Abstract:
A method for producing hemostasis of an artery of a patient having a puncture following arterial catheterization including introducing a hemostasis device including at least one electrode into the vicinity of the puncture, supplying an electric current to the at least one electrode, thereby heating blood in the vicinity of the puncture and causing coagulation of the blood and subsequently removing the hemostasis device from the patient.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 11/797,294, filed May 2, 2007, now abandoned, which is a continuation U.S. application Ser. No. 10/616,887, filed Jul. 10, 2003, now U.S. Pat. No. 7,223,266, which is a continuation-in-part of U.S. application Ser. No. 10/358,130, filed Feb. 4, 2003, now U.S. Pat. No. 7,115,127, the contents of each are incorporated by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to catheterization systems and methodologies generally and more particularly to post-catheterization closure. 
     BACKGROUND OF THE INVENTION 
     Various techniques are known for arterial catheterization. Following arterial catheterization, it is necessary to promote hemostasis quickly and without undue hardship for the patient. 
     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 simplifies hemostasis and thus greatly reduces patient discomfort following arterial catheterization. These patent documents, the disclosure 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 
     The present invention seeks to provide improved systems and methodologies for post-catheterization closure. 
     There is thus provided in accordance with a preferred embodiment of the present invention a method for producing hemostasis of an artery of a patient having a puncture following arterial catheterization including introducing a hemostasis device including at least one electrode into the vicinity of the puncture, supplying an electric current to the at least one electrode, thereby heating a volume of blood in the vicinity of the puncture, causing coagulation of the blood and causing closure of the puncture and subsequently removing the hemostasis device from the patient. 
     In accordance with another preferred embodiment of the present invention the at least one electrode includes a pair of electrodes. 
     In accordance with yet another preferred embodiment of the present invention the introducing includes introducing via a catheter introducer. Additionally, the introducing also includes inflating an anchor balloon attached to an end of the hemostasis device. Alternatively or additionally, the introducing also includes inflating a peripheral balloon. In accordance with still another preferred embodiment of the present invention the removing the hemostasis device includes deflating the peripheral balloon. 
     In accordance with another preferred embodiment of the present invention the introducing also includes positioning the at least one electrode in close proximity to the volume of blood. 
     Preferably, the supplying includes supplying electrical power at RF frequencies. Additionally, the electrical power includes electrical power in the range of 0.1-10 watts at up to 25 volts. 
     In accordance with yet another preferred embodiment of the present invention the supplying also includes adjusting the electric current based on a feedback measurement. 
     There is also provided in accordance with another preferred embodiment of the present invention a hemostasis device including a main shaft, at least one balloon and at least one electrode, operable to supply an electric current and to thereby heat a volume of blood adjacent to the at least one electrode and to cause coagulation of the blood and closure of the puncture. 
     In accordance with another preferred embodiment of the present invention the at least one balloon includes at least one anchor balloon, disposed at an end of the main shaft and at least one peripheral balloon, disposed at a location along the main shaft exterior to a wall of the main shaft. Preferably, the volume of blood is delimited by the peripheral balloon and a wall of the artery. 
     In accordance with yet another preferred embodiment of the present invention the hemostasis device also includes an electrical power source and control module. Additionally, the electrical power source and control module includes a power supply, operative to supply power to the at least one electrode, feedback measurement means and a processor. 
     Preferably, the power supply includes an RF power supply which supplies electrical power at RF frequencies within a range of 0.1-10 watts at up to 25 volts. 
     In accordance with still another preferred embodiment of the present invention the feedback measurement means is operative to measure at least one of electrical current, blood resistance and blood temperature. 
     Additionally, the processor is operative to adjust the power based on an output from the feedback measurement means. 
     In accordance with yet another preferred embodiment of the present invention the at least one electrode includes a pair of electrodes. 
     There is further provided in accordance with yet another preferred embodiment of the present invention a method for producing hemostasis of an artery of a patient having a puncture following arterial catheterization, including introducing a hemostasis device including at least one electrode into the vicinity of the puncture, positioning the at least one electrode in proximity with the puncture, supplying an electric current to the at least one electrode, thereby heating a volume of blood in the vicinity of the puncture, causing coagulation of the blood and causing closure of the puncture and subsequently removing the hemostasis device from the patient. 
     In accordance with another preferred embodiment of the present invention the positioning includes inflating an anchor balloon attached to an end of the hemostasis device, inflating a peripheral balloon and subsequently deflating the anchor balloon. Preferably, the volume of blood is delimited by the peripheral balloon and a wall of the artery. 
     In accordance with still another preferred embodiment of the present invention the at least one electrode includes a pair of electrodes. 
     In accordance with yet another preferred embodiment of the present invention the supplying includes supplying electrical power at RF frequencies. Additionally, the electrical power includes electrical power in the range of 0.1-10 watts at up to 25 volts. 
     In accordance with another preferred embodiment of the present invention the supplying also includes adjusting the electric power based on a feedback measurement. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which: 
         FIG. 1  is a simplified illustration of a hemostasis device constructed and operative in accordance with a preferred embodiment of the present invention; 
         FIGS. 2A ,  2 B,  2 C,  2 D,  2 E,  2 F,  2 G,  2 H and  2 I are simplified illustrations of the operation of the apparatus of  FIG. 1  in a patient treatment context; and 
         FIG. 3  is a simplified illustration of a hemostasis device constructed and operative in accordance with another preferred embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Reference is now made to  FIG. 1 , which is a simplified illustration of 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. 
     In accordance with a preferred embodiment of the present invention, hemostasis device  100  comprises a main shaft  102 , which has an outer wall  104  and preferably includes at least three bores. A first bore, designated generally by reference numeral  110 , extends along the main shaft  102  to an anchor balloon inflation location  112 . A second bore  120  extends along the shaft  102  to a peripheral balloon inflation location  122 . A third bore, designated generally by reference number  130 , contains an electrocoagulation heating device  132  connected to an electrical power source and control module  134  by a connector  136 . 
     Disposed at an end of main shaft  102  at anchor balloon inflation location  112  is an anchor balloon  140 . Anchor balloon  140  is selectably inflated, as shown in  FIG. 2C , via a stopcock  142  and associated conduit  144  in fluid communication with main shaft  102  via a 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. The interior of head element  150  is in fluid communication with first bore  110  in main shaft  102 , which in turn is in fluid communication with the interior of the anchor balloon  140  at anchor balloon inflation location  112 . 
     Disposed adjacent the end of second bore  120  in fluid communication with peripheral balloon inflation location  122 , exterior of wall  104 , is a peripheral balloon  160 . Peripheral balloon  160  is selectably inflated, as shown in  FIG. 2E , via second bore  120 , via a stopcock  162  and associated conduit  164  that communicate with second bore  120  via head element  150 . 
     In accordance with a preferred embodiment of the present invention, electrocoagulation heating device  132  comprises an electrical conductor  170  connected to an electrocoagulation electrode  176  at an extreme end  178  of third bore  130 . A pair of electrical cables  180  and  182  extend from electrical power source and control module  134 . In the illustrated embodiment, electrical cable  180  serves as a power supply cable and is connected to electrocoagulation heating device  132  by connector  136 . Electrical cable  182  serves as a return current cable and is preferably connected to an electrode  184  attached to a body of a patient. 
     Electrical power source and control module  134  preferably comprises a power supply, preferably an RF power supply source  186 , including a feedback measurement circuit  188 . The feedback measurement circuit  188  is preferably operative to measure current, blood resistance or blood temperature and thereby determine progress of hemostasis. The electrical power source and control module  134  also preferably includes a microprocessor  190 , operative to adjust the power supplied to hemostasis device  100  according to the blood temperature or other feedback measurement received from feedback measurement circuit  188 , in order to achieve optimal coagulation of the blood. 
     In accordance with a preferred embodiment of the present invention an operator actuation switch  192  is connected along electrical cable  180 . In accordance with another preferred embodiment, switch  192  may be obviated and electrical cable  180  connected directly to connector  136 . 
     Reference is now made to  FIGS. 2A-2I , which illustrate various steps in a preferred mode of operation of the apparatus of  FIG. 1 . 
       FIG. 2A  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 . 
       FIG. 23  shows the hemostasis device  100  inserted into 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. 2B , at this stage both anchor balloon  140  and peripheral balloon  160  are deflated. 
     Reference is now made to  FIG. 2C , which shows initial inflation of the anchor balloon  140 , preferably by use of a syringe  220  communicating with first bore  110  via the interior of head element  150 , stopcock  142  and associated conduit  144 . The inflated anchor balloon  140  preferably has a cusp-type configuration as seen with particularity in  FIG. 2C . 
     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 drawn and through which the main shaft  102  presently extends. This stage is shown in  FIG. 2D . 
     As seen in  FIG. 2E , initial inflation of the peripheral balloon  160  is effected, preferably by use of a syringe  240  communicating with second bore  120  via head element  150 , stopcock  162  and associated conduit  164 . 
     Thereafter, as seen in  FIG. 2F , the anchor balloon  140  is deflated and the peripheral balloon  160  is more 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. 2F , 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. 
     At this stage, electric power is supplied to the electrode  176  to provide heating of the blood in region  250 , causing coagulation thereof, as seen in  FIG. 2G . In accordance with the illustrated embodiment of  FIG. 1  and as shown in  FIG. 2G , the electric power is provided by actuation of switch  192 . In accordance with another preferred embodiment, switch  192  is obviated, and the electric power is provided by connecting electrical cable  180  ( FIG. 1 ) directly to connector  136 . 
     Preferably, the amount of electrical power supplied along electrical cable  180  ( FIG. 1 ) from electrical power source and control module  134  to the electrocoagulation electrode  176  is between 0.1-10 watts at up to 25 volts at RF frequencies. 
     Once acceptable hemostasis has occurred in region  250 , the peripheral balloon  160  is deflated, as shown in  FIG. 2H , preferably by operation of syringe  240  communicating with second bore  120  via head element  150 , stopcock  162  and associated conduit  164 . 
     Thereafter, the hemostasis device  100  is entirely withdrawn from the patient, leaving a region  260  of hemostasis outside of artery  200 , as shown in  FIG. 2I . 
     Reference is now made to  FIG. 3 , which is a simplified illustration of a hemostasis device constructed and operative in accordance with another preferred embodiment of the present invention. The embodiment of  FIG. 3  is similar to that of  FIG. 1 , except as described hereinbelow. Elements that occur in both embodiments are identified by the same reference numerals. 
     In the embodiment of  FIG. 3 , electrocoagulation heating device  132  comprises a pair of separate electrical conductors  300  extending along third bore  130  connecting electrical power source and control module  134  to a pair of electrocoagulation electrodes  302  at end  178  of third bore  130 . Electrical cables  180  and  182  are both connected to electrocoagulation heating device  132  by connector  136 . The illustrated embodiment shows connector  136  directly connected to electrical cables  180  and  182 . 
     In the embodiment of  FIG. 3 , the electrodes  302  may be arranged in mutual coaxial arrangement or in mutual side-by-side arrangement or any other suitable arrangement. 
     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.