By: Dr. Michael J. Bunda
Cardiologists often order diagnostic tests to better understand the interworking of your heart. Understanding why the test was ordered along with proper test preparation are important to eliminate potential cancellation or rescheduling for patients. Two tests that are often misunderstood are the Echocardiogram (or echo) and the Stress Echocardiogram (commonly called a stress echo or stress test).
An echocardiogram is a detailed static examination of the four chambers of the heart. During the exam, ultrasound waves from a hand-held probe create pictures of the heart’s valves and chambers that allow us to evaluate the beating and pumping of the heart. Doppler can be used during the test to assess blood flow through the heart. Blood flow is often seen as color images flowing through the heart on the monitor.
Patients are commonly referred for an echocardiogram for the following:
A general practitioner may ask you to have an echo regardless of whether the symptom is cardiac in origin because it allows them to rule out certain conditions.
This test does not require an NPO status, which is a medical term for withholding food, fluids, or medication prior to a test. A patient can wear regular clothing and shoes. The test typically takes 1 hour.
After the echocardiogram, if the patient is diagnosed with CHD (coronary heart disease) or if the doctor determines that further examination is needed to make a diagnosis, he or she might recommend a stress echo test.
A stress echo is a more dynamic test that examines the heart in action. It combines an ultrasound of the heart with a stress test. A stress test, often called a treadmill test, measures how your heart works when experiencing added workload or “stress” of exercise.
A stress echo test has 3 phases. First, the patient lies on the exam table and the technician performs an echocardiogram as a baseline reading of the LV (left ventricular) function at rest. Step two the patient undergoes a standard treadmill test, where the speed and grade of the treadmill are increased every three minutes. At each interval, the technician checks the patient for a change in symptoms, usually pain or shortness of breath. The patient remains on the treadmill until they become symptomatic or they reach their target heart rate. Step three, the patient quickly returns to the exam table and receives another echocardiogram for the tech to assess LV function for changes.
The stress echo test might be ordered if coronary artery disease is suspected, or if abnormalities are found during a baseline electrocardiogram or echocardiogram and require further examination.
The exam requires NPO status – patients are asked to refrain from eating or drinking anything but water for 3-4 hours prior to the test. Patients on beta-blockers (a treatment for hypertension and coronary artery disease) are asked to not take their medication the day of the procedure. Beta-blockers often diminish the heart rate response. A person taking this medication will have a slower at rest heart rate, and may have a hard time reaching ideal heart rate during the treadmill portion of the exam. Finally, the patient should wear comfortable clothing and shoes, appropriate for exercise. The stress echo typically takes 90 minutes.
Published June 14, 2019