Cardiac Stress Test
The cardiac stress test is also known as the exercise stress test. It is valuable and well-avaiable outpatient examination in cardiology, which can give a lot of information about the ability of the heart muscle to endure physical exercise.
The principle is basically simple, but it brings certain physical demands on the examined patient. The patient must perform a physical activity, during which he or she is monitored by electrodes attached to a machine that records ECG and pulse rate. The physical activity usually includes walking on a treadmill or riding an ergometer (a bike without wheels). The load is slowly increased as the examiner tries to achieve a certain heart rate. We are interested, if the physical strain causes occurrence of symptoms (chest pain, shortness of breath), or any pathological changes in ECG record (arrhythmias, characteristic ischemic changes). If such changes appear, we end the test and evaluate it as positive.
The patient does not need any special preparation. However, it is advisable to take along sporting clothes and comfortable shoes. Fasting is not absolutely necessary, but it is not advised to undergo the testing on a full stomach.
The cardiac stress test can be valuable in patients with suspected angina pectoris, who have no other objective finding (ECG and cardiac enzymes are normal). The angina pectoris and other forms of ischemic heart disease tend to worsen during physical exercise when the heart needs more oxygen. In addition, cardiac stress test may also be performed in young and healthy individuals whose jobs include excessively high physical load (professional sportsmen, firefighters, etc.). The cardiac stress test can confirm occurrence of periodic dangerous arrhythmias that could suddenly threaten life of a previously seemingly completely healthy individual.
The examination has certain physical demands on the patient. When the patient is less mobile, obese or in overall poor physical condition, they may be unable to reach the desired heart rate by physical exercise. In rare cases, the load of the procedure may cause a bout of angina pectoris, heart attack or malignant arrhythmia with sudden death (very, very rarely).
The test is completely non-invasive and it depends only on the patient's physical activity. The results are valuable and help us to confirm (or rule out) connection between the symptoms and physical load. When the diagnosis of angina pectoris is likely, we may administer proper medications and perform other investigations such as the coronary angiography.