(162 days)
The DIASTAT Vascular Access Graft, intended for use as a vascular prosthesis in patients requiring vascular access, and which may be cannulated within one week of implantation
The DIASTAT Vascular Access Graft is essentially an expanded PTFE vascular graft with the addition of one or more externally applied cannulation segments comprised of expanded PTFE fibers and an expanded PTFE covering. The graft is provided with or without external reinforcement in the form of FEP rings which may be fixed or removable, and in either extensible or non-stretch configurations.
Here's an analysis of the provided text regarding the acceptance criteria and supporting study for the DIASTAT® VASCULAR ACCESS GRAFT:
1. Table of Acceptance Criteria and Reported Device Performance
Based on the provided text, the acceptance criteria are implicitly linked to the concept of "substantial equivalence" to predicate devices. The performance metrics reported focus on aspects where the DIASTAT graft demonstrates specific advantages or similar performance to these predicates.
| Acceptance Criteria (Implicit) | Reported Device Performance |
|---|---|
| Substantial equivalence in performance to predicate devices (e.g., Plasma TFE Vascular Graft, GORE-TEX Vascular Grafts) | Confirmed through characterizations, tests, and observations that the DIASTAT Vascular Access Graft is substantially equivalent to the Plasma TFE Vascular Graft for cannulation within one week of implantation. |
| Does not raise new issues of safety and effectiveness compared to predicate devices. | "DIASTAT Vascular Access Graft does not raise any new issues of safety and effectiveness." No new biocompatibility or blood-contact issues. |
| Reduced fluid leakage (compared to predicates or general expectations for vascular grafts). | Demonstrated in bench testing (using water, a liquid more likely to leak than heparinized blood). |
| Reduced times to hemostasis (compared to predicates or general expectations for vascular grafts). | Demonstrated in animal testing. |
| Reduced blood loss in vivo (compared to predicates or general expectations for vascular grafts). | Demonstrated in animal testing. |
| Reduced incidence of hematoma (compared to predicates or general expectations for vascular grafts). | Demonstrated in animal testing. |
| Mechanical low bleed feature. | Possesses a "specific mechanical low bleed feature which has been characterized in bench tested in vivo and observed in the clinical setting." |
| Appropriately addresses potential risks of early cannulation (e.g., infection, patency). | Risks addressed in proposed labeling changes emphasizing strict aseptic technique for early cannulations. |
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Sample Size: Not explicitly stated. The text mentions "bench testing," "animal testing," and being "observed in the clinical setting," but no specific sample sizes for these tests are provided.
- Data Provenance:
- Bench Testing: In-house (W.L. Gore & Associates Inc. laboratories).
- Animal Testing: In-house (W.L. Gore & Associates Inc. laboratories).
- Clinical Setting: Observations in a "clinical setting" are mentioned, but it's not described as a formal clinical trial with a defined population. It is stated that a "prospective randomized clinical study of early cannulation of the DIASTAT Vascular Access Graft was not performed." This suggests the clinical observations were likely retrospective or informal case observations rather than a structured prospective study.
- Country of Origin: Implied to be the USA, given the headquarters of W.L. Gore & Associates Inc.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
- This information is not provided. The document describes mechanical tests and animal studies, not human expert evaluations for establishing ground truth in the traditional sense of diagnostic accuracy studies.
4. Adjudication Method for the Test Set
- Not applicable/Not provided. The studies described are primarily performance and safety characteristic evaluations, not a diagnostic test being adjudicated by experts.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
- No, a MRMC comparative effectiveness study was not done. The document explicitly states: "A prospective randomized clinical study of early cannulation of the DIASTAT Vascular Access Graft was not performed." The comparison is based on substantial equivalence to predicate devices through mechanical and animal testing, and observations, rather than a clinical trial directly comparing human readers with and without AI assistance (which is what MRMC studies often evaluate when AI is involved).
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
- This question is not applicable as the device is a physical vascular graft, not an algorithm or AI system for diagnostic interpretation. The performance discussed is inherent to the physical device.
7. The Type of Ground Truth Used
- Bench Testing: Physical measurements and observations of fluid leakage using water.
- Animal Testing: Direct observation and measurement of physiological parameters (hemostasis time, blood loss, hematoma incidence) in animal models.
- Clinical Setting: "Observations" indicate real-world outcomes, likely without a formally established "ground truth" as would be defined in a clinical trial. The "ground truth" here is implied to be the direct observed in vivo performance and absence of unexpected adverse events.
8. The Sample Size for the Training Set
- Not applicable as this is a physical medical device, not a machine learning model requiring a training set.
9. How the Ground Truth for the Training Set Was Established
- Not applicable, as there is no training set for this type of device.
§ 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.”