Abstract:
A method and device for injecting and extracting fluid at a treatment site to remove debris from the site.

Description:
CROSS REFERENCE  
       [0001]     This application is a utility case based upon provisional applications U.S. 60/402,680 filed Aug. 12, 2002; U.S. 60/316,122 filed Aug. 30, 2001; and a continuation of U.S. Ser. No. 10/231,507 filed Oct. 5, 2004 (issued as U.S. Pat. No. 6,800,075), each is incorporated by reference herein in their entirety.  
         [0002]     The application is a CIP of U.S. Ser. No. 09/637,529 filed Aug. 11, 2000; U.S. Ser. No. 09/459,225 filed Dec. 10, 1999; U.S. Ser. No. 09/995,303 filed Nov. 27, 2001; U.S. Ser. No. 10/050,978 filed Jan. 18, 2002; U.S. Ser. No. 10/145,699 filed May 14, 2002. Each is incorporated by reference herein in their entirety. 
     
    
     FIELD OF THE INVENTION  
       [0003]     The present invention relates to cardiology and more particularly to devices and methods for removing debris from vessels. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0004]     Throughout the figures like reference numerals indicate equivalent structure wherein:  
         [0005]      FIG. 1  is a schematic of the invention;  
         [0006]      FIG. 2  is a schematic of the invention;  
         [0007]      FIG. 3  is a schematic of the invention;  
         [0008]      FIG. 4  is a schematic of the invention;  
         [0009]      FIG. 5  is a schematic of the invention;  
         [0010]      FIG. 6  is a schematic of the invention;  
         [0011]      FIG. 7  is a schematic of the invention;  
         [0012]      FIG. 8  is a schematic of the invention;  
         [0013]      FIG. 9  is a schematic of the invention;  
         [0014]      FIG. 10  is a schematic of the invention;  
         [0015]      FIG. 11  is a schematic of the invention;  
         [0016]      FIG. 12  is a schematic of the invention; and,  
         [0017]      FIG. 13  is a schematic of the invention. 
     
    
     DETAILED DESCRIPTION  
       [0018]      FIG. 8  shows the overall schematic of the treatment system. A guide sheath  10  with an optional occlusion balloon  12  is navigated to the treatment site  14 . A balloon catheter  16  with a distal fluid delivery port  18  or nozzle is passed trough the guide catheter  10  to the treatment site.  
         [0019]     Fluid injected into the catheter  16  emerges from the catheter distal of the balloon  20  and induces a retrograde flow in the vessel  22 .  
         [0020]     The injected fluid may be saline, drugs or contrast agent or any biocompatible fluid. The source of fluid is selected from a conventional power injector  30  an irrigation bag suspended above the patient  32 , a conventional syringe or a Gemini syringe  34 .  
         [0021]     The guide sheath is used to extract debris from the treatment site. The outflow passes trough a valve  40 , which is associated with a switch S 1 . Preferably the valve  40  is actuated by closing S 1  and/or the manual actuation of the valve sets the switch S 1  to logic  1 . The fluid drawn from the treatment site may be collected in a manual syringe  50  the low pressure side of Gemini  34  or a vacuum container  54  or a gravity fed collection bag  52 .  
         [0022]     The balloon inflation port  60  is coupled to inflation syringe  62  and a deflation vacuum reservoir  64  through a switch valve S 2 . Inflation of the balloon proceeds normally but deflation is preferably performed in synchrony with the heart. The physician activates the physician switch PS when he wants to deflate the balloon  20 . Through logic, the valve S 2  is opened and the balloon quickly deflated at an appropriate point in the cardiac cycle.  
         [0023]     The catheter is freely movable within the sheath  10  both before during and after the procedure. That is the nozzle  18  can be “on” while the catheter is moving relative to the sheath.  
         [0024]      FIG. 1  shows a Gemini dual syringe  69  with an injection outlet  70  and an extraction or recovery inlet  72 . In this version of the device, it is attached to power injector  80 , which maybe turned on, by the switch S 3 . The plunger  74  sweeps out a volume and the displaced fluid is injected out of the port  70 . Recovered fluid from the sheath is collected at port  72 . In this fashion the volume injected and extracted are directly coupled.  
         [0025]      FIG. 2  shows a manually operated Gemini dual syringe  73  with a hand plunger  75 . This version is useful for interventions where manual control of injection is desired.  
         [0026]      FIG. 3  shows a “universal” Gemini dual syringe  77  where an additional injection ports  79  and power piston  81  drive a plunger  83 . The power inlet port  79  may couple to pump or power injector to control injection.  
         [0027]      FIG. 4  and  FIG. 5  should be considered together as depicting a method of removing debris from a vessel. In  FIG. 4 , the balloon is inflated to treat the lesion  21  in vessel  22 . A fluid injection lumen  9  in the catheter terminates in a retrograde flow-inducing nozzle  18 . At the conclusion of the intervention, the balloon is quickly deflated while fluid is injected with nozzle  18 . The retrograde flow depicted by arrow  25  sweeps debris indicated by particle  27  into the open mouth of the guide catheter  10 . It is preferred to synchronize the balloon deflation with the fluid injection at a time when the flow in the guide catheter is at a maximum and coronary flow is at a minimum. This flow in the sheath  10  out the lumen  7  is propelled by either the low pressure side of a Gemini syringe  72  or a manual syringe or a vacuum container  54  or a gravity fed bag relying on aortic pressure to force flow in the sheath  10  lumen.  
         [0028]     In the method of  FIG. 4  and  FIG. 5  The occlusion of the vessel  22  with an occlusion balloon  12  is optional and used if the flow in the guide sheath lumen  7  is too low to collect all the injected fluid and debris.  
         [0029]      FIG. 6  an  FIG. 7  show an alternate debris collection concept where fluid is injected through a guide wire lumen  90  without attempting to induce a retrograde flow. It should be appreciated that a dedicated fluid injection lumen may be used as an alternative. In  FIG. 6  an intervention takes place normally and in  FIG. 7 a  large amount of fluid is injected into the vessel distal of the lesion to displace debris toward the open mouth of the guide sheath  10 . Particles such as  27  and particle  29  are forced into the guide sheath where they are evacuated. If the flow rate of the guide sheath exceeds the injected fluid flow rate then the debris will all be sucked out without the use of an optional occlusion balloon  12 .  
         [0030]      FIG. 12  shows a QRS electrocardiograph tracing of the heart over a chart showing the time course of pressure in the aorta and flow in the coronary vessels. The optimal time to inject fluid into the coronary vessel may be when the flow in the vessels is very low  105  due to ventricular contraction. At the isovolumeic, time the aortic pressure is rising very fast  104  and this helps to promote vigorous flow in the guide sheath lumen  7  out of the body.  
         [0031]      FIG. 11  shows a system to create the trigger time signal depicted as  107  in  FIG. 12 . Conventional surface electrodes over the heart sense the cardiac depolarization and are amplified in a sense amplifier  109  this signal triggers a delay timer which may delay the activation of the remaining circuits for a few milliseconds. Depending on the overall architecture of the system any one of several approaches to controlling the system may be taken.  
         [0032]     For example  FIG. 9  assumes that a catheter structure taught by  FIGS. 6 and 7  is set up with for example a conventional injector  30  coupled to the inlet  9  and a vacuum contain attached to the outlet port  40 . In this instance, the physician signals his desire to deflate the balloon by activating the physician switch P.S. This is ANDED with the next R0-wave signal processed to give the heart signal H.S. With the and condition satisfied the logic  110  drives the switches S 1  which opens the sheath lumen  7  to the collection vessel. Essentially simultaneously, the balloon  20  is deflated by valve S 2 . At essentially the same time, the injector  30  is turned on by switch S 3 . Under these conditions, the particles  27  are displaced toward the lumen  7  by the volume of injected fluid at  9 . Of course both anntegrade flow and retrograde flow occur with the simple fluid injection but the injected volume is set to exceed the ability of the vascular bed to accept the fluid forcing particulate retrograde into the waiting lumen  7 .  
         [0033]     In  FIG. 10 a  different architecture may be employed for example a manual syringe may be connected as a fluid source for injection  9  and a collection bag  52 . In this instance the physician signal to deflate is ANDED with the heart signal H.S. and the deflation switch S 2  quickly deflates the balloon  20  while the closure of S 4  allows fluid from the syringe to enter the vessel  22  through guidewire lumen in catheter  16 . The opening of valve  40  by the closure of switch S 1  allows the collected debris and blood and injectate to flow out of the system. Once these processes are started they may terminate within one heartbeat or they may continue over several beats. In general, the closure of the fluid injection process with precedes the closure of the sheath valve  40 .  
         [0034]      FIG. 13  shows a simplified system for treating acute myocardial infarction. In these cases, the vessel is occluded by a plaque lesion, which is blocked by a clot. By pushing a catheter with a retrograde induction, nozzel  18  on it through the clot the clot is cleared and the clot debris may be collected by the sheath lumen. Again, the occlusion balloon  12  on the sheath  10  is optional. When used it is inflated just before the clot is crossed and is deflated as the nozzle  18  is retracted into the sheath  10 . Once again any fluid source and any collection vessel as depicted in  FIG. 8  may be used with this embodiment.  
         [0035]     It must be recognized that various combinations of injectors and extractors as set forth in  FIG. 8  may be arranged to carry out the invention.