`Niazi
`
`USOO6638268B2
`(10) Patent No.:
`US 6,638,268 B2
`(45) Date of Patent:
`Oct. 28, 2003
`
`2Y- - 2
`
`I Cal. . . . . . . . . . . . . . . . . . . . . .
`
`7/1998 Bednarek ..................... 606/41
`5,785,706 A
`5,807,249 A 9/1998 Oin et al. ................... 600/374
`5,824,031 A * 10/1998 Cookston et al. ........... 607/122
`5.2. A : 3.19. i. o:
`5,916,214. A
`6/1999 Cosio et al. .................. 606/41
`6,001,085 A 12/1999 Lurie et al. ................. 604/282
`6,002.955 A 12/1999 Willems et al.............. 600/374
`6,006,137 A * 12/1999 Williams .................... 607/119
`6,022,341 A
`2/2000 Lentz ......................... 604/523
`6,080,151 A 6/2000 Swartz et al. ....
`... 606/45
`6,090,084 A 7/2000 Hassett et al. .............. 606/281
`6,093,173 A * 7/2000 Balceta et al. .............. 604/164
`6,122,552 A
`9/2000 Tockman et al. ........... 607/116
`6,179,809 B1 * 1/2001 Khairkhahan et al. ... 604/95.01
`6.228,052 B1 * 5/2001 Pohndorf .....
`... 604/96.01
`6,273,881 B1 * 8/2001 Kiemenei .................. 604/532
`2002/0103474 A1
`8/2002 Voda .......................... 604/530
`* cited by examiner
`Primary Examiner Ira S. Lazarus
`Assistant Examiner Tu Cam Nguyen
`(74) Attorney, Agent, or Firm-Philip G. Meyers
`(57)
`ABSTRACT
`A double catheter includes an outer, resilient catheter having
`shape memory and a hook-shaped distal end, an inner,
`pliable catheter slidably disposed in the outer catheter and of
`greater length than the outer catheter So that a distal end
`portion of the inner catheter can be extended or retracted
`from a distal end opening of the outer catheter to vary the
`overall length of the double catheter, the inner catheter
`preferably having an internal lumen Suitable for the intro
`duction of contrast media, and a mechanism operable from
`the proximal end of the outer catheter for changing the
`curvature of the hook shaped distal end of the outer catheter.
`Such a catheter of the invention can cannulate the coronary
`Sinus without significant manipulation.
`
`27 Claims, 5 Drawing Sheets
`
`(54) CATHETER TO CANNULATE THE
`CORONARY SNUS
`
`(76) Inventor: Imran K. Niazi, 9080 Upper River Rd.,
`River Hills, WI (US) 53217
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 150 days.
`
`- - -
`(*) Notice:
`
`(21) Appl. No.: 09/828,502
`(22) Filed:
`Apr. 6, 2001
`O
`O
`(65)
`Prior Publication Data
`
`US 2001/0052345 A1 Dec. 20, 2001
`Related U.S. Application Data
`Apr. 7
`6O) Provisional
`lication No. 60/195701 filed
`(60) systona application No. 60/195,701, filed on Apr. 7,
`7
`(51) Int. Cl." ............................................. A61M 25/098
`(52) U.S. Cl. ....................... 604/528; 604/528; 604/523;
`604/530; 604/16401; 604/264; 604/96.01
`(58) Field of Search ................................. 604/528, 523,
`604/164.01, 530, 264, 266, 96.01, 93.01,
`95.01
`
`(56)
`
`References Cited
`U.S. PATENT DOCUMENTS
`4,790,831 A : 12/1988 Skrikiski .................... 604/282
`4,886,506 A * 12/1989 Lovgren et al.
`... 604/280
`5,290,229 A
`3/1994 Paskar ......................... 604/95
`5,336,182 A * 8/1994 L
`2- - - 2
`undquist et al. ............ 604/95
`5,505,698 A
`4/1996 Booth et al. ......
`... 604/96
`5584803 A 12/1996 Stevens et al. ................ 604/4
`5,643,231 A 7/1997 Lurie et al. .......
`... 604/282
`5,690,611 A 11/1997 Swartz et al. ................. 604/53
`5,782,741 A 7/1998 Bradshaw et al. ............. 600/3
`
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`1
`CATHETER TO CANNULATE THE
`CORONARY SNUS
`
`This application claims priority of U.S. Provisional
`Application No. 60/195,701, filed Apr. 7, 2000.
`FIELD OF THE INVENTION
`This invention relates to medical devices, particularly to
`catheters of the type used to cannulate the coronary Sinus.
`BACKGROUND OF THE INVENTION
`The coronary Sinus is a venous Structure that is three to
`four centimeters in length and one centimeter in diameter. It
`forms a part of the venous drainage of the heart. The
`coronary Sinus arises from the posterior inferior aspect of the
`right atrium and courses over the posterior Surface of the
`heart, ending in the great cardiac vein. It is the final common
`venous drainage of most of the heart.
`Cannulation of the coronary sinus has until recently not
`been considered important from a medical viewpoint. Medi
`cal researchers have cannulated the coronary Sinus in ani
`mals and in humans to obtain information about the func
`tioning of the heart. Cardiac Surgeons will, during cardiac
`Surgery, cannulate the coronary Sinus for retrograde car
`dioplegia. However, routine cannulation of the coronary
`Sinus is not performed when there is no therapeutic advan
`tage to performing coronary sinus angiography.
`It has recently become apparent that the coronary sinus
`and its branches can be used to place catheters (fine pacing
`catheters) on the epicardium of the left ventricle. The left
`Ventricle can then be paced via these catheters. Preliminary
`Studies show that pacing the left ventricle produces signifi
`cant benefit in patients with heart failure, especially those
`with conduction disturbances. Therefore, Studies are under
`way to Study the coronary Sinus anatomy and place the
`pacing catheters in the appropriate branch of the coronary
`Sinus. Unlike for coronary arterial circulation, which has
`been well Studied because of its therapeutic benefit, there are
`no presently available preformed catheters that will Slip
`easily into the coronary sinus. U.S. Pat. No. 5,423,772
`exemplifies one proposed device designed for use in the
`coronary Sinus wherein the catheter has a double curve.
`Congestive heart failure is one of the commonest diag
`noses leading to hospital admission in the United States.
`There are 2 to 5 million patients diagnosed with CHF in the
`U.S. annually, and 15 million worldwide. Treatment of heart
`failure consists of medications, and cardiac transplantation
`in Severe cases. Other forms of Surgery, e.g. Valve Surgery,
`are also Sometimes helpful. Attention has recently focused
`on resynchronization therapy. About 30-50% of people with
`severe CHF have asynchronous contraction of the cardiac
`chambers. This can be corrected by pacing the right atrium,
`the right ventricle and the left ventricle at optimal intervals
`to provide Synchrony. Leads to pace the right atrium and
`right ventricle have been used for years. Recently, leads have
`been devised to pace the left ventricle by passing the lead
`through the coronary Sinus into a branch vein that overlies
`the left ventricle. Delivery systems to guide the leads into
`the appropriate branch veins are now being researched.
`Currently available catheters and catheter Systems have
`several disadvantages which render lead delivery difficult.
`For example, the anatomy of the right atrium and the
`coronary Sinus origin is different in patients with congestive
`heart failure than in patients with normal sized hearts. These
`differences in part form the basis for the design of the
`delivery system of the present invention. Such differences
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`include that the OS of the coronary Sinus lies higher in the
`right atrium in Such perSons than in normal perSons. The
`euStachian ridge is unusually prominent, and the right atrium
`is usually larger than normal. Subeustachian fossae are more
`well developed in the large right atria. There is great
`variation in the size of the coronary sinus and its shape and
`direction, and the target coronary branch veins arise at acute
`angles from the main coronary Sinus in many patients. This
`renders it difficult to pass a lead into these branches. Venous
`Valves obstruct the passage of the lead. These are variably
`placed, frequently close to the origin of the coronary veins.
`The present invention provides a catheter especially adapted
`for use in the coronary Sinus, especially in patients Suffering
`from congestive heart failure.
`SUMMARY OF THE INVENTION
`A double catheter according to one aspect of the invention
`includes an outer, resilient catheter having shape memory
`and a hook-shaped distal end configured for cannulation of
`the coronary Sinus, an inner, pliable catheter Slidably dis
`posed in the outer catheter and of greater length than the
`outer catheter So that a distal end portion of the inner
`catheter can be extended or retracted from a distal end
`opening of the outer catheter to vary the overall length of the
`double catheter, the inner catheter preferably having an
`internal lumen Suitable for the introduction of a fluid, Such
`as contrast media, into the coronary Sinus and also for
`passage of a pacing lead, and a mechanism operable from
`the proximal end of the outer catheter for changing the
`curvature of the hook shaped distal end of the outer catheter.
`Such a catheter of the invention can cannulate the coronary
`Sinus without Significant manipulation, enable an angiogram
`of the coronary sinus by means of an occlusive balloon
`which includes the proximal coronary Sinus at the time of
`contrast media injection, Serve as a conduit for the passage
`of a fine coronary sinus pacing lead (5 French in diameter),
`provide backup Support for introducing this lead over a
`guide wire into the distal branches, and minimize the Steps
`necessary for the placement of a coronary sinus lead, thereby
`allowing rapid introduction of Such a lead.
`The invention further provides a method of using a
`catheter to place a pacing lead in a transverse branch of the
`coronary Sinus in order to treat a related condition Such as
`congestive heart failure. Such a method for placing an
`electrical lead in a lateral branch of a coronary sinus vein
`using a double catheter includes the Steps of inserting the
`catheter into the coronary Sinus, advancing a guide wire
`through the catheter into a coronary Sinus lateral branch
`vein, advancing the inner catheter out of a front end opening
`of the outer catheter along the guide wire into the branch
`vein, inserting the lead through the outer and inner catheters
`to a target location in the branch vein, and withdrawing the
`catheter leaving the lead in the branch vein. If necessary, the
`curvature of the double catheter can be adjusted in order to
`enter the coronary Sinus. These and other aspects of the
`invention are discussed in the detailed description that
`follows.
`BRIEF DESCRIPTION OF THE DRAWING
`In the accompanying drawing, wherein like numeral
`denote like elements:
`FIG. 1 is a side view of a double catheter of the invention;
`FIG. 2 is a side view of the outer catheter of FIG. 1;
`FIG. 3 is a side view a second embodiment of a catheter
`according to the invention;
`FIGS. 4 and 5 are diagrams illustrating preferred shapes
`for the outer guide and obturator of FIG. 3;
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`FIG. 6 is a diagram illustrating an alternative inner
`catheter for use in the embodiment of FIG. 3; and
`FIGS. 7 and 8 are diagrams illustrating use of the catheter
`of FIG. 3 a method of introducing a pacing lead according
`to the invention.
`
`DESCRIPTION OF PREFERRED
`EMBODIMENTS
`FIGS. 1 and 2 illustrate a double catheter 10 according to
`the invention having a typical length of 60 cm. An outer
`catheter 11 is made of a braided Silastic or Similar material
`to allow torque control and Stiffness. An inner catheter 12,
`which slides in and out of outer catheter 11, is constructed
`of a more pliable, Soft material Such as Silicone. The
`combination of outer and inner catheters 11, 12 provides a
`number of advantages, including variability in the reach of
`the catheter, and outer catheter Stiffness necessary for
`manipulation along with inner catheter Softness, which
`permits Safe cannulation of the coronary Sinus and advance
`ment of catheter 11 into the distal coronary sinus for
`purposes of Support. It also allows the inner catheter 12 to
`conform to the torturous course of a coronary Sinus.
`Inner catheter 12 fits into lumen 15 of outer catheter 11,
`and is preferably coated with a hydrophilic lubricious mate
`rial which allows catheter 12 to slide in and out of outer
`catheter 11 with ease. A proximal end 13 of inner catheter 12
`terminates in a hemoStatic valve 14 having an adjustable
`diaphragm. Valve 14 prevents leakage of blood when a 5
`French pacing lead is introduced through inner catheter 12
`into the coronary system. Preferably, a distal end 16 of inner
`catheter 12 has a tip 17, for example, about 1 cm long, made
`of a material Softer than the remainder of inner catheter 12.
`This may, for example, be accomplished by making tip 17
`thinner than the remainder of catheter 12, or by making a
`bilayered inner catheter 12 wherein the one layer extends
`further than the other to form the tip and optionally is made
`of a material softer than that of the other layer.
`Outer catheter 11 has several functions. Because of its
`StiffneSS and torque, it can be manipulated in the right atrium
`to allow cannulation of the coronary Sinus. Such StiffneSS
`also lends Support to the pacing lead as it is introduced into
`the distal coronary sinus. A distal end 18 of outer catheter 11
`has an external inflatable cuff or balloon 21. Balloon 21 can
`be inflated with air by means of a Syringe 22 connected to
`balloon 21 as described below. Inflation of balloon 21 allows
`occlusion of the proximal coronary sinus, which is necessary
`for obtaining a coronary Sinus angiogram.
`The proximal end of outer catheter 11 has several features.
`A port 26 including a shutoff valve 30 is provided for
`introduction of air into balloon 21. This port 26 is connected
`by means of a passage 27 in the wall of catheter 11 with the
`distal balloon 21. A torque coupling 28 of a type known in
`the art may be tightened down on inner catheter 12 to
`prevent it from moving within Outer catheter 11. A torque
`Screw 29 is attached to a cable or wire 31 that runs in the
`wall of outer catheter 11 and may be wound over one or
`more small rounded corners or small pulleys 35 set in the
`wall of catheter 11. This cable 31 is anchored, as by
`embedding a enlarged end thereof, at a point 34 close to a tip
`32 of outer catheter 11. Rotation of torque screw 29 causes
`cable 31 to be retracted, which changes the shape of the
`outer catheter 11 (making the hooked shape more pro
`nounced as shown by the arrow) and counter-rotation does
`the opposite. Torque Screw 29 may, for example, comprise
`a Spool or reel having an external circumferential groove on
`which cable 31 is attached and is wound or unwound as
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`needed. A port 36 with an associated shutoff valve 37 is
`provided through the wall of outer catheter 11 for delivering
`a saline flush through lumen 15.
`For optimum deployment in the coronary Sinus, inner and
`outer catheters 11, 12 preferably have a predetermined shape
`and a certain degree of StiffieSS to maintain Such shape
`during manipulation in the heart, but Still flexible enough to
`bend when required. As shown in FIG. 2, the hook-shaped
`distal end of Outer catheter 11 may comprise Substantially
`Straight Segments spanning three bends 41, 42 and 43. First
`bend 41 adjoining a Straight, proximal portion 44 of outer
`catheter 11 is in the range of about 130 to 180, especially
`130 to 175. Second, intermediate bend 42 extends in a
`direction opposite bend 41 and is in the range of about 75
`to 100. Third bend 43 near the distal end of outer catheter
`11 extends in the same direction as bend 42 and is in the
`range of about 130 to 175. These ranges refer to the angle
`formed by the Straight Segments adjacent each bend when
`the catheter is in an undistorted State. Operation of the
`deflection device to tighten the cable will reduce these
`angles, especially for Second bend 42. The material of which
`outer catheter 11 is made, e.g. Silastic, has Sufficient shape
`memory to return to its original shape when undistorted. The
`undistorted Shape of outer catheter 11 can be varied and
`catheter 10 thereby made in Several sizes to accommodate
`different heart sizes. For example, for a normal size atria
`with a prominent Eustachian Valve, outer catheter 11 may be
`substantially J-shaped with no first bend (bend 41=180°),
`whereas for large atria with a prominent Eustachian Valve, it
`may be useful to make catheter 11 more in a question mark
`shape (shown inverted in FIGS. 1-2).
`Coronary sinus catheter 10 may be deployed in the
`following fashion. Distal balloon 21 is deflated, inner cath
`eter 12 is withdrawn completely into outer catheter 11, and
`catheter 10 is inserted through a venous sheath introduced in
`the left XX Subclavian vein. It is guided into the right atrium
`over a guide wire, and the guide wire and sheath are then
`removed. Catheter 10 is rotated until tip 17 lies within the
`tricuspid valve, then advanced until tip 17 is seen to lie in the
`inferior-most portion of the tricuspid valve. If the reach of
`catheter 10 in this configuration is not Sufficient to cannulate
`the tricuspid valve, then inner catheter 12 is advanced out of
`outer catheter 11 to make the entire System longer.
`Subsequent manipulation is carried out in a left anterior
`fluoroscopic view. Counterclockwise torque is exerted on
`catheter 10. At the same time, inner catheter 12 is gradually
`withdrawn. Eventually, catheter 10 slips over the tricuspid
`annulus and, because of the counterclockwise torque, twists
`and pops into the proximal coronary sinus. In Some
`instances, it may come to lie at the mouth of the proximal
`coronary sinus. In that case, inner catheter 12 is gradually
`advanced until the coronary sinus is cannulated. Once the
`coronary Sinus is cannulated, inner catheter 12 is advanced
`as far as it will go into the coronary Sinus and/or great
`cardiac vein. Distal balloon 21 on outer catheter 11 is
`inflated using Syringe 22 to occlude the proximal coronary
`Sinus. Contrast medium is injected via a port 25 through the
`lumen of inner catheter 12 to obtain a coronary sinus
`angiogram. Port 36 is then hooked up to a Saline flush. A
`coronary Sinus lead is introduced through a hemostasis valve
`14 into inner catheter 12. It is positioned using a guide wire
`in an appropriate branch of the coronary Sinus.
`A triple catheter 50 according to the invention is designed
`to overcome the obstacles described above that are encoun
`tered with congestive heart failure patients and further
`provide a more economical catheter System that does not
`rely on Specialized miniature adjustment mechanisms. The
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`System includes an outer guide catheter 51, an inner guide
`catheter 52 nested therein, an obturator 53 nested inside the
`inner guide 52. In one example, outer guiding catheter 51 is
`2.9 mm in outer diameter, 2.6 mm inner diameter. It is
`relatively Stiff and has a braided design, which lends Support
`and one-for-one torque control. In this respect, it can
`resemble an angioplasty guiding catheter. The shape of outer
`guiding catheter 51 is similar, but not identical, to a left
`amplatz curve. The proximal end terminates in an Screw
`adjusted hemostatic valve 56, to allow introduction of leads
`or wires of different diameters without leakage of blood.
`There is also a side-port 58, preferably with a 3-way valve,
`to allow injection of contrast medium and Saline.
`Inner guiding catheter 52 made of a Soft, pliable material
`Such as Silicone, and in this example is 2.6 mm in outer
`diameter and 2.3 mm in inner diameter. It has no longitu
`dinal braiding, which makes it extremely flexible and able to
`conform to various shapes. Inner catheter 52 is designed to
`advance over a guide wire into a side branch of the coronary
`sinus, in conjunction with the obturator 53. Its flexibility
`allows it to negotiate tortuous vessels and Side branches that
`originate from the coronary Sinus at an acute angle, yet it still
`possesses the radial Strength needed to prevent it from
`collapsing when obturator 53 is withdrawn. Inner guide 52
`is longer than outer guide 51, e.g., 68 cm in length. The
`proximal end of guide 52 has a hemostasis valve 57 to
`prevent back bleeding and a side port 59 to permit contrast
`medium injection.
`Obturator 53 is preferably made of very pliable silicone,
`and has a central lumen that will accommodate an 0.038 inch
`guide wire. Obturator 53 fits into inner guide 52, and in one
`embodiment is 70 mm long, 2.1 mm in outer diameter
`tapering to 1.25 mm diameter at its tip. In use, obturator 53
`tracks over a 0.038" guide wire 81 into a targeted side branch
`56, in concert with the inner guide catheter 52. A tapered tip
`71 of obturator 53 may protrude from the front end opening
`of inner catheter 52. Without such a protruding tip 71, the
`edge of inner catheter 52 might catch on venous valves or
`sharp angles. The terminal 7 mm of obturator 53 may have
`a bend 72 therein of up to about 30 degrees, i.e., defining an
`angle from 150-180 degrees. This allows tip 71 to function
`as a guiding device for the 0.038" guide wire 81, which can
`then be directed into acutely angled Side branches. The
`proximal end of obturator 53 terminates in a standard port 60
`allowing attachment of a 10 cc Syringe.
`Referring to FIGS. 7 and 8, outer guiding catheter 51 is
`initially connected to a Syringe and pressure monitoring
`system and then inserted into the right atrium 80. The
`physician attempts to use it to cannulate the coronary Sinus
`without the use of the other components. If this Succeeds, an
`0.038" hydrophillic-coated guide wire 81 is advanced
`through it, and used to cannulate the target lateral coronary
`sinus side-branch 56. (If the side branch 56 cannot be easily
`cannulated, the angled obturator 53 can be extended and
`used to direct the guide wire 81 as illustrated in FIG. 7.) The
`inner guide 52, with obturator 53 inside, is then passed
`through outer guide 52 over the 0.038" wire into the target
`side branch 56. Obturator 53 is then withdrawn, and an
`electrical lead 83 is then advanced through the catheter over
`a 0.014" guide wire 82 to its final resting place in the target
`branch 56, and ultimately connected to a pacemaker after the
`catheter is withdrawn in order to apply electrical heart
`stimulation to that location. Guide wire 82 is only used if
`needed; it may be possible to place lead 83 without it.
`An advantage of this three-part System is that it allows a
`Standard lead (not an over-the-wire design) to be positioned
`in a transverse branch 56 which has a relatively sharp
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`angulation at its origin from the main coronary Sinus.
`Although not deflectable using an Screw adjustment mecha
`nism as described above in connection with the first
`embodiment, this embodiment can nevertheless be used to
`cannulate the coronary Sinus whether the latter is placed
`normally, higher than normal, or lower than normal. The
`angle of Outer guide 51 can be changed by inserting or
`withdrawing the inner guide 52. Inserting inner guide 52
`without obturator 53 before cannulation straightens outer
`guide 51, i.e., makes the angle of the outer guide 51
`shallower, allowing engagement of a lower origin of the
`coronary Sinus. Inserting both obturator 53 and inner guide
`52 makes the Outer guide angle even Shallower. Thus, the
`outer guide alone, the outer guide plus inner guide, and outer
`guide plus inner guide plus obturator can be used as needed
`to cannulate coronary Sinuses of varying heights of origin.
`This three-part telescoping embodiment thus eliminates
`the need for a cable System to change the curvature of the
`catheter during manipulation AS shown in FIG. 4, outer
`guide catheter 51 preferably has three bends in a manner
`similar to outer catheter 11, with the first or proximal bend
`61 ranging from about 150-180 degrees, the second
`(middle) bend 62 ranging from about 120-180 degrees, and
`the third proximal bend from 90 to 160 degrees in a direction
`opposite to that of the other two bends, as shown. Inner
`guide catheter 51 preferably has three bends in a manner
`similar to the outer catheter 11, with the first or proximal
`bend 61 ranging from about 150-180 degrees, the second
`(middle) bend 62 ranging from about 120-180 degrees, and
`the third proximal bend 63 from 90 to 160 degrees in a
`direction opposite to that of the other two bends, as shown.
`In one preferred form, outer guide 51 is 9 French diameter,
`60 cm length, inner guide 52 is made of a soft material 8
`French diameter, 68 cm length, and obturator 53 is 5 French
`diameter, 75 cm length.
`Referring to FIG. 5, obturator 53 stiffens and shapes inner
`guide 52 when inside of it. It may be pre-formed with a right
`angle bend 54 as shown to conform more easily to the shape
`of outer guide 51, but this is not essential. However, tip 71
`of obturator is 53 bent to an angle in the range of about
`150-180 degrees to better aid in introducing a lead into a
`transverse vein as described above. Obturator 53 preferably
`tapers to a blunt point having a Small opening therein just
`large enough to admit the largest Size guide wire to be used
`in the procedure, in this example, 0.038 inch.
`In an alternative version of catheter 50, the radial strength
`of the inner guide or catheter 52 prevents its collapse when
`obturator 53 is withdrawn. For this purpose, as shown in
`FIG. 6, a bend 56 in inner guide 52 is reinforced with a
`helical wire coil 55 that is embedded therein, or a series of
`Spaced wire rings or hoops. These hoop reinforcements
`prevent inner guide 52 from collapsing during withdrawal of
`obturator 53 but do not prevent inner guide 52 from bending
`in a flexible manner.
`The claims which follow define certain aspects of the
`invention but do not limit the invention. It will be evident,
`for example, that a catheter according to the invention can
`be used to reach other hard to access parts of the human
`body, both in the heart and elsewhere, due to its unique
`Structure.
`What is claimed is:
`1. A double catheter, comprising:
`an Outer, resilient catheter having shape memory and a
`hook shaped distal end configured for cannulation of
`the coronary sinus with at least one curved bend;
`an inner, pliable catheter Slidably disposed in the outer
`catheter and of greater length than the outer catheter So
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`Medtronic Exhibit 1460
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`that a distal end portion of the inner catheter can be
`extended or retracted from a distal end opening of the
`outer catheter to vary the overall length of the double
`catheter, the inner catheter having an internal lumen
`configured for the introduction of contrast media and a
`pacing lead into the coronary Sinus; and
`a mechanism operable from the proximal end of the outer
`catheter for changing the curvature of the distal end of
`the outer catheter.
`2. The double catheter of claim 1, wherein the mechanism
`for changing the curvature of the hook shaped distal end
`further comprises an obturator Slidably disposed inside of
`the inner catheter, wherein the obturator is configured to
`reduce the curvature of the hook shaped distal end when
`inserted in the inner catheter.
`3. The double catheter of claim 1, further comprising a
`balloon mounted on the outside of the distal end of the outer
`catheter positioned for occlusion of the proximal coronary
`Sinus, and a conduit permitting inflation of the balloon at the
`proximal end of the outer catheter.
`4. A double catheter, comprising:
`an Outer, resilient catheter having Shape memory and a
`hook-shaped distal end with at least one curved bend;
`an inner, pliable catheter Slidably disposed in the outer
`catheter and of greater length than the outer catheter So
`that a distal end portion of the inner catheter can be
`extended or retracted from a distal end opening of the
`outer catheter to vary the overall length of the double
`catheter, the inner catheter having an internal lumen
`suitable for the introduction of a fluid therethrough; and
`a mechanism operable from the proximal end of the outer
`catheter for changing the curvature of the distal end of
`the Outer catheter, wherein the mechanism for changing
`the curvature of the hook shaped distal end comprises
`a cable anchored to the Outer catheter at a point
`proximate the distal end of the outer catheter and at a
`point proximate the proximal end of the outer catheter,
`whereby shortening of the cable from the point proxi
`mate the proximal end of the outer catheter results in
`increased curvature of the hook shaped distal end.
`5. The double catheter of claim 4, wherein the cable runs
`inside a wall of the Outer catheter.
`6. The double catheter of claim 1, further comprising a
`mechanism operable from a proximal end of the outer
`catheter for Securing the inner catheter against Sliding move
`ment relative to the Outer catheter.
`7. The double catheter of claim 6, further comprising a
`port for introducing a fluid into a Space between the inner
`and Outer catheters.
`8. The double catheter of claim 1, wherein the hook
`shaped distal end comprises Substantially Straight Segments
`Spanning three bends.
`9. The double catheter of claim 8, wherein a first bend
`adjoining a Straight, proximal portion of the Outer catheter is
`in the range of 130 to 175, a second, intermediate bend is
`in the range of 75 to 100, and a third bend nearest the distal
`end of the outer catheter is in the range of to 130 to 175.
`10. The double catheter of claim 1, wherein the mecha
`nism for changing the curvature of the hook shaped distal
`end comprises a portion of the inner catheter configured to
`reduce the curvature of the hook shaped distal end when
`inserted in the Outer catheter.
`11. A method for placing an electrical lead in a lateral
`branch of a coronary Sinus vein using a double catheter
`including an outer catheter and an inner catheter Slidably
`disposed inside the Outer catheter, comprising:
`inserting the catheter into the coronary Sinus;
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`US 6,638,268 B2
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`advancing a guide wire through the catheter into a coro
`nary Sinus lateral branch vein;
`advancing the inner catheter out of a front end opening of
`the outer catheter along the guide wire into the branch
`vein;
`inserting the lead through the outer and inner catheters to
`a target location in the branch vein; and
`withdrawing the catheter leaving the lead in the branch
`vein.
`12. The method of claim 11, further comprising:
`adjusting the curvature of the double catheter in order to
`enter the coronary Sinus.
`13. An Outer catheter configured for use with an inner,
`pliable catheter which can be slidably disposed in the outer
`catheter and of greater length than the outer catheter So that
`a distal end portion of the inner catheter can be extended or
`retracted from a distal end opening of the outer catheter, the
`outer catheter comprising a resilient tube having shape
`memory and Sufficient Stiffness to permit advancement of
`the Outer catheter into a distal coronary Sinus, and having a
`hook-shaped distal end wherein a first bend adjoining a
`Straight, proximal portion of the outer catheter is in the range
`of 130 to 180, a second, intermediate bend is in the range
`of 75 to 100 in a direction opposite the first bend, and a
`third bend nearest the distal end of the outer catheter in the
`same direction as the second bend is in the range of to 130
`to 175.
`14. The catheter of claim 13, wherein the first bend equals
`180, rendering the outer catheter substantially J-shaped.
`15. The catheter of claim 13, wherein the first bend is in
`the range of 130-175, rendering the outer catheter substan
`tially question mark-shaped.
`16. The catheter of claim 13, wherein the outer catheter is
`made of a braided Silastic.
`17. The catheter of claim 13, wherein the outer catheter
`further comprises:
`an external inflatable cuff near the distal end of the outer
`catheter; and
`means for inflation of the cuff sufficient to permit occlu
`Sion of the proximal co