Which cardiac assessment method analyzes sound waves to visualize the heart's structure and function?

Echocardiography is the method that uses sound waves to visualize the heart's structure and function. This technique employs high-frequency sound waves (ultrasound) that are transmitted to the heart and then reflected back to create real-time images. These images provide critical information about the heart's chambers, valves, and overall blood flow. Echocardiography is non-invasive and can help in diagnosing various cardiac conditions, assessing heart size and function, and guiding treatment decisions.

In contrast, Doppler ultrasound is a specific technique often used within echocardiography to measure the speed and direction of blood flow, rather than a standalone method to visualize heart structures. The electroencephalogram (EEG) records electrical activity of the brain and is unrelated to cardiac assessments. The electrocardiogram (ECG) measures electrical impulses of the heart to assess heart rhythm and detect issues like arrhythmias, but does not provide images of heart structure or detailed functional analysis like echocardiography does. Thus, echocardiography is the correct answer as it combines both visualization and functional assessment of the heart using sound waves.