During a standard echocardiogram, a technician called a sonographer presses a small handheld device against your chest and moves it around to capture real-time images of your heart using sound waves. The whole process typically takes about an hour, requires no needles or radiation, and you can go home right after. There are a few different types of echocardiograms, though, and the experience varies depending on which one your doctor orders.
How a Standard Echocardiogram Works
The most common type is called a transthoracic echocardiogram, or TTE. It works the same way a pregnancy ultrasound does, just aimed at your heart instead. The device (called a transducer) sends high-frequency sound waves into your chest. When those waves hit different structures, like heart muscle, valve tissue, and flowing blood, they bounce back at slightly different speeds and strengths. The machine measures how long each echo takes to return and how much the signal changed, then uses that data to build a moving picture of your heart on a screen.
The sound waves used in cardiac imaging range from 2 to 12 MHz. Higher frequencies produce sharper images but don’t penetrate as deep, so the sonographer may adjust the frequency during the exam depending on what they need to see. Because sound travels poorly through air and very well through soft tissue and blood (at about 1,540 meters per second), the gel applied to your chest eliminates any air gap between the transducer and your skin.
What Happens Step by Step
You’ll lie down on an exam table, usually on your left side for part of the test. A technician attaches small sticky patches called electrodes to several spots on your chest. These track your heart rate and rhythm throughout the exam, giving the sonographer a live reference as they capture images.
Next, the sonographer applies a clear gel to your chest and presses the transducer against your skin. They’ll move it to several positions between and below your ribs, angling it to get different views of your heart’s chambers, valves, and major blood vessels. You may be asked to hold still, shift your position, or breathe in a specific way to improve the image quality. Some views require you to hold your breath briefly so your lungs don’t block the sound waves.
The test is painless, though the pressure from the transducer can feel slightly uncomfortable at times, especially when it’s pressed firmly between your ribs. Once the sonographer has captured all the images they need, they wipe off the gel and remove the electrodes. There’s no recovery time, and you can eat, drink, and go about your day normally.
What the Test Measures
An echocardiogram captures a surprising amount of information. One of the most important numbers is your ejection fraction, which tells you what percentage of blood your heart pumps out with each beat. A normal ejection fraction falls between 50% and 70%. Below 40% generally signals heart failure with reduced pumping ability, while values between 40% and 49% are considered mildly reduced. An ejection fraction above 75% is rare and can itself indicate a problem.
Beyond ejection fraction, the test measures the size of each heart chamber, the thickness of the heart walls, and how well each valve opens and closes. The sonographer can detect blood flowing backward through a leaky valve, spot areas of the heart wall that aren’t contracting properly, and identify fluid buildup around the heart. All of this happens in real time, so the images show your heart actively beating rather than capturing a single frozen moment.
Stress Echocardiograms
A stress echocardiogram adds a physical challenge to the standard test. The sonographer first takes a resting set of images, then you exercise on a treadmill or stationary bike. You start slowly, and the intensity increases gradually until you reach your target heart rate or develop symptoms. Immediately after you stop exercising, the sonographer captures a second set of images and compares them to the resting ones. The goal is to see whether parts of your heart muscle struggle when it’s working hard, which can reveal blockages in the coronary arteries that don’t show up at rest.
If you can’t exercise, a medication can be given through an IV to make your heart beat faster and harder, mimicking the effect of physical activity. Either way, the test requires some preparation. You may need to skip certain medications beforehand, avoid heavy meals, and wear comfortable clothing you can move in. Your doctor’s office will give you specific instructions, including whether to fast or adjust any prescriptions.
Transesophageal Echocardiograms
Sometimes the standard chest-wall approach doesn’t provide clear enough images. The ribs and lungs sit between the transducer and the heart, and in some people this creates too much interference. A transesophageal echocardiogram (TEE) solves this by placing the ultrasound probe inside your esophagus, which runs directly behind the heart with no bone or air in the way.
This version is more involved. You’ll need to fast for eight hours beforehand and remove any dentures. During the procedure, your throat is numbed with a spray or gel, and you receive sedation through an IV to keep you relaxed. While you’re sedated, a provider guides a thin, flexible tube with a tiny transducer on its tip down your throat and into your esophagus. The images are dramatically clearer than a standard echo, which makes TEE especially useful for examining heart valves in detail or looking for blood clots inside the heart.
Afterward, your throat will stay numb for about an hour. You shouldn’t eat or drink until that numbness wears off completely, since swallowing won’t work normally and you could choke. A sore throat lasting two to three days is common, and some people notice a weak or scratchy voice temporarily. Rarely, the tube can scrape the inside of the throat. Because of the sedation, you’ll need someone to drive you home.
Bubble Studies and Contrast
In some cases, a small amount of contrast material is added to the echocardiogram to improve the picture. One common version is the bubble study, where a technician rapidly shakes a syringe of saline mixed with a tiny amount of air to create microbubbles, then injects them into a vein in your arm. On the ultrasound screen, these bubbles light up brightly as they flow through the right side of your heart. If bubbles cross over to the left side, it suggests there’s an abnormal opening between the heart’s chambers, such as a patent foramen ovale (a small hole that never fully closed after birth). You may be asked to bear down or cough during the injection to briefly increase pressure on the right side and make any crossing easier to detect.
A different type of contrast uses commercially manufactured microspheres injected through an IV. These are used when the standard images aren’t sharp enough to measure chamber size or pumping function accurately. The contrast helps define the edges of the heart chambers on screen, making measurements more reliable. Mild side effects like headaches, backaches, or rashes can occasionally occur, though severe reactions are very rare.
Getting Your Results
The sonographer captures the images, but they don’t interpret them during your appointment. A cardiologist reviews all the recordings and measurements, typically within 24 hours of the test. Most people receive their results from their ordering provider within three days. The report will include your ejection fraction, chamber sizes, valve function, and any abnormalities detected. If something significant shows up, your doctor may want to discuss next steps or order additional testing to get a more complete picture.