Theventricularseptumseparatestherightandleftventriclesandthusispartofbothventricles.Itisdirectedobliquelybackwardtotheright,andcurvedwiththeconvexitytowardtherightventricle;itmustbeemphasizedthatthetotalcardiacseptumhasacomplex,longitudinaltwistanddoesnotlieinanysingleplane.Itsupperandposteriorpart,isthinandfibrous,andistermedthemembranousventricularseptum.Thegreaterportionoftheseptumisthickandmuscularandconstitutesthemuscularventricularseptum.Theventricularseptumconsistsoftwolayers,athinlayerontheRVsideandathickerlayerontheLVside[1].Themajorseptalarteriestendtorunbetweenthesetwolayers.
