Stress tests measure electrical (EKG/ECG) changes to your heart during stress and exercise. The results of the test help your doctor diagnose coronary artery disease (CAD).
Using stress tests, a cardiologist can evaluate how your heart responds when it’s being pushed. Most often, a patient will walk on a treadmill or pedal on a stationary bike as the doctor or trained provider carefully monitors your symptoms and assesses how your heart reacts to the stress. This exercise helps to detect any chest pain, shortness of breath, abnormal rhythms and palpitations, and provides insight into the health of your heart valves and blood flow.
Stress tests also help your doctor know the kind and level of exercise that will be appropriate for you, so you can work together on developing a care plan and a game plan for a routine exercise regime.
Other stress tests include the following:
Nuclear Stress Test
A nuclear stress test measures blood flow to your heart muscle at rest and during stress/exercise. It is performed similar to a regular stress test but provides images in addition to electrocardiograms. Nuclear pictures of the heart are taken before and after exercising. During a nuclear stress test, a very low level of radioactive substance is injected into your bloodstream. This substance mixes with your blood and travels to your heart. A special scanner, which detects the radioactive material in your heart, creates images of your heart muscle. Inadequate blood flow to any part of your heart will show up as a light spot on the images, because not as much of the radioactive substance is getting there. This may indicate a blockage in the arteries of your heart.
Persantine or Adenosine Cardiolite
For patients that are unable to walk on the treadmill, an intravenous medication (persantine or adenosine) can be given. This replaces the need for walking on the treadmill and still allows the stress test to be performed.
Cardioversion is a brief procedure where an electrical shock is delivered to the heart to convert an abnormal heart rhythm back to a normal rhythm. Most elective or "non-emergency" cardioversions are performed to treat atrial fibrillation, also known as atrial flutter, a benign heart rhythm disturbance originating in the upper chambers (atria) of the heart.
External cardioversion is performed with a defibrillator, either in an emergency situation or as a scheduled treatment for arrhythmia. Internal cardioversion is delivered by a device similar to a pacemaker, called an implantable cardioverter defibrillator (ICD). ICDs are used to treat arrhythmias in the lower heart chamber (ventricle) such as ventricular tachyarrhythmia or fibrillation. These arrhythmias can cause sudden cardiac death (SCD) because of the dangerously fast heart rate.
Tilt Table Study
The tilt table study is used to evaluate patients who have had syncope (loss of consciousness). It is an extremely simple study, and in most cases is quite safe. In a tilt table study, the patient is strapped to a table, which is then mechanically tilted to an upright position. While monitoring the pulse, blood pressure, electrocardiogram, and sometimes blood oxygen saturation, the patient is left in a "motionless standing position" for 20 to 30 minutes. When the patient's syncope is reproduced during the test, a "positive" tilt table study is said to have occurred.