Page "Circulatory system" Paragraph 43

In 1025, The Canon of Medicine by the Persian physician, Avicenna, " erroneously accepted the Greek notion regarding the existence of a hole in the ventricular septum by which the blood traveled between the ventricles.

" Despite this, Avicenna " correctly wrote on the cardiac cycles and valvular function ", and " had a vision of blood circulation " in his Treatise on Pulse.

While also refining Galen's erroneous theory of the pulse, Avicenna provided the first correct explanation of pulsation: " Every beat of the pulse comprises two movements and two pauses.

Thus, expansion: pause: contraction: pause.

[...] The pulse is a movement in the heart and arteries ... which takes the form of alternate expansion and contraction.