Cardiology Coding Alert

What it is: Cardiologists perform cardiovascular stress testing, a noninvasive diagnostic test, for patients with coronary risk factors, a history of coronary artery disease (CAD), or symptoms that may indicate CAD. Physicians use these tests to:

• diagnose coronary disease

• evaluate existing disease to determine if change has occurred

• evaluate the risk of an adverse coronary event.

Keep in mind: Typically, the physician will first perform an evaluation of the patient that includes history and physical (H&P) and a resting electrocardiogram (ECG). This evaluation aids in the selection of exercise or pharmacologic stresses and helps determine the need for stress imaging, such as an echo or radionuclide study.

What happens: Usually, the patient will undergo stress testing on a treadmill or a stationary bicycle. A technician takes blood pressure and heart rate when the patient is at rest and during exercise. During exercise, the heart and body respond to the stress of increased physical activity. A diseased heart responds abnormally to stress -- which can be evaluated by monitoring the patient's blood pressure, heart rate and ECG. The cardiologist makes a diagnosis based on the results.

If the patient undergoes a pharmacological stress test, the circumstances change. Adrenergic stress agents, such as dobutamine, stimulate the heart, increasing the heart rate, oxygen demands of the heart, and coronary blood flow.

Note: Dobutamine stress testing is contraindicated for early post-myocardial infarction patients. In these patients, the heart is too sensitive for standard treadmill exercise. In these cases, cardiologists use drugs, such as adenosine and Persantine, that act as vasodilators to dilate the coronary arteries directly, rather than flogging the heart to increase blood flow.