“An endograft is a stent covered with graft material on the internal or external surface. It can be introduced percutaneously into the aorta at the site of the aneurysm. Once securely anchored at either end of the aneurysm, it replaces that part of the artery so that the blood flowing within it exerts no radial pressure on the weakened section of the artery wall. Relieving the aneurysm of pressure will happen only if the endograft is sufficiently well sealed at either end so that it does not migrate and, importantly, so that blood does not leak into the part of the artery with the weakened wall.”
“More particularly in FIG. 1, flange (26) is shown in a flared condition, which condition may be its relaxed geometry or may be a geometry imparted thereto by flow in the occluded direction. In the case where the flared shape of flange (26) is its relaxed geometry, flange (26) may include an outward bias to that shape, such that when tubular member (10) is deployed into an endolumenal space (not shown in FIG. 1), flange (26) may engage a radially confining endolumenal wall defining that space (not shown) and thereby enhance the reduction of flow around tubular member (10) between outer surface (18) and the endolumenal wall.”
“It is believed that this invention is particularly useful when the seal member is secured to the outer surface of a stent-graft as the tubular member. This variation is particularly useful in the treatment of intravascular aneurysms, wherein the seal member includes leakage flow around the stent-graft and substantially isolates that flow from the dangerous, abnormal aneurysmal wall. It is further believed that the broader aspects of tubular member-seal member combination of the invention has utility in the prevention of leakage flow around the outer surfaces of implantable endolumenal medical devices.”
“The skilled team would have been interested in a general way in anything that might improve the performance of Dr Cribier’s THV, which was part of their common general knowledge. Reducing PVL would be only one of several means of making such an improvement, but it would nonetheless have been in the mind of the skilled team in December 2003. The hypothesis is that the team was given a copy of Thornton and read it with interest. They would have regarded it as having come from a field related to TAVI. They would have been aware that the seals used for endografts treating AAA must be particularly effective because a leak in the endograft is liable to be fatal. The flange in Thornton is clearly shown in figure 1 and discussed as a seal in some detail in the specification. In my view the skilled team would have thought it obvious to try using the Thornton flange as a seal on a THV in the manner described by Dr Buller, with a reasonable expectation of success – by which I mean an expectation of reducing PVL to a significant extent. Had that been done, the excess of fabric towards the unattached end of the seal would have caused it to fold in deployment and consequently to become bunched up according to the construction of that term I have reached above. The blood flow would have caused the fabric to bulge out and lie adjacent to the vessel wall, conforming with its contours, thus preventing blood flow past the THV to a significant extent.”
“I think this was putting the matter too simply. The present case is an example of the frequent circumstance in which there is overlap between the circles of expertise of the members of the skilled team, to use a Venn diagram image. Mr Meade’s point would have been a good one if Professor Lutter had raised a reason why the invention in the 254 Patent would not have been regarded as obvious to a skilled interventional cardiologist and that reason was plainly solely within the latter’s circle of expertise. In my view that did not apply to the present case.”
“sac noun 1 BIOLOGY. A natural baglike cavity in an organism; the membrane or other structure enclosing this. 2 MEDICINE. A pouch formed by the pathological dilation or protrusion of a part; the membranous envelope of a hernia, cyst, tumour, etc.”
“… it seems to me that the skilled person would understand the sac to consist of the cavity and also its walls. Also, it is a sac and therefore must have ends which, at the minimum, are broadly perceptible. So the walls must at least approximately meet at each of the two ends.”
“A sac consists of a cavity created between the fabric of the inner and outer skirt, together with its fabric walls which at least approximately meet at its two ends. The inner fabric may be inside or outside the frame. The outer fabric must be adapted to move freely enough to lie sufficiently closely against the adjacent vessel wall, such as to reduce leakage to a significant extent.”
“I have found that that the invention claimed in the 254 Patent is obvious over Thornton. The important difference between that invention and the one claimed in the 766 Patent is that the latter requires a sac and therefore a cavity with two walls. Nothing in Thornton teaches the further step of creating a sac and nothing in the skilled team’s common general knowledge would have led the team towards using a sac as a seal. The 766 Patent is not obvious over Thornton.”
“Whether sealed or open to the bloodstream via slots, pores or otherwise, the skilled person will nevertheless understand the patentee to be using the word sac in accordance with its ordinary English meaning, referring to a baglike cavity or pouch. In other words, a structure with walls of some description that is substantially (if not wholly) enclosed so that it can fill.”
“It is difficult to envisage how the concept of a flange, as shown in Figure 1 in Thornton, would work well in a TAVI device. A stiff material would not create a seal with an irregular surface, although it may seal against a calcium free, regular section of the aorta. A soft material would not function as a flange: it would not press firmly against the wall of the vessel of the unsecured end, unless squeezed between the wall and the stent, in which case it would not operate as a flange and will not serve a useful function. I cannot therefore see how a flange would work to prevent leakage in an aortic heart valve to any useful extent.”
“… procedural fairness not only to the parties but to the witnesses requires that if their evidence were to be disbelieved they must be given a fair opportunity to deal with the allegation.”
“I do not accept that merely because the suggestion that what he said in his witness statement was untrue (or simply misguided) was not put specifically to him (a proposition that inevitably he would deny) means that I am bound to accept his position. It is, of course, important to be fair to a witness, particularly if serious imputations as to the witness' honesty and integrity are being made, and there may be other areas of a witness' evidence that need to be challenged head-on, but the days of the "I put it to you" cross-examination on other matters have long since gone.”