New Angina Workup

Patients with risk factors for coronary artery disease -including type 2 diabetes mellitus, hypertension, and a family history of myocardial infarction in a first-degree relative- who develop new symptoms such as angina or exertional dyspnea should be evaluated for obstructive coronary disease. The primary method for this assessment is a stress test.

Two Main Types of Stress Tests

Exercise Stress Test

An exercise stress test involves having the patient walk or run on a treadmill while connected to an EKG monitor. This allows for the assessment of any coronary artery blockages that become apparent during physical exertion. For this test to be effective, patients need to be physically capable of exercising on a treadmill at the required intensity.

Pharmacological (Chemical) Stress Test

When patients cannot complete an exercise stress test, perhaps due to severe shortness of breath, arthritis, or other physical limitations, a pharmacological stress test offers an alternative approach.

During this procedure, patients will receive a coronary vasodilator medication such as adenosine, and nuclear imaging is used to evaluate blood flow (myocardial perfusion) to the heart muscle. Here's how it works:

• In patients without coronary blockages: The adenosine infusion causes blood vessels to dilate, increasing blood flow throughout the heart, which appears normal on imaging.
• In patients with obstructive coronary disease: The coronary arteries are already near their maximum dilation due to the blockage, so adenosine produces little to no improvement in blood flow. This difference is visible on the nuclear imaging and helps identify areas of the heart that aren't receiving an adequate blood supply.

Additionally, this scan would allow for the identification of reversible and non-reversible perfusion defects.