US20050171446A1 - Method and apparatus for determining a blood flow during a vascular access dysfunction corrective procedure - Google Patents
Method and apparatus for determining a blood flow during a vascular access dysfunction corrective procedure Download PDFInfo
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- US20050171446A1 US20050171446A1 US11/089,797 US8979705A US2005171446A1 US 20050171446 A1 US20050171446 A1 US 20050171446A1 US 8979705 A US8979705 A US 8979705A US 2005171446 A1 US2005171446 A1 US 2005171446A1
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B17/00—Surgical instruments, devices or methods, e.g. tourniquets
- A61B17/22—Implements for squeezing-off ulcers or the like on the inside of inner organs of the body; Implements for scraping-out cavities of body organs, e.g. bones; Calculus removers; Calculus smashing apparatus; Apparatus for removing obstructions in blood vessels, not otherwise provided for
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/02—Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
- A61B5/026—Measuring blood flow
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/02—Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
- A61B5/026—Measuring blood flow
- A61B5/0261—Measuring blood flow using optical means, e.g. infrared light
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/02—Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
- A61B5/026—Measuring blood flow
- A61B5/0275—Measuring blood flow using tracers, e.g. dye dilution
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/02—Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
- A61B5/026—Measuring blood flow
- A61B5/0275—Measuring blood flow using tracers, e.g. dye dilution
- A61B5/028—Measuring blood flow using tracers, e.g. dye dilution by thermo-dilution
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M25/00—Catheters; Hollow probes
- A61M25/10—Balloon catheters
- A61M25/104—Balloon catheters used for angioplasty
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Abstract
A method and apparatus for determining an angioplasty induced blood flow changes, wherein the apparatus includes the catheter having a port for introducing a blood property change in a downstream sensor. The downstream sensor and the catheter are configured to space the sensor from an adjacent vessel wall so as to minimize effects of the vessel wall during sensing of the blood property change.
Description
- The present application is a continuation of U.S. application Ser. No. 09/241,455 filed Feb. 2, 1999, herein incorporated by reference.
- Not Applicable.
- Not applicable.
- The use of intravascular catheters for treatment of the body is well known in the field of medicine. The use of dilation or balloon catheters has become widespread in the treatment, for example, of restrictions within the coronary blood vessels, such as stenotic lesions. In balloon angioplasty, a catheter carrying a balloon at its distal end is guided through the blood vessel to a point adjacent the lesion. The placement of the balloon is aided by use of a fluoroscope and radiopaque elements. The size and type of the balloon is generally selected by the physician based on his knowledge of the size and type of lesion. The balloon is then expanded by providing an expansion fluid from the proximal end of the catheter through a fluid lumen within the catheter to the balloon. The expanded balloon acts on the lesion in a manner to reopen at least a portion of the restricted vessel. The balloon is then deflated for removal from the body, though sometimes repeated reinflation may be deemed necessary by the physician prior to removal.
- Though balloon angioplasty is well known as a safe and effective method for treatment of the vascular disease described above, there are still problems that arise during the procedure. For example, stenotic lesions often have a highly irregular cross-sectional configuration, and may vary greatly in their hardness, both of which make for difficulty in determining what size and composition of balloon to use, and how often to inflate it. These complications further compound the problem of determining the efficacy of the procedure.
- Traditionally, the angioplasty procedure is performed, the catheter is removed and the procedure is terminated. At a later time, days weeks or months, a measurement is taken of blood flow through the previously treated vessel. Depending upon the resulting blood flow, the patient may be again admitted to the facility and another complete angioplasty procedure performed.
- Prior methods for determining blood flow through such a reconstructed vessel include injecting a radioactive isotope and monitoring through external equipment passage of the isotope to determine blood flow.
- Alternatively, ultrasonic devices have been used to image the vessel prior to reconstruction and re-image the vessel subsequent to reconstruction to obtain two-dimensional images of the vessel. These two-dimensional images are then used as basis for calculating the blood flow through the reconstructed area.
- However, each of these procedures is relatively complex in that it involves significant external equipment. In addition, these measurements are taken before and after the entire angioplasty procedure. Thus, if sufficient flow is not restored, the entire angioplasty procedure including reinsertion must be repeated. Thus, the patient is exposed to all the complications of the procedure as well as increased hospital time.
- Therefore, need exists for a method and apparatus for determining blood flow during angioplasty procedures such that the efficacy of the procedure and reconstruction of the relevant vessel may be determined in real time. The need continues such that intra-procedural evaluation improvements in access flow may be identified. The need also exists for a relatively simple and inexpensive method and apparatus for determining the intra-procedural blood flow.
- The present invention relates to blood flow measurements and more particularly, to the real time determination of blood flow during vascular access dysfunction corrective procedures whereby the efficacy of the procedures can be determined prior to termination of the session.
- The present invention provides a method and apparatus for the real time determination of access flow during procedures to correct vascular access dysfunction. In particular, the invention provides for the determination of flow by dilution measurement. By determining intra-procedural access flow, the effectiveness of the surgical revision can be promptly assessed and appropriate remedial action promptly taken. As a physician can immediately and accurately determine intervention effectiveness, the procedure may be “tuned” to provide optimal access flow.
- The surgical revision may include angioplasty, angioplasty of the arteries and angioplasty of the veins as well as hemodialysis grafts. The access flow may be measured in vascular grafts, arteriovenous shunts, arteriovenous grafts, transcutaneous shunts or fistulas, as well as arteries, veins, vascular ducts and channels, collectively referred to as “vessels”.
- The present apparatus includes an elongate catheter having an indicator introduction port and a blood property sensor spaced downstream from the port. In addition, it is contemplated the catheter may include a selectively expanding member such as an angioplasty balloon. Thus, the present invention provides an angioplasty catheter with a blood property sensor, wherein the any resulting change in flow rate is determined prior to removal of the catheter.
- The present method provides for inserting the angioplasty catheter into a relevant vessel to locate the indicator introduction port upstream of a blood property sensor; locating the sensor to minimize wall effects; forming a first indicator bolus in the bloodstream upstream of the sensor; measuring passage of the first bolus past the sensor; calculating the blood flow in response to the passage of the first indicator bolus, performing the angioplasty procedure; introducing a second indicator bolus through the indicator introduction port; measuring passage of the second indicator bolus past the downstream sensor; and calculating the resulting change in flow. It is understood the vessel may include any vascular passage through which it is desired to measure flow.
- As the measurements and calculations are done in real time, an operator is immediately provided an intra-procedural quantitative measurement of flow through the respective vessel in response to the surgical procedure.
- In addition, the blood property sensor may be configured to minimize wall effects on the signal from the sensor. That is, the sensor and catheter are configured to maximize sensitivity to the relevant blood property and minimize effects from the local region of the vascular wall. Further, the system is configured to balance the need for a sufficient indicator volume to produce a high quality dilution curve having an acceptable signal-to-noise ratio against an overwhelming of the initial access flow by the introduced indicator. The present system also allows for minimizing the effect indicator introduction on the measured blood volume.
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FIG. 1 is a side elevational view of a catheter and an angioplasty expander member. -
FIG. 2 is a schematic view of a catheter end and angioplasty expander member. -
FIG. 3 is an enlarged cross sectional view of the angioplasty expander member in an expanded configuration. -
FIG. 4 is a schematic view of a first configuration of the invention in an operative environment. -
FIG. 5 is a schematic view of a second configuration of the invention in an operative environment. -
FIG. 6 is a schematic view of an alternative application of the second configuration in an operative environment. -
FIG. 7 is a graph representing passage of the indicator bolus past the sensor. -
FIG. 8 is a side elevational view of a portion of a catheter showing a blood property sensor. -
FIG. 9 is a side elevation view taken along line 9-9 ofFIG. 8 . -
FIG. 10 is a graph representing measured electrical impedance in relation to rotation of the sensor ofFIGS. 8 and 9 adjacent a vascular wall. -
FIG. 11 is a side elevational view of an alternative sensor configuration. -
FIG. 12 is a cross sectional view taken along line 12-12 ofFIG. 11 . -
FIG. 13 is a side elevation view of an alternative introduction port configuration. -
FIG. 14 is a further alternative construction of an indicator introduction port. -
FIG. 15 is a graph representing passage of an electrical impedance indicator bolus. -
FIG. 16 is a graph representing a constant infusion of an electrical impedance indicator. - Referring to
FIGS. 1-3 , the present invention includes anelongate catheter 10 having anindicator introduction port 30 and a spaced apartblood property sensor 40. Acontroller 60 and adilution indicator source 80 are selectively connected to thecatheter 10. - The present invention provides for intra-procedural measurement of flow through the vascular section in which the catheter is located. Generally, the catheter provides for measurements relating to an inducted change in a blood property. In a preferred configuration, the change in blood property inducted by the introduction of an indicator.
- It is understood the indicator is any substance that alters a measurable blood property. The indicator may alter any measurable parameter of the blood. For example, the indicator may be chemical, optical, electrical, thermal or any combination thereof. The particular indicator is at least partly dictated by the anticipated operating environment. Available indicators include saline solutions, increased or decreased temperature as well as dyes and various isotopes. The use of temperature differentials may be accomplished by locally creating a heat source or a heat sink in the surrounding flow. The creation of a local temperature gradient offers the benefit of being able to employ a dilution indicator without introducing any additional volume into the blood flow. That is, a temperature differential may be created without an accompanying introduction of a volume of indicator. Alternatively, a volume of heated or cooled blood may be introduced at the
indicator introduction port 30 as the indicator. - Further, the present invention is applicable in a variety of flows including vascular grafts, arteriovenous (AV) shunts, fistula, arterial vessels, venous vessels, arteriovenous grafts, transcutaneous shunts in procedures including hemodialysis and angioplasty.
- The present invention may be employed as a dilution catheter and used in conjunction with an angioplasty catheter. Alternatively, the
dilution catheter 10 may by incorporated into an angioplasty catheter. As the angioplasty catheter incorporating theindicator introduction port 30 and the spaced apartblood property sensor 40 encompasses the invention, the description will be set forth in terms of the angioplasty catheter. - The present invention is operable in a number of fluid regimes, for purposes of clarity and consistency, the present invention is set forth in a blood flow environment. The term “upstream” of a given position refers to a direction against the flow of blood and the term “downstream” of a given position is the direction the blood flows away from the given position.
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FIG. 1 shows theangioplasty catheter 10, thecontroller 60 and thedilution indicator source 80. Theangioplasty catheter 10 has aproximal end 12 and adistal end 14, the distal end ending at aterminus 15. Theangioplasty catheter 10 is connected at itsproximal end 12 to a manifold 16 and includes anangioplasty expander member 20 at or adjacent thedistal end 14. Although theangioplasty expanding member 20 is shown as a balloon, it is understood that any of a variety of devices may be used to reduce a stenosis of a vessel. For example, rotating elements have been employed as well as relatively high pressure fluid streams or sprays, appropriate chemicals, recirculating and non recirculating devices. The present invention may be employed with any of these stenosis reducing devices or techniques, as well as those discussed subsequently in relation to thrombosis. - The
angioplasty expander member 20 is selectively expandable to occupy a first contracted cross sectional area and a larger second expanded cross sectional area. Theangioplasty expander member 20 may be any of a variety of configurations, and is referred to as a balloon. In contrast to an inflatable member for merely retaining a catheter at a location within a vessel, the present angioplasty expander member is constructed to withstand significantly higher pressures. For example, the present angioplasty balloon can withstand pressures from 5 psi up to 20 psi. - It is understood that locating balloons are used with catheters. These locating balloons are fundamentally different than angioplasty balloons. The locating balloon is an elastic member. Locating balloons are generally spherical and are capable of withstanding just sufficient pressure to partially inflate in the blood flow. Inflation pressures are relatively low, on the order of one psi. The elastic construction of the locating balloon is such that the balloon may be subject to increased inflation pressure and increased diameter up to failure. The geometry of the locating balloon is selected to allow the balloon (and accompanying catheter) to be carried along a vessel by the blood flow. That is, the geometry of the locating balloon sufficiently increases the hydrodynamic resistance to blood flow to translate the balloon and catheter along the vessel.
- In contrast, an angioplasty balloon is a generally elongate inelastic inflatable member capable of relatively high pressures. The angioplasty balloon is only expandable to a predetermined size or cross sectional area. Compared to the locating balloon, angioplasty balloons may require inflation pressures greater than 2 psi and as high as 20 psi or greater. The elongate structure of the angioplasty balloon provides for relatively complete contact along the narrowing of the vessel. That is, the spherical locating balloon presents only a point or ring of contact with the surrounding vessel. The angioplasty balloon contacts a length of the vessel to provide relatively constant pressure along the length of contact. In addition, a slight inflation of the locating balloon is used to increase a resistance to blood flow which in turn causes translation of the balloon along the vessel, thereby allowing the locating balloon to the disposed along a vessel. In contrast, a slight inflation of the angioplasty balloon permits flow around and along the balloon and does not create sufficient resistance to flow to induce translation of the balloon (and catheter) along the vessel. Use of a locating balloon to perform angioplasty would allow an elastic balloon to be inflated within the vessel such inflation of an elastic member could rupture the vessel. Alternatively, the elastic member of the locating balloon may not have sufficient strength to displace the vessel wall and perform the angioplasty.
- The manifold 16 includes
inlet ports inlet port 19 may be employed to introduce an inflation fluid through the inlet port to selectively expand theballoon 20. - Referring to
FIGS. 2 and 3 ,inlet port 17 is an indicator inlet for introducing the indicator to the catheter. Theangioplasty catheter 10 includes anindicator lumen 22 extending from theindicator inlet 17 in the manifold 16 to theindicator introduction port 30. Preferably, theindicator lumen 22 is located in the interior of theangioplasty catheter 10 and is selectively connected to theindicator source 80. Theinlet port 21 is connected to a corresponding lumen for providing communication to theblood property sensor 40. Theblood property sensor 40 is operably connected to thecontroller 60. - The
indicator source 80 may be any of a variety of configurations, but is preferably a metered dispenser of the indicator, wherein the volume of indicator and rate of indicator introduction is precisely controlled and measured. - It is also contemplated the
indicator introduction port 30 may be a local heater or cooler for selectively heating or cooling a blood flow past the indicator introduction port. In this construction, theindicator source 80 is the energy for heating or cooling the flow in the region of theindicator introduction port 30. Referring toFIG. 14 , theindicator introduction port 30 may include a heating or cooling element for creating a local temperature gradient in the passing flow. That is, theindicator introduction port 30 encompasses a local heat sink or heat source for creating temperature gradient in the surrounding flow. Thus, a dilution indicator is created without introducing an accompanying volume increase in the flow to be measured. As shown inFIG. 13 , theindicator introduction port 30 may include a plurality of radial or axial spaced orifices through which the indicator is introduced into the flow. The particular location and configuration of the orifices are selected to assist in obtaining mixing of the introduced indicator and the blood flow. - Referring to
FIG. 3 , an over-the-wireballoon angioplasty catheter 10, wherein theangioplasty balloon 20 is shown as sealed to an outer surface of the catheter. It will be recognized that the constructions of the angioplasty balloon as shown inFIG. 3 is merely representative of these elements of the various forms of balloon angioplasty catheters, and that this representative form of drawing has been selected for purposes of clarity in describing the present invention. - As shown in
FIGS. 3-6 , theblood property sensor 40 is located downstream of theindicator introduction port 30. Thus, depending upon the particular application, theindicator introduction port 30 may be intermediate thedistal end 14 of theangioplasty catheter 10 and thesensor 40, or the sensor may be intermediate the distal end of the angioplasty catheter and the indicator introduction port. - Referring to
FIGS. 4-6 , the blood flow in the vascular passage is identified as Qb, and the arterial side is identified as A and the venous side identified as V. - The
sensor 40 is sufficiently spaced from theindicator introduction port 30 to substantially ensure a complete mixing of the introduced indicator with the flow. For artificial grafts, it has been found that a distance greater than approximately 5-6 cm between theindicator introduction port 30 and thedownstream sensor 40 is sufficient to ensure mixing. It is understood that local conditions at the point of indicator introduction will effect required distance between theindicator introduction port 30 and thesensor 40. Local conditions include flow rate, turbulence, introduction rate and port configuration. Therefore, the actual distance between theblood property sensor 40 and theindicator introduction port 30 may be determined by number of parameters and the disclosed value may not apply. - The
blood property sensor 40 is selected to identify a change in a parameter of the blood. That is, a variation in a blood property is detected by thesensor 40. Theparticular sensor 40 is at least partially determined by the indicator used. As previously stated, the indicators may be any of a variety of indicator such as, but not limited to impedance, optical, thermal, electrical, density and ultrasound velocity. Thus, depending on the particular indicator, thesensor 40 is accordingly configured. Theblood property sensor 40 may be an electrical impedance sensor, an optical sensor, a thermal sensor, sound sensor or even a chemical sensor. - The
blood property sensor 40 and theangioplasty catheter 10 are constructed to provide for location of the sensor with respect to the vessel wall so as to minimize wall effects. This is particularly important for electrical impedance sensors. That is, if an electrical impedance sensor is located adjacent to the vessel wall, the impedance measured by the electrical sensor drastically increases thereby jeopardizing an accurate measurement of resistance of the blood flow. - The electrical impedance sensor records a change in the electrical impedance of the blood induced by the introduced indicator. However, it has been found that a narrow vascular passage that locates an electrical sensor adjacent the wall can render improper readings. Specifically, impedance drastically increases upon locating the sensor in contact with the vascular wall. Thus, a configuration of the present invention includes a
sensor 40 constructed to maximize sensitivity to blood electrical impedance and minimize sensitivity to the vessel wall. - In one configuration as shown in
FIGS. 8 and 9 , theelectrical impedance sensor 40 includes a pair of spaced apartconductive rings 42 on thecatheter 10. Eachring 42 includes a non conducting portion or break 44. Thenon conducting portion 44 may alternatively be formed by disposing an insulating layer on a portion of thering 42. The insulating layer may be a biologically appropriate paint. Thenon conducting portion 44 is used in locating the catheter with respect to the vascular wall. Thesensor 40 is constructed so that the electrical field will preferentially propagate in the blood. Therings 42 are sufficiently close to each other so that the electrical field is confined to a relatively small volume between the rings. - In an alternative configuration to minimize wall effects, a plurality of spaced sensor may be located about a circumference of the
catheter 10. In this configuration, the conductive portion of the ring is again designated as 42 and the non conductive portion is set forth as 44. In this construction, each conductive area is operably connected to thecontroller 60. - Preferably, the conductive rings 42 are formed of stainless steel. The distance between the
conductive rings 42 is selected (1) to be sufficiently small to concentrate the electrical filed between the electrodes to minimize the influence of the vascular wall, and (2) large enough to eliminate the negative electrode effects (i.e. polarization) of highly concentrated electrical fields in a bipolar system. - Thus, the electrical impedance sensors may be located to occupy only a specific portion of the angioplasty catheter periphery. Preferably, the electrical sensors are longitudinally spaced (separated) and occupy a common longitudinal section of the periphery.
- More generally, it is understood that controlled catheter rotation may be employed to determine the best position of the sensor with respect to the vessel wall as well as the screening of signals from multiple sensors to identify the most appropriately located sensors. In addition, the sensors may be any of a variety of blood property sensors including optical, thermal and any other chemical or physical property.
- Alternatively, the
angioplasty catheter 10, or a local section of the catheter may be formed of a sufficiently rigid material so that a slight bend or curvature may be formed and retained in a length of the catheter to form a concave section. Thesensor 40 is then located within the concave section and is shielded by the concavity so as to be displaced from the adjacent vessel wall. - More generally, an outer wall of the
angioplasty catheter 10 may include a recess sized to receive thesensor 40. Upon locating thesensor 40 within the recess wall effects may be substantially precluded. - The
controller 60 is operably connected to thesensor 40 and theindicator source 80. Thecontroller 60 includes a processor for performing the calculations necessary to provide the flow rate. - The
controller 60 may be configured to provide the necessary electrical signal to the electrical impedance sensor. An anticipated frequency will be approximately 100 kHz. - For example, in measuring hemodialysis vascular access flow, the
controller 60 measures the access flow by monitoring the passage of completely mixed indicator in the blood. Referring toFIG. 7 , the concentration curve resulting from the introduction and mixing of the indicator is recorded by the sensor. Access flow, AF, is then calculated according to:
where V is the volume of indicator introduced, ∫C(t)dt is the area under the dilution curve that is equal to the average concentration of the indicator in the flow for the duration of the curve multiplied by the duration of the duration of the curve. - To provide accuracy of the measurement, as shown in
FIGS. 4-6 , the indicator should by completely mixed with the flow and effects resulting from the proximity of the vascular wall and the sensor should be minimized. - For the electrical impedance dilution sensor, the access flow, AF, can be calculated according to:
where Zb is the electrical impedance of the blood and Zi is the electrical impedance of the indicator (in ohms); and ΔZb(t) is the change in electrical impedance from a baseline at time t due to the injection of the indicator. - More specifically, the access flow for a bolus injection, as shown in
FIG. 11 , may be calculated from:
where V is the volume of the saline bolus [ml], Zb is the blood electrical impedance measured in ohms, ZS is the saline electrical impedance measured in ohms, S % is the concentration of saline, ΔZb(t)is the change in the electrical impedance from a baseline at time t due to injection of the indicator in ohms, ∫ΔZb(t)S %dt is the area under the blood electrical impedance dilution curve [ohm x min.]. - Similarly, the access flow for a constant infusion, as shown in
FIG. 12 , may be determined from:
where QS % is the infusion speed of the saline [ml/min], Zb is the blood electrical impedance measured in ohms, ZS is the saline electrical impedance measured in ohms, S % is the concentration of saline, and ΔZb(t)S % the blood electrical impedance baseline shift corresponding to the saline infusion. - The
controller 60 may be further configured to determine an effective cross sectional area of the vascular access. Effective cross sectional area directly effects the hydrodynamic resistance of the vascular access and may be useful as an additional independent criteria of vascular access condition. - As the
controller 60 is connected to or receives the time, t, of indicator injection by theindicator source 80 and the sensor provides a signal corresponding to passage of the indicator, the transit time of the indicator between theindicator introduction port 30 and thesensor 40 is provided to the controller. Thecontroller 60 multiplies the transit time by the calculated access flow to determine the volume between theindicator injection port 30 and thesensor 40. That is, the flow rate equals the cross sectional area multiplied by the flow velocity. Thus, the effective cross sectional area S may be calculated from:
where MTT is the mean transit time of the indicator passing the distance L from theindicator injection port 30 to thesensor 40.
Operation - In operation, the
angioplasty catheter 10 may be employed in either of two configurations, (i) where thedistal end 14 of the angioplasty catheter is the upstream portion of the angioplasty catheter as shown inFIG. 4 , or (ii) where the distal portion of the angioplasty catheter is the downstream end, as shown inFIG. 5 . In either configuration, theangioplasty catheter 10 is inserted into the vessel to locate theindicator introduction port 30 upstream of thesensor 40. - An indicator is introduced through the
indicator introduction port 30 from theindicator source 80. It is understood that if a thermal indicator were employed, the localized heating or cooling of the blood flow would not result in any introduction of indicator, but would be an indicator formation. The indicator is thus formed or introduced upstream of thesensor 40. - As at least partially determined by the environment, the
sensor 40 is located a sufficient distance downstream of theindicator introduction port 30 to ensure mixing of the indicator with the blood flow. - The
sensor 40 is located to minimize the wall effects. As shown inFIG. 10 by rotating the catheter, therings 42 are moved relative to the adjacent vascular wall. By rotating thesensor 40 to locate the orientation of minimal impedance, as shown between the lines on the graph, the sensor is located to measure the electrical impedance from the blood flow, rather than the adjacent wall. Thus, thecatheter 10 is rotated to locate thesensor 40 so that the impedance is minimal. - If the configuration of the electrical sensor having a plurality of circumferentially spaced conductive areas is employed, the resulting impedance measurement is monitored for each area and those areas having adverse wall effects are not employed by the
controller 60, while those areas having a minimized wall effect are relied upon by thecontroller 60. - Alternatively, the
controller 60 will simultaneously employ the signals of all sensors using an algorithm to optimize the results with best elimination of wall effects. Alternatively, the plurality of sensors may be read by the controller in a sequential manner and the appropriate sensor(s) employed. - The blood flow causes the indicator bolus to pass the
downstream sensor 40. Passage of the bolus is measured by thesensor 40. The blood flow may then be calculated by thecontroller 60. - The angioplasty procedure is then performed. That is, the angioplasty balloon is inflated and the vessel is locally expanded. It is understood the procedure may be any of the previously recited operations.
- A subsequent blood flow measurement is then taken again by introducing a second indicator bolus (or forming a second indicator bolus) upstream of the
sensor 40, and measuring passage of the bolus past the sensor and calculating the flow rate. - The operator may thus readily identify any increase in blood flow through the vessel and repeat the procedure as necessary.
- It is understood that some procedures, such as vascular access in hemodialysis, there may be sufficient vessel volume to accommodate two catheters. In such situations it is anticipated an angioplasty catheter and a separate dilution sensor catheter may be employed. That is, the
expander balloon 20 is located on a separate catheter from thesensor 40. In this operating configuration, the present system again allows for intra-procedural measurement of the flow by employing the dilution techniques set forth herein, for flow measurement before, during and after the angioplasty procedure. - It is also considered that the present invention may be employed subsequent to an angioplasty procedure. That is, in using either the combined angioplasty-sensor catheter or separate angioplasty catheter and sensor catheter, the angioplasty procedure may be performed and then the blow flow determined. Although no prior measurement is made with device, an after angioplasty measurement can be made. The after angioplasty measurement may be compared to a base line value, if desired.
- It is understood, the present invention is applicable to corrective procedures for thombosed or malfunctioning vascular access as well as occluded or partially occluded vessels, including but not limited to, stenosed ducts, channels, canals, tubes, vessels or the like. The term stenosis is taken to encompass all these terms as well as any narrowing or reduction of a passage through which flow is to be restored. The use of the present invention in connection with the procedure provides the real time evaluation of the procedure.
- The corrective procedures include, but are not limited to, the removal of a thrombus, angioplasty, atherectomy or dislodgment of a thrombus. The removal of a thrombus may be accomplished in a variety of ways including (i) pharmacomechanical thrombolysis using urokimas; (ii) pulse-spray thrombolysis using herparinized saline; (iii) balloon thrombectomy techniques; and (iv) mechanical thrombectomy devices, including recirculation type devices and non-recirculation type devices.
- In addition, the flow calculation may be performed prior to the corrective procedure, after the corrective procedure or before and after the corrective procedure, to provide intra-procedural flow measurements.
- Thus, the present invention provides intra-operative evaluation of access flow during surgical procedure to allow more rapid restoration of a more functional graft, extend access life and reduce the incidence and expense of full access revision surgery. The immediate feedback of access flow, including arterial and venous flow, in response to the angioplasty permits the operator to maximize the effect of the procedure as well as reduce the need for repeating the procedure.
- While the invention has been described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation of material to the teachings of the invention without departing from the scope of the invention. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope and spirit of the appended claims. CLAIM OR claims
Claims (2)
1. An apparatus for determining a blood flow in a vessel, comprising:
(a) an elongate catheter having an angioplasty balloon, a blood property change port and a downstream sensor spaced from the port for producing a signal corresponding to a blood property.
2. A method of monitoring blood flow during angioplasty, comprising:
(a) inserting an angioplasty catheter into a vessel;
(b) expanding the angioplasty catheter;
(c) introducing a first blood property change;
(d) detecting passage of the first blood property change past a downstream sensor on the catheter; and
(e) calculating the blood flow in response to the change in blood property and passage of the blood property past the downstream sensor.
Priority Applications (1)
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US11/089,797 US20050171446A1 (en) | 1999-02-02 | 2005-03-25 | Method and apparatus for determining a blood flow during a vascular access dysfunction corrective procedure |
Applications Claiming Priority (2)
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US09/241,455 US6986744B1 (en) | 1999-02-02 | 1999-02-02 | Method and apparatus for determining blood flow during a vascular corrective procedure |
US11/089,797 US20050171446A1 (en) | 1999-02-02 | 2005-03-25 | Method and apparatus for determining a blood flow during a vascular access dysfunction corrective procedure |
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US09/241,455 Continuation US6986744B1 (en) | 1999-02-02 | 1999-02-02 | Method and apparatus for determining blood flow during a vascular corrective procedure |
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US20050171446A1 true US20050171446A1 (en) | 2005-08-04 |
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US09/241,455 Expired - Lifetime US6986744B1 (en) | 1999-02-02 | 1999-02-02 | Method and apparatus for determining blood flow during a vascular corrective procedure |
US11/089,797 Abandoned US20050171446A1 (en) | 1999-02-02 | 2005-03-25 | Method and apparatus for determining a blood flow during a vascular access dysfunction corrective procedure |
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Publication number | Priority date | Publication date | Assignee | Title |
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US8784336B2 (en) | 2005-08-24 | 2014-07-22 | C. R. Bard, Inc. | Stylet apparatuses and methods of manufacture |
US8968204B2 (en) * | 2006-06-12 | 2015-03-03 | Transonic Systems, Inc. | System and method of perivascular pressure and flow measurement |
US8388546B2 (en) | 2006-10-23 | 2013-03-05 | Bard Access Systems, Inc. | Method of locating the tip of a central venous catheter |
US7794407B2 (en) | 2006-10-23 | 2010-09-14 | Bard Access Systems, Inc. | Method of locating the tip of a central venous catheter |
WO2009061769A1 (en) * | 2007-11-06 | 2009-05-14 | Alfred E. Mann Institute For Biomedical Engineering At The University Of Southern Califorina | Measurement of hematocrit and cardiac output from optical transmission and reflection changes |
US9649048B2 (en) | 2007-11-26 | 2017-05-16 | C. R. Bard, Inc. | Systems and methods for breaching a sterile field for intravascular placement of a catheter |
US10524691B2 (en) | 2007-11-26 | 2020-01-07 | C. R. Bard, Inc. | Needle assembly including an aligned magnetic element |
US10449330B2 (en) | 2007-11-26 | 2019-10-22 | C. R. Bard, Inc. | Magnetic element-equipped needle assemblies |
US9636031B2 (en) | 2007-11-26 | 2017-05-02 | C.R. Bard, Inc. | Stylets for use with apparatus for intravascular placement of a catheter |
US10751509B2 (en) | 2007-11-26 | 2020-08-25 | C. R. Bard, Inc. | Iconic representations for guidance of an indwelling medical device |
US8781555B2 (en) | 2007-11-26 | 2014-07-15 | C. R. Bard, Inc. | System for placement of a catheter including a signal-generating stylet |
ES2651898T3 (en) | 2007-11-26 | 2018-01-30 | C.R. Bard Inc. | Integrated system for intravascular catheter placement |
US8849382B2 (en) | 2007-11-26 | 2014-09-30 | C. R. Bard, Inc. | Apparatus and display methods relating to intravascular placement of a catheter |
US9521961B2 (en) | 2007-11-26 | 2016-12-20 | C. R. Bard, Inc. | Systems and methods for guiding a medical instrument |
ES2525525T3 (en) | 2008-08-22 | 2014-12-26 | C.R. Bard, Inc. | Catheter assembly that includes ECG and magnetic sensor assemblies |
US8437833B2 (en) | 2008-10-07 | 2013-05-07 | Bard Access Systems, Inc. | Percutaneous magnetic gastrostomy |
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US9445734B2 (en) | 2009-06-12 | 2016-09-20 | Bard Access Systems, Inc. | Devices and methods for endovascular electrography |
US9532724B2 (en) | 2009-06-12 | 2017-01-03 | Bard Access Systems, Inc. | Apparatus and method for catheter navigation using endovascular energy mapping |
CN102821679B (en) | 2010-02-02 | 2016-04-27 | C·R·巴德股份有限公司 | For the apparatus and method that catheter navigation and end are located |
US8706209B2 (en) | 2010-02-05 | 2014-04-22 | 3Dt Holdings, Llc | Devices, systems, and methods for measuring parallel tissue conductance, luminal cross-sectional areas, fluid velocity, and/or determining plaque vulnerability using temperature |
ES2778041T3 (en) | 2010-05-28 | 2020-08-07 | Bard Inc C R | Apparatus for use with needle insertion guidance system |
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WO2012024577A2 (en) | 2010-08-20 | 2012-02-23 | C.R. Bard, Inc. | Reconfirmation of ecg-assisted catheter tip placement |
US8801693B2 (en) | 2010-10-29 | 2014-08-12 | C. R. Bard, Inc. | Bioimpedance-assisted placement of a medical device |
US20140081154A1 (en) * | 2011-05-17 | 2014-03-20 | Landy Toth | Devices, systems, and methods for assessing implants, organs, transplants, tissues, synthetic constructs, vascular grafts, and the like |
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US11373780B2 (en) | 2011-10-06 | 2022-06-28 | 3Dt Holdings, Llc | Methods to generate elongated wires having a metallic substrate thereon and devices comprising the same |
US9734938B2 (en) | 2011-10-06 | 2017-08-15 | 3Dt Holdings, Llc | Devices and systems for obtaining conductance data and methods of manufacturing and using the same |
WO2013055896A1 (en) * | 2011-10-14 | 2013-04-18 | Acist Medical Systems, Inc. | Device and methods for measuring and treating an anatomical structure |
US9066672B2 (en) | 2011-10-27 | 2015-06-30 | 3Dt Holdings, Llc | Single injection methods for obtaining conductance measurements within luminal organs using impedance devices |
US11759268B2 (en) | 2012-04-05 | 2023-09-19 | C. R. Bard, Inc. | Apparatus and methods relating to intravascular positioning of distal end of catheter |
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US9549679B2 (en) | 2012-05-14 | 2017-01-24 | Acist Medical Systems, Inc. | Multiple transducer delivery device and method |
US10674966B2 (en) | 2012-12-11 | 2020-06-09 | Covidien Lp | Systems for diagnosing and/or treating medical conditions |
US9675257B2 (en) | 2013-03-15 | 2017-06-13 | 3Dt Holdings, Llc | Impedance devices and methods to use the same to obtain luminal organ measurements |
CN105979868B (en) | 2014-02-06 | 2020-03-10 | C·R·巴德股份有限公司 | Systems and methods for guidance and placement of intravascular devices |
US10285749B2 (en) | 2014-12-05 | 2019-05-14 | Medtronic Cryocath Lp | Determination of pulmonary vein and other vascular occlusion using temperature profile following cold saline injection |
US9956025B2 (en) * | 2014-12-05 | 2018-05-01 | Medtronic Cryocath Lp | Contrast agent to assess quality of occlusion through impedance measurement |
US10973584B2 (en) | 2015-01-19 | 2021-04-13 | Bard Access Systems, Inc. | Device and method for vascular access |
US10349890B2 (en) | 2015-06-26 | 2019-07-16 | C. R. Bard, Inc. | Connector interface for ECG-based catheter positioning system |
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WO2020081373A1 (en) | 2018-10-16 | 2020-04-23 | Bard Access Systems, Inc. | Safety-equipped connection systems and methods thereof for establishing electrical connections |
USD968421S1 (en) | 2019-05-31 | 2022-11-01 | Biosense Webster (Israel) Ltd. | Display screen with a graphical user interface |
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US11957852B2 (en) | 2021-01-14 | 2024-04-16 | Biosense Webster (Israel) Ltd. | Intravascular balloon with slidable central irrigation tube |
Citations (96)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3268728A (en) * | 1964-03-03 | 1966-08-23 | Miles Lab | Apparatus and method for the determination of fluid volume by radioactive dilution techniques |
US3347224A (en) * | 1964-05-26 | 1967-10-17 | Brandon L Adams | Apparatus and method for measuring cardiac output |
US3516399A (en) * | 1967-04-18 | 1970-06-23 | Charles A Barefoot | Electromagnetic catheter blood flow probe |
US3604263A (en) * | 1968-01-31 | 1971-09-14 | Philips Corp | Device for measuring the flow intensity of circulating liquid |
US3651318A (en) * | 1970-01-26 | 1972-03-21 | Jan A Czekajewski | Cardiac output computer |
US3677648A (en) * | 1963-12-09 | 1972-07-18 | Johannes Dorsch | Method and apparatus for the measurement of dye dilution in blood |
US3757773A (en) * | 1972-03-22 | 1973-09-11 | Univ California | External field electromagnetic flow sensor-artery |
US3789831A (en) * | 1972-02-11 | 1974-02-05 | D Kopaniky | Thermoelectric probe apparatus for tissue fluid flow measurement |
US3835840A (en) * | 1973-09-27 | 1974-09-17 | Hope City | Impedance plethysmography method and apparatus |
US3835839A (en) * | 1972-12-08 | 1974-09-17 | Systron Donner Corp | Impedance plethysmograph and flow rate computer adjunct and method for use therewith |
US3896373A (en) * | 1972-11-30 | 1975-07-22 | Stein Paul D | Method and apparatus for determining cross-sectional area of a blood conduit and volumetric flow therethrough |
US4205688A (en) * | 1977-05-23 | 1980-06-03 | Doll Research, Inc. | Method and apparatus for developing and measuring pulsed blood flow |
US4212298A (en) * | 1977-10-20 | 1980-07-15 | Hart Associates, Inc. | Thermodilution injector |
US4217910A (en) * | 1978-10-10 | 1980-08-19 | The United States Of America As Represented By The Secretary Of The Navy | Internal jugular and left ventricular thermodilution catheter |
US4296754A (en) * | 1978-07-04 | 1981-10-27 | Hennig Ewald M C | Method for determining the value of cardiologic quantities and apparatus for performing said method |
US4314563A (en) * | 1970-09-24 | 1982-02-09 | The United States Of America As Represented By The Administrator Of The Veterans Administration | Apparatus for measuring relative changes in blood volume in a portion of an animal body to detect a venous occlusion |
US4450527A (en) * | 1982-06-29 | 1984-05-22 | Bomed Medical Mfg. Ltd. | Noninvasive continuous cardiac output monitor |
US4502488A (en) * | 1983-01-13 | 1985-03-05 | Allied Corporation | Injection system |
US4541433A (en) * | 1984-06-01 | 1985-09-17 | Medtronic, Inc. | Cardiac output monitor |
US4542748A (en) * | 1983-03-07 | 1985-09-24 | American Hospital Supply Corp. | Apparatus and method for measuring cardiac output |
US4572206A (en) * | 1982-04-21 | 1986-02-25 | Purdue Research Foundation | Method and apparatus for measuring cardiac output |
US4587975A (en) * | 1984-07-02 | 1986-05-13 | Cardiac Pacemakers, Inc. | Dimension sensitive angioplasty catheter |
US4595015A (en) * | 1983-04-12 | 1986-06-17 | Erasmus Universiteit Rotterdam | Method and apparatus for estimating the cardiac output of the heart of a patient |
US4610258A (en) * | 1984-11-13 | 1986-09-09 | General Electric Company | Method for calculating blood flow using freely diffusible inert gases and CT |
US4674518A (en) * | 1985-09-06 | 1987-06-23 | Cardiac Pacemakers, Inc. | Method and apparatus for measuring ventricular volume |
US4676253A (en) * | 1985-07-18 | 1987-06-30 | Doll Medical Research, Inc. | Method and apparatus for noninvasive determination of cardiac output |
US4685470A (en) * | 1984-11-21 | 1987-08-11 | Terumo Kabushiki Kaisha | Cardiac output measurement system and method |
US4730623A (en) * | 1985-06-14 | 1988-03-15 | Lee Arnold St J | Cardiac output estimation method and apparatus |
US4739771A (en) * | 1986-02-20 | 1988-04-26 | Kim Manwaring | Thermal method and apparatus for measuring organ blood perfusion |
US4802489A (en) * | 1986-07-29 | 1989-02-07 | Jerusalem College Of Technology | Method for carrying out blood flow measurements and a probe therefor |
US4811741A (en) * | 1985-02-27 | 1989-03-14 | See/Shell Biotechnology, Inc. | Volumetric determination of a fluid |
US4817624A (en) * | 1985-12-20 | 1989-04-04 | The General Hospital Corporation | Mini-bolus technique for thermodilution cardiac output measurements |
US4836214A (en) * | 1986-12-01 | 1989-06-06 | Bomed Medical Manufacturing, Ltd. | Esophageal electrode array for electrical bioimpedance measurement |
US4841981A (en) * | 1986-03-07 | 1989-06-27 | Terumo Corporation | Catheters for measurement of cardiac output and blood flow velocity |
US4852580A (en) * | 1986-09-17 | 1989-08-01 | Axiom Medical, Inc. | Catheter for measuring bioimpedance |
US4941475A (en) * | 1988-08-30 | 1990-07-17 | Spectramed, Inc. | Thermodilution by heat exchange |
US4953556A (en) * | 1984-12-13 | 1990-09-04 | Evans John M | Method and apparatus for the measurement of thoracic field potentiometry |
US4957110A (en) * | 1989-03-17 | 1990-09-18 | C. R. Bard, Inc. | Steerable guidewire having electrodes for measuring vessel cross-section and blood flow |
US5000190A (en) * | 1988-06-22 | 1991-03-19 | The Cleveland Clinic Foundation | Continuous cardiac output by impedance measurements in the heart |
US5009231A (en) * | 1986-03-18 | 1991-04-23 | Fa. Nattermann Arzneimittel Gmbh | Microprocessor controlled apparatus for the noninvasive determination of peripheral outflow and flow disturbances |
US5009234A (en) * | 1987-04-27 | 1991-04-23 | Eckhard Alt | For the thermodilution method of determining cardiac output |
US5014715A (en) * | 1988-11-22 | 1991-05-14 | Chapolini Robert J | Device for measuring the impedance to flow of a natural or prosthetic vessel in a living body |
US5046503A (en) * | 1989-04-26 | 1991-09-10 | Advanced Cardiovascular Systems, Inc. | Angioplasty autoperfusion catheter flow measurement method and apparatus |
US5058583A (en) * | 1990-07-13 | 1991-10-22 | Geddes Leslie A | Multiple monopolar system and method of measuring stroke volume of the heart |
US5080106A (en) * | 1989-01-13 | 1992-01-14 | Terumo Kabushiki Kaisha | Apparatus for measuring cardiac output |
USRE33834E (en) * | 1984-05-10 | 1992-03-03 | Sylvia Warner | Heart-related parameters monitoring apparatus |
US5092339A (en) * | 1990-07-23 | 1992-03-03 | Geddes Leslie A | Method and apparatus for electrically compensated measurement of cardiac output |
US5101828A (en) * | 1991-04-11 | 1992-04-07 | Rutgers, The State University Of Nj | Methods and apparatus for nonivasive monitoring of dynamic cardiac performance |
US5121749A (en) * | 1988-10-05 | 1992-06-16 | Cardiometrics, Inc. | Position in dependent volumetric flow measuring apparatus |
US5146414A (en) * | 1990-04-18 | 1992-09-08 | Interflo Medical, Inc. | Method and apparatus for continuously measuring volumetric flow |
US5176144A (en) * | 1989-09-14 | 1993-01-05 | Terumo Kabushiki Kaisha | Cardiac output measuring catheter |
US5178153A (en) * | 1984-03-08 | 1993-01-12 | Einzig Robert E | Fluid flow sensing apparatus for in vivo and industrial applications employing novel differential optical fiber pressure sensors |
US5183051A (en) * | 1991-01-14 | 1993-02-02 | Jonathan Kraidin | Means and apparatus for continuously determining cardiac output in a subject |
US5199438A (en) * | 1989-09-27 | 1993-04-06 | Atp Advanced Technologies Limited | Measurement of cardiac performance |
US5211177A (en) * | 1990-12-28 | 1993-05-18 | Regents Of The University Of Minnesota | Vascular impedance measurement instrument |
US5217019A (en) * | 1991-12-27 | 1993-06-08 | Abbott Laboratories | Apparatus and method for continuously monitoring cardiac output |
US5241965A (en) * | 1991-06-07 | 1993-09-07 | Mick Peter R | Cardiac monitor |
US5241966A (en) * | 1990-10-23 | 1993-09-07 | Hypertension Diagnostics, Inc. | Method and apparatus for measuring cardiac output |
US5277191A (en) * | 1991-06-19 | 1994-01-11 | Abbott Laboratories | Heated catheter for monitoring cardiac output |
US5289823A (en) * | 1992-05-12 | 1994-03-01 | Colin Electronics Co., Ltd. | Non-invasive aortic blood flow sensor and method for non-invasively measuring aortic blood flow |
US5291896A (en) * | 1991-08-21 | 1994-03-08 | Baxter International Inc. | Cardiac output probe assembly |
US5345932A (en) * | 1990-02-09 | 1994-09-13 | Minnesota Mining And Manufacturing Company | Method and system for monitoring of blood constituents in vivo |
US5346508A (en) * | 1993-04-29 | 1994-09-13 | Scimed Life Systems, Inc. | Apparatus and method for performing diagnostics and intravascular therapies |
US5354318A (en) * | 1993-04-30 | 1994-10-11 | Medtronic, Inc. | Method and apparatus for monitoring brain hemodynamics |
US5383468A (en) * | 1990-10-31 | 1995-01-24 | Nihon Kohden Corporation | Cardiac output and right ventricular ejection fraction system |
US5390679A (en) * | 1993-06-03 | 1995-02-21 | Eli Lilly And Company | Continuous cardiac output derived from the arterial pressure waveform using pattern recognition |
US5397308A (en) * | 1993-10-22 | 1995-03-14 | Scimed Life Systems, Inc. | Balloon inflation measurement apparatus |
US5400793A (en) * | 1991-01-29 | 1995-03-28 | Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno | Method of determining the stroke volume and the cardiac output of the human heart |
US5409009A (en) * | 1994-03-18 | 1995-04-25 | Medtronic, Inc. | Methods for measurement of arterial blood flow |
USRE34938E (en) * | 1990-06-28 | 1995-05-16 | Vladimir Serikov | Non-invasive method for measuring lung tissue volume and pulmonary blood flow and a probe to carry out the method |
US5423326A (en) * | 1991-09-12 | 1995-06-13 | Drexel University | Apparatus and method for measuring cardiac output |
US5423322A (en) * | 1988-12-29 | 1995-06-13 | Medical Physics, Inc. | Total compliance method and apparatus for noninvasive arterial blood pressure measurement |
US5439003A (en) * | 1993-12-16 | 1995-08-08 | Modern Technologies Corp. | Apparatus and method for measuring fluid flow |
US5443073A (en) * | 1991-09-12 | 1995-08-22 | Drexel University | System and method of impedance cardiography monitoring |
US5493100A (en) * | 1994-12-28 | 1996-02-20 | Pacesetter, Inc. | Thermistor flow sensor and related method |
US5494031A (en) * | 1991-03-25 | 1996-02-27 | Hoeft; Andreas | Apparatus and method for measuring cardiac output |
US5505204A (en) * | 1993-05-13 | 1996-04-09 | University Hospital (London) Development Corporation | Ultrasonic blood volume flow rate meter |
US5509424A (en) * | 1994-01-28 | 1996-04-23 | Aws Salim Nashef | Continuous cardiac output monitoring system |
US5515857A (en) * | 1993-07-09 | 1996-05-14 | Kabushiki Kaisha Toshiba | Ultrasonic diagnostic apparatus |
US5520190A (en) * | 1994-10-31 | 1996-05-28 | Ventritex, Inc. | Cardiac blood flow sensor and method |
US5595181A (en) * | 1994-03-24 | 1997-01-21 | Hubbard; A. Robert | System for providing cardiac output and shunt quantitation |
US5595182A (en) * | 1994-10-24 | 1997-01-21 | Transonic Systems, Inc. | Cardiovascular measurements by sound velocity dilution |
US5598841A (en) * | 1993-09-24 | 1997-02-04 | Kowa Company Ltd. | Blood flow measurement system |
US5617870A (en) * | 1993-04-29 | 1997-04-08 | Scimed Life Systems, Inc. | Intravascular flow measurement system |
US5636638A (en) * | 1994-06-29 | 1997-06-10 | Baxter International Inc. | Electrical power amplifier for continuous cardiac output monitoring |
US5706808A (en) * | 1995-01-31 | 1998-01-13 | Kleinerman; Marcos Y. | Fiber optic system for measuring cardiac output |
US5722415A (en) * | 1996-04-30 | 1998-03-03 | Medtronic, Inc. | Continuous cardiac output monitor |
US5722997A (en) * | 1996-09-17 | 1998-03-03 | Sulzer Intermedics Inc. | Method and apparatus for cardiac impedance sensing |
US5782774A (en) * | 1996-04-17 | 1998-07-21 | Imagyn Medical Technologies California, Inc. | Apparatus and method of bioelectrical impedance analysis of blood flow |
US5788647A (en) * | 1997-01-24 | 1998-08-04 | Eggers; Philip E. | Method, system and apparatus for evaluating hemodynamic parameters |
US5791349A (en) * | 1996-04-17 | 1998-08-11 | Urohealth, Inc. | Apparatus and method of bioelectrical impedance analysis of blood flow |
US5807258A (en) * | 1997-10-14 | 1998-09-15 | Cimochowski; George E. | Ultrasonic sensors for monitoring the condition of a vascular graft |
US5807269A (en) * | 1991-01-29 | 1998-09-15 | Baxter International Inc. | Thermodilution catheter having a safe, flexible heating element |
US6036654A (en) * | 1994-09-23 | 2000-03-14 | Baxter International Inc. | Multi-lumen, multi-parameter catheter |
US6053913A (en) * | 1998-09-10 | 2000-04-25 | Tu; Lily Chen | Rapid exchange stented balloon catheter having ablation capabilities |
US6986744B1 (en) * | 1999-02-02 | 2006-01-17 | Transonic Systems, Inc. | Method and apparatus for determining blood flow during a vascular corrective procedure |
Family Cites Families (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5033676A (en) | 1973-07-30 | 1975-03-31 | ||
US3996924A (en) | 1974-06-19 | 1976-12-14 | Wheeler H Brownell | Occlusive impedance phlebograph and method therefor |
US3996925A (en) | 1975-05-05 | 1976-12-14 | Ljubomir Djordjevich | System for determining characteristics of blood flow |
US3994284A (en) | 1975-12-31 | 1976-11-30 | Systron Donner Corporation | Flow rate computer adjunct for use with an impedance plethysmograph and method |
US4418700A (en) | 1981-03-11 | 1983-12-06 | Sylvia Warner | Method and apparatus for measurement of heart-related parameters |
US4484582A (en) | 1981-09-09 | 1984-11-27 | Memorial Hospital For Cancer & Allied Diseases | Electrolytic fluid flow rate method and apparatus |
US4576177A (en) * | 1983-02-18 | 1986-03-18 | Webster Wilton W Jr | Catheter for removing arteriosclerotic plaque |
US4621646A (en) | 1983-12-15 | 1986-11-11 | The United States Of America As Represented By The Secretary Of The Army | Blood flow measuring method |
US4632125A (en) | 1984-01-13 | 1986-12-30 | American Hospital Supply Corp. | Right heart ejection fraction and cardiac output catheter |
US4785823A (en) | 1987-07-21 | 1988-11-22 | Robert F. Shaw | Methods and apparatus for performing in vivo blood thermodilution procedures |
JPH02128753A (en) | 1988-11-09 | 1990-05-17 | Terumo Corp | Apparatus for measuring cardiac output |
JP2866132B2 (en) | 1990-01-29 | 1999-03-08 | テルモ株式会社 | Flow sensor probe |
US5271408A (en) | 1991-03-25 | 1993-12-21 | Siemens Elema Ab | Hydrodynamic system for blood flow measurement |
US5174299A (en) | 1991-08-12 | 1992-12-29 | Cardiac Pacemakers, Inc. | Thermocouple-based blood flow sensor |
DE69226371T2 (en) | 1991-11-08 | 1999-04-22 | Baxter Int | TRANSPORT CATHETER AND ULTRASONIC PROBE FOR USE WITH THE SAME |
US5368034A (en) * | 1992-09-04 | 1994-11-29 | Boston Scientific Corporation | Method and apparatus for thrombolytic therapy |
US5363856A (en) | 1993-08-13 | 1994-11-15 | Abbott Laboratories | Correcting thermal drift in cardiac output determination |
US5579778A (en) | 1993-09-09 | 1996-12-03 | University Of Utah Research Foundation | Method and apparatus for producing thermodilution cardiac output measurements utilizing a neural network |
US5566677A (en) | 1994-08-04 | 1996-10-22 | Raines; Jeffrey K. | Calibration of segmental blood changes in arteries and veins during detection of atherosclerosis |
-
1999
- 1999-02-02 US US09/241,455 patent/US6986744B1/en not_active Expired - Lifetime
-
2000
- 2000-02-02 EP EP00300807A patent/EP1025805A1/en not_active Withdrawn
- 2000-02-02 CA CA002297853A patent/CA2297853A1/en not_active Abandoned
-
2005
- 2005-03-25 US US11/089,797 patent/US20050171446A1/en not_active Abandoned
Patent Citations (100)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3677648A (en) * | 1963-12-09 | 1972-07-18 | Johannes Dorsch | Method and apparatus for the measurement of dye dilution in blood |
US3268728A (en) * | 1964-03-03 | 1966-08-23 | Miles Lab | Apparatus and method for the determination of fluid volume by radioactive dilution techniques |
US3347224A (en) * | 1964-05-26 | 1967-10-17 | Brandon L Adams | Apparatus and method for measuring cardiac output |
US3516399A (en) * | 1967-04-18 | 1970-06-23 | Charles A Barefoot | Electromagnetic catheter blood flow probe |
US3604263A (en) * | 1968-01-31 | 1971-09-14 | Philips Corp | Device for measuring the flow intensity of circulating liquid |
US3651318A (en) * | 1970-01-26 | 1972-03-21 | Jan A Czekajewski | Cardiac output computer |
US4314563A (en) * | 1970-09-24 | 1982-02-09 | The United States Of America As Represented By The Administrator Of The Veterans Administration | Apparatus for measuring relative changes in blood volume in a portion of an animal body to detect a venous occlusion |
US3789831A (en) * | 1972-02-11 | 1974-02-05 | D Kopaniky | Thermoelectric probe apparatus for tissue fluid flow measurement |
US3757773A (en) * | 1972-03-22 | 1973-09-11 | Univ California | External field electromagnetic flow sensor-artery |
US3896373A (en) * | 1972-11-30 | 1975-07-22 | Stein Paul D | Method and apparatus for determining cross-sectional area of a blood conduit and volumetric flow therethrough |
US3835839A (en) * | 1972-12-08 | 1974-09-17 | Systron Donner Corp | Impedance plethysmograph and flow rate computer adjunct and method for use therewith |
US3835840A (en) * | 1973-09-27 | 1974-09-17 | Hope City | Impedance plethysmography method and apparatus |
US4205688A (en) * | 1977-05-23 | 1980-06-03 | Doll Research, Inc. | Method and apparatus for developing and measuring pulsed blood flow |
US4212298A (en) * | 1977-10-20 | 1980-07-15 | Hart Associates, Inc. | Thermodilution injector |
US4296754A (en) * | 1978-07-04 | 1981-10-27 | Hennig Ewald M C | Method for determining the value of cardiologic quantities and apparatus for performing said method |
US4217910A (en) * | 1978-10-10 | 1980-08-19 | The United States Of America As Represented By The Secretary Of The Navy | Internal jugular and left ventricular thermodilution catheter |
US4572206B1 (en) * | 1982-04-21 | 1991-01-01 | Purdue Research Foundation | |
US4572206A (en) * | 1982-04-21 | 1986-02-25 | Purdue Research Foundation | Method and apparatus for measuring cardiac output |
US4450527A (en) * | 1982-06-29 | 1984-05-22 | Bomed Medical Mfg. Ltd. | Noninvasive continuous cardiac output monitor |
US4502488A (en) * | 1983-01-13 | 1985-03-05 | Allied Corporation | Injection system |
US4542748A (en) * | 1983-03-07 | 1985-09-24 | American Hospital Supply Corp. | Apparatus and method for measuring cardiac output |
US4595015A (en) * | 1983-04-12 | 1986-06-17 | Erasmus Universiteit Rotterdam | Method and apparatus for estimating the cardiac output of the heart of a patient |
US5178153A (en) * | 1984-03-08 | 1993-01-12 | Einzig Robert E | Fluid flow sensing apparatus for in vivo and industrial applications employing novel differential optical fiber pressure sensors |
USRE33834E (en) * | 1984-05-10 | 1992-03-03 | Sylvia Warner | Heart-related parameters monitoring apparatus |
US4541433A (en) * | 1984-06-01 | 1985-09-17 | Medtronic, Inc. | Cardiac output monitor |
US4587975A (en) * | 1984-07-02 | 1986-05-13 | Cardiac Pacemakers, Inc. | Dimension sensitive angioplasty catheter |
US4610258A (en) * | 1984-11-13 | 1986-09-09 | General Electric Company | Method for calculating blood flow using freely diffusible inert gases and CT |
US4685470A (en) * | 1984-11-21 | 1987-08-11 | Terumo Kabushiki Kaisha | Cardiac output measurement system and method |
US4953556A (en) * | 1984-12-13 | 1990-09-04 | Evans John M | Method and apparatus for the measurement of thoracic field potentiometry |
US4811741A (en) * | 1985-02-27 | 1989-03-14 | See/Shell Biotechnology, Inc. | Volumetric determination of a fluid |
US4730623A (en) * | 1985-06-14 | 1988-03-15 | Lee Arnold St J | Cardiac output estimation method and apparatus |
US4676253A (en) * | 1985-07-18 | 1987-06-30 | Doll Medical Research, Inc. | Method and apparatus for noninvasive determination of cardiac output |
US4674518A (en) * | 1985-09-06 | 1987-06-23 | Cardiac Pacemakers, Inc. | Method and apparatus for measuring ventricular volume |
US4817624A (en) * | 1985-12-20 | 1989-04-04 | The General Hospital Corporation | Mini-bolus technique for thermodilution cardiac output measurements |
US4739771A (en) * | 1986-02-20 | 1988-04-26 | Kim Manwaring | Thermal method and apparatus for measuring organ blood perfusion |
US4841981A (en) * | 1986-03-07 | 1989-06-27 | Terumo Corporation | Catheters for measurement of cardiac output and blood flow velocity |
US5009231A (en) * | 1986-03-18 | 1991-04-23 | Fa. Nattermann Arzneimittel Gmbh | Microprocessor controlled apparatus for the noninvasive determination of peripheral outflow and flow disturbances |
US4802489A (en) * | 1986-07-29 | 1989-02-07 | Jerusalem College Of Technology | Method for carrying out blood flow measurements and a probe therefor |
US4852580A (en) * | 1986-09-17 | 1989-08-01 | Axiom Medical, Inc. | Catheter for measuring bioimpedance |
US4836214A (en) * | 1986-12-01 | 1989-06-06 | Bomed Medical Manufacturing, Ltd. | Esophageal electrode array for electrical bioimpedance measurement |
US5009234A (en) * | 1987-04-27 | 1991-04-23 | Eckhard Alt | For the thermodilution method of determining cardiac output |
US5000190A (en) * | 1988-06-22 | 1991-03-19 | The Cleveland Clinic Foundation | Continuous cardiac output by impedance measurements in the heart |
US4941475A (en) * | 1988-08-30 | 1990-07-17 | Spectramed, Inc. | Thermodilution by heat exchange |
US5121749A (en) * | 1988-10-05 | 1992-06-16 | Cardiometrics, Inc. | Position in dependent volumetric flow measuring apparatus |
US5014715A (en) * | 1988-11-22 | 1991-05-14 | Chapolini Robert J | Device for measuring the impedance to flow of a natural or prosthetic vessel in a living body |
US5423322A (en) * | 1988-12-29 | 1995-06-13 | Medical Physics, Inc. | Total compliance method and apparatus for noninvasive arterial blood pressure measurement |
US5080106A (en) * | 1989-01-13 | 1992-01-14 | Terumo Kabushiki Kaisha | Apparatus for measuring cardiac output |
US4957110A (en) * | 1989-03-17 | 1990-09-18 | C. R. Bard, Inc. | Steerable guidewire having electrodes for measuring vessel cross-section and blood flow |
US5046503A (en) * | 1989-04-26 | 1991-09-10 | Advanced Cardiovascular Systems, Inc. | Angioplasty autoperfusion catheter flow measurement method and apparatus |
US5176144A (en) * | 1989-09-14 | 1993-01-05 | Terumo Kabushiki Kaisha | Cardiac output measuring catheter |
US5199438A (en) * | 1989-09-27 | 1993-04-06 | Atp Advanced Technologies Limited | Measurement of cardiac performance |
US5345932A (en) * | 1990-02-09 | 1994-09-13 | Minnesota Mining And Manufacturing Company | Method and system for monitoring of blood constituents in vivo |
US5146414A (en) * | 1990-04-18 | 1992-09-08 | Interflo Medical, Inc. | Method and apparatus for continuously measuring volumetric flow |
USRE34938E (en) * | 1990-06-28 | 1995-05-16 | Vladimir Serikov | Non-invasive method for measuring lung tissue volume and pulmonary blood flow and a probe to carry out the method |
US5058583A (en) * | 1990-07-13 | 1991-10-22 | Geddes Leslie A | Multiple monopolar system and method of measuring stroke volume of the heart |
US5092339A (en) * | 1990-07-23 | 1992-03-03 | Geddes Leslie A | Method and apparatus for electrically compensated measurement of cardiac output |
US5241966A (en) * | 1990-10-23 | 1993-09-07 | Hypertension Diagnostics, Inc. | Method and apparatus for measuring cardiac output |
US5383468A (en) * | 1990-10-31 | 1995-01-24 | Nihon Kohden Corporation | Cardiac output and right ventricular ejection fraction system |
US5316004A (en) * | 1990-12-28 | 1994-05-31 | Regents Of The University Of Minnesota | Method for vascular impedance measurement |
US5211177A (en) * | 1990-12-28 | 1993-05-18 | Regents Of The University Of Minnesota | Vascular impedance measurement instrument |
US5183051A (en) * | 1991-01-14 | 1993-02-02 | Jonathan Kraidin | Means and apparatus for continuously determining cardiac output in a subject |
US5400793A (en) * | 1991-01-29 | 1995-03-28 | Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno | Method of determining the stroke volume and the cardiac output of the human heart |
US5807269A (en) * | 1991-01-29 | 1998-09-15 | Baxter International Inc. | Thermodilution catheter having a safe, flexible heating element |
US5494031A (en) * | 1991-03-25 | 1996-02-27 | Hoeft; Andreas | Apparatus and method for measuring cardiac output |
US5101828A (en) * | 1991-04-11 | 1992-04-07 | Rutgers, The State University Of Nj | Methods and apparatus for nonivasive monitoring of dynamic cardiac performance |
US5241965A (en) * | 1991-06-07 | 1993-09-07 | Mick Peter R | Cardiac monitor |
US5277191A (en) * | 1991-06-19 | 1994-01-11 | Abbott Laboratories | Heated catheter for monitoring cardiac output |
US5291896A (en) * | 1991-08-21 | 1994-03-08 | Baxter International Inc. | Cardiac output probe assembly |
US5443073A (en) * | 1991-09-12 | 1995-08-22 | Drexel University | System and method of impedance cardiography monitoring |
US5423326A (en) * | 1991-09-12 | 1995-06-13 | Drexel University | Apparatus and method for measuring cardiac output |
US5217019A (en) * | 1991-12-27 | 1993-06-08 | Abbott Laboratories | Apparatus and method for continuously monitoring cardiac output |
US5289823A (en) * | 1992-05-12 | 1994-03-01 | Colin Electronics Co., Ltd. | Non-invasive aortic blood flow sensor and method for non-invasively measuring aortic blood flow |
US5346508A (en) * | 1993-04-29 | 1994-09-13 | Scimed Life Systems, Inc. | Apparatus and method for performing diagnostics and intravascular therapies |
US5617870A (en) * | 1993-04-29 | 1997-04-08 | Scimed Life Systems, Inc. | Intravascular flow measurement system |
US5354318A (en) * | 1993-04-30 | 1994-10-11 | Medtronic, Inc. | Method and apparatus for monitoring brain hemodynamics |
US5505204A (en) * | 1993-05-13 | 1996-04-09 | University Hospital (London) Development Corporation | Ultrasonic blood volume flow rate meter |
US5797395A (en) * | 1993-06-03 | 1998-08-25 | Eli Lilly And Company | Continuous cardiac output derived from arterial pressure waveform using pattern recognition |
US5390679A (en) * | 1993-06-03 | 1995-02-21 | Eli Lilly And Company | Continuous cardiac output derived from the arterial pressure waveform using pattern recognition |
US5515857A (en) * | 1993-07-09 | 1996-05-14 | Kabushiki Kaisha Toshiba | Ultrasonic diagnostic apparatus |
US5598841A (en) * | 1993-09-24 | 1997-02-04 | Kowa Company Ltd. | Blood flow measurement system |
US5397308A (en) * | 1993-10-22 | 1995-03-14 | Scimed Life Systems, Inc. | Balloon inflation measurement apparatus |
US5724982A (en) * | 1993-12-16 | 1998-03-10 | Modern Technologies Corp. | Apparatus and method for measuring fluid flow |
US5439003A (en) * | 1993-12-16 | 1995-08-08 | Modern Technologies Corp. | Apparatus and method for measuring fluid flow |
US5509424A (en) * | 1994-01-28 | 1996-04-23 | Aws Salim Nashef | Continuous cardiac output monitoring system |
US5409009A (en) * | 1994-03-18 | 1995-04-25 | Medtronic, Inc. | Methods for measurement of arterial blood flow |
US5595181A (en) * | 1994-03-24 | 1997-01-21 | Hubbard; A. Robert | System for providing cardiac output and shunt quantitation |
US5636638A (en) * | 1994-06-29 | 1997-06-10 | Baxter International Inc. | Electrical power amplifier for continuous cardiac output monitoring |
US6036654A (en) * | 1994-09-23 | 2000-03-14 | Baxter International Inc. | Multi-lumen, multi-parameter catheter |
US5595182A (en) * | 1994-10-24 | 1997-01-21 | Transonic Systems, Inc. | Cardiovascular measurements by sound velocity dilution |
US5520190A (en) * | 1994-10-31 | 1996-05-28 | Ventritex, Inc. | Cardiac blood flow sensor and method |
US5493100A (en) * | 1994-12-28 | 1996-02-20 | Pacesetter, Inc. | Thermistor flow sensor and related method |
US5706808A (en) * | 1995-01-31 | 1998-01-13 | Kleinerman; Marcos Y. | Fiber optic system for measuring cardiac output |
US5782774A (en) * | 1996-04-17 | 1998-07-21 | Imagyn Medical Technologies California, Inc. | Apparatus and method of bioelectrical impedance analysis of blood flow |
US5791349A (en) * | 1996-04-17 | 1998-08-11 | Urohealth, Inc. | Apparatus and method of bioelectrical impedance analysis of blood flow |
US5722415A (en) * | 1996-04-30 | 1998-03-03 | Medtronic, Inc. | Continuous cardiac output monitor |
US5722997A (en) * | 1996-09-17 | 1998-03-03 | Sulzer Intermedics Inc. | Method and apparatus for cardiac impedance sensing |
US5788647A (en) * | 1997-01-24 | 1998-08-04 | Eggers; Philip E. | Method, system and apparatus for evaluating hemodynamic parameters |
US5807258A (en) * | 1997-10-14 | 1998-09-15 | Cimochowski; George E. | Ultrasonic sensors for monitoring the condition of a vascular graft |
US6053913A (en) * | 1998-09-10 | 2000-04-25 | Tu; Lily Chen | Rapid exchange stented balloon catheter having ablation capabilities |
US6986744B1 (en) * | 1999-02-02 | 2006-01-17 | Transonic Systems, Inc. | Method and apparatus for determining blood flow during a vascular corrective procedure |
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US20150173948A1 (en) * | 2013-12-20 | 2015-06-25 | Alcon Research, Ltd. | Tissue-Sensing Vitrectomy Surgical Systems and Methods |
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US11330990B2 (en) * | 2015-01-05 | 2022-05-17 | Nipro Corporation | Blood flow meter and measurement device |
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EP1025805A1 (en) | 2000-08-09 |
CA2297853A1 (en) | 2000-08-02 |
US6986744B1 (en) | 2006-01-17 |
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