Cardiovascular Exercise Testing
Cardiovascular exercise testing is an investigation used to assess cardiac function. It may reveal the existence of coronary heart disease, unapparent on an electrocardiogram (ECG) at rest. During exercise the need for oxygen of the myocardium (heart muscle) is increased. If there is a narrowing of the coronary arteries (heart vessels) during exercise the increased need of oxygen can cause symptoms and ECG changes, to suggest the existence of coronary heart disease.
It is recommended that parents should be dressed and wearing shoes comfortable as going to submit a moderate exercise. The test starts by measuring heart rate and blood pressure. It is also performed a resting electrocardiogram. Then, it is applied on the body six to twelve electrodes that are connected to an EKG and a computer that monitors and records the electrical activity of the heart. The tested will be pedaling on a bike similar to a normal one, following a specific protocol, which involves increasing the resistance to pedaling steps, each step of 30 W with duration of 3 minutes. Commonly used 3 steps or reaching a maximum heart rate. At the end of each level of effort is measured the heart rate, blood pressure and is registered an ECG. The entire exercise test lasts between 15 and 30 minutes.
The test is stopped when the patient experiences chest pain, difficulty in breathing, palpitations (arrhythmias), dizziness or EKG shows significant changes when registering for coronary heart disease. Also, the test can be stopped when the tested cannot resist raising any effort, despite the lack of symptoms or ECG changes suggestive. Test interpretation takes into account several criteria: clinical, electrocardiographic, and hemodynamic. The results of the exercise testing, the cardiologist can determine a diagnosis and make recommendations about treatment and other necessary investigations (angiography, etc.).
Patient Preparation: Tell your doctor if:
- take any medicines, including those for erectile dysfunction;
- you are allergic to any medicines, including anesthetics;
- you are taking anticoagulants or clotting problems;
- have joint problems and you cannot exercise;
- Are pregnant.
Contraindications: Exercise testing is not indicated in severe heart or other organs (for example lung disease), severe uncontrolled hypertension, anemia, acute infections, etc. Exercise testing it is not useful when resting on the electrocardiogram occur changes which do not allow the interpretation of the test (for instance in left bundle branch block) or when the patient cannot make effort (peripheral arterial disease, arthritis, etc.).
Exercise testing can have a number of cardiac or non-cardiac complications, rare in practice. Analysis of a large number of tests showed a mortality of 0.5 per 10,000 tests. Cardiac complications encountered with a frequency of 2.3 to 4.8 % are represented, in descending order, by: hypotension, acute heart failure, heart rhythm rare (especially when the cause is ischemic heart disease) and ventricular tachyarrhythmias, acute coronary syndromes. Any of these complications is an indication to stop the test immediately and establishing the appropriate treatment, including electric defibrillation or other resuscitation maneuvers.
It is recommended not to bathe or hot shower at least one hour after the test.