RADII DIAGNOSTIC ELECTROPHYSIOLOGY CATHETER, MODEL # 30411 B, C AND D
Applicant
Cardiac Pathways Corp.
Product Code
DRF · Cardiovascular
Decision Date
Dec 22, 1998
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 870.1220
Device Class
Class 2
Indications for Use
The Radii Diagnostic Electrophysiology Catheter is intended to be used to record intracardiac electrogram (EGM) signals and to deliver pacing pulses for the purpose of diagnostic provocative stimulation during an electrophysiology procedure.
Device Story
Radii Diagnostic Electrophysiology Catheter is 7 F steerable, deflectable, quadrapolar catheter; features 4 mm tip electrode and three 1 mm ring electrodes; handle-controlled pull-wire mechanism enables tip deflection and straightening; catheter shaft includes braiding for rotational force transmission. Device connects to external electrophysiologic recorders and pacing stimulators via specialized EGM and pacing cables; pin adaptors provided for stimulator compatibility. Used in clinical electrophysiology procedures by physicians to record intracardiac signals and deliver pacing pulses for diagnostic provocative stimulation. Output consists of electrical signals displayed on external recorders; clinical decision-making relies on physician interpretation of these electrograms to diagnose cardiac arrhythmias.
Clinical Evidence
Bench testing only. No clinical data provided. Testing included electrical assessments (continuity, short circuits, DC/AC impedance, capacitance, dielectric strength, current leakage) and mechanical assessments (joint strength, deflection durability). Biocompatibility testing performed.
Technological Characteristics
7 F steerable, deflectable, quadrapolar catheter; 4 mm tip electrode, three 1 mm ring electrodes; shaft features braided tubing for torque transmission; two lumens (electrode wires, pull-wire); handle-based deflection mechanism; connectivity via proprietary EGM/pacing cables and pin adaptors; non-implantable; manual operation.
Indications for Use
Indicated for patients undergoing electrophysiology procedures requiring intracardiac electrogram recording and diagnostic provocative pacing stimulation.
Regulatory Classification
Identification
An electrode recording catheter or an electrode recording probe is a device used to detect an intracardiac electrocardiogram, or to detect cardiac output or left-to-right heart shunts. The device may be unipolar or multipolar for electrocardiogram detection, or may be a platinum-tipped catheter which senses the presence of a special indicator for cardiac output or left-to-right heart shunt determinations.
Diagnostic/Ablation Large & Grooved Dome Delectable Catheters (Webster Laboratories)
Submission Summary (Full Text)
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CARDIAC PATHWAYS CORPORATION Premarket Notification
# 510(k) SUMMARY
#### Indications
The Radii Diagnostic Electrophysiology Catheter is intended to be used to record intracardiac electrogram (EGM) signals and to deliver pacing pulses for the purpose of diagnostic provocative stimulation during an electrophysiology procedure.
Radii Diagnostic Electrophysiolog
Catheter
### Device Description
The Radii Diagnostic Electrophysiology Catheter is a 7 F steerable, deflectable, quadrapolar catheter. It has a 4 mm tip electrode and three 1 mm ring electrodes in the flexible distal tip and a handle at the proximal end. The catheter is available in several curve sizes, two shaft stiffnesses, and two electrode spacings. Figure 1, depicts the basic configuration of the catheter.
Image /page/0/Figure/7 description: The image shows a diagram of a medical instrument, possibly an endoscope or catheter, with a handle and a long, flexible tube. The tube is bent at a 90-degree angle, and a measurement of "120 cm" is indicated near the bend, suggesting the length of the curved section. The instrument appears to be designed for insertion into the body, with the flexible tube allowing it to navigate through internal passages.
Figure 1: Radii Catheter
The four electrodes at the distal end of the catheter include one 4 mm electrode at the distal tip, and three 1 mm ring electrodes placed at specified distances proximal to the tip electrode. One interelectrode spacing configuration is 2 mm, 5 mm, and 2 mm (2,5,2) and the other interelectrode spacing configuration is 2 mm, 2 mm, and 2 mm (2,2,2). Each of the electrodes is attached to a conductor that extends from the electrode to a specific pin in the connector in the handle.
Image /page/0/Figure/10 description: The image shows a diagram of a cylindrical object with several labeled dimensions. There are three shaded regions along the cylinder, each separated by a distance. The dimensions provided are 1mm, 2mm, 4mm, and 5mm.
Figure 2: Distal Tip: 2,5,2 interelectrode spacing configuration
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The shaft has two lumens, one for the electrode wires and the other for the pull-wire. To facilitate the transmission of rotational force, the shaft includes braiding sandwiched between layers of tubing.
At the proximal end of the handle (i.e., farthest from the shaft), there is a connector for connecting the device to an external stimulator and electrophysiologic recorder. The knob utilized to deflect the tip is on the distal end of the handle (i.e., nearest to the shaft). This knob is connected to the tip by the pull-wire.
Pulling the knob toward the connector causes the tip to deflect, with the extent of deflection controlled by the extent of movement of the knob. Pushing the knob toward the shaft causes the tip to straighten. Rotating the handle to the right rotates the catheter tip counterclockwise or clockwise, respectively (as viewed from the handle).
Figure 3 depicts the movement of the catheter tip in three-dimensional space.
Image /page/1/Figure/6 description: This image shows a 3D coordinate system with the X, Y, and Z axes labeled. A curve is shown in the Z direction, labeled as a catheter tip, and it is noted that it goes from 0 to 270 degrees. The rotation is shown in the Y direction, and it is noted that it goes from 0 to 360 degrees.
Figure 3: Radii Tip Movement in Three Dimensional Space
## Cables
The Radii Catheter connects to an electrophysiologic recorder using an EGM Cable designed specifically for the connector configuration on the recorder. Each cable has a connector on one end that mates to the connector on the Radii Catheter and a connector on the other end that mates to the recorder. Within the insulated cable bundle, each conductor is insulated.
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Image /page/2/Figure/2 description: The image shows three different cable models with their specifications. The first cable is the Model 2001 EGM Cable, which is 96 inches long with a tolerance of plus or minus 4 inches and has a 6-pin plug on each end. The second cable is the Model 2028 EGM Cable, which is 36 inches long with a tolerance of plus or minus 4 inches and also has a 6-pin plug on each end. The third cable has a 6-pin plug on one end and a DIN 42802 protected socket on the other end, with a length of 96 inches plus or minus 4 inches to the start of the socket, then 5 inches plus or minus 1 inch to the start of the pins, and finally 1.52 inches to the end of the pins.
Image /page/2/Figure/3 description: The image shows the text "Model 2002 EGM Cable". The text is written in a simple, sans-serif font and is horizontally aligned. The text appears to be a label or identifier for a product, possibly a cable.
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Image /page/3/Figure/2 description: The image shows a technical drawing of a cable assembly. The cable has a 6-pin plug on one end and four DIN 42802 protected sockets on the other end. The cable is 36 inches long, plus or minus 4 inches. The length from the split to the sockets is 5 inches, plus or minus 1 inch, and the length of the socket is 1.52 inches.
#### Model 2029 EGM Cable
Figure 4: EGM Cables
A separate cable is utilized for connecting the Radii Catheter to an external stimulator. Like the EGM Cables, this cable has a connector on one end that mates to the connector on the Radii Catheter and a connector on the other end that mates to the stimulator. Each conductor within the insulated cable bundle is insulated. Because many pacing stimulators do not contain protected-pin attachments (these are designed into the Cardiac Pathways cable), a Pin Adaptor is provided with the cable to allow for a variety of connection situations. This pin adaptor is also pictured below.
Pacing Stimulator Cable
Image /page/3/Figure/7 description: The image shows a diagram of a cable with connectors on both ends. On the left side, there are two protected pin connectors. The cable has a total length of 12 1/2 feet and on the right side, there is a quick disconnect circular connector.
Image /page/3/Figure/8 description: The image shows the text "Model 2039 Pacing Stimulator Cable". The text is in a sans-serif font and is black. The background is white. The text is centered in the image.
Pin Adaptor (approximately 1 1/8 inch long)
Image /page/3/Figure/10 description: The image is a technical drawing of a cylindrical object. The object appears to be composed of several sections with varying diameters. Dashed lines within the drawing indicate internal features or hidden edges of the object.
Figure 5: Pacing Stimulator Cable
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### Predicate Devices
The Radii Diagnostic Electrophysiology Catheter is substantially equivalent to the Polaris–Dx™ Steerable Diagnostic Catheter and the EPT–Dx™ manufactured by EP Technologies, and Diagnostic/Ablation Large & Grooved Dome Delectable Catheters manufactured by Webster Laboratories.
## Performance Data
The Radii Diagnostic Electrophysiology Catheter, the EGM Cables, and the Pacing Stimulator Cable were subjected to a battery of electrical and mechanical tests to verify that the devices met the specifications. Electrical testing included, but was not limited to. assessment for continuity and short circuits, DC impedance, AC impedance, capacitance, and dielectric strength and current leakage. The device met the specifications. Mechanical testing included, but was not limited to, assessment of joint strengths and the ability to withstand multiple deflections. The device met the specifications. Biocompatibility testing was performed to verify that the devices did not elicit toxicological responses.
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Image /page/5/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo features a stylized image of an eagle with three human profiles incorporated into its design. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" is arranged in a circular pattern around the eagle.
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
DEC 2 2 1998
Ms. Erin Dignan Manager, Regulatory Affairs Cardiac Pathways Corporation 995 Benecia Avenue Sunnyvale, CA 94086
Re: K983653 Radii Diagnostic Electrophysiology Catheter Requlatory Class: II (two) Product Code: DRF Dated: October 16, 1998 Received: October 19, 1998
Dear Ms. Dignan:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.
If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Requlations, Title 21, Parts 800 A substantially equivalent determination assumes compliance to 895. with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any
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obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.
This letter will allow you to begin marketing your device as described in your 510 (k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4648. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, 2Misbranding by reference to premarket notification? (21CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its internet address "http://www.fda.qov/cdrh/dsma/dsmamain.html".
Sincerely yours,
Thomas J. Callahan, Ph.D.
Director Division of Cardiovascular, Respiratory, and Neurological Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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Page 1 of 1 -
510(k) Number: K983653
Device Name: Cardiac Pathways Corp., Radii Diagnostic Electrophysiologic Catheter
Indications For Use:
The Radii Diagnostic Electrophysiologic Catheter is intended to be used to record . intracardiac electrogram (EGM) signals and to deliver pacing pulses for the purpose of diagnostic provocative stimulation during an electrophysiology procedure.
(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
Prescription Use X (Per 21 CFR 801.109) OR
Over-The-Counter Use _________________________________________________________________________________________________________________________________________________________
(Optional Format 1-2-96)
N. Oadly Willin
iovascular. Respiratory.
**510(k) Number** K983653
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