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"Multi-Lumen Central Access Vena Cava Filter Apparatus and Method of Using Same" in Patent Application Approval Process

July 14, 2014



By a News Reporter-Staff News Editor at Cardiovascular Week -- A patent application by the inventors Angel, Luis F. (San Antonio, TX); STEINMETZ, Jeffrey N. (Arvada, CO), filed on December 20, 2013, was made available online on July 3, 2014, according to news reporting originating from Washington, D.C., by NewsRx correspondents (see also Biotechnology Companies).

This patent application is assigned to BiO2 Medical, Inc.

The following quote was obtained by the news editors from the background information supplied by the inventors: "The present invention pertains generally to the filed of vascular filters for capturing embolic material in the blood flow. More particularly, the present invention relates to multi-lumen central access catheter having a proximal end and a distal end thereof relative to the longitudinal axis of the catheter, a vena cava filter near the distal end of the central access catheter, at least one of a port proximal the vena cava filter or a port distal the vena cava filter and plural fluid infusion ports passing through walls of the central access catheter and positioned to deliver fluid to a space delimited by the vena cava filter. The plural fluid infusion ports are positioned in the walls of the central access catheter and have a directional flow orientation such that any or all regions of the space delimited by the vena cava filter may be exposed to fluid flow there from. The proximal and distal ports, which may be positioned entirely or partially distant from an open area bounded by the filter member, permit measuring pressure and/or flow velocity across the filter as a determinant of extent of capture of embolic material in the filter or for measuring flow rate at the position of the filter member as a positional indicator within the body. Pressure or flow sensing may be accomplished by a hydrostatic fluid column in communication with each of the proximal and distal ports and a pressure transducer operably associated with a proximal end of the central access catheter. Alternatively, pressure or flow sensors may be disposed either within the proximal and distal ports or within lumens communicating with the proximal and distal ports. Preferably, the proximal and distal ports, and lumens associated therewith, are also open to fluid flow to provide means for introducing fluids, such as an anticoagulant, thrombolytic or other bioactive agents, contrast medium, blood transfusions, intravenous fluids or other medications. Alternatively, the proximal and distal ports may be used for withdrawal or evacuation of fluids or other material through the catheter. The multiple infusion ports also provide a means for introducing a flushing medium, such as saline, under elevated pressure to produce mechanical thrombolysis or induce thrombolysis by the infusion of thrombolytic agents directly to thrombus within the filter.

"The present invention may be configured for either a femoral approach or a jugular approach to the inferior vena cava. Vena cava filters are typically deployed infrarenaly, but may also be deployed suprarenaly. It will be understood that within the inferior vena cava blood flow is superior, i.e., toward the patients head. Thus, in all embodiments, the vena cava filter will be positioned so that it opens inferiorly, i.e., away from the patient's head and toward the direction of the blood flow. It will be appreciated, therefore, that in the present invention, the vena cava filter will have a different axial orientation on the central access catheter depending upon whether the device is intended for use in a femoral approach or a jugular approach."

In addition to the background information obtained for this patent application, NewsRx journalists also obtained the inventors' summary information for this patent application: "The accepted standard of care for patients with venous thromboembolism (VTE) is anticoagulant therapy. Inferior vena cava (IVC) filters are reserved for those patients who fail anticoagulant therapy, or have a complication or contraindication to anticoagulant therapy. Until the early 1970's, the only method of IVC interruption was surgical, either by clipping, ligation or plication. The first clinical experience of an endoluminally-placed device to interrupt IVC flow was reported by Mobin-Uddin et al. in 1969. However, it was not until the introduction of a stainless steel umbrella-type filter by Greenfield et al. in 1973 that an effective method of endoluminally trapping emboli while simultaneously preserving IVC flow became possible. Indeed, for many years, the Greenfield filter set a benchmark by which newer filters were measured. Early generations of filters were inserted by surgical cut-down and venotomy.

"Eventually filters were able to be inserted percutaneously: initially through large 24 Fr sheaths, though newer generations of filters are able to be delivered through 6 Fr systems.

"Despite the safety and efficacy of modern day filters, systemic anticoagulation remains the primary treatment for VTE. Either unfractionated or low molecular weight heparin followed by three months of oral anticoagulation in patients with proximal deep venous thrombosis (DVT) is approximately 94% effective in preventing pulmonary embolism (PE) or recurrent DVT. The routine placement of IVC filters in addition to anticoagulation in patients with documented DVT was investigated by Decousus et al. in a randomized trial. Decousus H, Leizorovicz A, Parent F, et al. A clinical trial of vena caval filters in the prevention of pulmonary embolism in patients with proximal deep-vein thrombosis. N Engl J Med 1998;338:409-415. This study revealed that the use of a permanent filter in addition to heparin therapy significantly decreased the occurrence of PE within the first 12 days compared to those without a filter. However, no effect was observed on either immediate or long-term mortality, and by 2 years, the initial benefit seen in the group of patients with filters was offset by a significant increase in the rate of recurrent DVT.

"Despite the efficacy of anticoagulant therapy in the management of VTE, there are certain situations and conditions in which the benefits of anticoagulation are outweighed by the risks of instituting such a therapy. These include contraindications and complications of anticoagulant therapy. In such circumstances, there may be absolute or relative indications for filter insertion

"Currently, there are eight different types of permanent cava filters that are FDA approved. These include the Bird's Nest filter (Cook Incorporated, Bloomington, Ind.), Vena Tech LGM filter (B. Braun, Bethlehem Pa.), Vena Tech LP (B. Braun), Simon Nitinol filter (Bard, Covington, Ga.), Titanium Greenfield filter (Boston Scientific, Natick Mass.), Over-the-Wire Greenfield filter (Boston Scientific), TrapEase filter (Cordis Corp.) and the Gunther Tulip filter (Cook Inc.)

"Well-founded concerns over the long-term complications of permanent IVC filters, particularly in younger patients in need of PE prophylaxis with a temporary contraindication to anticoagulation, has led to the development of temporary and retrievable filters. Temporary filters remain attached to an accessible transcutaneous catheter or wire. These have been used primarily in Europe for PE prophylaxis during thrombolytic therapy for DVT. Currently these devices are not approved for use in the United States. Retrievable filters are very similar in appearance to permanent filters, but with modifications to the caval attachment sites and/or hooks at one end that can facilitate their removal. Retrievable filters are currently available in the United States, examples of these include the Gunther Tulip (Cook Inc.), Opt Ease (Cordis Corp.), and Recovery nitinol filters (Bard Peripheral Vascular, Tempe, Ariz.) Lin P H, et al., Vena caval filters in the treatment of acute DVT. Endovascular Today 2005; Jan:40-50. The time limit of retrievability is in part dependant on the rate of endothelialization of the device, which typically occurs within 2 weeks. However, differences in design may extend the time period in which the filter may be safely retrieved.

"Currently no consensus exists as to which patients have an indication for a retrievable filter. However, it is generally accepted that patients at high risk for pulmonary embolism or with documented PE and with a temporary contraindication to anticoagulation are candidates.

"Certain circumstances preclude the placement of a filter in the infrarenal IVC. This includes thrombus extending into the infrarenal IVC, renal vein thrombosis or pregnancy. The safety of suprarenal placement of IVC filters is well documented, with no reported instances of renal dysfunction and no differences in the rates of filter migration, recurrent PE or caval thrombosis.

"The rate of upper extremity DVT is on the rise. This is predominantly due to an increasing number of patients having short- and long-term upper extremity central venous access catheters. In one study, 88% of patients found to have an upper extremity DVT had a central venous catheter present at the site of thrombosis at the time of diagnosis or within the previous two weeks. Pulmonary embolism may complicate upper extremity DVT in 12-16% of cases. In patients who have such a complication or contraindication to anticoagulation, a filter can be safely placed immediately below the confluence of the brachiocephalic veins. However, misplacement of an SVC filter is theoretically more likely than with an IVC filter because of the relatively short target area for deployment.

"The most common imaging modality used for filter insertion is fluoroscopy, performed either in an interventional suite or an operating room. Bedside placement of filters has inherent advantages, particularly for critically ill patients in intensive care settings where transport can be avoided. Portable fluoroscopy, surface duplex ultrasound and intravascular ultrasound (IVUS) have all been used to assist with bedside filter placement.

"Vena cava filter placement frequently occurs concomitantly with central access line placement or in critically ill patients that already have a central access line in place. Heretofore, however, there have been no devices which combine the function of a central access catheter and a removable vena cava filter.

"Accordingly, it is an objective of the present invention to provide a multi-lumen catheter coupled to a vena cava filter that is useful both as a central venous access catheter for administration of intravenous fluids, bioactive agents, contrast agents, flushing agents, pressurized fluids for mechanical thrombolysis and/or withdrawal of blood samples and for capture of thrombus or emboli.

"Another aspect of the present invention is to provide a filter geometry in which the proximal portion of the filter, relative to the axis of blood flow, has larger interstitial openings to permit thrombus or embolic material to flow into the filter, while the distal portion of the filter, again relative to the axis of blood flow, has relatively smaller interstitial openings that capture the thrombus or embolic material within the filter. Another way to view this aspect is that the structure of the filter includes a greater open surface area exposed to the flow of embolic material into the filter at its proximal end, while the distal end has smaller open surface area exposed to the flow of embolic material to capture the embolic material in the distal end of the filter member. More specifically, regardless of whether the present invention is delivered by a jugular approach or a femoral approach, the filter geometry is such that the larger interstitial openings of the filter are positioned inferiorly along a longitudinal axis of the filter.

BRIEF DESCRIPTION OF THE DRAWINGS

"FIG. 1 is a perspective view of a central venous access vena cava filter catheter in accordance with a first embodiment of the present invention with the vena cava filter in an unexpanded state.

"FIG. 2 is a side elevational view of a central venous access vena cava filter catheter in accordance with the first embodiment of the present invention.

"FIG. 3. is a cross-sectional view taken along line 3-3 of FIG. 2.

"FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 2.

"FIG. 5 is a cross-sectional view taken along line 5-5 of FIG. 2.

"FIG. 6 is a perspective view of a central venous access vena cava filter catheter in accordance with a second embodiment of the present invention illustrating the vena cava filter in an unexpanded state.

"FIG. 7 is a side elevational view of a central venous access vena cava filter catheter in accordance with the second embodiment of the present invention.

"FIG. 8 is a cross-sectional view taken along line 8-8 of FIG. 7.

"FIG. 9 is a cross-sectional view taken along line 9-9 of FIG. 7.

"FIG. 10 is a cross-sectional view taken along line 10-10 of FIG. 7.

"FIG. 11 is a cross-sectional view taken along line 11-11 of FIG. 7.

"FIG. 12 is a perspective view of the central venous access vena cava filter catheter of FIG. 1 illustrating the vena cava filter in a diametrically expanded state.

"FIG. 13A is a perspective view of a vena cava filter member in accordance with a first embodiment thereof

"FIG. 13B is a first side elevational view thereof.

"FIG. 13C is an end elevational view thereof.

"FIG. 13D is a second side elevational view thereof.

"FIGS. 14A-14H are perspective views of alternative embodiments of a vena cava filter member in accordance with the present invention.

"FIG. 15A-15H are fragmentary side elevational views of the alternative embodiments of the vena cava filter member illustrated in FIGS. 14A-14H.

"FIG. 16A is a side elevational view of the vena cava central line catheter in its undeployed state.

"FIG. 16B is a side elevational view of the vena cava central line catheter in its deployed state.

"FIG. 17 is a side elevational view of an vena cava filter member in its expanded state in accordance with one embodiment of the present invention.

"FIG. 18 is a perspective view of a vena cava filter member in its expanded state in accordance with an alternative embodiment of the present invention.

"FIG. 19 is a perspective view of a vena cava filter member in its expanded state in accordance with yet another embodiment of the present invention.

"FIG. 20 is a perspective view of a vena cava filter member in its expanded state in accordance with still another embodiment of the present invention

"FIGS. 21A and 21B are perspective views of a vena cava filter member mounted at a distal end of a central line catheter having a distal balloon.

"FIGS. 22A and 22B are perspective views of an alternative embodiment of a vena cava filter member mounted at a distal end of a central line catheter having a distal balloon."

URL and more information on this patent application, see: Angel, Luis F.; STEINMETZ, Jeffrey N. Multi-Lumen Central Access Vena Cava Filter Apparatus and Method of Using Same. Filed December 20, 2013 and posted July 3, 2014. Patent URL: http://appft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&u=%2Fnetahtml%2FPTO%2Fsearch-adv.html&r=1708&p=35&f=G&l=50&d=PG01&S1=20140626.PD.&OS=PD/20140626&RS=PD/20140626

Keywords for this news article include: Therapy, Legal Issues, BiO2 Medical Inc., Pulmonary Embolism, Risk and Prevention, Deep Venous Thrombosis, Biotechnology Companies.

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Source: Cardiovascular Week


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