Rheolytic thrombectomy catheter with self-inflating proximal balloon with drug infusion capabilities

A thrombectomy catheter with a self-inflating proximal balloon having drug infusion capabilities is described. A self-inflating balloon is formed from an inflatable thin walled section of a flexible catheter tube. The self-inflating balloon includes a plurality of outflow orifices located about the peripheral circumference thereof and located proximal to an inflow gap interposed between a fluid jet emanator and the self-inflating balloon. The self-inflating balloon is inflated and expanded by internal operating pressures by proximal composite flow of fluid from the fluid jet emanator and entrained fluid from the inflow gap to uniformly space and position the outflow orifices of the self-inflating balloon in close proximity to the thrombus or vessel walls of a blood vessel. The thrombectomy catheter may be used for, among other things, thrombectomies, embolectomies, thrombus or vessel dilation, and for the delivery of drugs to a thrombus or vessel site.

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

The present disclosure relates to a thrombectomy catheter, but more specifically relates to a rheolytic thrombectomy catheter with a self-inflating proximal balloon having drug infusion capabilities and, for purposes of brevity, is alternately referred to herein as a rheolytic thrombectomy catheter. The terms used herein are not intended to be limited to any particular narrow interpretation unless clearly stated otherwise in this document.

2. Description of the Prior Art

Prior art and its comparison to the devices of the present disclosure are partially set forth herein. Flow cessation of prior art devices to minimize hemolysis and for other reasons has been accomplished via a balloon on a proximally placed guide catheter or by way of proprietary occlusion guidewire technology, such as, but not limited to, the use of balloons on guidewires. With respect to thrombectomy performance, prior art cross stream jet catheter designs have been described in prior patents by the present inventors or assignees. Such prior art cross stream jet catheter designs use cross stream jets flowing between outflow orifices and inflow orifices located on an exhaust tube to impinge, macerate and carry thrombus debris away from a thrombus site and through the exhaust tube. In the present disclosure, as opposed to prior art thrombectomy catheters which place outflow orifices in the exhaust tube, outflow orifices are positioned on the periphery of a self-inflated balloon to provide significantly more effective thrombus removal. For example, a peripheral cross stream jet thrombectomy catheter exhaust tube may have the diameter of 2 mm (6 Fr) and may be treating an 8 mm blood vessel. Cross stream jets flowing outwardly from the side outflow orifices are used to liberate debris such that the thrombus may be evacuated by the inflow orifices. Ideally, these side exhaust jets would typically travel outwardly at an average of 3 mm to impinge and scrub thrombus deposits on a vessel wall. If the peripheral cross stream jet thrombectomy catheter exhaust tube is off center, which is the norm, the outwardly directed side outflow cross stream jets could travel up to 6 mm to impinge and scrub thrombus on a vessel wall. The side outflow orifices are typically less than 0.66 mm in diameter and as a result the cross stream jet may travel almost 10 diameters to impinge the vessel wall. As a cross stream jet travels, the surrounding fluid slows the cross stream jet, hence, the ability to remove debris is diminished. Compare the prior scenario to the devices of the present disclosure in which the outflow orifices are located on the periphery of a self-inflating balloon. The self-inflating balloon size and catheter are selected by the physician to match the treated vessel size in order that the balloon will always inflate to attempt to be in direct contact with the thrombus. Hence, the cross stream jets will travel a very short distance (i.e., less than 10 diameters) substantially unimpeded by surrounding fluids to impinge the thrombus with maximum velocity. Secondly, inflation of the self-inflating balloon ensures centering of the device so that the vessel is treated equally in all circumferential directions. This design enables a more effective and greater removal of tougher and more organized thrombus. Furthermore, it enables a greater and more uniform delivery of drugs into this tougher mural thrombus.

Vessel safety is improved and enhanced by use of devices of the present disclosure. In previous cross flow design thrombectomy catheters, vessel damage is primarily inflicted when the vessel wall is sucked in by the negative pressures at the inflow orifices to the point that the internal high velocity jet streams can damage the vessel wall. In fact, merely moving the catheter while the inflow orifices have been sucked onto the vessel wall is a likely mechanism for vessel damage from cross stream catheters. Vessel damage increases with the size of the inflow orifices and with the proximity of the high velocity fluid jet stream origin to the inlet orifice. In the case of devices of the present disclosure, an inlet gap (inlet orifice) is positionally located away from the vessel wall by the centering action of the self-inflating balloon.

SUMMARY OF THE DISCLOSURE

The general purpose of the present disclosure is to provide a rheolytic thrombectomy catheter sold under the trademark AngioJet®, to elegantly stop and/or impede blood flow in a vessel while simultaneously increasing the efficacy of thrombus removal. Flow cessation optimizes the effectiveness of thrombectomies, embolization containment, and procedures involving drug infusion, as well as minimizing hemolysis. Other issues addressed by the use of devices of the present disclosure relate to catheter centering, thrombus and/or vessel dilation or a modified embolectomy.

The main structure and feature of devices of the present disclosure involves the use of a proximally placed self-inflating balloon integral to and formed from a thin wall section of the exhaust tube of the rheolytic thrombectomy catheter which is inflatingly deployed using the back pressure created by the operation of the high velocity fluid jet streams used in a thrombectomy catheter, such as an AngioJet® catheter. The self-inflating balloon has a plurality of outflow orifices located about its peripheral circumference. Inflation of the balloon places the outflow orifices in close proximity to the thrombus buildup on a vessel wall. High velocity fluid jet streams emitted from an emanator exit these outflow orifices as uniformly distributed cross stream jets and return through an inflow gap, substantially a large inflow orifice, the function of which is closely related to that of multiple inflow orifices.

The device is a rheolytic enhanced thrombectomy catheter and can be used for removal of thrombus in coronary arteries, peripheral arteries or veins, neurological arteries or veins, or arterial venous conduits. By sizing the balloon for the intended vessel, the expanded balloon with peripheral circumference outflow orifices will be more efficacious in removing more organized clots. The blockage of blood flow by the inflated balloon also minimizes hemolysis. Hemolysis formed from a stagnant blood field is dramatically less than that of a flowing blood field. The self-inflating balloon of the present disclosure can also be used to dilate a vascular obstruction or narrowing.

The present disclosure describes the addition of a self-inflating balloon with outflow orifices or perforations to any of the AngioJet® catheter models. The self-inflating balloon is proximally located with respect to a high velocity fluid jet stream emanator. Although balloons attached to catheters proximally or distally have been suggested in the past, this concept goes one step further by creating a self-inflating balloon out of the distal exhaust tube (Pebax® material or polyurethane, etc.) while using the exhaust pressure of the high velocity fluid jet streams to fill and sustain the self-inflating balloon for purposes of proximal protection or occlusion (and in some cases when the rheolytic thrombectomy catheter is used in an anti-grade flow, distal protection). Furthermore, the self-inflating balloon includes a plurality of outflow orifices about its peripheral circumference so that when the self-inflating balloon is inflated, the fluid outflow in the form of cross stream jets is closely and intimately directed against the thrombus. In essence, the devices of the present disclosure provide a cross stream rheolytic thrombectomy catheter where the outflow orifices are in close or intimate proximity to the vessel wall and/or thrombus. This arrangement minimizes profile, minimizes the number of components and design complexity, minimizes manufacturing costs, and is very easy to use since the self-inflating balloon is deployed automatically when the rheolytic thrombectomy catheter is activated.

Since AngioJet® catheters remove debris more effectively in a stagnant flow, this device has several applications. It could be used with a filter to more effectively remove debris from within and around the filter. Furthermore, bench testing has shown that devices of the present disclosure are substantially more efficacious at clot removal than conventional AngioJet® catheters due to a cross stream jet configuration featuring a large inflow gap (inlet orifice). Cessation of flow and the large “pocket” the self-inflating balloon creates can ultimately increase the recirculated flow rate. Devices of the present disclosure can be used just to increase the amount of debris/thrombus removed from a particular vessel length. With this in mind, it should also minimize any distal or proximal embolization. It could also be used to deliver drugs more effectively in a stagnant field. The outflow orifices in the self-inflating balloon can drive the drugs deeper into the thrombus or even treat or lavage a vessel wall. The self-inflating balloon could also be used for centering or positioning the catheter in a vessel to minimize vessel damage as described above. Hence, the inlet orifice structure, herein referred to as an inflow gap, for the rheolytic thrombectomy catheter is enlarged to enable maceration of larger and tougher embolic debris. The self-inflating balloon could slightly dilate an occluded section, an obstruction, or a narrowed area due to the pressurized outwardly directed self-inflating balloon structure, thereby providing automatic angioplasty along with debris removal. Finally, the self-inflating balloon could be used to break up clots as it is moved through a blocked vessel, thereby performing a modified embolectomy.

According to one or more embodiments of the present disclosure, there is provided a rheolytic thrombectomy catheter including a manifold, a catheter tube connected to and extending distally from the manifold, a distally located tapered flexible tip spaced distally from the distal end of the catheter tube to form an inflow gap therebetween, a tubular shaped emanator secured at the proximal end of the tapered flexible tip by the use of a marker band, a distally located thin section of the catheter tube comprising a self-inflating balloon having a plurality of outflow orifices about the peripheral circumference thereof, marker bands secured over and about the catheter tube on each end of the self-inflating balloon, and a high pressure tube extending through portions of the manifold, through the catheter tube and self-inflating balloon, and through marker bands and extending further across the inflow gap to communicatingly terminate within the emanator.

Multiple significant aspects and features of a rheolytic thrombectomy catheter incorporate and exemplify many of the features and teachings and include enhancements thereof of a rheolytic thrombectomy catheter sold under the trademark AngioJet®.

One significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon with outflow orifices, which is created from the exhaust tube itself.

One significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon with outflow orifices, which balloon is deployed by the back pressure created during operation of devices of the present disclosure.

One significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon with outflow orifices, which balloon is fixed and positioned between two marker bands with an underlying stabilizing saddle or by another suitable means.

One significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon with outflow orifices, which balloon is used for the purpose of impeding fluid flow in a blood vessel or other conduit.

One significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon with orifices, which balloon is used for the purpose of cessation of fluid flow in a blood vessel or other conduit in order to maximize the effect of a thrombectomy catheter in terms of debris or tissue removal.

Another significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon which is used for the purpose of cessation of fluid flow in a blood vessel or other conduit in order to maximize the effect of a thrombectomy catheter in terms of debris or tissue removal from a distal protection filter wire or a balloon.

One significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon used for the purpose of centering the catheter.

One significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon used for the purpose of a modified embolectomy.

One significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon used for the purpose of dilating a vessel or an occlusion.

One significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon used for the purpose of minimizing hemolysis.

One significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon used for the purpose of infusing drugs on a vessel wall or into a thrombus.

One significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon with outflow orifices used with an inflow gap for removing debris.

One significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon with outflow orifices used with one or more inflow orifices for removing debris.

Another significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon with outflow orifices used with an inflow gap or one or more inflow orifices for removing debris and used with additional radially directed spray jets emanating from a jet body loop.

Still another significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon having a diameter which could range from 2-20 mm.

Still another significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon which could range from 2-200 mm in length.

Still another significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon which could be compliant, semi-compliant, or noncompliant in nature.

Still another significant aspect and feature of devices of the present disclosure is a self-inflating proximal balloon having an internal operating pressure up to 20 ATM.

Having thus briefly described one or more embodiments of the present disclosure and having mentioned some significant aspects and features of devices of the present disclosure, it is the principal object of the present disclosure to provide a rheolytic thrombectomy catheter with a self-inflating proximal balloon with drug infusion capabilities.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1is a plan view of the visible components of a rheolytic thrombectomy catheter10. The device includes a one-piece manifold12having multiple structures extending therefrom or attached thereto, and also includes a flexible catheter tube14and other components associated therewith as described herein. The visible portion of one-piece manifold12includes a central tubular body16, a threaded exhaust branch18, and a high pressure connection branch20extending angularly from central tubular body16, a partially shown cavity body22extending proximally from central tubular body16and a threaded connection port24extending distally from central tubular body16. The proximal end of catheter tube14is secured to manifold12by the use of a Luer fitting26accommodated by threaded connection port24. The proximal end of catheter tube14extends through a strain relief tube28and through Luer fitting26to communicate with manifold12. Also shown is a hemostasis nut30aligned with and threadingly engaged with the proximal region of cavity body22. A threaded high pressure connection port32is secured to high pressure connection branch20by a Luer connector34. An introducer36is also shown.

Catheter tube14extends distally to spacingly terminate a short distance from a tapered flexible tip38and a fluid jet emanator52, not shown inFIG. 1but shown inFIGS. 4 and 5, to provide an annular inflow gap40. A distal section of catheter tube14includes a self-inflating balloon42(shown inflated by dashed lines42a) proximal to inflow gap40. A plurality of outflow orifices44a-44nwhich can be arranged in various patterns is distributed about the central outer circumference of self-inflating balloon42for the disbursement of cross stream jets therefrom when the balloon is inflated. Catheter tube14functions as an exhaust tube for the evacuation of macerated effluence from the site of a thrombus or lesion. Preferably, catheter tube14includes a hydrophilic coating to enhance deliverability along the vasculature or other structure. Catheter tube14is made from a flexible plastic material or another suitable flexible material.

FIG. 2is an isometric exploded and segmented view of rheolytic thrombectomy catheter10andFIG. 3is an assembled view, in partial cross section, of the components of manifold12and closely associated components and features thereof.

A collection of assembled components including a high pressure tube50and a fluid jet emanator52deliver a high pressure saline or other suitable fluid to the distal portion of catheter tube14for creation of high velocity jet streams which are directed proximally from fluid jet emanator52and which flow as exterior cross stream jets from the plurality of outflow orifices44a-44nlocated at the peripheral circumference of self-inflating balloon42and return into inflow gap40, as later described in detail. High pressure tube50, preferably of flexible stainless steel or other suitable material, passes through and is generally distal to strain relief tube28and extends along a greater portion of and within a lumen of catheter tube14to terminate at fluid jet emanator52. The distal end of high pressure tube50, including fluid jet emanator52, is also shown in greater detail inFIGS. 4 and 5.

With reference toFIGS. 2 and 3, the devices of the present disclosure are further described. Manifold12includes connected and communicating passageways and cavities (FIG. 3) including a high pressure connection branch passageway54, an exhaust branch passageway56, a tapered central passageway58extending from and through threaded connection port24and through central tubular body16to and communicating with a multiple radius cavity60, which preferably is cylindrical and located central to cavity body22. External threads62are located about the proximal portion of cavity body22at the proximal region of manifold12for accommodation of internal threads64of hemostasis nut30.

The devices of the present disclosure benefit from the use of a flexible self-sealing hemostasis valve66, and the use of a washer68which is located distal to self-sealing hemostasis valve66, the shapes and functions of which are described in the referenced U.S. Pat. No. 7,226,433. Self-sealing hemostasis valve66and washer68are aligned in and housed in the greater radius portion of multiple radius cavity60of cavity body22. Hemostasis nut30includes a centrally located cylindrical boss70. Washer68and self-sealing hemostasis valve66are captured within the greater radius portion of multiple radius cavity60by threaded engagement of hemostasis nut30to threads62at the proximal end of manifold12. Cylindrical boss70is brought to bear against the collective self-sealing hemostasis valve66and washer68to resultingly bring pressure to bear, as required, against self-sealing hemostasis valve66, which pressure culminates in a forcible sealing of self-sealing hemostasis valve66about guidewire46. Although one method of sealing against a guidewire is briefly shown and described, it is appreciated that other methods can be incorporated into this and other forms of the devices of the present disclosure such as those referenced in U.S. Pat. No. 7,226,433.

Also shown is a ferrule76which is aligned within a passageway78of threaded high pressure connection port32, the combination of which is partially aligned within an interior passageway80of Luer connector34. The proximal end of flexible high pressure tube50, shown in segmented form inFIG. 2, can be utilized for the delivery of high pressure ablation liquids or for the delivery of drugs or other liquids and is suitably secured in a central passageway of ferrule76to communicate with interior passageway78of threaded high pressure connection port32, as shown inFIG. 3. The proximal end of high pressure tube50also extends through high pressure connection branch passageway54, through part of tapered central passageway58, through strain relief tube28and Luer fitting26, and through a lumen82of catheter tube14.

High pressure tube50extends through support rings84and86and is suitably connected thereto, as shown inFIG. 4, to provide an anchoring and alignment structure for high pressure tube50in affixing the distal portion of high pressure tube50within the distal region of catheter tube14. In addition, high pressure tube50also extends through radiopaque marker bands88and90. High pressure tube50preferably is attached to support rings84and86, such as by welding or other suitable means, where support rings84and86function as co-located supports for catheter tube14in the region beneath radiopaque marker bands88and90. A short distal section of high pressure tube50extends across inflow gap40and terminates within an internal annular manifold (not shown) of fluid jet emanator52, which is suitably attached thereto where fluid jet emanator52communicates with the lumen of high pressure tube50, such as to a closely related fluid jet emanator described in the previously referenced patent application Ser. No. 11/096,592 or other applications or patents assigned to the assignee. Fluid jet emanator52, also shown inFIG. 5as an isometric view, includes an annular groove94which is in coordination use with a radiopaque marker band92to secure tapered flexible tip38about fluid jet emanator52. InFIG. 2, radiopaque marker bands88and90are shown displaced a short distance distal to support rings84and86and fluid jet emanator52is shown displaced proximally a short distance from radiopaque marker band92for the purpose of clarity and are shown in frictional engagement in their actual position along and with respect to the distal portion of catheter tube14inFIG. 4.

The relationships of radiopaque marker bands88,90and92, support rings84and86, and fluid jet emanator52, respectively, to each other and to catheter tube14are shown best inFIG. 4. InFIG. 4, self-inflating balloon42is shown contiguous with catheter tube14, wherein self-inflating balloon42has a reduced wall thickness14awhen compared to the general wall thickness of catheter tube14. The reduced wall thickness14aof self-inflating balloon42is of a suitable thickness in order to allow the inflation of self-inflating balloon42to thereby expand, meet and align against the wall of the vasculature or against the thrombus, whereby a thrombectomy procedure, drug delivery procedure or other procedure can take place. For the purpose of demonstration and illustration, self-inflating balloon42can range in length from 2 mm to 200 mm. When self-inflating balloon42is in the inflated state, as represented by inflated balloon42a, the central diameter of self-inflating balloon42can range from 2 mm to 20 mm. Inflated balloon42acan be expanded, as desired, with an internal pressure up to 20 ATM. Radiopaque marker bands88and90and support rings84and86are shown forcibly contacting the full wall thickness of catheter tube14adjacent the ends of self-inflating balloon42, thereby allowing substantially the full length of reduced wall thickness14aof self-inflating balloon42to be utilized for expansion. Expansion of self-inflating balloon42is shown in dashed lines by inflated balloon42a. Alternatively, reduced wall thickness14aof self-inflating balloon40can be formed from other materials, as known in the art, and then bonded or extruded to catheter tube14to maintain a continuous structure throughout the length of catheter tube14.

In all embodiments of the present disclosure outflow orifices44a-ncan have any of a number of different configurations. For example, spiral or slotted cuts can be formed that extend from one end of the periphery of self-inflating balloon42to the other. Alternatively as few as two outflow orifices may be utilized to effectuate the delivery of fluid for thrombectomies or other procedures as described herein. Still other patterns and numbers of outflow orifices can also be utilized on all sections of the periphery of self-inflating balloon42without departing from the scope of the present disclosure.

Tapered flexible tip38is shown including a multiple radius inner passageway96for the accommodation of fluid jet emanator52and a guidewire46(not shown inFIG. 4). The distally located radiopaque marker band92is forcibly applied around the external proximal portion of tapered flexible tip38to cause a frictional annular engagement of the proximal portion of tapered flexible tip38with all or part of an annular groove94of fluid jet emanator52. Such frictional engagement is sufficient to place the outer radial surface of radiopaque marker band92(also88and90) in a position lesser than the general and greater outer radial surface of catheter tube14, thereby providing, in part, a catheter tube14having no elements protruding beyond the general outer radial surface thereof for an unimpeded and smooth distal or proximal transition of catheter tube14within a vein, artery or the like. A passageway98(FIG. 5) is shown central to fluid jet emanator52to accommodate the passage of a guidewire.

Structure is provided to nurture and aid the introduction of and passage of the distal portion of catheter tube14through blood vessels, arteries and the like to the sites of thrombotic deposits or lesions. Tapered flexible tip38, as opposed to a rounded and nontapered flexible tip, can part and more easily penetrate thrombotic deposits or lesions during its insertional travel in a distal direction instead of advancing or pushing such thrombotic deposits or lesions distally. The decreasing diameter in a distal direction of tapered flexible tip38also allows for an increased flexibility in negotiating and passing through tortuous paths.

Exhaust tube support rings84and86in use with radiopaque marker bands88and90in the regions surrounding the opposed ends of self-inflating balloon42are examples of structures offering support or reinforcement along catheter tube14in the regions adjacent to the ends of self-inflating balloon42. Such support rings allow the use of a thinner wall thickness for catheter tube14in order to allow for a larger and more effective and efficiently sized lumen82, as well as contributing to a reduced sized outer diameter. Such support rings also contribute to supportively maintain the diameter and overall shape of catheter tube14when catheter tube14is pushed or advanced along a vein or vessel, as well as aiding in torsional support.

FIG. 5is an isometric view of fluid jet emanator52shown connected to and in communication with high pressure tube50. Fluid jet emanator52includes a plurality of rearwardly aligned orifices112a-112nparalleling the longitudinal axis of fluid jet emanator52, as well as including the previously described annular groove94and passageway98. Fluid jet emanator52delivers a high pressure saline or other suitable fluid to the distal portion of catheter tube14for the creation of high velocity jet streams114which are directed proximally from orifices112a-112nof fluid jet emanator52and thence within the confines of self-inflating balloon42to contribute in the formation of inflated balloon42aand to perform other functions as described herein. Although the use of the particular style of fluid jet emanator52is shown, other fluid jet emanators having other configurations, such as those disclosed in U.S. Pat. Nos. 5,370,609 and 6,676,637, both of which are incorporated herein by reference, can also be utilized with the devices of the present disclosure, along with other designs and securitization methods described in the literature by the assignee of the present disclosure. Each separate design of fluid jet emanator52works similarly in that they emanate high velocity jet streams114and can be used in lieu of the specific fluid jet emanator52herein disclosed; the use of other fluid jet emanators shall not be considered to be limiting to the scope of the present disclosure.

Mode of Operation

Generally, a normal guidewire is deployed in a vessel requiring treatment or, in the alternative, a filter guidewire or balloon occlusion guidewire could also be used. Distally located components of rheolytic thrombectomy catheter10consisting mainly of catheter tube14, high pressure tube50, fluid jet emanator52, and other components directly associated therewith, are advanced over and/or along a guidewire previously positioned in the vasculature for the purpose of debris/thrombus removal, drug infusion or other procedures and maneuvered into the appropriate position for treatment. A guide catheter or sheath can be incorporated as necessary to offer assistance in placing catheter tube14of rheolytic thrombectomy catheter10within the desired location of the vasculature. Rheolytic thrombectomy catheter10is then activated, wherein self-inflating balloon42is automatically and expandingly deployed reforming as an expanded balloon42a, and then thrombus, debris and the like are removed or drugs can be infused by a desired procedure. Self-inflating balloon42can be alternately pressurized and depressurized, wherein rheolytic thrombectomy catheter10may be moved proximally or distally during the procedure to maximize the effect of the system. When the procedure is complete, self-inflating balloon42is generally deflated sufficiently under normal arterial pressure to be removed safely, or deflation can be aided with a manual syringe attached to an effluent line, or deflation can be aided by means of a roller pump. Further interventions can be executed as normal over the remaining guidewire or guidewire device.

More specifically,FIGS. 6 and 7illustrate the mode of operation, whereFIG. 6illustrates the embodiment connected to ancillary devices, andFIG. 7illustrates the distal portion of rheolytic thrombectomy catheter10in the performance of the method and use of devices of the present disclosure. The mode of operation is best understood by referring toFIGS. 6 and 7, along with the previously described figures.

InFIG. 6, rheolytic thrombectomy catheter10is shown engaged over and about a guidewire46, wherein guidewire46(previously inserted into a vein or artery) first slidably passes through passageway96of tapered flexible tip38followed by transiting passageway98of fluid jet emanator52, inflow gap40, the distal end of lumen82at the distal end of catheter tube14, self-inflating balloon42, lumen82of catheter tube14proximal to inflow gap40, strain relief tube28, tapered central passageway58, slidable within and in sealed engagement with hemostasis valve66and to finally exit from hemostasis nut30. A high pressure fluid source100and a high pressure fluid pump102are connected to the manifold12via the threaded high pressure connection port32and connector104. The fluid source may consist of saline, one or more drugs for attacking the thrombus, or a mixture of saline and one or more drugs and the fluid source can be changed dynamically while catheter tube14remains in the patient. An exhaust regulator106, such as a roller pump or other suitable device, and a collection chamber108are connected to the threaded exhaust branch18by a connector110, as shown.

FIG. 7is a side view in partial cross section of rheolytic thrombectomy catheter10in the performance of the method and use thereof with particular attention given to the distal portion of catheter tube14, flexible tapered tip38, fluid jet emanator52, inflow gap40, inflated balloon42a, and other closely associated components positioned in a blood vessel116at a site of a thrombotic deposit or lesion118. Multiple high velocity fluid jet streams114of saline, for example, or other suitable fluid, are shown being emitted in a proximal direction from jet orifices112a-112nof fluid jet emanator52in order to assist in the inflation of self-inflating balloon42for the purposes of, but not limited to, impeding fluid flow to effect a stagnate flow in the thrombectomy region, to provide centering of inflated balloon42a, and to ultimately accomplish thrombectomy or drug delivery functions as described herein. Use of devices of the present disclosure can also provide for the performance of a modified embolectomy by breaking up clots as inflated balloon42ais moved through a blocked vessel, dilating a vessel or an occlusion with inflated balloon42a, infusing drugs on a vessel wall or into a thrombus by the use of inflated balloon42aand outflow orifices44a-nor to minimize any distal or proximal embolization. Self-inflating balloon42is pressurized by utilizing back pressure along catheter tube14in conjunction with the pressure of high velocity fluid jet streams114and is automatically and expandingly deployed reforming as an inflated balloon42aby means of pressurized high velocity fluid jet streams114. Inflated balloon42acan be compliant, semi-compliant, or noncompliant according to the procedure performed. Exhaust regulator106is used to influence the degree of inflation of expanded balloon42a, as well as to influence the outgoing fluidic macerated debris through catheter tube14. Fluid jet emanator52or other fluid jet emanators of appropriate size and/or configuration can be incorporated within the proximal section of tapered flexible tip38as an alternative to emanate or emit one or more high velocity fluid jet streams114proximally along or near the longitudinal axis of catheter tube14.

The positioning of the peripheral circumference of inflated balloon42aaligns outflow orifices44a-44nin close proximity to or against either the thrombotic deposit or lesion118, or as generally shown inFIG. 7, in close proximity to or against the wall of blood vessel116in order to effect fluid flow reduction or cessation. Inflated balloon42asubstantially provides uniform centering and positioning of outflow orifices44a-44nwith respect to the surrounding thrombotic deposit or lesion118and/or blood vessel116, thereby providing equally powered passage and distribution of high velocity fluid jet streams114outwardly from outflow orifices44a-44nas cross stream jets120. High velocity fluid jet streams114of saline pass outwardly through outflow orifices44a-44ncreating cross stream jets120(lower velocity jets) directed outwardly toward and for immediate contact first with the thrombotic deposit or lesion118, if present, and thence with the wall of blood vessel116. Cross stream jets120are influenced by the low pressure at inflow gap40to cause cross stream jets120to flow circumferentially and distally to impinge on, provide drag forces on, and break up thrombotic deposits or lesions118, and to, by entrainment, urge and carry along one or more particles118aof thrombotic deposits or lesions118through inflow gap40, a relatively low pressure region, into high velocity fluid jet streams114where thrombus particles118aare further macerated into microscopic particles, and then urged along lumen82of catheter tube14by the action of high velocity fluid jet streams114. A certain portion of this macerated thrombus debris is mixed with the fresh saline high velocity fluid jet stream114and forcibly removed through lumen82of catheter tube14and a certain portion of this macerated thrombus flows back out outflow orifices44a-44nand recirculates to break up more thrombus debris which is returned to inflow gap40. In this way, much more fluid flow circulates, or recirculates, through the system, than is injected through jet orifices112a-112n. For purposes of illustration and example, three to ten times more fluid flow circulates through the system than is delivered by jet orifices112a-112n. The entrainment of thrombus or debris through inflow gap40is based on entrainment by high velocity fluid jet streams114. The outflow of fluid and thrombus is driven proximally through catheter tube14by an internal pressure which is created by high velocity fluid jet streams114and the fluid entrained through inflow gap40. An enhanced clot removal is attainable because of the recirculation pattern established between outflow orifices44a-44nand inflow gap40, which creates a flow field that maximizes a drag force on the wall-adhered thrombus. If catheter tube14is advanced far enough into the thrombetic deposits or lesions118, the flow may stop when self-inflating balloon42inflates thereby pushing outflow orifices44a-44ndirectly against the thrombetic deposits or lesions118. When this occurs, high velocity fluid jet streams114drive deeply into thrombetic deposits or lesions118and gradually soften and then break apart the thrombetic deposits or lesions118. Once broken, the entrained thrombus is macerated into microscopic particles and re-entrained into inflow gap40at a high rate. Some of the macerated particles re-exit from outflow orifices44a-44nalong with high velocity fluid jet streams114but are not of sufficient size to significantly block circulation. In a no-flow situation, material can then be recirculated and rediluted until all particles are removed and all that remains is saline. Cessation of fluid flow in a blood or other conduit maximizes the effect of rheolytic thrombectomy catheter10in terms of debris or tissue removal. Also, cessation of fluid flow in a blood vessel or other internal conduit maximizes the effect of the rheolytic thrombectomy catheter10when incorporated into use with a distal protection filter wire or a balloon.

FIG. 8, a first alternative embodiment, is an illustration similar toFIG. 2showing a rheolytic thrombectomy catheter10ahaving a single inflow orifice122in lieu of inflow gap40of the first embodiment, where all numerals correspond to those elements previously described or as otherwise described herein. In the alternative, more than one inflow orifice could be utilized instead of single orifice122.FIG. 9is an illustration similar toFIG. 4showing the distal end of rheolytic thrombectomy catheter10aand the arrangement of a single inflow orifice122in relation to self-inflating balloon42. In this embodiment, catheter tube14extends across the former location of inflow gap40of the first embodiment and is continuous thereacross to form tapered flexible tip38in which fluid jet emanator52is secured in the manner previously described. The mode of operation closely parallels that of the preferred embodiment ofFIG. 1, whereby inflow orifice122, instead of inflow gap40, is used to receive cross stream jets120.

FIG. 10, a second alternative embodiment, is an illustration similar toFIG. 8showing a rheolytic thrombectomy catheter10b, where all numerals correspond to those elements previously described or as otherwise described herein. An additional feature of rheolytic thrombectomy catheter10bis a fluid jet emanator52acorresponding in general design to that of fluid jet emanator52shown inFIG. 11, but including features which provide for the emanation of outwardly directed high velocity fluid radial jets124a-124ntherefrom.

FIG. 11is an illustration similar toFIG. 5showing a fluid jet emanator52a, where all numerals correspond to those elements previously described or as otherwise described herein. Additional uniformly aligned and spaced orifices126a-126n, preferably in radial and perpendicular orientation with respect to the longitudinal axis, are arranged about a peripheral circumference of fluid jet emanator52aand are in communication with an internal manifold (not shown) and with jet orifices112a-112nand provide for outwardly directed emanation of high velocity fluid radial jets124a-124ntherefrom. In the alternative, the orientation of orifices126a-126ncan be randomly angulated with respect to perpendicular orientation in order to provide high velocity fluid radial jets124a-124nat other than perpendicular emanation therefrom and directed as desired.

FIG. 12is an illustration similar toFIG. 9showing the distal end of rheolytic thrombectomy catheter10band the arrangement of an inflow orifice122and the arrangement of jet orifices126a-126nof fluid jet emanator52ain relation to self-inflating balloon42. Also shown is the plurality of holes128a-128nextending through the wall of the distal portion of catheter tube14in corresponding alignment with jet orifices126a-126n. High velocity fluid radial jets124a-124n(FIG. 11) emanate through the jet orifices126a-126nand through the plurality of holes128a-128nin order to provide treatment distal to the general flow of cross stream jets120, as shown and described inFIG. 13.

FIG. 13is an illustration similar in operation toFIG. 7showing flexible rheolytic thrombectomy catheter10bin the performance of the method and use thereof. For purposes of illustration, inflow orifice122is oriented toward the viewer. The use of radially directed high velocity fluid radial jets124a-124nfrom radial jet orifices126a-126nprovides for jet impingement of the thrombotic deposits or lesions118adjacent to the region of inflow orifice122in order to provide a substantially unrestricted path for the flow of cross stream jets120and particulate118ainto inflow orifice122for further maceration and/or carriage of fluids and particulate proximally through inflated balloon42aand catheter tube14or for recirculation. Additionally, drugs for treatment or for lysing of the thrombotic deposits or lesions118can also be delivered via radial jet orifices126a-126nin addition to outflow orifices44a-n, in order to soften the thrombotic deposits or lesions118in the region adjacent to inflow orifice122and outflow orifices44a-n, thereby benefiting and making the use of cross stream jets120more effective. The drugs are delivered through the high pressure tube50to the sites of the thrombotic deposits or lesions118.

Various modifications can be made to the devices of the present disclosure without departing from the apparent scope thereof.