Surgery – Means for introducing or removing material from body for... – Treating material introduced into or removed from body...
Reexamination Certificate
2003-06-19
2004-06-01
Casler, Brian L. (Department: 3763)
Surgery
Means for introducing or removing material from body for...
Treating material introduced into or removed from body...
C604S099020, C604S167030, C604S167060, C600S585000, C600S114000, C606S192000
Reexamination Certificate
active
06743208
ABSTRACT:
FIELD OF THE INVENTION
This invention relates generally to catheters and guidewire deployment of catheter-based treatment tools. More specifically, the invention relates to an occlusion catheter with a distal valve.
BACKGROUND OF THE INVENTION
Minimally invasive intravascular procedures are revolutionizing many surgical specialties including cardiac surgery, and are becoming common in the treatment of vascular disease. Today, balloon angioplasty is commonly used to alleviate stenotic lesions in blood vessels, thereby reducing the need for heart bypass operations. Medical balloon catheters also have been proven efficacious in treating a wide variety of blood vessel disorders such as intravascular restrictions due to atherosclerosis or restenosis.
Vascular stenoses, which may be partially or totally occluded, are often characterized by having a mineral component. A variety of different protocols have been developed for treating vascular diseases with these calcified areas. The treatment methodologies generally involve mechanically removing or reducing the size of the stenosis, mechanical debridement, atherectomy, balloon angioplasty, stenting, and bypass surgery procedures.
In exemplary intravascular procedures, a balloon catheter dilates an intravascular restriction, or an atherectomy catheter removes the restriction. Unfortunately, the intravascular procedures associated with these devices may result in embolic particles being dislodged while the restriction is dilated or cut. In addition, the dislodged embolic particles may move downstream from the area of restriction and cause another embolism to form, which, in turn, could compromise the flow of blood to the surrounding tissue.
In response to this problem of dislodged particles, occlusion balloon catheters and aspiration catheters have been developed to help prevent dislodged embolic particles from entering the blood stream. The occlusion balloon catheter blocks or impedes blood flow while the aspiration catheter aspirates and removes embolic particles from the area of the stenosis.
Proposed aspiration methods that use an aspiration catheter are described in “Methods for Reducing Distal Embolization”, Imran, U.S. Patent Publication 20030055398 published Mar. 20, 2003. One method crosses the stenosis with a guidewire while aspirating blood, so that blood flows past the stenosis and emboli debris are removed, after which the primary treatment of the stenosis can begin. Another method, which treats a vessel stenosis, involves advancing a guidewire and a first catheter to a location near the stenosis, aspirating particles through the lumen of the first catheter; delivering a therapy catheter to a location near the stenosis; and performing treatment on the stenosis using the therapy catheter.
Occlusion balloon catheters are usually used in conjunction with other catheters, particularly an aspiration catheter. An occlusion catheter, which often includes an elongated shaft and a distally mounted occlusion or attenuation balloon, typically extends through a lumen of a primary dilation or atherectomy catheter. The balloon is advanced through a vessel, positioned distal to the site of the stenosis, and temporarily inflated to prevent embolic particles from flowing downstream as the occlusive restriction is being dilated or cut. After the restriction has been treated, the primary catheter can be removed from over the guidewire of the occlusion balloon catheter. An aspiration catheter can then be advanced proximal to the stenosis to reduce or eliminate the blockage by aspirating the treatment site. Once the embolic particles have been aspirated, the occlusion balloon is deflated and removed from a patient.
An exemplary occlusion catheter and associated occlusion and aspiration method uses a catheter and a guidewire having a hollow shaft and a flexible, shapeable guidewire distal tip. A deflated elastomeric occlusion balloon is located at the proximal end of the distal tip of the guidewire. The distal tip of the guidewire and the balloon crosses the lesion, an inflation device is attached to the proximal end of the catheter, and the occlusion balloon is inflated with dilute contrast agent. Following the inflation of the balloon, an angiogram using fluoroscopy may be taken to ensure complete occlusion by the balloon. The hollow guidewire can be used to infuse or deliver fluoroscopic material or therapeautic agents to the treatment site. The inflation device can be removed from the proximal end of the wire while the occlusion balloon remains inflated, and then a stent-delivery catheter maybe exchanged to provide percutaneous transluminal angioplasty. With the occlusion balloon inflated, balloon angioplasty or stenting may be performed. The embolic particles that are released during a coronary angioplasty or stenting procedure remain trapped in the artery upstream of the occlusion balloon. Following the removal of the angioplasty balloon catheter, an aspiration catheter may be introduced over the guidewire to aspirate the particles.
A specific example of an occlusion catheter is described by Rauker and others in “Occlusion Device”, U.S. Pat. No. 6,475,185 issued Nov. 5, 2002. The occlusion device includes an elongated tubular shaft having an inflatable balloon disposed near the elongate shaft distal end with a proximal seal of a sufficiently small profile to allow a second catheter to pass over the distal occlusion device while the inflatable balloon remains uninflated. One occlusion device includes an elongated fluid displacement rod within the elongated shaft of the occlusion device, providing both a fluid pressure source and a seal.
Controlling the flow and sealing the inflation fluid into the balloon of the occlusion catheter can be challenging. Sell and others have used a valve of an inner tube that is closely fit into an outer tube, as disclosed in “Low Profile Valve and Balloon Catheter”, U.S. Pat. No. 6,090,083 issued Jul. 18, 2000. The low-profile inflation valve includes a first thermoplastic tube with at least one region of decreased inner diameter, and a structure, which may be a tube, movably located inside the lumen. The region of decreased inner diameter of the first tube forms a seal with a portion of the structure.
Many medical procedures require that more than one catheter be advanced in and out of a body vessel. Various solutions have been suggested to allow a more rapid, safe, and unobstructed exchange of catheters. Improvements to catheter designs, fittings, valves, other parts of catheters, guidewires, and balloons have been suggested. One proposed improvement in the exchanging of catheters is to have a removable inflation fitting on the inflation tube that supplies fluid to a catheter balloon, as described in “Low Profile Angioplasty Catheter and/or Guide Wire and Method”, Imran et al., U.S. Pat. No. 5,520,645 issued May 28, 1996. The inflation fitting is removable so that the proximal extremity of the catheter is free of obstruction and another balloon catheter can be advanced over the proximal extremity.
Improvements to a balloon occlusion catheter and an associated method are proposed in “Low Profile Catheter Valve and Inflation Adaptor”, Zadno-Azizi et al., U.S. Patent Application 20020133117 published Sep. 19, 2002; “Exchange Method for Emboli Containment”, Zadno-Azizi et al., U.S. Pat. No. 6,544,276 issued Apr. 8, 2003; “Method of Emboli Protection using a Low Profile Catheter”, Zadno-Azizi et al., U.S. Pat. No. 6,500,166 granted Dec. 31, 2002; and “Low Profile Catheter Valve”, U.S. Pat. No. 6,355,014, Zadno-Azizi et al., granted Mar. 12, 2002. The catheter includes a low-profile catheter valve with a movable sealer portion positioned within the inflation lumen of a catheter. The sealer portion forms a fluid tight seal with the inflation lumen by firmly contacting the entire circumference of a section of the inflation lumen. The sealer portion is positioned proximate to a side-access inflation port on the catheter, establishing an unrestricted fluid pathway between the inflation port and an inflatable balloon
Cardinal Law Group
Casler Brian L.
Medtronic Vascular, INC
Thissell Jeremy
LandOfFree
Occlusion balloon catheter with distal valve does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Occlusion balloon catheter with distal valve, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Occlusion balloon catheter with distal valve will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3329097