Cardiac ultrasound, commonly called echocardiography, echo or a heart ultrasound, or a cardiovascular ultrasound, provides ultrasound imaging of the heart. Echocardiography uses standard 2D and 3D ultrasound as well as Doppler to create images of the heart.
Ultrasound uses sound waves to create images. Echocardiography can be done using transthoracic echo (TTE) imaging using an ultrasound transducer placed against the chest, or transesophageal echo (TEE) where an ultrasound probe is placed down a patient's throat to image the heart from inside the esophagus.
A cardiac ultrasound may be performed in various ways, depending on the information that the referring doctor needs. A standard ultrasound is called a transthoracic echo. A sonographer will apply gel on to the chest area and then use a transducer over the heart area. The transducer will record the sound wave echoes from the heart which a computer will convert into moving images on a monitor. A small amount of iodine-based contrast medium may be injected intravenously to improve visualization of the heart’s structure.
A transesophageal echocardiogram (TEE) may be indicated if there is difficulty in visualizing the heart on a standard echocardiogram. During this procedure, a flexible tube containing a transducer is guided down the patient’s throat and into the oesophagus.
Doppler ultrasound may also be utilized. When Doppler sound waves bounce off blood cells moving through the heart and blood vessels, they change pitch. These changes allow the doctor to measure the speed and direction of blood in the patient’s heart. Doppler techniques are used in conjunction with standard and TEE to check blood flow and pressure in the arteries of the heart.
A stress echocardiogram may also be included as some heart conditions only occur during physical activity. During this procedure, ultrasound images of the heart are taken before exercise (walking on a treadmill), and then again when the patient is at rest, and a comparison is made.
Echo contrast exams are performed using a micro-bubble agent that is injected through an IV line placed in the patient. The ultrasound waves reflect off the bubbles to enhance, highlight the blood. This can aid in evaluation of patients where traditional imaging is not clear for various reasons.
Point of care (POC) ultrasound is seeing increasing use for quick cardiac evaluations. Small, hand-held ultrasound systems are increasing being used for imaging assessments of the heart, rather than relying only on heart sounds on a stethoscope, because the causes of various heart sound anomalies can be seen on the ultrasound for a more accurate diagnosis.
A cardiac ultrasound is a non-invasive treatment, done on an outpatient basis. The procedure allows for determination of heart size, visualization of damaged heart valves, high blood pressure and thickening in the walls of the heart muscle, as well as many heart defects.
Read about advances in cardiac ultrasound:
Recent Advances in Echocardiography Technology
Links to Echocardiography Educational Videos
Advances in Ultrasound Systems
Top Echocardiography News and Video From ASE 2017
A Glimpse Into the Future of Cardiac Ultrasound