(120 days)
The BIOTRONIK RETROX RX 53/60-BP and RETROX RX 45/53-JBP transvenous, active fixation endocardial leads are indicated for permanent pacing and sensing. Active fixation pacing leads with a bipolar (BP) IS-1 connector configuration are designed for use in conjunction with implantable pulse generators. The leads may be used with singleor dual-chamber pacing systems.
RETROX RX-BP and RX-JBP leads differ in the shape of the distal portion of the lead. The RX-BP models are intended for placement in the ventricle or atrium and have straight distal ends. The RX-JBP models have a pre-formed J-shaped distal end to facilitate lead placement in the right atrial appendage.
The indications for use of a RETROX lead in combination with a connected cardiac pacemaker follow those recommended in the Class I definition of the ACC/AHA Task Force Report, entitled "Guidelines for Implantation of Cardiac Pacemakers and Antiarrhythmic Devices" (JACC, Vol. 18, No. 1, July 1991:1-13.)
The RETROX endocardial lead is a safe and effective biopolar sense/pace lead used with implantable cardiac pacemakers when an active-fixation endocardial lead is preferred. The lead body insulation is NuSil MED-4750 silicone rubber tubing, with a conductor of quadrafilar MP35N wire.
These leads provide long-term safe and effective pacing through overall quality of design, manufacture and the surface structure of the active-fixation electrode tip. This tip is a single helically-wound fixation wire ("fixation screw") composed of 70% platinum and 30% iridium.
Here's an analysis of the provided text regarding the RETROX endocardial lead, structured according to your request.
1. Table of Acceptance Criteria and Reported Device Performance
The provided text does not explicitly state quantitative acceptance criteria for the clinical performance of the RETROX lead in the format you might expect for a typical AI/ML study (e.g., sensitivity, specificity, accuracy thresholds). The "acceptance criteria" are implied by the successful completion of various non-clinical tests and the absence of unanticipated adverse events in the limited clinical study.
| Acceptance Criteria Category | Specific Criteria (Implicit) | Reported Device Performance |
|---|---|---|
| Biocompatibility | - Patient-contact materials are commonly used in market-released leads. |
- Iridium is safe for use as an implantable material.
- Long-term corrosion testing substantiates iridium as non-toxic and durable. | - Patient-contact materials are commonly used.
- Extensive clinical experience and published technical journals confirm iridium safety.
- Long-term corrosion testing results substantiate iridium's non-toxicity and durability. |
| Device Integrity & Function | - IS-1 BP connector testing specifications met. - Si tube abrasion testing specifications met.
- Lead tip and ring testing specifications met.
- Complete lead mechanical, electrical and environmental testing specifications met.
- Silicone adhesive testing specifications met.
- Suture sleeve testing specifications met.
- Sterile package testing specifications met. | - "All test results were within specifications."
- "In all cases, test specifications were met." (for all nonclinical tests listed) |
| Clinical Safety | - No unanticipated adverse device effects. - Similar risk profile to other market-released active fixation retractable endocardial leads.
- Patient death not related to the pacing system. | - "There have been no unanticipated adverse device effects experienced with the RETROX pacing leads as defined in 21 CFR 812.3(s)."
- "Three anticipated adverse events have been recorded associated with the 14 study leads implanted to date; four anticipated adverse events have been recorded associated with the 17 control leads implanted to date." (Note: The specific events are not detailed in the summary, but their anticipation implies they are known complications for this device type).
- "The patient had been randomized to control leads... This death was evaluated by the investigator and determined to be unrelated to the pacing system." |
| Clinical Effectiveness | - The lead provides "long-term safe and effective pacing" (general claim, not a specific criterion for the limited clinical study). - "Used with implantable cardiac pacemakers when an active-fixation endocardial lead is preferred." (general claim, not a specific criterion for the limited clinical study).
- Absence of specific complications like loss of pacing/sensing, or significant increase/decrease in threshold due to the device itself (though generic complications are acknowledged). | The clinical studies section focuses primarily on safety reporting. While the device is marketed as "safe and effective," direct quantitative effectiveness metrics from the limited clinical study (e.g., pacing capture thresholds, sensing amplitudes over time for the RETROX vs. control leads) are not provided in this summary. The summary only mentions "anticipated adverse events" for both study and control leads. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size (Clinical):
- RETROX Leads: 14 leads
- Control Leads (Oscor): 17 leads
- Total Patients: 19 patients (implies some patients received both study and control, or multiple leads of one type, but the breakdown isn't explicitly given beyond "14 RETROX leads and 17 control (Oscor) leads were implanted")
- Data Provenance: The study is described as a "Non-U.S. and limited U.S. clinical experience" and an "Interim Clinical Investigation Summary." Given the document's context (510(k) submission to FDA), it's highly likely to be prospective clinical trial data, but the exact countries are not specified beyond "non-U.S. and limited U.S."
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
The concept of "ground truth" and "experts" as typically understood in AI/ML model validation (e.g., for image interpretation) is not applicable here. This document describes a medical device's pre-market approval, where the "ground truth" for safety and performance comes from:
- Physical and Electrical Measurements: For the nonclinical tests.
- Clinical Observation and Medical Diagnostics: For the clinical study, where adverse events are assessed by "the investigator" (a physician responsible for the clinical trial).
- Pathology/Outcomes Data: If relevant for specific events (e.g., patient death unrelated to device, which would be determined by medical investigation, potentially including pathology).
The document mentions a patient death "was evaluated by the investigator," who would be a qualified medical professional (e.g., cardiologist). No specific number or qualifications of a panel of experts for establishing ground truth are mentioned as would be common in an AI evaluation.
4. Adjudication Method for the Test Set
Again, the concept of an adjudication method (like 2+1, 3+1 for expert review) is not applicable to this type of medical device study. Adverse event reporting and assessment typically follow a different process:
- Events are reported by clinicians to the sponsor.
- The sponsor and/or an independent clinical events committee (CEC) (often composed of medical experts) reviews the event for causality and severity.
- The "investigator" is explicitly mentioned as evaluating the patient death for relatedness.
There is no mention of a formal adjudication process using multiple independent readers for subjective assessments.
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 comparative effectiveness study involving human readers and AI assistance was not done. This is a pre-market approval document for an implantable cardiac lead, not an AI diagnostic or assistance tool. The clinical study compares the RETROX lead to a control (Oscor) lead, both being physical medical devices.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
No, this refers to a physical medical device (an endocardial lead), not a standalone algorithm. Therefore, this question is not applicable.
7. The Type of Ground Truth Used
The ground truth for this device's performance assessment is a combination of:
- Engineering/Physical Measurements: Specifications met for IS-1 BP connector, Si tube abrasion, lead tip and ring, mechanical, electrical, environmental, adhesive, suture sleeve, and sterile package testing.
- Biocompatibility Testing: Corrosion studies, review of existing data on materials (iridium, silicone).
- Clinical Observation/Outcomes Data: Observed adverse events (anticipated vs. unanticipated), patient follow-up, and investigator's assessment of event relatedness (e.g., patient death being unrelated).
8. The Sample Size for the Training Set
This product is a physical medical device, not an AI/ML model. Therefore, the concept of a "training set" in the context of machine learning is not applicable. The lead's design and manufacturing are based on established engineering principles, material science, and prior clinical experience with similar devices, rather than a data-driven training process.
9. How the Ground Truth for the Training Set was Established
As the "training set" concept is not applicable for this device, neither is the establishment of its ground truth. The design and validation relied on:
- Engineering principles and specifications.
- Material science data and prior use history.
- Pre-clinical testing results.
- Existing clinical experience with similar predicate devices.
§ 870.3680 Cardiovascular permanent or temporary pacemaker electrode.
(a)
Temporary pacemaker electrode —(1)Identification. A temporary pacemaker electrode is a device consisting of flexible insulated electrical conductors with one end connected to anexternal pacemaker pulse generator and the other end applied to the heart. The device is used to transmit a pacing electrical stimulus from the pulse generator to the heart and/or to transmit the electrical signal of the heart to the pulse generator.(2)
Classification. Class II (performance standards).(b)
Permanent pacemaker electrode —(1)Identification. A permanent pacemaker electrode is a device consisting of flexible insulated electrical conductors with one end connected to an implantable pacemaker pulse generator and the other end applied to the heart. The device is used to transmit a pacing electrical stimulus from the pulse generator to the heart and/or to transmit the electrical signal of the heart to the pulse generator.(2)
Classification. Class III (premarket approval).(c)
Date PMA or notice of completion of PDP is required. A PMA or notice of completion of a PDP is required to be filed with the Food and Drug Administration on or before October 4, 2012, for any permanent pacemaker electrode device that was in commercial distribution before May 28, 1976, or that has, on or before October 4, 2012, been found to be substantially equivalent to any permanent pacemaker electrode device that was in commercial distribution before May 28, 1976. Any other pacemaker repair or replacement material device shall have an approved PMA or declared completed PDP in effect before being placed in commercial distribution.