(188 days)
SYNOX leads are designed for use with implantable pulse generators which require pacing leads with a bipolar 3.2 mm IS-1 connector configuration; they may be used with single or dual chamber pacing systems. The leads are designed for use in patients for whom single or dual chamber pulse generator therapy is medically indicated. This indication follows that 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).
SYNOX passive-fixation endocardial leads are safe and effective bipolar leads designed for use with implantable pulse generators which require bipolar 3.2 mm IS-1 compatible pacing leads. SYNOX bipolar passive-fixation endocardial leads are available in straight and "J"-shaped conformations, for pacing and sensing in the ventricle and atrium, respectively. The designation SX xx-JBP refers to SYNOX "J"-shaped leads, which are available in lengths of 45 and 53 cm; SX xx-BP refers to SYNOX straight leads, which are available in lengths of 53 or 60 cm.
The SX xx-JBP model has a permanent bend proximal to both lead electrodes, approximately 40 mm from the lead tip, resulting in the distal portion of the lead body having what is commonly referred to as a "U" or "J" shape. This lead shape facilitates placement in the right atrial appendage.
These leads provide long-term safe and effective pacing through overall quality of design, manufacture and material biocompatibility. All SYNOX patient contact materials are commonly used in market-released leads. Acute and chronic biocompatibility tests have been performed, as well as long-term implantation studies. In addition, corrosion studies have been completed to address both long-term toxicity and durability of the surface iridium treatment. The testing conducted for biocompatibility as well as extensive clinical experience confirms that iridium is safe for use as an implantable material, and analyses supporting this view have been published within technical journals. Long-term corrosion testing results substantiate that iridium is a non-toxic and durable material for use in implantable devices.
Here's an analysis of the provided text regarding the acceptance criteria and study for the SYNOX pacing leads:
1. Acceptance Criteria and Reported Device Performance
The document does not explicitly present a formal "table of acceptance criteria" with numerical targets and corresponding performance metrics for all aspects of the device. However, it implicitly defines success through the clinical study's objectives and reported outcomes. Based on the "Summary of Studies" and "Clinical Studies" sections, we can infer the following:
| Acceptance Criteria (Inferred) | Reported Device Performance |
|---|---|
| Safety: | |
| No unanticipated adverse device effects. | "There were no reports of any unanticipated adverse device effects occurring during the clinical investigation." |
| No safety issues related to chronic use. | "There have been no reports of safety issues related to the chronic use of the pacing lead." |
| All anticipated adverse events resolved. | "All of the anticipated adverse events reported, except for the one lead explant described above, were resolved by the investigator through reprogramming, drug therapy, or lead repositioning." |
| Combined adverse event rates not statistically different from control. | "The combined rates of anticipated and unanticipated adverse events for the SYNOX leads are not statistically different from the rates for the control leads." |
| Effectiveness (Pacing/Sensing Performance): | |
| Mean pacing impedance as expected (higher than control due to smaller tip area). | "As expected, due to the decreased lead tip area (1.3 mm2 for SYNOX vs 3.5 mm² for POLYROX) the mean measured atrial and ventricular lead pacing impedance for SYNOX leads was more than 150 ohms over the mean measured atrial and ventricular lead pacing impedance for the control leads at all of the follow-up intervals." |
| Mean capture and sensing thresholds equal to or better than control. | "The mean capture and sensing thresholds of the SYNOX leads were equal to or better than the control leads for all of the follow-up intervals." |
| Atrial sensing and pacing performance comparable to control. | "The atrial sensing and pacing performance of the SYNOX leads were comparable to the control leads." |
| Ventricular sensing and pacing performance comparable to control. | "The ventricular sensing and pacing performance of the SYNOX leads were comparable to the control leads." |
| Biocompatibility/Biostability (Non-clinical): | |
| No measurable corrosion attack of electrodes. | "Electrochemical and corrosion resistance analysis results from the in vivo Hungarian dog investigation indicate that fractal iridium structured electrode surfaces are stable against any measurable corrosion attack when electrically loaded and chronically implanted." |
| No observable foreign material in tissue. | "Results from a histological evaluation of the tissue in the vicinity of the electrode tips showed no observable iridium, titanium or platinum in either the three-month implant samples or the six-month samples." |
| Overall excellent long-term electrophysiological properties. | "Based upon these findings and other performance data collected, the investigators concluded that the endocardial leads tested have excellent long term electrophysiological properties." |
| Mechanical, electrical, and environmental tests met specifications. | "Qualification testing was performed... In all cases, test specifications were met." |
| Superior or equivalent fatigue resistance. | "SYNOX conductor coils exhibited superior fatigue resistance as compared to the market-released control lead: therefore, fatigue resistance of the SYNOX lead is expected to be at least as good as the control lead." |
| Less lead tip rigidity than other marketed leads. | "Test results demonstrate that SYNOX lead tip rigidity is less than that of other marketed endocardial leads." |
2. Sample Size for the Test Set and Data Provenance
- Clinical Study (Test Set): The document doesn't explicitly state the exact number of patients or leads in the ongoing prospective clinical study (IDE G960236). It mentions "the four patient deaths during the study" suggesting at least four patients, but the overall sample size for evaluating lead performance is not provided.
- Data Provenance:
- Clinical Study (IDE G960236): Prospective, conducted by BIOTRONIK GmbH & Co. The country of origin for this specific IDE study is not explicitly stated, but it's an investigational device exemption, typically implying a study conducted under FDA oversight, often in the US or with US sites.
- Hungarian Dog Study: Prospective, in vivo, conducted in Hungary.
- French SYNOX Lead Study: Prospective, conducted in France.
- Nonclinical Studies: In vitro and mechanical/electrical testing, typically performed in a laboratory setting.
3. Number of Experts used to Establish the Ground Truth for the Test Set and Qualifications of those Experts
The document does not specify the number or qualifications of experts establishing ground truth for the clinical study directly. However, it indicates:
- The clinical study was "initiated... under IDE G960236," implying oversight by investigators (likely electrophysiologists or cardiologists) who would establish the "ground truth" of lead performance and adverse events based on their clinical assessments.
- "All of the anticipated adverse events reported... were resolved by the investigator," indicating their role in assessment and management.
For the Hungarian dog study, "investigators" concluded on "excellent long term electrophysiological properties" and conducted histological evaluation. These would likely be veterinary researchers, pathologists, and electrophysiologists.
4. Adjudication Method for the Test Set
The document does not describe a formal adjudication method (e.g., 2+1, 3+1) for the clinical study's endpoints or adverse events. Clinical trial data is typically reviewed and documented by the principal investigators at each site, and adverse events are reported according to regulatory requirements. The phrase "resolved by the investigator" suggests the investigator was the primary point of decision for adverse event management. Without further detail, it's assumed that the standard clinical trial practices of the time (late 1990s) were followed, but no specific adjudication committee or process is detailed.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No. An MRMC comparative effectiveness study is designed to evaluate changes in human reader performance (e.g., diagnostic accuracy) when assisted by AI versus without AI. This device is a pacing lead, not an interpretive diagnostic tool that involves human "readers" in the context of interpretation with AI assistance.
6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study
Yes, in a sense, the nonclinical and in-vivo animal studies represent "standalone" performance evaluations of the device itself (the pacing lead) without direct human interpretive intervention (as would be the case for AI). The clinical study, while involving human patients, evaluates the device's intrinsic function and safety. The entire submission is focused on the device's standalone performance.
7. Type of Ground Truth Used
- Clinical Study: Clinical outcomes (adverse events, pacing thresholds, sensing values, impedance, lead explantation reasons) observed and documented by clinical investigators and measured by standard pacing system analyzers. This represents clinical performance data and patient outcomes.
- Hungarian Dog Study: Direct physiological measurements (electrical performance), histology for biocompatibility and foreign material assessment, and electrochemical analysis for corrosion resistance.
- Nonclinical Studies: Engineering test specifications and direct physical/electrical measurements (e.g., fatigue resistance, rigidity, electrical parameters, sterility).
8. Sample Size for the Training Set
This document describes pre-market approval studies for a physical medical device (pacing lead), not a machine learning model. Therefore, there is no "training set" in the context of artificial intelligence or machine learning. The device's design is based on accumulated engineering knowledge, previous device designs (predicate device POLYROX), and material science, not an iterative training process on a dataset.
9. How the Ground Truth for the Training Set was Established
As there is no AI/ML training set, this question is not applicable to the submitted document.
§ 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.