I prepare for a stress echocardiogram?
It is strongly recommended that patients neither eat 2 hours prior to the test, nor that they smoke or consume caffeine within this timeframe. Additionally, medicines which are considered to be Beta Blockers should be stopped 48 hours prior to the test. Patients should also wear appropriate clothing and footwear to maximise comfort when using the treadmill.
The procedure consists of three components; the first being a resting echo component, the second being an exercise stress test, and the final one being a stress image taking component. During the first component, three small electrodes and wires will be placed upon the patient's chest in order to monitor heart rate. The patient will be asked to lie on their side, as a transducer with gel will be placed at various positions upon the chest. The transducer is positioned in between ribs and a small amount of pressure is required to obtain high quality images.
During the cardiac exercise stress test component, patients will be required to remove all items of clothing from the waist up; ladies may request a gown or sheet to cover up if necessary. The patient's skin will be prepared for the procedure using some rough paper and alcohol wipes. Once attached to the patient, 12 electrodes will be then connected to the ECG machine in order to measure the heart's electrical activity. During the cardiac exercise stress test, patients will walk on a treadmill until they reach their maximal exercise capacity. Every 3 minutes, the speed, incline and resistance of the treadmill will increase, for a period of up to 15 minutes maximum. During the test, one or more medical professionals will monitor the patient's ECG, heart rate, blood pressure and heart rhythm. The test may be stopped if the patient develops chest pain, the ECG changes, their blood pressure is becoming a concern, or the patient becomes too tired to continue exercising.
Upon completing the exercise stress test component, the patient will resume their position on the bed as quickly as possible so that the final 'stressed images' may be recorded to preserve the patient's maximum heart rate. The patient's heart will be scanned by the cardiologist with the same ultrasound probe as before for a few minutes to obtain these final images. The pre-stress and post-stress images will be compared side by side by the reporting cardiologist.