In pulmonary venous PW Doppler, which wave represents atrial systole?

In pulmonary venous pulsed-wave (PW) Doppler, the wave that represents atrial systole is the A wave. This wave corresponds to the period when the left atrium contracts to push blood into the left ventricle just prior to the closure of the mitral valve. During this phase, the pressure in the left atrium increases, causing blood to flow back toward the pulmonary veins, which is detected by the Doppler technique as an upward deflection called the A wave.

The A wave is significant clinically as it provides information about the function of the left atrium and ventricular filling dynamics. It can be affected by various conditions, such as left ventricular compliance or left atrial enlargement, making it an important parameter in echocardiographic assessments of cardiac function. Understanding this can help clinicians evaluate patients for various cardiac conditions.