What does "M-mode echocardiography" primarily assess?

M-mode echocardiography is a specific technique within echocardiography that provides a one-dimensional view of the cardiac structures over time, allowing for precise measurement of chamber dimensions and assessment of wall motion. This technique creates a time-motion graph that captures the motion of the heart's anatomical structures such as the left ventricle, right ventricle, atria, and valves.

By using M-mode, clinicians can obtain critical information regarding the size of heart chambers, thickness of the walls, and functionality, which are essential for diagnosing various cardiac conditions. The measurements obtained can help in evaluating left ventricular function, assessing diastolic dysfunction, and monitoring changes over time in response to treatment or disease progression.

While M-mode does not directly assess blood flow velocity, overall cardiac function in a comprehensive manner, or cardiac rhythm, it is fundamentally aimed at providing detailed visualization and measurement of the heart's anatomical features and their movements, which is why it is focused specifically on chamber dimensions and wall motion over time.