The dicrotic notch on the aortic pressure curve is caused by
The dicrotic notch, a small oscillation on the falling phase of the pulse wave caused by vibrations set up when the aortic valve snaps shut, is visible if the pressure wave is recorded but is not palpable at the wrist. The pulmonary artery pressure curve also has a dicrotic notch produced by the closure of the pulmonary valves.
Closure of the mitral valve.
Closure of the tricuspid valve.
Closure of the aortic valve.
Closure of the pulmonary valve.