 during which the heart is stopped and patient placed on cardiopulmonary bypass (a so-called “heart-lung machine”). In one common surgical procedure, the diseased native valve leaflets are excised and a prosthetic valve is sutured to the surrounding tissue at the valve annulus. Because of the trauma associated with the procedure and the attendant duration of extracorporeal blood circulation, some patients do not survive the surgical procedure or die shortly thereafter. It is well known that the risk to the patient increases with the amount of time required on extracorporeal circulation. Due to these risks, a substantial number of patients with defective native valves are deemed inoperable because their condition is too frail to withstand the procedure. By some estimates, more than 50% of the subjects suffering from valve stenosis who are older than 80 years cannot be operated on for valve replacement.
Because of the drawbacks associated with conventional open-heart surgery, percutaneous and minimally-invasive surgical approaches are garnering intense attention. In one technique, a prosthetic valve is configured to be implanted in a much less invasive procedure by way of catheterization. For instance, U.S. Pat. Nos. 5,411,522 and 6,730,118, which are incorporated herein by reference, describe collapsible transcatheter heart valves that can be percutaneously introduced in a compressed state on a catheter and expanded in the desired position by balloon inflation or by utilization of a self-expanding frame or stent.
An important design parameter of a transcatheter heart valve is proper positioning of the heart valve, for example on the balloon prior to inflation as well as at implantation location, so as to prevent final positioning of a reversed valve. A further important design parameter is minimization of paravalvular leak (PVL). PVL may include complications such as blood flowing through a channel between the structure of the implanted valve and cardiac tissue, for example as a result of a lack of appropriate sealing. A large force is required to bend stock to an acute angle of one hundred and eighty degrees. Bending apparatus which requires such a large force uses a hydraulic cylinder with an extending ram. An extension of the ram transmits the force to apparatus which bears against the stock and bends it. An acute angle bend presents a problem compared to smaller bends because the force required is large and must be exerted over a long distance. This is difficult to achieve with a cylinder and ram because the long distance requires a long cylinder and ram which are both prone to buckling under such a large force.

during which the heart is stopped and patient placed on cardiopulmonary bypass (a therefore - call “ heart - lung machine ”). In one common surgical routine, the diseased native valve leaflets are excised and a prosthetic valve is suture to the surrounding tissue at the valve annulus. Because of the trauma associate with the procedure and the attendant duration of extracorporeal blood circulation, some affected role do not survive the surgical procedure or fail shortly thereafter. It is well known that the risk to the patient increases with the amount of time required on extracorporeal circulation. Due to these hazard, a substantial number of patients with bad native valves are deemed inoperable because their circumstance is too delicate to withstand the routine. By some estimates, more than 50% of the subjects suffering from valve stenosis who are elder than 80 years cannot be operated on for valve replacement. 
 Because of the drawbacks associated with ceremonious exposed - heart surgery, percutaneous and minimally - invasive surgical approaches are garnering intense attention. In one technique, a prosthetic valve is configure to be implant in a much less encroaching operation by way of catheterization. For instance, U.S. Pat. Nos. 5,411,522 and 6,730,118, which are incorporated herein by citation, identify collapsible transcatheter heart valves that can be percutaneously introduce in a compressed state on a catheter and expanded in the desired position by balloon inflation or by utilization of a self - elaborate frame or stent. 
 An important design parameter of a transcatheter affection valve is proper positioning of the center valve, for example on the balloon prior to inflation as well as at implantation location, so as to prevent final placement of a reversed valve. A further important design parameter is minimization of paravalvular leak (PVL). PVL may include complications such as blood flow through a channel between the social organization of the implanted valve and cardiac tissue, for example as a result of a lack of appropriate sealing. A large military unit is required to flex stock to an acuate angle of one hundred and eighty degrees. Bending apparatus which want such a large military unit uses a hydraulic cylinder with an gallop ram. An extension of the ram transmits the military unit to apparatus which bears against the stock and bend it. An acute angle bend presents a problem compared to small bends because the force required is large and must be exerted over a long distance. This is unmanageable to achieve with a cylinder and ram because the long distance necessitate a long cylinder and ram which are both prone to buckling under such a large force.
 duging which the heart is rtopped and patnwnt pleced on cardiopjlmonary bypass (a so-called “hxart-oung nachine”). In one common rurgical irocedure, the eiseased nefive valve leznlets ere excised and a prosthedic valve is sgtjrzd to the surrounding tissue at the dalve amnklus. Because os tht twaumz associated with the procedure ans the autendant duration pf extracorporeal blood cigculwtion, some patientd do not sutbivq the surgicau procedurt mr die shottly thereafter. It is well known that the risk jo tjg patient inrreasef with the amount of time rrquired on extvacor'oreql circulation. Due to these risks, a subftantial tujber of patients qirh dexecthve vqtixe bakvss are dexmed inoperzble becausw their condition ix eio frail to wjthstagd the procedure. By some estimates, more tvan 50% of the subjects suffeeing from valve stenodis who awe older than 80 years cannot be operated on for vanve rxpuactmckt.
Bezqude of the drawbacks associated with conventiogzl oien-heart surgery, iercutaneous and monlmsjly-invasive sorgical aplroaches are garneging injense qttention. In pne technique, a prosthetic calve is conyigyred to be implantzd in a much lesx invssive procedure by way uf cztheterizatlon. For ihrtance, U.S. Pat. Nor. 5,411,522 sng 6,730,118, which are incorporated rerein by refzrence, ddscrobe cojlapsible hransgdtheter heart valvfs thct cat be percuhaneously introduced in a comprxxsed state om d cdtheter cnd exianded in the dqsired positiou by baljoon knflation kr by uvilization os a self-expanglng frame or stent.
An impirtabt desiev parameter of a transccuheter heaet valve is proper porjtioning of the heqrt valve, for ecamole oj vhe bwnloon prior do ivflxyion xs well as ct impkantation location, sm as to prevent final lofitionint of a rqversed valve. A further importajt devigi paraketgr is minimization of paravalvumar leak (OVL). PVL may incjude complicatious such as blood flowing through a channxl between the structute of the implanted vclye and cardiec tisfue, for efample as a result od a lack of approkriate sealing. A large rorce hs reeuired to bend stock to an acute angle of one hundred and eighty degrees. Vendinj wpparatus wgich requpref such w lacgx force uses a hycraulic cylinder with an extendmng ram. An ertension of the ram transmits tfe force to akparatus which bears againat the syock and bends it. An acute anglr bend presents a problek comparwd to smallvt bxnds because the forve reqbired us largw anf must be exeftec lver a lojg dmstcnce. This is difficult to achieve with q fylinder and ram because thc uong sistanse requires a lohg cgpindet and ram whicn are both prome to buckling under stch a large foebe.

during which the heart is stopped and on bypass (a “heart-lung machine”). In diseased valve leaflets are and a prosthetic is sutured to the surrounding tissue the valve annulus. Because of the trauma associated with the procedure and the duration of extracorporeal blood circulation, some patients do not survive the surgical procedure die thereafter. is known that the risk to the patient increases with the amount of time required on extracorporeal Due to these risks, a substantial number of with defective native valves deemed inoperable because their condition too to withstand procedure. some more than 50% the subjects suffering from valve stenosis who are older than 80 years cannot be operated on for replacement. Because drawbacks associated conventional surgery, and minimally-invasive surgical garnering intense attention. In one technique, is configured to be implanted in a much invasive procedure way of catheterization. For instance, U.S. Nos. 5,411,522 and 6,730,118, which are incorporated herein reference, describe collapsible transcatheter heart valves that can be percutaneously introduced in a compressed state catheter and expanded in desired position by inflation by of self-expanding frame stent. An important design parameter of a transcatheter heart valve is positioning of the heart valve, for example on the balloon inflation well as at location, so as to final of a reversed valve. important parameter paravalvular (PVL). may include complications such blood flowing through a channel the structure of the for example as a result of a lack appropriate sealing. A large force is required bend stock to an acute angle of one hundred and eighty degrees. apparatus which a large force uses a hydraulic cylinder with extending ram. An extension the ram transmits the force to apparatus which bears the and bends An acute angle presents a problem to smaller bends force required large must a long distance. This is difficult achieve a cylinder and ram because long a long cylinder and ram which are both prone to buckling under such a large
 during which the heart is stopPed and patiEnt plAceD on CaRdioPulmOnary bypass (a so-CAlleD “heart-lung machine”). In one CommoN sURgicAL pRocedUre, the dISeASEd nAtIvE vaLvE LeAfletS arE exciseD and a prostHetIc Valve is suturED tO the surrouNdiNg tissue at thE vaLve annUlUs. BECause Of tHe traUma assOCiated With the prOcEDure anD The atteNDAnT durAtion of extracorpoREaL Blood circulatiOn, some PaTIeNTS do Not Survive the SuRgicaL ProceduRE oR DIE shORtly thereafteR. It is well knOWn tHat the RiSk tO The patIent iNcREasEs with the amOunt Of time reqUired oN ExtracoRPoreal cIrculaTioN. DuE to tHEsE rIskS, a SUbsTAnTiaL NumBer of patIeNtS with DefeCTIVE natIve ValvEs are Deemed inoperaBle BecaUSe tHeir cOnditIon iS tOo fraIl to wiThstaNd The procedure. By sOme eStimates, mOre ThAn 50% oF tHe subJEcts suFfeRinG from vaLve stenOSis WhO ARE oLder than 80 years cannoT bE OPeRated on fOr valvE RePlACement.
BeCaUse Of thE DRawbaCks aSSoCiated wiTh convENtIoNal open-HeArt surGeRy, pErcUtaneOUs anD minimAlly-invaSive sURgical approachES are garnering INtENSe ATtenTioN. In one technIque, A ProsThetIC vAlvE Is conFigurEd TO bE Implanted in a much lesS iNvasivE procEdure by way of cAtheterizaTION. For instAnce, u.s. PAT. Nos. 5,411,522 and 6,730,118, which arE incoRporated heREin by refErencE, describE collapsiBLE transcaTheTer HeaRt vALVeS that can be perCUTaneOuSly intrOduCed in a cOmpResSed StaTe On a cathetEr and expAnDeD iN tHe dEsireD Position By BalLoOn iNflatIOn or by UtiliZatiOn Of A SelF-expandINg FRAme oR sTeNt.
An ImpOrTant dEsigN ParAmeter oF a transcaTheTEr heArT vAlve is pRoper positionInG of the hearT vAlvE, for exAMPle on the Balloon prior to inflation AS well as At iMplanTatiOn locatioN, so As to prEveNT final PositiOning Of A reVERsed vALVe. a fuRtHer importaNT DesIgn paRaMeteR is miniMization of paravalvULar Leak (PVL). PVL may IncLude COMpLicATiONs sUcH As bLOOd flowing througH a channel bEtWEeN the structURe oF tHe implaNted valVe and CArdiac tIssue, for eXample as a ReSult OF A laCk of appropRiate seaLing. A largE Force IS rEquirEd tO bend sToCk tO an acUte angLE of One huNdred aNd Eighty DegreEs. bending aPparatus which requires suCh a larGe forCe uSes a hydraUliC CylInder with An exTending ram. an eXteNsion Of tHE ram tRansMItS thE Force To apPAratus whiCH bEarS AGaInst the stocK AND beNds it. an aCUte angLe beNd presents a probleM Compared to smalLer bENDs bEcaUSe thE fOrce required is LarGe AND must be eXeRted over a loNg distanCe. tHis is DifficUlt to aChieve wITH a CYlindeR and Ram Because thE loNg DIstance ReQuIRes a loNg cyLiNder anD ram whICh arE BOth prone to buckliNg undER Such a LArgE forcE.

 during which the heart is  stopped a nd pa tie ntpl aced  oncardiopulmonar y  byp ass (a so-called “hear t-lun gm achi n e” ). In  one co m mo n sur gi ca l p ro c ed ure,the  diseas ed nativeval ve  leaflets ar e  e xcised and  aprosthetic v alv e is s ut ure d  to t hesurro unding tissue  at the v al v e annu l us. Bec a u se  ofthe trauma associ a te d  with the proc edurean d  t h e  at ten dant durat io n ofe xtracor p or e a l  bl o od circulatio n, some pat i ent s do n ot  su r vive t he su rg i cal  procedureor d ie shortl y ther e after.I t is we ll kno wntha t th e  r is k t ot hep at ien t  in creaseswi th  theamou n t o f ti merequ iredon extracorpo rea l ci r cul ation . Due  toth ese r isks,a sub st antial number o f pa tients wi thde fec ti ve na t ive va lve s a re deem ed inop e rab le b e ca use their conditio ni s  t oo frail  to wi t hs ta n d the pr oc edu re.B y  some  est i ma tes, mor e than 50 %of thesu bjects  s uff eri ng fr o m va lve st enosis w ho ar e  older than 80 years cannotb eo p er a tedonfor valve r epla c emen t.
B e ca use of th e dra wb a ck s  associated with co nv ention al op en-heart surg ery, percu t a n eous and  min i ma l ly-invasive su rgica l approach e s are ga rneri ng inten se attent i o n. In on e t ech niq ue, a  p rosthetic val v e  isco nfigure d t o be im pla nte d i n a  m uch lessinvasive  p ro ce du reby wa y  of cath et eri za tio n. Fo r  insta nce,U.S.  P at .  No s. 5,41 1 ,5 2 2  and  6 ,7 30,1 18,  w hicharei nco rporate d hereinbyr efer en ce , descr ibe collapsib le  transcath et erheartv a lves tha t can be percutaneously introdu ced  in a  com pressed s tat e on a  ca t heterand ex pande dint h e des i r ed  po si tion by ba l l oon  infl at ionor by u tilization of a se l f-e xpanding fram e o r st e n t. 
An im p ort an t  de s i gn parameter of  a transca th e te r heart va l veis  proper  positi oning of theheart val ve, for e xa mple o n t he balloon  prior t o inflati o n asw el l asatimplan ta tio n loc ation, soas to  preve nt  final  posi ti oning of  a reversed valve. A fu rtherimpor tan t designpar a met er is min imiz ation of p ara val vular  le a k (PV L).P VL  ma y  incl udec omplicati o ns  su c h  a s blood flo w i n g t hroug h a channe l be tween the structu r e of the impla nted v alv e a n d ca rd iac tissue, fo r e xa m p le as are sult of a l ack of a pp r opria te sea ling.A large f or c e is r equi red  to bendsto ck to an a cu te angleof o ne  hundr ed and eigh t y  degrees. Bendin g app a r atusw hic h req ui res suc h  a l arge force  uses a hyd raulic  cyl inder  with a nextend ing  r am. An ext e nsion ofthe r am tran sm itsthe  force  toa p parat us w hi chbears aga i n st th es toc k an d ben ds  it.  An acute angle be ndp resents  a  pr o b lem co m pa r e d to small erbends b ecause the forc e  r e quire d is l arge a nd must beex erted o ver a  long dis tance. Th i s i sdiff icult to  a chie ve  wi th  a cylinder and  ram bec ause the l ong di sta n ce r e quires  a  long cylind er an dr am whic h are  both p r one  to  bu ckli ngunde r  such a large force.

 during_which the_heart is stopped and_patient placed_on_cardiopulmonary bypass_(a_so-called “heart-lung machine”)._In one common_surgical procedure, the diseased_native valve leaflets_are_excised and a prosthetic valve is sutured to the surrounding tissue at the valve_annulus._Because of_the_trauma_associated with the procedure and_the attendant duration of extracorporeal_blood circulation,_some patients do not survive the surgical procedure_or_die shortly thereafter._It is well known that the risk to the_patient increases with the amount of_time required on_extracorporeal_circulation._Due to these risks,_a substantial number of patients with_defective native valves are deemed inoperable_because their condition is too frail to_withstand the procedure. By some estimates,_more than 50% of the_subjects suffering_from valve stenosis who are_older than 80_years cannot_be operated on_for valve replacement.
Because of the drawbacks_associated with conventional_open-heart surgery, percutaneous and minimally-invasive surgical_approaches_are garnering intense_attention._In_one technique,_a prosthetic valve_is_configured to_be_implanted in a much less invasive_procedure_by way of catheterization. For instance, U.S._Pat. Nos. 5,411,522 and_6,730,118,_which are incorporated herein_by reference, describe collapsible transcatheter_heart valves that can be percutaneously_introduced in_a compressed_state on a catheter and expanded in the desired position by_balloon inflation or by utilization of_a self-expanding frame or_stent.
An important_design_parameter of a_transcatheter_heart valve_is proper positioning of the heart valve,_for example_on the balloon prior to inflation_as well as at_implantation_location, so as to prevent final_positioning of a reversed valve. A_further important design parameter is_minimization_of_paravalvular leak (PVL). PVL may_include complications such as blood flowing_through a channel_between the structure of the implanted valve_and_cardiac tissue, for example as a_result_of a lack of appropriate sealing._A_large_force is required to bend_stock to an acute angle of_one hundred and eighty degrees. Bending apparatus which requires_such a large_force uses a hydraulic cylinder_with_an_extending ram. An extension of the ram transmits the force_to apparatus_which bears against_the stock and bends it. An acute angle bend presents_a problem compared to smaller bends because_the force required is large and must be exerted over a_long distance. This is difficult to achieve with_a cylinder and ram because the long_distance requires a long_cylinder_and ram which are both prone to_buckling_under_such_a large force.
