... circumferential wall stress σc = Fc/S Division of the axial force Fa by the area S of the cube face it pulls at yields the axial wall stress σa = Fa/ S Division of the radial force Fr by the area S of the ... retaining axial force provided by the myocardial tissues surrounding the artery distally of the cross section x = In the following, we mainly consider the effect of these four forces in the wall cross ... by the deformation of the myocardium in the region of the bridge are, moreover, also negligible, then axial wall stress remains constant, irrespectively of the actual wall thickness of the segment...