Abstract:
A catheter and a method for using the catheter for site specific delivery of agents to or collecting agents from biological spaces. The catheter includes an inner shaft longitudinally movable within and outer shaft, each shaft having at least one balloon and at least one lumen formed therein. The catheter prevents leaking through a membrane by sealing the tip passageway through the membrane with inflatable balloons on either side of the membrane. Further, the inflated balloons secure the position of the catheter relative to the biological membrane and biological space targeted for therapy or diagnosis.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    This invention relates generally to a catheter device and methods for the site-specific delivery of agents to biological spaces in medical procedures. More particularly, the invention relates to a catheter device utilizing multiple balloons and a method of site-specific delivery of agents into the pericardial space for treatment of the heart.  
           [0002]    Heart disease is the leading cause of death in the United States. One form of heart disease is caused by the formation of sclerotic plaques within blood vessels. These pathways prevent blood from flowing freely though vessels to the tissues the vessels supply. The most dangerous plaques are those which form in the coronary arteries, preventing the flow of oxygenated blood through the coronary arteries to the heart.  
           [0003]    There are generally two surgical procedures for treating heart disease. One procedure involves methods to increase blood supply to the effected areas of the heart by clearing sclerotic plaques from the existing vessels. In angioplasty, for example, a small dilating balloon is inserted into the vessel to open the vessel to increase blood flow. A second procedure involves providing new pathways for blood flow. New pathways can be created by grafting in vessels (coronary artery bypass surgery) or by inducing the growth and development of new collateral vessels (therapeutic angiogenesis).  
           [0004]    The induction of new collateral vessels can be achieved by injections of angiogenic agents directly into the heart tissue, into vessels (coronary arteries), or into the space surrounding the heart (pericardium). Direct injections of agents into the heart muscle or vessels can result in tissue injury, scarring and rapid washout of the agent into the peripheral circulatory system. Furthermore, these direct injections require surgical procedures which are more costly and require a longer recovery period than catheter based procedures. Thus, direct injections are not preferable. However, indirect injections into the pericardium avoid these difficulties.  
           [0005]    The pericardium is a membrane that surrounds the heart and isolates it from the remainder of the body. The small space between the heart and the pericardium is the pericardial space, which is filled with pericardial fluid. The pericardial fluid is in constant contact with the heart muscle and coronary arteries and provides a relatively large reservoir for sustained release of drugs compared to intra-coronary methods or direct injection. Introduction of an agent to the pericardial space allows the agent to be contained in an area localized around the heart (epicardium and epicardial vessels). This is beneficial in the following ways: 1) a lower dose of drug can be used than if given systemically due to the low volume of the pericardial fluid, 2) the low rate of turn over of the pericardial fluid allows high concentration of the agent to be maintained over a longer period, and 3) it keeps the agents out of systemic circulation where the agent may cause adverse side effects.  
           [0006]    However, the pericardial space is shallow, and thus difficult to access without puncturing (and damaging) the underlying heart tissue or coronary arteries. Previous attempts to access the pericardial space have utilized a syringe and needle combination, such as is used in pericardiocentesis, to directly inject agents into the pericardial space via the patient&#39;s chest. One of the risks inherent in such devices is the tendency for the needle to go beyond the pericardial space and to pierce the heart muscle. Some devices have utilized suction to draw the pericardial tissue towards the needle and thereby limit the distance the needle has to travel to deliver fluid to the pericardial space.  
           [0007]    One attempt to overcome some of the limitations inherent in procedures done through the patient&#39;s chest is a catheter based system disclosed in U.S. Pat. No. 5,269,326 to Verrier, which has been incorporated by reference in its entirety. Verrier discloses the use of a catheter to approach the pericardial space via the right auricle, transvenously. The device takes advantage of the fact that the right auricle lies tangential to and between the pericardium and epicardium such that the catheter steered into the right auricle will be positioned substantially parallel with the wall of the pericardium. This approach minimizes the risk of damage to the pericardium or epicardium. However, using a catheter to pierce the pericardial wall can result in pericardial fluid flowing back into the atrium, blood flowing from the atrium into the pericardial space, and the therapeutic agent could end up being systemically administered.  
           [0008]    Another approach to introducing medicaments directly into the pericardium is disclosed in U.S. Pat. No. 5,797,870 to March et al., which has been incorporated by reference in its entirety. March et al. discloses delivering a gene therapy agent into the pericardial sac either surgically or by transvascular means. In the catheter based embodiment the distal end of the catheter comprises a hypotube configured as a helical coil which is to be screwed into a heart wall to access the pericardial space. Like the device and method disclosed in Verrier, the device and method of March et al. is also susceptible to the backflow of pericardial fluid into the atrium and the ultimate systemic administration of the therapeutic agent.  
           [0009]    What is needed, and what is provided by the present invention, is a catheter based device and method that accesses the pericardial space through the right auricle but is capable of sealing the access site so that the therapeutic agent is locally administered and flow between the auricle and the pericardial space is minimized.  
         BRIEF SUMMARY OF THE INVENTION  
         [0010]    The present invention provides an improved agent delivery catheter which obviates, for practical purposes, the above mentioned limitations.  
           [0011]    One feature of the invention is a device for accessing the pericardial space while minimizing the risk of injury to the heart during the pericardial catheterization.  
           [0012]    Another feature of the invention is a catheter device which minimizes leakage from the pericardium and bleeding from the atrium into the pericardial space during catheterization of a defined biological space, such as the pericardial space.  
           [0013]    Another feature of the invention is to provide a catheter device which minimizes longitudinal movement of the catheter from a site-specific location during the delivery or collection of agents from a defined biological space, such as the pericardial space.  
           [0014]    Another feature of the invention is a device having a lumen which communicates with the pericardial fluid for the site specific introduction of agents into or collection of fluid from the pericardial space.  
           [0015]    In accordance with one aspect of the present invention, the catheter includes an inner shaft longitudinally movable within an outer shaft, wherein each shaft has at least one lumen within it and at least one balloon attached to it.  
           [0016]    In accordance with an additional embodiment of the present invention, the catheter includes an inner shaft longitudinally movable within an outer shaft, wherein inner shaft has at least one lumen within it and at least one balloon attached to it.  
           [0017]    In accordance with an additional embodiment of the present invention, the catheter includes an inner shaft longitudinally movable within an outer shaft, wherein each shaft has at least one lumen within it and at least two deployable wire supports attached thereto and includes at least one balloon attached therebetween.  
           [0018]    The catheter may include at least one lumen in each shaft, wherein the lumen may contain a guidewire, a wire support deployment mechanism, a balloon inflation source, or an agent delivery or collection source.  
           [0019]    The catheter may include marker bands on each shaft, such that the marker bands can be used to detect the position of the shafts relative to one another or relative to the pericardial space.  
           [0020]    The inner shaft of the catheter may include a distal tip to penetrate the surface membrane of the biological space. The tip may further be radio-opaque so that its position can be detected during use.  
           [0021]    The above described and many other features and attendant advantages of the present invention will become apparent from a consideration of the following detailed description when considered in conjunction with the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]    A detailed description of the embodiments of the invention will be made with reference to the accompanying drawings, wherein like numerals designate corresponding parts in the several figures.  
         [0023]    [0023]FIG. 1 is a diagrammatic representation of the heart;  
         [0024]    [0024]FIG. 2 is a side view of an exemplary embodiment of the present invention;  
         [0025]    FIGS.  3 A- 3 D are a cross sectional views of the A) outer shaft; B) inner shaft; C) inner shaft within the outer shaft; and D) the present invention within a guide catheter;  
         [0026]    FIGS.  4 A- 4 D are side views of an exemplary embodiment of the present invention in various stages of application;  
         [0027]    FIGS.  5 A- 5 D are side views of the distal end of an another exemplary embodiment of the present invention in various stages of application;  
         [0028]    FIGS.  6 A- 6 C are side views of A) another exemplary embodiment of the present invention; B) the distal portion of the embodiment with the inner shaft deployed beyond the outer shaft C)the inner shaft non-deployed within the outer shaft;  
         [0029]    FIGS.  7 A- 7 C are side views of A) another exemplary embodiment of the present invention; B) the distal portion of the outer shaft of the present invention; C)the inner shaft extended beyond the outer shaft;  
         [0030]    FIGS.  8 A- 8 C are side views of A) another exemplary embodiment of the present invention; B) the distal portion of the outer shaft of the present invention; C)the inner shaft extended beyond the outer shaft; and  
         [0031]    FIGS.  9 A- 9 C are side views of A) another exemplary embodiment of the present invention; B) the distal portion of the outer shaft containing the non-deployed inner shaft; C) the distal portion of the outer shaft with the inner shaft deployed. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0032]    Disclosed herein is a detailed description of various illustrated embodiments of the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention. The section titles and overall organization of the present detailed description are for the purpose of convenience only and are not intended to limit the present invention.  
         [0033]    [0033]FIG. 1 illustrates the heart  2  generally. The pericardium, or pericardial sac or membrane  4 , surrounds the heart  2  (epicardium, myocardium and endocardium). A portion of the pericardium has been cut away to show the underlying heart, and the small space between the heart and the pericardium is the pericardial space  6 . The cut edge of the pericardium is  8 . The pericardial space  6  is one example of a defined biological space site-specifically targeted for the delivery or collection of agents by catheterization.  
         [0034]    Detailed Description of the First Embodiment  
         [0035]    As illustrated in FIG. 2, one embodiment of the catheter  10 , generally comprises an inner shaft  12  longitudinally movable within an outer shaft  14  along the catheter longitudinal axis  16 . The inner shaft  12  has at its most distal end an inner shaft distal tip  18 , and a first distal balloon  20  is located proximal to the inner shaft distal tip  18  along the catheter longitudinal axis. At the most proximal end of the inner shaft is a plunger  22 . The outer shaft  14  has at its most distal end an outer shaft distal tip  23 , and a second proximal balloon  24  is located proximal to the outer shaft distal tip  23  along the catheter longitudinal axis  16 . The outer shaft has a handle  26  which is fixed to the outer shaft and a hub  28  which is fixed to the outer shaft, but longitudinally movable along the inner shaft. At the proximal end of the catheter are ports  30 . The ports  30  communicate with the lumens of the inner shaft  12  and outer shafts  14  allowing for access into the catheter by elements including, but not limited to guidewires, balloon inflation sources, and/or agent delivery sources. Lumens generally extend from the proximal ends to open distal ends of the inner or outer shaft,  12  or  14  respectively, or from a port  30  which communicates with the lumen to allow access to elements including guidewires, balloon inflation sources and/or agent delivery or collection sources.  
         [0036]    As illustrated in FIG. 3A, the outer shaft  14  has an outer shaft interior wall  40  and an outer shaft exterior wall  42 . The outer shaft interior wall  40  defines an outer shaft central lumen  44 . Outer shaft peripheral lumens  46  are formed within outer shaft  14  and are located between the outer shaft interior wall  40  and outer shaft exterior wall  42 . As illustrated in FIG. 3B, the inner shaft  12  has an inner shaft interior wall  32  and an inner shaft exterior wall  34 . The inner shaft interior wall  32  defines an inner shaft central lumen  36 . Inner shaft peripheral lumens  38  are formed within the inner shaft  12  and are located between the inner shaft interior wall  32  and inner shaft exterior wall  34 . Alternatively, lumens may be formed in the inner shaft  12  so that the lumens are arranged axially around the catheter longitudinal axis  16 .  
         [0037]    As illustrated in FIG. 3C, when assembled, the inner shaft  12  is located within the outer shaft central lumen  44  of the catheter. The catheter of the present invention may be used with an outer guide catheter  50  to guide the catheter to the pericardial membrane.  
         [0038]    As illustrated in FIG. 3D, the inner shaft distal tip  18  can have orifices  48  that extend from the inner shaft central lumen  36  and/or the inner shaft peripheral lumens  38  to the inner shaft exterior wall  34  for the delivery or collection of agents to the pericardial space.  
         [0039]    The present invention also contemplates a method of using a catheter for the delivery or the collection of agents from a target biological space in vivo. When used to catheterize the pericardial space the balloons act to seal off the passageway in the pericardium made by the inner shaft distal tip. This is to prevent pericardial fluid from flowing into the atrium, to prevent blood in the atrium from flowing into the pericardial space, and to insure that the therapeutic agent delivered stays within the space and is not systemically administered. Further, the balloons act to stabilize the catheter within the pericardial space by being inflated against the inner and outer pericardial membrane.  
         [0040]    The catheter of the present invention can be used to approach the pericardial space via the right auricle, as described by Verrier. This method involves reaching the pericardial space by guiding a catheter through one of the vena cavae to the right atrium, then into the right auricle. By this approach, the catheter is substantially parallel to the wall of the pericardium, so that when the catheter is advanced through the pericardium there is a low risk of piercing the underlying heart (see FIG. 1). Alternatively, the catheter of the present invention can be used to access the pericardial space via the ventricular space. For example, the catheter can be used to access the right atrium, pierce the septum and thereafter access the left ventricle. Once in the left ventricle, the catheter is used to pierce the ventricular wall to access the pericardial space.  
         [0041]    As illustrated in FIGS.  4 A-D, the catheter  10  when inserted/introduced to the tissue preferably has the inner shaft  12 , distal balloon  20 , and inner shaft distal tip  18  retracted into the outer shaft  14  (FIG. 4A). The user advances the catheter toward the pericardial membrane using the handle  26  to apply forward pressure (thick arrow). When the catheter is advanced so that it is proximal to the pericardial membrane the inner shaft  12  is moved longitudinally relative to the outer shaft  14  by applying forward pressure to the plunger  22  (thin arrow). The inner shaft distal tip  18  is then moved forward to pierce the pericardial membrane. The user advances the inner shaft until distal balloon  20  is situated within the pericardial space (thin arrow; FIG. 4B). The distal balloon  20  is then inflated by a balloon inflation source in communication with a port  30  and lumen in the inner shaft  12  (FIG. 4C). The user advances the outer shaft  14  by moving the hub  28  longitudinally forward (open arrow) relative to the inner shaft  12  until the proximal balloon  24  is firmly opposed to the outer surface of the pericardial membrane. The proximal balloon  24  is then inflated by a balloon inflation source in communication with a port  30  and lumen in the outer shaft  12  (FIG. 4D). Agents can then be infused or collected via the inner shaft distal tip in the pericardial space.  
         [0042]    Alternatively, as discussed previously, the catheter can also be used to access the pericardial space by entering the right atrium, crossing the septum and entering the left ventricle. As discussed above, the catheter inner shaft distal tip  18  is moved forward to pierce the pericardial membrane and the inner shaft is advanced until distal balloon  20  is situated within the pericardial space. The distal balloon  20  is inflated, the outer shaft  14  is advanced until the proximal balloon  24  is firmly opposed to the outer surface of the pericardial membrane. The proximal balloon  24  is then inflated and agents can then be infused or collected via the inner shaft distal tip in the pericardial space.  
         [0043]    Detailed Description of the Second Embodiment  
         [0044]    In an alternate embodiment illustrated in FIGS.  5 A-D, catheter  110  has an inner shaft  112  longitudinally movable relative to outer shaft  114 . However, in this embodiment outer shaft  114  further includes a proximal pusher portion  115  which is separable from the distal end portion  116  of the outer shaft  114  to reveal inner shaft  112 . Outer shaft  114  has distal tip  118 , which can be a needle designed to pierce membranes and tissue, and a first balloon  120  proximal to the distal tip  118  and inner shaft  112  has distal tip  123  and second balloon  124  proximal to distal tip  123 . As with catheter  10 , outer shaft  114  of catheter  110  has a handle  26  which is fixed to proximal pusher portion  115  of outer shaft  114  and provides longitudinal movement to pusher  115 . In most other respects, catheter  110  has the same features at its proximal end (not shown) as catheter  10 .  
         [0045]    Proximal pusher portion  115  has a distal end  117  that is engageable and retractable with the distal end portion  116  of outer shaft  114  by a threading or locking mechanism and in other ways known to those of skill in the art. As illustrated in FIG. 5A, when catheter  110  is introduced into the body proximal pusher portion  115  is engaged with distal end portion  116  of outer shaft  114  and inner shaft  112  is contained within outer shaft  114 . The user applies forward pressure to handle  26  to advance catheter  110  towards the pericardial membrane  4 . Outer shaft distal tip  118  is moved forward to pierce the pericardial membrane and outer shaft  114  is advanced forward until first balloon  120  is within the pericardial space (FIG. 5B).  
         [0046]    As illustrated in FIG. 5C, first balloon  120  is inflated by a balloon inflation source in communication with a proximal port and lumen (not shown) as in catheter  10 . Proximal pusher portion  115  is then retracted, revealing inner shaft  112  and second balloon  124 . Second balloon  124  is inflated in similar fashion to catheter  10  and agents can be infused into or collected from the pericardial space. Upon completion of the procedure, the second balloon  124  is deflated and pusher  115  is advanced distally to enclose inner shaft  112  and engage with distal end portion  116  of outer shaft  114 . First balloon  120  is deflated and catheter  110  can then be removed from the body.  
         [0047]    Detailed Description of the Third Embodiment  
         [0048]    As illustrated in FIG. 6, a third embodiment of the catheter  610 , generally comprises an inner shaft  612  longitudinally movable within an outer shaft  614  along the catheter longitudinal axis  616 . The inner shaft  612  defined by an inner shaft interior wall  661  defining inner shaft lumen  613 , and an inner shaft exterior wall  662  having at its most distal end an inner shaft distal tip  618 . Inflation ports  665  and  667  provide access to inner shaft lumen  613 . A pliable inflatable balloon  650 , positioned to enclose inflation ports  665  and  667 , is attached to inner shaft exterior wall at the most proximal end of the inner shaft along the longitudinal axis of the catheter  610 . The outer shaft  614 , defined by outer shaft interior wall  657  defining outer shaft lumen  615 , and outer shaft exterior wall  658 , has at its most distal end an outer shaft distal tip  621 . The outer shaft  614  has a handle  626  which is fixed to the outer shaft and a hub  628  which is fixed to the outer shaft, but longitudinally movable along the inner shaft. At the proximal end of the catheter are ports  630 . The ports  630  communicate with inner shaft lumen  613  and outer shaft lumen  615  allowing for access into the catheter by elements including, but not limited to guidewires, balloon inflation sources and/or agent delivery sources. Lumens  613  and  615  generally extend from the proximal ends to open distal ends of the inner or outer shaft,  612  or  614  respectively, or from a port  630  which communicates with lumens  613  and  615 , respectively, to allow access to elements including guidewires, wire support deployment mechanisms, balloon inflation sources, and/or agent delivery or collection sources.  
         [0049]    As illustrated and in accordance with the Verrier catheter insertion technique, when catheter  610  is introduced into the body, inner shaft  612  is contained within outer shaft  614 . The user applies forward pressure to handle  626  to advance catheter  610  towards the pericardial membrane  604 . Outer shaft  614  is positioned proximal to pericardial membrane as inner shaft distal tip  618  is moved forward to pierce the pericardial membrane. Outer shaft  614  is then advanced forward until inner shaft distal tip  618  is within the pericardial space. Pliable inflatable balloon  650  is inflated by a balloon source in communication with port  630  and lumen in inner shaft  6   12 . Pliable inflatable balloon  650  serves to seal the opening created in the pericardial membrane  604 , thereby permitting isolated infusion of medicament.  
         [0050]    Upon completion of the procedure, pliable inflatable balloon  650  is deflated. Inner shaft  612  retracts within outer shaft  614 . Catheter  610  can then be removed from the body.  
         [0051]    As discussed with respect to previous embodiments, the catheter can also be used to access the pericardial space by entering the right atrium, crossing the septum and entering the left ventricle.  
         [0052]    Detailed Description of the Fourth Embodiment  
         [0053]    As illustrated in FIG. 7, a fourth embodiment of the catheter  710 , generally comprises an inner shaft  712  longitudinally movable within an outer shaft  714  along the catheter longitudinal axis  716 . The inner shaft  712  defined by an inner shaft interior wall  761  defining an inner shaft lumen  713 , and an inner shaft exterior wall  762  having at its most distal end an inner shaft distal tip  718 . Inflation ports  765  and  767  provide access to inner shaft lumen  713 . A pliable inflatable balloon  750 , positioned in fluid communication with inflation ports  765  and  767  is attached to inner shaft exterior wall  762  at the most proximal end of the inner shaft  712  along the longitudinal axis  716  of the catheter  710 . A first wire support  780  has a distal portion positioned proximal to inner shaft distal tip  718 , and in communication with first wire support deployment mechanism  782  through ports  784  and  785 , whereby the proximal portion flexibly attached to inner shaft exterior wall  786 . First wire support deployment mechanism is in communication with outer shaft handle  726  through a deployment conduit  788 . Deployment conduit  788  is used to slidably urge deployment mechanism  782  towards deployment ports  784  and  785 , resulting in deployment of first wire support  780 . The outer shaft  714  enclosing the inner shaft  712  is defined by an outer shaft interior wall  757  defining outer shaft lumen  715 , and outer shaft exterior wall  758 . The outer shaft  714  has at its most distal end an outer shaft distal tip  721 . Second wire support  790  distal portion is positioned along the catheter longitudinal axis  716  adjacent to and flexibly attached to outer shaft exterior wall  758 . Second wire support proximal portion communicates with inner shaft exterior wall  757  through ports  794  and  795 . The outer shaft has a handle  726  which is fixed to the outer shaft and a hub  728  which is fixed to the outer shaft, but longitudinally movable along the inner shaft. At the proximal end of the catheter are ports  730 . The ports  730  communicate with the lumen  713  of the inner shaft  712  and outer shaft lumen  715  allowing for access into the catheter by elements including, but not limited to guidewires, wire support deployment mechanisms, balloon inflation sources and/or agent delivery sources. Lumens  713  and  715 , respectively, generally extend from the proximal ends to open distal ends of the inner or outer shaft,  712  or  714  respectively, or from a port  730  which communicates with the lumens  713  and  715 , respectively, to allow access to elements including guidewires, wire support deployment mechanisms, balloon inflation sources, and/or agent delivery or collection sources.  
         [0054]    First wire support deployment mechanism  782  is engageable and retractable by a threading or locking mechanism and in other ways known to those of skill in the art. When catheter  710  is introduced into the body first wire support  782  is retracted and positioned along the longitudinal axis of the catheter  710  proximal to inner shaft  712 , which is contained within outer shaft  714 . Second wire support  790  is retracted and positioned proximal to outer shaft exterior wall  758  along the longitudinal axis of the catheter  710 . The user applies forward pressure to handle  726  to advance catheter  710  towards the pericardial membrane  704 . Inner shaft distal tip  718  is moved forward to pierce the pericardial membrane  704 . Once outer shaft distal tip  721  is positioned proximal to pericardial membrane  704 , inner shaft distal tip  418  is advanced through the pericardial membrane  704 . Forward advancement of inner shaft  712  slidably urges second wire support  790  through deployment port  794  and  795 , thereby deploying second wire deployment anchor  491 . Outer shaft  714  is advanced forward until inner shaft distal tip  718  is within the pericardial space and second wire support  790  contacts pericardial membrane  704 . First wire support  780  is deployed to stabilize catheter  710 . Pliable inflatable balloon  750  is inflated thereby isolating the pericardial space from the right atrium. Pliable inflatable balloon  750  is inflated by a balloon source in communication with ports  784  and  785  and lumen in inner shaft  712 , and medicament is infused into the isolated pericardial region. Upon completion of the procedure, pliable inflatable balloon  750  is deflated. Inner shaft distal tip  718  and first and second wire supports,  780  and  790  respectively, are retracted. Catheter  710  can then be removed from the body.  
         [0055]    Detailed Description of the Fifth Embodiment  
         [0056]    As illustrated in FIG. 8, a fifth embodiment of the catheter  810 , generally comprises an inner shaft  812  longitudinally movable within an outer shaft  814  along the catheter longitudinal axis  816 . The inner shaft  812  is defined by an inner shaft interior wall  861  defining an inner shaft lumen  813 , and an inner shaft exterior wall  862  having at its most distal end an inner shaft distal tip  818 . A first wire support  880  positioned proximal to the most distal end of the inner shaft  812  along the longitudinal axis  816  of the catheter  810 , has a distal portion in communication with first wire support deployment mechanism  882  through a deployment ports  865  and  867 , and a proximal portion flexibly attached to inner shaft exterior wall  886 . First wire support deployment mechanism is in communication with outer shaft handle  826  through a deployment conduit  888 . Deployment conduit  888  is used to slidably urge deployment mechanism  882  towards deployment ports  865  and  867  resulting in first wire support  880  deployment. The outer shaft  814  enclosing the inner shaft  812  is defined by an outer shaft interior wall  857  and outer shaft exterior wall  858 . The outer shaft  814  has at its most distal end an outer shaft distal tip  821 . Second wire support  890  distal portion is positioned along the catheter longitudinal axis  816  adjacent to and flexibly attached to outer shaft exterior wall  858 . Second wire support proximal portion communicates with inner shaft exterior wall  857  through ports  894  and  895 . The outer shaft has a handle  826  which is fixed to the outer shaft and a hub  828  which is fixed to the outer shaft, but longitudinally movable along the inner shaft. At the proximal end of the catheter are ports  830 . The ports  830  communicate with the lumen  813  of the inner shaft  812  and outer shaft lumen  815  allowing for access into the catheter by elements including, but not limited to guidewires, wire support deployment mechanisms, and/or agent delivery sources. Lumens  813  and  815 , respectively, generally extend from the proximal ends to open distal ends of the inner or outer shaft,  812  or  814  respectively, or from a port  830  which communicates with the lumens  813  and  815 , respectively, to allow access to elements including guidewires, wire support deployment mechanisms, and/or agent delivery or collection sources.  
         [0057]    First wire support deployment mechanism  882  is engageable and retractable by a threading or locking mechanism and in other ways known to those of skill in the art. When catheter  810  is introduced into the body first wire support  882  is retracted positioned along the longitudinal axis of the catheter  810  proximal to inner shaft  812 , which is contained within outer shaft  814 . Second wire support  890  is retracted; positioned proximal to outer shaft exterior wall  858  along the longitudinal axis of the catheter  810 . The user applies forward pressure to handle  826  to advance catheter  810  towards the pericardial membrane  804 . Inner shaft distal tip  818  is moved forward to pierce the pericardial membrane  804 . Once outer shaft distal tip  821  is positioned proximal to pericardial membrane  804 , inner shaft distal tip  818  is advanced through the pericardial membrane  804 . Forward advancement of inner shaft distal tip  818  slidably urges second wire support  890  through deployment ports  894  and  895 , structurally interacting with second wire deployment anchor  891 . Outer shaft  814  is advanced forward until inner shaft distal tip  818  is within the pericardial space and second wire support  890  contacts pericardial membrane  804 . First wire support  880  is deployed to stabilize catheter  810 , and medicament is injected into the pericardial area. Upon completion of the procedure, inner shaft distal tip  818  and first and second wire supports,  880  and  890  respectively, are retracted. Catheter  810  can then be removed from the body.  
         [0058]    Detailed Description of the Sixth Embodiment  
         [0059]    As illustrated in FIG. 9, a sixth embodiment of the catheter  910 , generally comprises an inner shaft  912  longitudinally movable within an outer shaft  914  along the catheter longitudinal axis  916 . The inner shaft  912  defined by an inner shaft interior wall  961  defining inner shaft lumen  913 , and an inner shaft exterior wall  962  having at its most distal end an inner shaft distal tip  918 . Inflation ports  965  and  967  provide access to inner shaft lumen  913 . A pliable inflatable balloon  950 , positioned to enclose inflation ports  965  and  967 , is attached along the longitudinal axis of the catheter  910 . The outer shaft  914  enclosing the inner shaft is defined by an outer shaft interior wall  957  and outer shaft exterior wall  958  defining outer shaft lumen  915 . Outer shaft  914  has at its most distal end an outer shaft distal tip  921 , and a wire support  980  attached to outer shaft exterior wall  958 , and is functionally connected to inner shaft exterior wall  962  through deployment ports  970  and  971  respectively. Wire support  980  is located proximal to the outer shaft distal tip  921  along the catheter longitudinal axis  916 . The outer shaft  914  has a handle  926  which is fixed to the outer shaft and a hub  928  which is fixed to the outer shaft  914 , but longitudinally movable along the inner shaft. At the proximal end of the catheter are ports  930 . The ports  930  communicate with lumens  912  and  914  respectively, thereby allowing for access into the catheter by elements including, but not limited to guidewires, wire support deployment mechanisms, balloon inflation sources and/or agent delivery sources. Lumens generally extend from the proximal ends to open distal ends of the inner or outer shaft,  912  or  914  respectively, or from a port  930 , to allow access to elements including guidewires, wire support deployment mechanisms, balloon inflation sources, and/or agent delivery or collection sources.  
         [0060]    Wire support deployment mechanism  980  has a distal end  981  that is flexibly attached to outer shaft exterior wall  958  proximal to outer shaft distal end portion  921  of outer shaft  914  by a threading or locking mechanism and in other ways known to those of skill in the art. When catheter  910  is introduced into the body wire support deployment mechanism  980  is retracted, position proximal to outer shaft exterior wall  958  along the longitudinal axis of catheter  910 , and having inner shaft  912  is contained within outer shaft  914 . The user applies forward pressure to handle  926  to advance catheter  910  towards the pericardial membrane  904 . As inner shaft distal tip  918  is moved forward, wire support  980  slidably deploys through deployment ports  970  and  971  respectively, and engages the pericardial tissue thereby providing support to catheter  910  forward advancement continuing until inner shaft distal tip  918  is within the pericardial space. Pliable inflatable balloon  950  is inflated by a balloon inflation source in communication with port  930  and medicament is then infused into the isolated pericardial region. Upon completion of the procedure, pliable inflatable balloon  950  is deflated and inner shaft distal end  918  and wire support  980  are retracted. Catheter  910  can then be removed from the body.  
         [0061]    In all of the aforementioned embodiments the catheter can be used to access the pericardial space using the Verrier technique or, alternatively, by entering the right atrium, crossing the septum and entering the left ventricle.  
         [0062]    Although the present invention has been described in terms of the illustrated embodiment above, numerous modifications and/or additions to the above-described illustrated embodiments would be readily apparent to one skilled in the art.  
         [0063]    The catheter inner shaft and outer shaft can be made of various materials known to those skilled in the art, including, but not limited to nylon, Pebax and polyethelene. The shaft materials can be selected so as to maximize column strength through the longitudinal length of the shaft. Further, the shaft materials can be braided, so as to provide sufficient column strength. The shaft materials can also be selected so as to allow the inner shaft to move smoothly within the outer shaft of the catheter and/or to allow the device to move smoothly within a guide catheter. The shaft materials can also be selected so as to maximize bonding of the shafts to the balloon materials.  
         [0064]    In some embodiments, the catheter  10 / 110  can be used with a guide catheter  50  to assist in guiding the catheter to the intended target. Such guide catheters are preferably about 6-8 Fr in diameter.  
         [0065]    The catheter outer shaft exterior wall  42  is preferably between about 3-7 Fr. in diameter. The outer shaft exterior wall  42  is most preferably about 4.5 Fr. The outer shaft interior wall  40  is preferably between about 2-5 Fr. in diameter. The outer shaft interior wall  40  is most preferably about 3 Fr.  
         [0066]    The catheter inner shaft exterior wall  34  is preferably between about 2-5 Fr. in diameter. The inner shaft exterior wall  34  is most preferably about 3 Fr. The inner shaft interior wall  32  is preferably between about 1-4 Fr. in diameter. The inner shaft interior wall is most preferably about 2 Fr.  
         [0067]    The inner shaft distal tip  18 / 118 . can be either blunt or sharp. Further, inner shaft distal tip  18 / 118  can be open or closed at the most distal end. Where the inner shaft distal tip is sharp, the tip can be a needle designed to pierce membranes and tissue. The needle can be made of various appropriate materials including, but not limited to, stainless steel or titanium. The needle can be hollow and can have orifices  48  to provide access via a lumen to the pericardial space for the delivery or collection of agents from the pericardial space. The distal tip can be radio-opaque to aid in the visualization during a catheterization.  
         [0068]    The distal and proximal balloons,  20 / 120  &amp;  24 / 124 , can be made of various materials known to those of skill in the art, including, but not limited to, latex, Kraton, polyurethane or any other biocompatible, elastomeric material, or other soft materials. The materials of the balloons may be selected so as to maximize pliability and/or reduce the risk of damage to tissues. Various balloon inflation sources known to those of skill in art can be used, such as a hand syringe in communication with lumens of the inner and/or outer shafts  12  &amp;  14  via the appropriate proximal ports.  
         [0069]    The distal balloon  20  and the proximal balloon  24 , when inflated, are preferably between about 3-5 mm in diameter. The balloons are most preferably about 3 mm in diameter. The balloons are preferably between about 1-2 cm in length. The balloons are most preferably about 1 cm long. However, the length of the balloons can be selected to be as short as possible so as to minimize tissue damage.  
         [0070]    The catheter  10 / 110  may have a plurality of ports  30  which communicate with the lumens  36 ,  38 ,  44 , and  46  within the inner shaft  12 / 112  and outer shaft  14 / 114 . In one embodiment, the inner shaft central lumen  36  provides a channel for a guidewire  52 , a first inner shaft peripheral lumen  38  provides a channel for gasses or liquids to fill the distal balloon  20 , and a second inner shaft peripheral lumen  38  provides a channel for the agent to be delivered to the pericardial space via the inner shaft distal tip  18  and out of the orifices  48 . The outer shaft central lumen  44  contains the inner shaft  12  within it, and a first outer shaft peripheral lumen  46  provides a channel for contrast media or saline to fill the proximal balloon  24 .  
         [0071]    In an alternate embodiment, the inner shaft central lumen  36  provides a channel for a guidewire  52 . Once the catheter  10 / 110  is in place, the guidewire  52  can be retracted from the inner shaft central lumen  36 , and the agent can be delivered to the biological space via the inner shaft central lumen  36  to the inner shaft distal tip  18 / 118 .  
         [0072]    In another alternate embodiment, one or both balloons could be made of microporous materials so that agents are delivered by the balloons instead of or in addition to the inner shaft distal tip  18 / 118  and or orifices  48 .  
         [0073]    In another alternate embodiment, the guidewire  52  may be hollow and serve as a pathway for the delivery of agents during catheter use or may remain in place in the pericardial space after removal of the catheter.  
         [0074]    The catheter can be visualized by thoroscopic, fluroscopic or ultrasonic visualization to determine its position in vivo, as described by Verrier in Persistent primary coronary dilation induced by transatrial delivery of nitroglycerin into the pericardial space: A novel approach for local cardiac drug delivery.  J of Am. Coll. Cardiol.  ( 1999 ), herein incorporated by reference. Alternatively, imaging systems such as the Webster-Biosense NOGA system or an ultrasound system such as the Mayo-Accuson Inside-Out system may be used to determine the position of the catheter in vivo. Further, confirmation of access to the pericardial space can be confirmed by injection of contrast dye.  
         [0075]    In some embodiments inner shaft  12 / 112  and/or outer shaft  14 / 114  may include marker bands  54  which can be used to detect the position of the balloons and/or shafts relative to one another or relative to the pericardial space. The marker bands can be made of materials including, but not limited to platinum, gold or tantalum, which may incorporated into the shaft walls or placed on the surface. In some embodiments, a guidewire  52  can be advanced through the catheter into the pericardial space to confirm the position in the pericardial space. In some embodiments, radio-opaque markers at the inner shaft distal end  18 / 118  can be used to visualize the location of the catheter using fluoroscopy during the procedure.  
         [0076]    Where guidewires  52  are used with the catheter, the guidewires can be made of materials including, but not limited to stainless steel. The guidewire materials can be selected such that the surface of the guidewire moves smoothly within the lumen. The guidewires are preferably from about 0.014-0.038 inches and most preferably from about 0.014 to about 0.018 inches in diameter.  
         [0077]    Agents include any one of or a combination of several agents which are gas, liquid or solid and which may be delivered or collected from the pericardial space for therapeutic or diagnostic purposes. Therapeutic agents include biologically active substances, or substances capable of eliciting a biological response, including, but not limited to endogenous substances (growth factors or cytokines, including, but not limited to basic fibroblast growth factor, acidic fibroblast growth factor, vascular endothelial growth factor, angiogenic factors), viral vectors, DNA capable of expressing proteins, sustained release polymers, unmodified or modified cells. Therapeutic agents include angiogenic agents which induce the formation of new blood vessels. For diagnostic purposes, imaging fluid may be injected into the right atrium and the pericardial space for fluid imaging of the heart and pericardial fluid may be withdrawn for diagnostic analysis. Further, electrical devices may be implanted to detect electrical signals in the heart or deliver them to the heart.  
         [0078]    The rate of delivery of agents can be selected so as to reduce tissue damage. The rate of delivery of agent can depend upon at least the size and number of orifices and the pressure under which the agent is passed through the orifices. The rate of delivery can be controlled by osmotic pump. An agent delivery or collection device can be a syringe or infusion pump for slow, precise, measured delivery, in communication with a lumen via a port  30  in the inner shaft  12 / 112 .  
         [0079]    Other biological spaces which may be accessed by this catheter include but are not limited to the sub-dural and sub-arachnoid spaces of the central nervous system and the bladder. In closing, it is noted that specific illustrative embodiments of the invention have been disclosed hereinabove. However, it is to be understood that the invention is not limited to these specific embodiments. Accordingly, the invention is not limited to the precise embodiments described in detail hereinabove. With respect to the claims, it is applicant&#39;s intention that the claims not be interpreted in accordance with the sixth paragraph of 35 U.S.C. §112 unless the term “means” is used followed by a functional statement. Further, with respect to the claims, it should be understood that any of the claims described below can be combined for the purposes of the invention.