While measuring jugular venous pressure, 'a' wave is indicative of:
The pressure pulsations that occur in the right atrium are transmitted in retrograde fashion to the large veins near the hea. Atrial contraction produces the first pressure peak called the a wave. The c wave is the transmitted manifestation of the rise in atrial pressure produced by the bulging of the tricuspid valve into the atria during isovolumetric ventricular contraction. The v wave mirrors the rise in atrial pressure before the tricuspid valve opens during diastole. Ref: Barrett K.E., Barman S.M., Boitano S., Brooks H.L. (2012). Chapter 30. The Hea as a Pump. In K.E. Barrett, S.M. Barman, S. Boitano, H.L. Brooks (Eds), Ganong's Review of Medical Physiology, 24e.
Atrial filling
Atrial relaxation
Atrial contraction
Ventricular relaxation