(5 days)
The Uni-Graft K DV is indicated for use in repair or replacement of damaged and diseased vessels of the abdomen in cases of aneurysmal or occlusive disease.
This device is a vascular graft intended for use as a replacement conduit for abdominal, thoracic, and larger peripheral arterial reconstruction. It is a polyester terephthalate knitted fiber graft coated with modified cross linked gelatin to establish zero porosity or leakage through the wall.
Here's an analysis of the provided text regarding the Uni-graft® K DV Vascular Graft, focusing on acceptance criteria and supporting studies:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Preamble/Background: | |
| Replacement conduit for abdominal, thoracic, and larger peripheral arterial reconstruction due to aneurysmal or occlusive disease. | The device is a "replacement conduit for abdominal, thoracic, and larger peripheral arterial reconstruction." Its purpose is to address "aneurysmal disease or potential rupture, and occlusive disease or blockage of the natural vessel." |
| Material/Composition: | |
| Polyester terephthalate knitted fiber graft coated with modified cross-linked gelatin to establish zero porosity or leakage. | "It is a polyester terephthalate knitted fiber graft coated with modified cross linked gelatin to establish zero porosity or leakage through the wall." |
| Functional Benefit (coated graft): | |
| Does not require preclotting. | |
| Minimizes blood loss. | |
| Minimizes operative time. | |
| Minimizes substitute blood product exposure. | |
| Minimizes anesthesia. | "The benefits of a gelatin coated product as a vascular replacement are significant in that it does not require preclotting, minimizes blood loss, operative time, substitute blood product exposure, and anesthesia." |
| Safety (Risk Profile): | |
| No increase in risk over an uncoated polyester prosthesis. | |
| No increase in complications specifically associated with the Uni-graft prosthesis (bleeding, negative collagen antibody testing). | "Patients undergoing implantation of the Uni-graft® K DV experience no increase in any risk over that of an uncoated polyester prosthesis based upon study results or implantation history of this product in the world marketplace." |
| "This clinical study showed no bleeding, negative collagen antibody testing or complications specifically associated with the Uni-graft® prosthesis at the 6 month study period." | |
| Structural Integrity/Stability: | |
| Equivalent strength to existing devices. | |
| Long-term structural stability. | "All pertinent structural and biological testing such as burst strength, compliance, etc., parameters detailed in the Vascular graft prostheses guidance and tripartite documents have been completed. The results show equivalent strength and long term structural stability of this product compared to existing devices." |
| Effectiveness (Patency Rate): | |
| High cumulative patency rate. | "The cumulative patency rate was 98.8%." |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: The clinical study mentioned involved 100 patients.
- Data Provenance: The study was conducted in Japan from 1990 - 1993. This is prospective data, as it describes a clinical trial designed to collect new information.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
The provided text does not explicitly state the number of experts used to establish ground truth in the Japanese clinical study. It also does not specify their qualifications. The results (e.g., patency rate, absence of complications) would have been assessed by the medical professionals involved in the study (surgeons, other clinicians), but the process for establishing a definitive "ground truth" (e.g., adjudicated outcomes) is not detailed.
4. Adjudication Method for the Test Set
The document does not specify an adjudication method (e.g., 2+1, 3+1, none) for the clinical study's outcomes.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and Effect Size
No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done, nor would it be applicable in this context. This device is a physical vascular graft, not an AI diagnostic tool that human readers would interpret. The studies described are assessing the performance of the device itself in vivo.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
No, a standalone "algorithm only" performance study was not done. This device is a medical implant, not a software algorithm.
7. The Type of Ground Truth Used
For the clinical study on 100 patients, the ground truth was based on clinical outcomes data. This includes:
- Observation of complications (bleeding, immunological reactions, etc.)
- Results of collagen antibody testing
- Measurement of cumulative patency rate
These are objective clinical assessments and measurements rather than expert consensus on images or pathology samples.
8. The Sample Size for the Training Set
The document mentions "Over 200,000 implants worldwide" of the Uni-graft® product with an "exemplary record of success." This vast number of implants represents a significant body of real-world experience and historical data that would have informed the development and validation of the device, essentially acting as a broad "training set" of observational data prior to the specific 100-patient clinical study. However, it's not a formally defined "training set" in the context of an AI algorithm.
9. How the Ground Truth for the Training Set Was Established
For the "over 200,000 implants worldwide," the ground truth was established through implantation history and patient outcomes observed in the world marketplace. This would involve:
- Retrospective review of patient records.
- Post-market surveillance data.
- Compilation of reports from various human and animal studies (as stated: "Various human and animal reports are included in this submission for review").
This "ground truth" is therefore derived from a very large, diverse, and likely retrospective observational dataset of real-world clinical experience.
§ 870.3450 Vascular graft prosthesis.
(a)
Identification. A vascular graft prosthesis is an implanted device intended to repair, replace, or bypass sections of native or artificial vessels, excluding coronary or cerebral vasculature, and to provide vascular access. It is commonly constructed of materials such as polyethylene terephthalate and polytetrafluoroethylene, and it may be coated with a biological coating, such as albumin or collagen, or a synthetic coating, such as silicone. The graft structure itself is not made of materials of animal origin, including human umbilical cords.(b)
Classification. Class II (special controls). The special control for this device is the FDA guidance document entitled “Guidance Document for Vascular Prostheses 510(k) Submissions.”