Cardiology Fellowship...Stress Lab & Echocardiograms

The next two weeks of my internship were really fun and informative. I shadowed various nurses, techs, and fellows throughout the Echocardiogram and Stress Labs. Some of the interesting things I observed in the echo rotation included a Trans-esophageal Echocardiogram (TEE), Echo Stress tests, and Trans-thoracic Echocardiograms (TTE). For the echo stress test, the patient runs on the treadmill at increasing levels of difficulty until they reach their target or maximum heart rate, and meanwhile are hooked up to ECG leads; once the patient reaches the target heart rate they are rushed to a table where the tech and doctor performs a Trans-thoracic echocardiogram on their heart. The echocardiogram (TTE) takes pictures of the heart from various angles to determine abnormalities of the heart post exercise and compares the function to the rest pictures taken pre-exercise.
The Trans-esophageal Echocardiogram (TEE) test was also intriguing because the doctor would place a long probe down the patient’s esophagus and take pictures of various parts of the heart from different angles. The TEE monitors valve function, and can show if there is an irritation in the muscle tissue. It gives a 3D picture of the inside of the heart and valves. Trans-esophageal Echocardiograms are used before surgeries to check for blood clots and Pulmonary Emboli’s ; if these things existed the procedure may not be able to be performed because it could put the patient at high risk for a complication.
In the stress lab I learned about Exercise Stress tests and the Medicated Stress Tests, which are the two different kinds of stress tests used. The stress tests are very helpful tests used on patients that have previously had a stent implanted in their coronary arteries; they are useful because if the stress test is positive then this could be an indication that the artery is possibly being blocked or that another artery needs a stent. Stress tests can also be used on patients that are experiencing chest pain after surgery. For the exercise stress test, the patient runs on the treadmill at increasing levels of difficulty until they reach their target or maximum heart rate, which is 220 minus the patient’s age. Then they are given a nuclear substance that is pumped through the heart in order for nuclear pictures to be taken of the heart at both rest and during stress or exercise. The medicated stress test is done on patients who cannot walk on the treadmill long enough for their heart rate to reach the target value. For these patients, adenosine or other drugs are injected into the patient to imitate the effect of exercise or stress on the heart, and a nuclear material is also given so that nuclear images can be taken of the heart. The pictures are taken by a nuclear imaging machine that takes images for three to five minutes of all areas of the heart to check that it is beating in the proper fashion; the stress tests also show if there are areas of the heart where the muscles aren’t contracting properly. If the muscles aren’t contracting properly then this could be an indication that a heart attack may have occurred, causing ischemic damage to that area of the heart.

Jennalee Trombley