(155 days)
The HeRO® Graft is intended use in maintaining long term vascular access for chronic hemodialysis patients who have exhausted venous access sites suitable for fistulas or grafts.
The HeRO® Graft is indicated for end stage renal disease patients on hemodialysis who have exhausted all other access options. These catheter-dependent patients are readily identified using the KDOQI guidelines¹ as patients who:
• Have become catheter-dependent or who are approaching catheter dependency (i.e., have exhausted all other access options, such as arteriovenous fistulas and grafts).
• Are not candidates for upper extremity fistulas or grafts due to poor venous outflow as determined by a history of previous access failures or venography.
• Are failing fistulas or grafts due to poor venous outflow as determined by access failure or venography (e.g. fistula/graft salvage).
• Have poor remaining venous access sites for creation of a fistula or graft as determined by ultrasound or venography.
• Have a compromised central venous system or central venous stenosis (CVS) as determined by a history of previous access failures, symptomatic CVS (i.e., via arm, neck, or face swelling) or venography.
• Are receiving inadequate dialysis clearance (i.e., low Kt/V) via catheters. KDOQI guidelines recommend a minimum Kt/V of 1.4.
The HeRO Graft is a non-autogenous (i.e., synthetic) vascular graft prosthesis which provides arterial venous access with continuous outflow into the central venous system. The HeRO Graft is composed of the following components: (1) Venous Outflow Component (VOC), (2) Arterial Graft Component (AGC) or HeRO Adapter with Support Seal (used in conjunction with commercial vascular grafts), and (3) Accessory Component Kit (ACK). The VOC consists of a radiopaque silicone base tube, a nitinol braid (imparts kink and crush resistance), a distal radiopaque marker band, and an outer silicone elastomer encapsulation layer. During surgery, the VOC is cut to length for the patient anatomy and then advanced over the barbs of the AGC Connector or HeRO Adapter. The AGC is a conventional ePTFE vascular graft with a guideline and beading near the custom titanium alloy connector to provide kink resistance. As an alternative to the AGC, the titanium alloy HeRO Adapter with Support Seal allow the clinician to choose one of the commercially available 6mm ID vascular grafts qualified for use with the HeRO Graft. The ACK (a convenience kit) contains instruments that aid in the implantation of the HeRO Graft including, introducers, dilators, delivery stylet, hemostasis valve with stopcock, disposable clamp, and hemostasis plug. The HeRO Graft is a fully subcutaneous surgical implant single-use device provided sterile via ethylene oxide for long-term (>30 day) use.
This document describes the premarket notification (510(k)) for the Merit HeRO Graft, a vascular graft prosthesis. The provided text details the device description, indications for use, and a comparison to a predicate device, as well as a list of performance and design validation tests, and an animal study. However, it does not contain the specific acceptance criteria and detailed device performance results in a table format that would directly fulfill all aspects of your request. It rather lists the types of tests conducted and states that the device met the requirements.
Based on the provided text, I can infer and organize the available information to best answer your request, highlighting where direct numerical acceptance criteria or performance values are not explicitly stated in this FDA submission summary.
Here's a breakdown of the information that can be extracted and inferred, structured to align with your questions:
1. A table of acceptance criteria and the reported device performance
The document states that a "battery of tests was performed based upon the risk analysis and the requirements of the following internationally recognized standards and guidance documents pertaining to the device performance, as well as biocompatibility, sterilization, and labeling standards and guidance. Conformity to these standards demonstrates that the proposed HeRO Graft meets the acceptance criteria established by the standards as they apply to device safety and efficacy."
While specific numerical acceptance criteria and precise performance values are not given in a table, the document broadly describes the types of tests and the overall outcome.
| Test Category / Parameter | Acceptance Criteria (Inferred from text) | Reported Device Performance (Inferred from text) |
|---|---|---|
| Biocompatibility Testing | Conformity to ISO 10993 series and FDA guidance (e.g., Cytotoxicity, Sensitization, Irritation, Acute Systemic Toxicity, Pyrogenicity, Hemolysis, etc.) | Met the biocompatibility requirements for implant device with tissue and circulating blood contact for permanent (>30 days) duration. No adverse findings. |
| Performance Testing | Conformity to relevant standards (e.g., specific values for strength, porosity, permeability, leakage, etc. as per ISO 7198, ASTM F756) | Device successfully passed all listed performance tests (Dimension Verification, Longitudinal Tensile Strength, Pressurized Burst Strength, Kink Diameter, Microscopic Porosity, Water Entry Pressure, Integral Water Permeability, Clamp Leakage, Suture Retention Strength, Beading Peel Strength, Strength after Repeated Puncture). |
| Design Validation Testing | Conformity to relevant standards for functionality and handling (e.g., ability to accept guidelines, resistance to kinks, ease of handling/cutting). | Device successfully passed all listed design validation tests (Guideline Acceptability, Kink Resistance, Handling, Cutting, Syringe Adapter Compatibility, Suturability). |
| Animal Study (Patency, Stenosis, Thrombogenicity) | Equal to or better performance than the control article in terms of patency, stenosis, thrombogenicity, and cell/tissue response. | Test articles demonstrated equal to or better patency, stenosis, thrombogenicity, cell and tissue response compared to control articles at 30, 90, and 180 days. |
| Animal Study (Adverse Events/Mortality) | No premature deaths or adverse clinical sequelae related to the test article or control article. | No premature deaths related to test/control articles. No adverse clinical sequelae or animal mortality related to the presence of the test article. |
| Overall Safety and Performance | Meets requirements for intended use, comparable to predicate in safety and performance. | The Merit test article was as safe and performed as well as the control article. Substantially equivalent to the predicate device. |
2. Sample sized used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Animal Study Test Set Sample Size: 18 sheep.
- Data Provenance: The document does not specify the country of origin of the animal study data or if the performance/design validation tests were conducted externally. The animal study was generally described as "chronic study" with set time points (30-day, 90-day, 180-day), indicating a prospective setup for that specific component. The other performance and design validation tests are typical of pre-market, laboratory-based testing.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
- The document describes a device (vascular graft), not an AI/diagnostic software. Therefore, the concept of "ground truth" established by human experts in the context of diagnostic interpretation (like radiologists) is not applicable here. The ground truth for device performance is established through physical and biological testing against established standards and controls (e.g., precise measurements, chemical analyses, histological assessments in the animal study).
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
- This concept applies to human interpretation of data, typically in diagnostic studies. As this is a medical device (vascular graft) and not a diagnostic AI, adjudication methods for expert interpretation are not relevant or described. Device performance testing relies on objective measurements and verified protocols.
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
- No, an MRMC study was not done. This type of study is specific to evaluating the clinical performance of diagnostic AI systems in conjunction with human readers. The Merit HeRO Graft is a physical implantable device, not an AI software.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- This question is also not applicable. The device is a physical vascular graft, not an algorithm. Performance tests are inherently "standalone" in the sense that they evaluate the device's physical and biological properties.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
- For Biocompatibility Testing: Ground truth is established by standardized laboratory assays and results against accepted biological safety limits (e.g., no cytotoxicity, no irritation, no genotoxicity).
- For Performance and Design Validation Testing: Ground truth is established by engineering specifications, physical measurements, and conformity to recognized international standards (e.g., ISO 7198, ASTM F756).
- For the Animal Study: Ground truth was established by direct observation, angiographic evaluation, and histopathologic evaluations (pathology) of the implanted grafts and non-target organs. Patency, stenosis, thrombogenicity, and cellular/tissue response were assessed and compared to control articles.
8. The sample size for the training set
- This question is for AI models. As this is a physical medical device, there is no "training set" in the AI sense. Device development involves design, prototyping, and testing, not machine learning model training.
9. How the ground truth for the training set was established
- Not applicable, as there is no AI training set.
§ 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.”