House Calls runs every two weeks. Today’s column is written by Randy Landenberger, a registered diagnostic cardiac sonographer at Sutter Coast Hospital.
I think there’s an echo in here, an echo in here, an echo in here…
An echocardiogram, that is. The first thing I’ll say about this test is that the name is confusing because “echocardiogram” sounds so much like electrocardiogram (EKG or ECG). Specifically an echo is an ultrasound exam of the heart, and is also known as an echogram or a cardiac ultrasound. Many patients tell me they’ve had echos on their gallbladder, their neck, or their legs. What they really mean is that they’ve had ultrasound exams on those areas. Echo refers specifically to the heart.
The ultrasound allows us to look through the muscle walls and directly inside of the heart to assess the condition of the muscle and the four valves, the size of the chambers, and the blood flow within the heart to identify murmurs. This is all done in “real time,” meaning that we’re watching it live as it happens. However it does not directly see the coronary arteries and blockages within those arteries. Indirectly we can see the effects of arterial blockages, previous heart attacks (myocardial infarctions — or dead tissue), or heart attacks that are in progress.
“Doppler” ultrasound is also part of the exam. A “color” window is laid over the grayscale image of tissue to show us which direction the blood is flowing. This is typically done over valves to help reveal if there is any narrowing or leakage. We can then measure that blood flow to further evaluate the condition. Valves are most often the cause of “murmurs.” The color can also reveal holes in the heart tissue — another common cause of murmurs and these can be a major contributor in strokes or TIA’s.
There are many types of heart disease. First off, there’s the kind you were born with, congenital, and the kind you acquire due to age or lifestyle. Congenital heart conditions can take myriad forms, from holes to malformed valves, chambers and vessels. Acquired heart disease includes ischemia (lack of blood and oxygen to the heart muscle due to blockage in the coronary arteries), valves that are clogged and narrowed (stenotic), or leaking (regurgitation or insufficiency), tissue that has died and/or scarred, thickening of the heart muscle from hypertension (atherosclerosis or peripheral artery disease) or hereditary — a condition called hypertrophy. There are a variety of “cardiomyopathies” or heart “muscle” diseases that may have been acquired from general infections, septic conditions, drug or alcohol abuse, or just a bad draw of luck (idiopathic, or unknown source).
Typically an exam lasts about 30 minutes from the time the tech first puts the probe to your chest. The time to initially interview the patient and put all information into the ultrasound machine, and the time to close it all out and create a report, can extend the time to an hour. Usually patient are lying on their left side. When the exam is done in the Echo Lab, a special bed with a hinged drop section under the chest allows the tech to move and manipulate the probe under the patient to obtain the best images. A support behind the patient makes it much more comfortable to be in that position for a long period.
The quality of these studies varies widely. Some patients have what we call a “glass chest,” meaning we can see all the structures clearly. Many patients are less than clear, but we can still obtain the information needed by the physician to make a diagnosis and the proper treatment. The challenge for the echocardiographer is that the heart is surrounded by your ribs and lungs and the limitations of ultrasound are that it does not penetrate through bones or lungs. The image produced by ultrasound is a two-dimensional slice on the monitor screen. Yes, there is 3-D imaging — but that’s another story and not practical for everyday exams.
To overcome these obstacles, we obtain images from three different angles. For the first set, the probe is placed to the left of the sternum, about midway up the chest wall. The second set of images are taken from near the bottom of your ribs on your left side. The third set of images are taken from just below the sternum, at the top of your abdomen.
Some patients are sensitive to touch, or have conditions which make the positioning uncomfortable, or are unable to lie still for an extended period of time. Conversely, many patients fall asleep during the exam.
If you’re a patient scheduled to have an echo and you experience back problems or neuropathies, ask your physician about pain relievers or anxiety medications before your appointment.
Here at Sutter Coast, I make the room and experience as comfortable as possible. The room is warm, the lights are low, and I have a great selection of music to transport you to dreamland for half an hour. For some patients it’s like an echo spa, and others prefer the rock ’n’ roll emporium, or sono-country.
Of course nearly every patient wants to know the results. “What did you see?” “Any problems?” “Am I okay, will I live?” Sorry, but the tech can’t discuss the results. The exam has been digitally recorded for a qualified physician to “read,” or interpret. That physician will send the report to your doctor who ordered the test.