The Wallgraft Endoprosthesis (stent graft) consists of a metallic stent comprised of biomedical superalloy monofilament wire with a radiopaque core, braided in a tubular mesh configuration. A platinum nickel micro-cable is incorporated into the stent to enhance radiopacity of the device. A graft material comprised of braided polyester varn (PET) is adhesively bonded to the outside of the metallic stent. This design configuration results in a stent graft that is flexible, compliant, and self-expanding with the barrier characteristics of a tubular graft.

The Unistep Plus Delivery System consists of a coaxial tube system. The exterior tube serves to constrain the stent graft over the interior tube until retracted during deployment. The coaxial tubes have the capability of re-constraining the stent graft after partial deployment. A holding sleeve and stent cup, attached to the interior tube, aid in the re-constraining process.

Radiopaque marker bands situated adjacent to the proximal and distal ends of the stent graft facilitate imaging during deployment. A radiopaque marker band located on the exterior tube and a limit marker band on the interior tube function as deployment limit markers. Re-constrainment is possible up to the point where the exterior tube marker band is proximally retracted to the location of the interior tube limit marker.

The interior tube of the coaxial system contains a central lumen which will accommodate a 0.035" guide wire. The delivery system will be available in a single working length of 90 cm.

AI/ML Overview

The document provided is a 510(k) summary for the WALLGRAFT® Tracheobronchial Endoprosthesis with Unistep™ Plus Delivery System. It describes the device, its intended use, and a summary of performance testing conducted to demonstrate substantial equivalence to previously cleared predicate devices.

Here's an analysis of the acceptance criteria and study information, based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state numerical acceptance criteria for each test. Instead, it states that "All test results verified that the modified 9 F - 11 F delivery system is adequate for its intended use." This implies that the observed performance met internal company specifications or expected performance characteristics for such devices.

Test Performed	Reported Device Performance
Total Catheter Length	Verified adequacy for intended use
Catheter Crossing Profile	Verified adequacy for intended use
Deployment Force	Verified adequacy for intended use
Reconstrainment Force	Verified adequacy for intended use
Stent Graft Securement	Verified adequacy for intended use
Hub to Stainless Steel Tube Tensile	Verified adequacy for intended use
Distal Tip Tensile	Verified adequacy for intended use
Inner Member Assembly Tensile	Verified adequacy for intended use
Valve Body to Exterior Tube Tensile	Verified adequacy for intended use
Deployed Stent Graft OD Post Accelerated Aging Testing	Verified adequacy for intended use
Biocompatibility	Verified adequacy for intended use

2. Sample size used for the test set and the data provenance

The document does not specify the sample sizes used for each test.
The data provenance is internal testing conducted by Boston Scientific Corporation. The country of origin of the data is not specified, but the submitter's address is in Maple Grove, Minnesota, USA. The testing appears to be prospective, performed specifically for this 510(k) submission to demonstrate the modified device's performance.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts

This section is not applicable. The study described involves performance testing of a medical device (mechanical, material, and biocompatibility testing), not a diagnostic or prognostic medical AI algorithm that requires expert-established ground truth.

4. Adjudication method for the test set

This section is not applicable. Adjudication methods like 2+1 or 3+1 are typically used in studies involving human interpretation or clinical endpoints, not for engineering performance testing of a device.

5. If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

This section is not applicable. The submission is for a medical device (stent graft and delivery system), not an AI algorithm. Therefore, no MRMC study or assessment of AI assistance for human readers was performed or reported.

6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done

This section is not applicable. As stated above, this submission is for a medical device, not an AI algorithm.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)

This section is not applicable in the traditional sense of clinical ground truth. For the engineering performance tests, the "ground truth" would be the engineering specifications and established test methodologies (e.g., tensile strength required per standard, dimensional tolerances). The "truth" is whether the device meets these pre-defined performance metrics.

8. The sample size for the training set

This section is not applicable. The submission details performance testing of a physical medical device, not an AI algorithm that requires a training set.

9. How the ground truth for the training set was established

This section is not applicable for the same reason as point 8.

Summary

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Image /page/0/Picture/1 description: The image shows the seal of the Department of Health and Human Services (HHS). The seal features an abstract image of an eagle with three lines forming its body and wings. The words "DEPARTMENT OF HEALTH AND HUMAN SERVICES, USA" are arranged in a circular pattern around the eagle.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

NOV - 3 2006

Boston Scientific Corporation % Ms. Angela Byland Manager, Regulatory Affairs Cardiovascular Two Scimed Place Maple Grove, Minnesota 55311-1566

Re: K021901

Trade/Device Name: Wallgraft® Tracheobronchial Endoprosthesis with Unistep Plus Delivery System

Regulation Number: 21 CFR 878.3720 Regulation Name: Tracheal prosthesis Regulatory Class: II Product Code: JCT Dated: June 7, 2002 Received: June 10, 2002

Dear Ms. Byland:

This letter corrects our substantially equivalent letter of July 9, 2002.

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and 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) that do not require approval of a premarket approval (PMA). 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 (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set

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Page 2 - Ms. Angela Byland

forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (sections 531-542 of the Act); 21 CFR 1000-1050.

This letter will allow you to continue marketing your device as described in your Section 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), please contact the Office of Compliance at (240) 276-0115. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (240) 276-3150 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html

Sincerely vours.

Herbert Lehman

Mark N. Melkerson Director Division of General, Restorative and Neurological Devices Office of Device Evaluation Center for Devices and Radiological Health

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Indications for Use Statement

510(k) Number (if known)	K021901
Device Name	WALLGRAFT® Tracheobronchial Endoprosthesis with Unistep™ Plus Delivery System
Indications For Use	The WALLGRAFT® Tracheobronchial Endoprosthesis is indicated for use in the treatment of tracheobronchial strictures produced by malignant neoplasms.

Prescription Use:_____________________________________________________________________________________________________________________________________________________________ × (Per 21 CFR §801 Subpart D) OR

Over-The-Counter Use: (21 CFR 807 Subpart C)

(PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Huld Lume

(Division Sign-Off) Division of General, Restorative, and Neurological Devices

510(k) Number $\underline{K_{02}(90)}$

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K021901 p. lot 3

510(k) Summary

Submitter'sName andAddress	Boston Scientific CorporationOne Scimed PlaceMaple Grove, MN 55311
Contact Nameand Information	Angela BylandManager, Regulatory AffairsPhone: 763-494-2887Fax: 763-494-2981e-mail: bylanda@bsci.com
Original DatePrepared	June 7, 2002
Date Prepared	July 14, 2006
ProprietaryName(s)	WALLGRAFT® Tracheobronchial Endoprosthesis withUnistep™ Plus Delivery System
Common Name	Tracheal Endoprosthesis
Product Code	JCT
Classification ofDevice	Class II, 21 CFR Part 878.3720
Predicate Device	WALLGRAFT®TracheobronchialEndoprosthesiswith Unistep™Delivery System	K000001	June 5, 2005
	WALLGRAFT®TracheobronchialEndoprosthesiswith Unistep™Delivery System	K003100	December 20, 2000

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K021901 f. 2 of 3

Image /page/4/Picture/1 description: The image shows the logo for Boston Scientific. The words "Boston" and "Scientific" are stacked on top of each other. The font is a serif font and the text is black.

Device Description

The Wallgraft Endoprosthesis with Unistep Plus Delivery System is available in the models indicated in the table below.

A brief description of the stent graft and delivery system components follow.

Stent GraftDiameter	Stent Graft Length	Delivery SystemProfile
6.0 mm	20 mm, 30 mm, 50 mm, 70 mm	9F
7.0 mm	20 mm, 30 mm, 50 mm, 70 mm	9F
8.0 mm	20 mm, 30 mm, 50 mm, 70 mm	9F
9.0 mm	20 mm, 30 mm, 50 mm, 70 mm	10F
10.0 mm	20 mm, 30 mm, 50 mm, 70 mm	10F
12.0 mm	30 mm, 50 mm, 70 mm	11F
14.0 mm	50 mm, 70 mm	12F

Stent Graft Description

Delivery System Description

The interior tube of the coaxial system contains a central lumen which will accommodate a 0.035" guide wire. The delivery system will be available in a single working length of 90 cm.

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021901 p. 3 of 3

Intended Use	The WALLGRAFT® Tracheobronchial Endoprosthesis isindicated for use in the treatment of tracheobronchialstrictures produced by malignant neoplasms.
TechnologicalCharacteristics	The modified 9 F - 11 F Unistep Plus Delivery System of the6 mm to 12 mm Wallgraft Endoprosthesis will bemanufactured in a substantially equivalent manner to thecurrently marketed 12 F delivery system of the 14 mmWallgraft Tracheobronchial Endoprosthesis with UnistepPlus Delivery System, cleared to market under K003100,December 20, 2000.
PerformanceTesting	Testing was conducted to verify that the modified 9 F - 11 Fdelivery system met product specifications. The followingtesting was performed:Total Catheter Length Catheter Crossing Profile Deployment Force Reconstrainment Force Stent Graft Securement Hub to Stainless Steel Tube Tensile Distal Tip Tensile Inner Member Assembly Tensile Valve Body to Exterior Tube Tensile Deployed Stent Graft OD Post Accelerated Aging Testing Biocompatibility All test results verified that the modified 9 F - 11 F deliverysystem is adequate for its intended use. The modifieddevice is considered substantially equivalent to the currentlymarketed 9 F - 11 F delivery system (K000001) and the 12F delivery system (K003100).
Conclusion	In summary, Boston Scientific Corporation hasdemonstrated that the WALLGRAFT® TracheobronchialEndoprosthesis with Unistep™ Plus Delivery System issubstantially equivalent based on design, test results, andindications for use to the predicate devices.

Regulation Number and Section

§ 878.3720 Tracheal prosthesis.

(a)
Identification. The tracheal prosthesis is a rigid, flexible, or expandable tubular device made of a silicone, metal, or polymeric material that is intended to be implanted to restore the structure and/or function of the trachea or trachealbronchial tree. It may be unbranched or contain one or two branches. The metal tracheal prosthesis may be uncovered or covered with a polymeric material. This device may also include a device delivery system.(b)
Classification. Class II. The special control for this device is FDA's “Guidance for the Content of Premarket Notification Submissions for Esophageal and Tracheal Prostheses.”