Abstract:
A hemostasis device including a shaft having a forward end, at least one anchor balloon mounted on the shaft at the forward end and at least one electrical resistance heating element, mounted on the main shaft forward of the at least one anchor element and being operable to enhance hemostasis.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is related to and claims priority of PCT Application PCT/IL2004/000100, filed Feb. 3, 2004, the disclosure of which is hereby incorporated by reference, entitled “METHODS AND APPARATUS FOR HEMOSTASIS FOLLOWING ARTERIAL CATHETERIZATION” under CFR section 1.78(a)(4) and CFR section 1.78(a)(5)(i). 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to catheterization systems and methodologies generally and more particularly to post-catheterization closure. 
       BACKGROUND OF THE INVENTION 
       [0003]    Various techniques are known for arterial catheterization. Following arterial catheterization, it is necessary to promote hemostasis quickly and without undue hardship for the patient. 
         [0004]    Applicant&#39;s U.S. Pat. Nos. 5,728,134 and 6,048,358, and Published PCT Patent Applications WO 98/11830 and WO 00/02488 describe methods and apparatus for hemostasis that greatly simplify hemostasis and thus greatly reduce patient discomfort following arterial catheterization. These patent documents, the disclosures of which are hereby incorporated by reference, and the prior art referenced therein are considered to represent the state of the art. 
       SUMMARY OF THE INVENTION 
       [0005]    The present invention seeks to provide improved systems and methodologies for post-catheterization closure. 
         [0006]    There is thus provided in accordance with a preferred embodiment of the present invention a hemostasis device including a shaft having a forward end, at least one anchor balloon mounted on the shaft at the forward end and at least one electrical resistance heating element, mounted on the main shaft forward of the at least one anchor element and being operable to enhance hemostasis. 
         [0007]    In accordance with a preferred embodiment of the present invention the at least one anchor element comprises an anchor balloon. Preferably, electrical resistance heating element is configured to be suitable for passage through a catheter introducer for introduction thereof to a desired hemostasis location and to be foldable over the forward end of the shaft and the at least one anchor balloon during the passage. 
         [0008]    In accordance with another preferred embodiment of the present invention, the electrical resistance heating element is configured to be foldable over the forward end of the shaft in a manner that portions of the electrical resistance heating element generally do not overlap when so folded. Preferably, the electrical resistance heating element is configured to define a plurality of leaves. Optionally and preferably, the plurality of leaves are arranged generally in a four-leaf clover configuration. 
         [0009]    In accordance with yet another preferred embodiment of the present invention the electrical resistance heating element is resiliently bendable to be foldable over the forward end of the shaft and to extend radially outward from the shaft prior to and following folding thereof. 
         [0010]    In accordance with a further preferred embodiment of the present invention the hemostasis device also includes at least one peripheral balloon, disposed rearwardly of the at least one anchor balloon along the shaft. 
         [0011]    In accordance with a still further preferred embodiment of the present invention the shaft includes at least a first lumen and a second lumen, the first lumen being operative to supply fluid to the anchor balloon for inflation thereof and the second lumen being operative to supply fluid to the peripheral balloon for inflation thereof. 
         [0012]    In accordance with yet a further preferred embodiment of the present invention the electrical resistance heating element is formed of foil. 
         [0013]    In accordance with another preferred embodiment of the present invention the hemostasis device also includes a first and a second conductor operative to supply electrical power to the electrical resistance heating element, the first conductor extending through the first lumen and the second conductor extending through the second lumen. 
         [0014]    There is also provided in accordance with a preferred embodiment of the present invention a method for accelerating hemostasis of an artery having a puncture after arterial catheterization, the method including the steps of following arterial catheterization, introducing through a catheter introducer a hemostasis device including a shaft having a forward end, at least one anchor element mounted on the shaft at the forward end and at least one electrical resistance heating element, mounted on the shaft forward of the at least one anchor balloon, such that a forward end of the hemostasis device lies exterior of the artery adjacent a puncture in a wall of the artery, accelerating hemostasis in the vicinity of the puncture by operating the electrical resistance heating element, thereby shortening the time required for hemostasis and following hemostasis, removing the hemostasis device from the patient. 
         [0015]    In accordance with a preferred embodiment of the present invention the introducing the hemostasis device includes passing the hemostasis device through the catheter introducer including folding the at least one electrical resistance heating element over the forward end of the shaft and the at least one anchor balloon. Preferably, the folding is such that portions of the electrical resistance heating element generally do not overlap when they are folded. 
         [0016]    In accordance with another preferred embodiment of the present invention the electrical resistance heating element is configured to define a plurality of leaves, and wherein the folding includes folding of the leaves in a generally non-overlapping arrangement. Preferably, during the folding the electrical resistance heating element is resiliently bent and folded over the forward end of the shaft and prior to and following the folding, the electrical resistance heating element extends radially outward from the shaft. 
         [0017]    In accordance with a further preferred embodiment of the present invention the hemostasis device also includes at least one peripheral balloon, disposed rearwardly of the at least one anchor balloon along the shaft and being arranged for operational interaction with tunica intima, tunica media and tunica adventitia portions of the artery and wherein the accelerating hemostasis includes allowing a limited volume of blood to collect outside of the artery in a region delimited by the engagement of the at least one peripheral balloon with the artery, following deflation of the anchor balloon and employing inflation of the at least one peripheral balloon to apply pressure to the artery to cause the tunica intima, tunica media and tunica adventitia portions on both sides of the puncture to be mutually engaged. 
         [0018]    In accordance with a still further preferred embodiment of the present invention the accelerating hemostasis also includes supplying electrical power to the electrical resistance heating element which stimulates denaturation of proteins in the tunica adventitia portion, thereby causing the tunica adventitia portion to sealingly bridge the tunica media portion at the puncture. Preferably, the accelerating hemostasis includes supplying electrical power to the electrical resistance heating element for less than 5 seconds. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which: 
           [0020]      FIGS. 1A ,  1 B,  1 C,  1 D,  1 E,  1 F,  1 G,  1 H,  1 I,  1 J and  1 K are simplified illustrations of a hemostasis device constructed and operative in accordance with another preferred embodiment of the present invention and various stages of its operation in a patient treatment context. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0021]    Reference is now made to  FIGS. 1A ,  1 B,  1 C,  1 D,  1 E,  1 F,  1 G,  1 H,  1 I,  1 J and  1 K, which are simplified illustrations of a hemostasis device constructed and operative in accordance with still another preferred embodiment of the present invention and various stages of its operation in a patient treatment context. 
         [0022]      FIG. 1A  shows a hemostasis device  100  for producing hemostasis following arterial catheterization, in accordance with a preferred embodiment of the present invention. The hemostasis device  100  is suitable for insertion via a conventional catheter introducer (not shown) following completion of catheterization and removal of the catheter from the catheter introducer. 
         [0023]    In accordance with a preferred embodiment of the present invention, hemostasis device  100  comprises a main shaft  102 , which has first and second lumens  104  and  106 . First lumen  104  extends along the main shaft  102  to an anchor balloon inflation location  112 . Second lumen  106  extends along the shaft  102  to a peripheral balloon inflation location  122 . 
         [0024]    Disposed at an end of main shaft  102  at anchor balloon inflation location  112  is an anchor element such as an anchor balloon  140 . Anchor balloon  140  is selectably inflated via a stopcock  142  and associated conduit  144  in fluid communication with first lumen  104  in main shaft  102  formed in head element  150 . Head element  150  is fixed to main shaft  102  at an end thereof opposite the end at which anchor balloon  140  is located. 
         [0025]    Disposed adjacent the end of main shaft  102  in fluid communication with peripheral balloon inflation location  122 , exterior of an outer wall  152  thereof, is a peripheral balloon  160 . Peripheral balloon  160  is selectably inflated via second lumen  106 , via a stopcock  162  and associated conduit  164  formed in head element  150 . 
         [0026]    Additionally, in accordance with a preferred embodiment of the present invention, an electrical resistance heating element  180  is disposed forwardly of the anchor balloon  140 . Preferably, the resistance heating element  180  is formed of a foil which is electrically coupled at opposite ends thereof to electrical conductors which extend through the main shaft  102 . In the illustrated embodiment, a first conductor  182  is attached to a first end  184  of resistance heating element  180  and preferably extends through the first lumen  104 , and a second conductor  186  is attached to a second end  188  of resistance heating element  180  and extends through the second lumen  106 . 
         [0027]    Preferably, the resistance heating element  180  has a generally four-leaf clover configuration, as shown, including radially extending leaves  190 , which are preferably retained in position at the end of main shaft  102  by a retaining disc  192 . Alternatively retaining disc  192  may be obviated. Electrical power is supplied to resistance heating element  180  via a switch  196 , which couples first conductor  182  and second conductor  186  to a source of electrical power. Heating of resistance heating element  180  enhances hemostasis at the aperture in the artery. 
         [0028]    Reference is now made to  FIGS. 1B-1J , which illustrate various steps in a preferred mode of operation of the apparatus of  FIG. 1A . 
         [0029]      FIG. 1B  illustrates the hemostasis device  100  about to be inserted into an artery  200  via a conventional catheter introducer assembly  202 , following completion of a catheterization procedure and withdrawal of a catheter (not shown) from the catheter introducer assembly  202 . The catheter introducer assembly  202  conventionally includes a catheter introducer sheath  204  and an entry funnel portion  205 .  FIG. 1B  also shows in cross-section, the catheter introducer sheath  204  extending through a puncture  206  in the artery  200 . It is seen that the tunica intima  208  and the tunica media  210  as well as the tunica adventitia  212  are spread apart at the puncture  206  by the presence therein of the catheter introducer sheath  204 . 
         [0030]      FIG. 1C  shows the hemostasis device  100  inserted into the catheter introducer assembly  202  such that the leaves  190  are each individually folded backwards over the end of the main shaft  102  and over balloons  140  and  160  and do not generally overlap each other. 
         [0031]      FIG. 1D  shows the hemostasis device  100  inserted through the catheter introducer assembly  202  such that the outer end of the main shaft  102  extends into the artery  200  well beyond the end of catheter introducer sheath  204 . As shown with particularity in  FIG. 1D , at this stage both anchor balloon  140  and peripheral balloon  160  are deflated. It is seen that the leaves  190  of the resistance heating element  180  have returned to their generally planar orientation, extending radially outward from main shaft  102 . 
         [0032]    Reference is now made to  FIG. 1E , which shows initial inflation of the anchor balloon  140 , preferably by use of a syringe  220 , communicating with first lumen  104  via the interior of head element  150 , stopcock  142  and associated conduit  144 . The inflated anchor balloon  140  preferably has a cusp-type configuration. 
         [0033]    Following inflation of the anchor balloon  140 , the catheter introducer assembly  202  and the hemostasis device  100  are both withdrawn, such that the catheter introducer sheath  204  is removed from artery  200  only when the anchor balloon  140  already engages the interior wall of artery  200  in sealing engagement with the aperture in the artery  200  through which the catheter introducer sheath  204  is withdrawn and through which the main shaft  102  presently extends. This stage is shown in  FIG. 1F . 
         [0034]    As seen in  FIG. 1G , initial inflation of the peripheral balloon  160  is effected, preferably by use of a syringe  240  communicating with second lumen  106  via head element  150 , stopcock  162  and associated conduit  164 . 
         [0035]    Thereafter, as seen in  FIG. 1H , the anchor balloon  140  is deflated, preferably by operation of syringe  220 , communicating with first lumen  104  via head element  150 , stopcock  142  and associated conduit  144 , and the peripheral balloon  160  remains fully inflated, which preferably causes the extreme end of the main shaft  102  to be withdrawn from the artery  200  to a location lying just outside the artery wall. As seen in  FIG. 1H , peripheral balloon  160  is preferably designed to allow a limited volume of blood to collect outside of the artery wall after the anchor balloon  140  is deflated. This volume of blood is located, in a region, indicated by reference numeral  250 , delimited by the engagement of peripheral balloon  160  with the artery wall. 
         [0036]    It is noted that at this stage, the tunica intima  208  and the tunica media  210  as well as the tunica adventitia  212  are no longer spread apart at the puncture  206 , inasmuch as the main shaft  102  is no longer present thereat and in response to pressure applied to the artery  200  by inflated peripheral balloon  160 . 
         [0037]    Preferably at this stage heating of the electrical resistance heating element  180  is effected, preferably by an operator closing switch  196 , as shown in  FIG. 1I . This heating preferably continues for less than five seconds. 
         [0038]    Once acceptable hemostasis has occurred in region  250 , the peripheral balloon  160  is deflated, as shown in  FIG. 1J , preferably by operation of syringe  240 , communicating with second lumen  106  via head element  150 , stopcock  162  and associated conduit  164 . 
         [0039]    Thereafter, the hemo stasis device  100  is entirely withdrawn from the patient, leaving a region  250  of hemostasis outside of artery  200 , as shown in  FIG. 1K . 
         [0040]    It is noted that at this stage, by virtue of denaturation of the proteins thereof, the tunica adventitia  212  sealingly bridges the tunica media at the region of the puncture  206 . Preferably, the operation of the electrical resistance heating element  180  does not produce significant heating of the tunica media and tunica intima, and does not produce heat-induced welding thereat, thus preventing the formation of lesions thereat that could otherwise occur due to excessive heating thereof. 
         [0041]    It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations and subcombinations of the various features described hereinabove and shown in the drawings as well as modifications and further developments thereof which would occur to a person of ordinary skill in the art upon reading the foregoing description and which are not in the prior art.