A transthoracic echocardiogram (TTE) is an ultrasound of your heart performed by pressing a handheld probe against your chest. It typically takes 30 to 40 minutes, requires no fasting or special preparation, and uses no radiation. It’s one of the most commonly performed cardiac tests, providing detailed images of your heart’s chambers, valves, and blood flow in real time.
Why a TTE Is Ordered
The most common reason for a TTE is to check how well the left side of your heart is pumping. This comes up frequently when symptoms suggest heart failure, such as shortness of breath, swelling in the legs, or unexplained fatigue. The test measures your ejection fraction, which is the percentage of blood your heart pushes out with each beat. A normal ejection fraction falls between 53% and 73%, with slight variation between men and women.
Beyond pumping strength, a TTE can evaluate heart valve problems like narrowing or leaking, identify the cause of a heart murmur, check for fluid around the heart, look for blood clots or unusual growths inside the chambers, and assess the aorta. It’s also used to screen family members of people with inherited heart conditions like hypertrophic cardiomyopathy, and to monitor connective tissue disorders like Marfan syndrome that can affect heart structures over time.
How to Prepare
There’s essentially nothing you need to do. You can eat, drink, and take your medications normally before the test. When you arrive, you’ll be asked to remove clothing from your upper body and change into a hospital gown. That’s the extent of preparation.
What Happens During the Test
A sonographer (the technician who performs the scan) starts by attaching small sticky patches called electrodes to your chest, and sometimes your legs. These connect to an electrocardiogram (ECG) that tracks your heart rhythm throughout the exam. The ECG helps the sonographer time the ultrasound images to specific moments in your heartbeat.
Next, the sonographer applies a water-based gel to the ultrasound probe, called a transducer. The gel eliminates air gaps between the probe and your skin, which improves image quality. The sonographer then presses the probe firmly against your chest and moves it to different positions, capturing images from multiple angles. You’ll feel pressure, and the gel may be cool, but the test isn’t painful.
During the exam, you may be asked to roll onto your left side, breathe in and hold your breath, or exhale and hold. These instructions help the sonographer get clearer images. Rolling to the left shifts your heart closer to the chest wall. Holding your breath at certain points moves your lungs out of the way, since air blocks ultrasound waves.
The Four Acoustic Windows
The sonographer captures images from four standard positions on your body, each called a “window.” Each window reveals different parts of the heart that would otherwise be hidden behind ribs or lungs.
- Parasternal window: The probe is placed just to the left of the breastbone, in the third or fourth rib space. This is typically the first view obtained and gives a clear look at the heart’s chambers, walls, and valves from the side. You’ll be lying on your left side for this one.
- Apical window: The probe moves down to the fifth rib space near the bottom tip of the heart. This view captures all four chambers at once and is especially useful for measuring how strongly the heart contracts.
- Subcostal window: You lie flat on your back with your knees bent to relax your abdominal muscles. The probe goes just below the ribcage, angled upward toward the heart. This is particularly helpful for patients who are difficult to image from other positions.
- Suprasternal window: The probe is placed in the small notch at the base of your throat while you lie on your back with your neck slightly extended. This window provides a view of the aortic arch, the large blood vessel that curves over the top of the heart.
At each window, the sonographer may tilt and rotate the probe to capture different slices of the heart. A comprehensive exam includes dozens of individual images and video clips from these four positions.
How Doppler Measures Blood Flow
Part of the exam uses a technology called Doppler ultrasound, which measures the speed and direction of blood moving through your heart. It works by detecting tiny shifts in the frequency of sound waves as they bounce off moving red blood cells. Blood flowing toward the probe shows up in red on the screen, while blood flowing away appears in blue.
This is particularly useful for spotting valve problems. A leaking valve shows blood flowing backward through it. A narrowed valve shows blood speeding up as it squeezes through a smaller opening. The sonographer can measure exact flow velocities, which helps determine how severe a valve problem is. Doppler also reveals abnormal pressure differences between heart chambers, a sign of conditions that may not be visible on the structural images alone.
After the Test
Once the sonographer finishes capturing images, the electrodes are removed and you can wipe off any remaining gel. There’s no recovery period. You can drive yourself home and resume all normal activities immediately.
The images are reviewed and interpreted by a cardiologist, who writes a formal report for the doctor who ordered the test. Turnaround time varies by facility, ranging from same-day to several days. The report covers measurements of chamber sizes, wall thickness, valve function, ejection fraction, and any abnormalities detected. If the report doesn’t address the specific question your doctor had in mind, it’s often because the reason for the test wasn’t clearly communicated on the order form, something your referring doctor can follow up on directly with the interpreting cardiologist.