(30 days)
The Niobe System is intended to navigate compatible magnetic devices through tissue to designated target sites in the right and left heart and coronary vascular and peripheral vasculature by orienting the device tip in a desired direction.
The Cardiodrive Catheter Advancement System (CAS) is intended to automatically advance and retract compatible magnetic electrophysiology (EP) mapping and ablation catheters inside the patient's heart when used in conjunction with a Stereotaxis MNS.
The Cardiodrive system is not intended to advance the EP mapping and ablation catheters through the coronary vasculature or the coronary sinus.
The Cardiodrive system is not intended to advance or retract non-compatible catheters and/or other non-compatible devices into the neurovasculature.
The Stereotaxis Niobe Magnetic Navigation System (MNS) with Navigant Workstation (NWS) and Cardiodrive (a.k.a. the Niobe System) is an interventional workstation for the intravascular navigation of appropriately equipped. magnetically adapted, devices (e.g., catheters or guidewires) through tissue to designated target sites. The Niobe System uses computer-controlled permanent magnets for orientating the tip of a magnetic device and employs magnetic fields only to orient or steer the tip of a magnetic device and remotely advance and retract only compatible magnetic electrophysiology (EP) mapping and ablation catheters inside the patient's heart. The Niobe System incorporates software that determines the direction the magnetic field should be applied based on physician interaction with the user interface devices.
This FDA 510(k) clearance letter for the Stereotaxis Niobe Magnetic Navigation System (MNS) with Navigant Workstation (NWS) and Cardiodrive (K192775) primarily references existing data from prior submissions and does not detail a new standalone clinical study. The submission relates to software modifications to an already cleared device, thus "special controls" testing and leveraging existing clinical data were used to demonstrate continued safety and effectiveness.
Here’s a breakdown of the acceptance criteria and the study information as presented in the document:
1. Table of Acceptance Criteria and Reported Device Performance
The document frames its "acceptance criteria" through how the device addresses a set of "Special Controls" established by the FDA for this class of device. The response to each control serves as the demonstration of meeting the criteria.
| Special Control (Acceptance Criteria) | How Special Control Has Been Met (Reported Device Performance) |
|---|---|
| 1) Non-clinical mechanical performance testing must demonstrate that the device performs as intended under anticipated conditions of use. Includes: | Magnetic field performance testing: Uses a THM-7025 Hall Effect tesla meter to measure applied field strength and accuracy in cardinal directions (at 0.08T and 0.1T - worst-case). |
| Manual Control Performance Testing (leveraged from predicate): Deflection testing, accuracy with target phantom, anatomical position testing with plastic heart model. Results provide mechanical performance for reference device. | |
| Remote Control Performance Testing (proposed device): Demonstrates equivalent mechanical performance between subject and reference device. | |
| Evaluation of accuracy/function of safety features: Testing of four primary safety controls related to physical motion (magnet positioners, cover movement, continuous catheter advancement, e-stops). All passed. | |
| Simulated-use testing: Four non-GLP animal validation studies performed using iterations of software after the reference device was cleared, testing features like sheath visualization, zone mapping, Auto NaviLine, single step NaviLine, targeting, point and line ablation, and integration of Acutus AcQMap system. | |
| 2) Non-clinical electrical testing must include validation of electromagnetic compatibility (EMC), electrical safety, thermal safety, and electrical system performance. | EMC and Electrical safety testing: Conformance with IEC 60601 performed by TuV for the reference device and the proposed device. All tests passed. |
| Electrical safety between device/ablation catheter system and other electrical equipment: Tested for compatibility with specific X-ray, ablation generators, mapping systems. Electrical isolation and emissions testing performed by TuV. All tests passed. | |
| 3) In vivo testing must demonstrate that the device performs as intended under anticipated conditions of use, including an assessment of the system impact on the functionality and performance of compatible catheters, and documentation of the adverse event profile associated with clinical use. Includes: | i. Manipulation and Positioning: The VERSATILE Study (K141530) and in vivo animal testing (K071029 for Cardiodrive) demonstrated ability to manipulate compatible catheters to pre-specified cardiac locations. |
| ii. Safety: Clinical data from four Stereotaxis-sponsored studies (ATTRAC, ATTRAC II, HEART, VERSATILE) totaling 511 patients reviewed. Overall 7-day major complication rate was 20/511 (3.9%). Specific adverse events reported (cardiac tamponade, thrombi, groin complication, etc.). | |
| iii. Efficacy: Data from the same four studies (ATTRAC, ATTRAC II, HEART, VERSATILE) reviewed. Acute success rates: 473/498 (95.0%). 90-day success rates: 278/288 (96.5%). | |
| iv. User assessment of device remote controls and safety features: Performance impressions documented on physician feedback forms during evaluations for Navistar RMT, Celsius RMT, and Helios II. Documentation included in reports. | |
| 4) Post-market surveillance (PMS) must be conducted and completed in accordance with FDA agreed upon PMS protocol. | Not warranted due to extensive clinical data. Safety and efficacy monitored through literature and PMS program. Major adverse event rate in submitted studies: 3.9%. Major complication rate in literature (>8,000 patients): 0.72% (vs. 2.1% manual). Acute and long-term success rates similar to manual. |
| 5) A training program must be included with sufficient educational elements for safe use. | Company representatives train physicians and staff. Niobe ES User's Manual provides detailed operating instructions. Information reviewed during simulation and phantom training. |
| 6) Performance data must demonstrate sterility of the sterile disposable components of the system. | Niobe System is not sterile and has no sterile disposable components. Cardiodrive includes a single-use disposable (QuikCAS) which underwent sterilization testing and passed. |
| 7) Performance data must support shelf life by demonstrating continued sterility, package integrity, and device functionality over the requested shelf life. | Niobe System is not sterile, so shelf life for sterility is not applicable. QuikCAS disposable underwent shelf-life/packaging and sterilization testing, passing all with a validated 3-year shelf life. |
| 8) Labeling must include appropriate instructions, warnings, cautions, limitations, and information. | Niobe ES User's Manual includes: Compatible Catheters, Indications for Use, Warnings, Safety Controls. Instructions for assembly (catheter-CAS interface), modes/states, controls/inputs/outputs, safety features. Cleaning instructions for non-reusable magnet pods included. Detailed summaries of mechanical compatibility testing (compatible catheters listed with pass/fail results) and in vivo testing (compatible catheters listed, adverse events, study outcomes, fluoroscopy times). |
2. Sample Sizes Used for the Test Set and Data Provenance
The document does not describe a novel "test set" in the context of typical AI/ML validation studies (i.e., a dedicated, novel set of cases exclusively for the purpose of algorithm validation). Instead, it relies heavily on retrospective clinical data from previously submitted studies and non-clinical engineering tests to demonstrate substantial equivalence for software modifications.
- Clinical Data (leveraged from prior submissions):
- Total Patients: 511 patients (across 4 studies: ATTRAC, ATTRAC II, HEART Study, VERSATILE)
- Attrition Data within Studies:
- ATTRAC: 182 enrolled patients, 175/182 for acute success, 145/147 for 90-day success.
- ATTRAC II: 80 enrolled patients, 71/75 for acute success, 51/54 for 90-day success.
- HEART Study: 129 enrolled patients, 108/121 for acute success, 82/87 for 90-day success.
- VERSATILE: 120 enrolled patients, 119/120 for acute success, "Not reported" for 90-day success.
- Data Provenance: The studies were Stereotaxis-sponsored clinical trials, previously submitted to the FDA for other clearances (P050029, K071029, K140804). The country of origin for these studies is not specified in this document. These are prospective studies given the "enrolled patients" context and "7-day major complication rate".
- Non-Clinical Data (specific to this submission):
- Software Verification and Validation: This involved internal testing by Stereotaxis under design controls. No specific "sample size" of software test cases is provided but it implies thorough testing.
- Animal Studies: Four non-GLP animal validation studies were conducted. The number of animals is not specified, but these are prospective studies to validate specific software features and integration.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of those Experts
Not applicable in the traditional sense of image-based AI ground truth. The "ground truth" for the clinical efficacy and safety data primarily comes from the patient outcomes and procedural data recorded during the clinical trials themselves, which would be managed by the clinical investigators (physicians) and study staff.
For user assessment of device remote controls and safety features, it mentions "physician feedback forms." This implies physicians were the "experts," but the number and their specific qualifications are not detailed.
4. Adjudication Method for the Test Set
For the clinical studies, adverse events were generally reported and reviewed, and in the VERSATILE Study, it explicitly states that the "DSM adjudicated these events to be possibly and probably related to the procedure, respectively." DSM typically refers to a Data Safety Monitoring Board, which is an independent committee of experts (e.g., clinicians, biostatisticians) that monitors patient safety and treatment efficacy data during clinical trials. This suggests an adjudication method, at least for some adverse events.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and Effect Size of AI vs. Without AI Assistance
No MRMC study is mentioned. This submission is for a device that assists with navigation, not for an AI that interprets images or diagnoses conditions in a way that would typically involve multiple readers assessing cases. The device itself is the "AI" (automated navigation based on software). Comparative effectiveness is primarily drawn from historical controls or comparisons to manual procedures mentioned in the PMS section (e.g., complication rates vs. manual rates).
6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Was Done
The device is a "Steerable Cardiac Ablation Catheter Remote Control System." Its core function is to automate or assist in catheter navigation, inherently requiring a human operator (physician) to interact with the system. Therefore, a standalone (algorithm only) performance study without human-in-the-loop is not directly relevant or performed for the primary function of controlling the catheter. However, the mechanical and electrical performance tests (Special Controls 1 & 2) represent isolated system performance without a human in the loop, validating individual components of the system.
7. The Type of Ground Truth Used
- Clinical Studies: Patient outcomes (acute success, 90-day success, complication rates) serve as the ground truth for safety and efficacy. This is primarily outcomes data, determined by clinical follow-up and assessments from physicians.
- Non-Clinical Studies: Ground truth for mechanical and electrical performance is established via measurement against engineering specifications and validated standards (e.g., THM-7025 Hall Effect tesla meter, IEC 60601 conformance).
- Animal Studies: The success of specific software features in animal models (e.g., successful targeting, ablation) serves as the ground truth. This is a form of experimental outcome data.
8. The Sample Size for the Training Set
This document does not describe the Niobe System as an AI/ML device in the modern sense (e.g., a deep learning model requiring a large training dataset of images or other raw data). The "software modifications" refer to updates to the control system. Therefore, there's no mention of a traditional "training set" size for an AI algorithm. The development of software would involve internal testing and validation, but not "training data" in the AI/ML context.
9. How the Ground Truth for the Training Set Was Established
As no specific AI/ML training set is described, this question is not applicable. The traditional software development and verification/validation processes would have established "ground truth" through requirements documentation, test specifications, and expected outputs.
§ 870.5700 Steerable cardiac ablation catheter remote control system.
(a)
Identification. A steerable cardiac ablation catheter remote control system is a prescription device that is external to the body and interacts with the manual handle of a steerable cardiac ablation catheter to remotely control the advancement, retraction, rotation, and deflection of a compatible, steerable ablation catheter used for the treatment of cardiac arrhythmias in the right side of the heart. The device allows reversion to manual control of the steerable cardiac ablation catheter without withdrawal of the catheter and interruption of the procedure.(b)
Classification. Class II (special controls). The special controls for this device are:(1) Non-clinical mechanical performance testing must demonstrate that the device performs as intended under anticipated conditions of use. The following performance testing must be performed:
(i) Mechanical performance of the system (without catheter connected);
(ii) Mechanical performance of the system with compatible catheters connected to verify that the system does not impact catheter function or performance. Assessments must include the following:
(A) Side-by-side remote control and manual comparisons of catheter manipulation (including all ranges of motion of catheter deflection and tip curl) for all compatible catheters; must include testing for worst-case conditions, and
(B) Evaluation of the accuracy and function of all device control safety features; and
(iii) Simulated-use testing in a bench anatomic model or animal model.
(2) Non-clinical electrical testing must include validation of electromagnetic compatibility (EMC), electrical safety, thermal safety, and electrical system performance. The following performance testing must be performed:
(i) Electrical performance of the system with compatible catheters connected to verify that the system does not impact catheter function or performance. Assessments must include the following:
(A) Side-by-side remote control and manual comparisons of catheter manipulation (including all ranges of motion of catheter deflection and tip curl) for all compatible catheters; must include testing for worst-case conditions, and
(B) Evaluation of the accuracy and function of all device control safety features; and
(ii) Electrical safety between the device and ablation catheter system and with other electrical equipment expected in the catheter lab or operating room.
(3) In vivo testing must demonstrate that the device performs as intended under anticipated conditions of use, including an assessment of the system impact on the functionality and performance of compatible catheters, and documentation of the adverse event profile associated with clinical use. Evidence must be submitted to address the following:
(i) Manipulation and Positioning: Ability to manipulate compatible catheters to pre-specified cardiac locations and confirm proper anatomic placement and tissue contact, in accordance with the system indications for use and the compatible catheter indications for use;
(ii) Safety: Assess device-related complication rate and major procedural complication rate (regardless of device relatedness) in comparison to literature and/or a manual comparison group for compatible ablation catheters to support the indications for use;
(iii) Efficacy: Assess ablation success in comparison to literature and/or a manual comparison group for compatible ablation catheters to support the indications for use; and
(iv) User assessment of device remote controls and safety features.
(4) Post-market surveillance (PMS) must be conducted and completed in accordance with FDA agreed upon PMS protocol.
(5) A training program must be included with sufficient educational elements that, upon completion of the training program, the clinician and supporting staff can:
(i) Identify the safe environments for device use,
(ii) Use all safety features of device, and
(iii) Operate the device in simulated or actual use environments representative of indicated environments and use for the indication of compatible catheters.
(6) Performance data must demonstrate the sterility of the sterile disposable components of the system.
(7) Performance data must support shelf life by demonstrating continued sterility of the device (of the sterile disposable components), package integrity, and device functionality over the requested shelf life.
(8) Labeling must include the following:
(i) Appropriate instructions, warnings, cautions, limitations, and information related to the intended patient population, compatible ablation catheters, and the device safeguards for the safe use of the device;
(ii) Specific instructions and the clinical training needed for the safe use of the device, which includes:
(A) Instructions on assembling the device in all available configurations, including installation and removal of compatible catheters;
(B) Instructions and explanation of all controls, inputs, and outputs;
(C) Instructions on all available modes or states of the device;
(D) Instructions on all safety features of the device; and
(E) Validated methods and instructions for reprocessing/disinfecting any reusable components;
(iii) A detailed summary of the mechanical compatibility testing including:
(A) A table with a complete list of compatible catheters tested (manufacturer trade name and model number), and
(B) A table with detailed test results, including type of test, acceptance criteria, and test results (
i.e., pass for meeting acceptance criteria);(iv) A detailed summary of the in vivo testing including:
(A) A table with a complete list of compatible catheters used during testing (manufacturer trade name and model number);
(B) Adverse events encountered pertinent to use of the device under use conditions;
(C) A detailed summary of the device- and procedure-related complications; and
(D) A summary of study outcomes and endpoints. Information pertinent to the fluoroscopy times/exposure for the procedure, patient, and operator fluoroscopic exposure;
(v) Other labeling items:
(A) A detailed summary of pertinent non-clinical testing information: EMC, mechanical, electrical, and sterilization of device and components;
(B) A detailed summary of the device technical parameters; and
(C) An expiration date/shelf life and storage conditions for the sterile accessories; and
(vi) When available, and according to the timeframe included in the PMS protocol agreed upon with FDA, provide a detailed summary of the PMS data including:
(A) Updates to the labeling to accurately reflect outcomes or necessary modifications based upon data collected during the PMS experience, and
(B) Inclusion of results and adverse events associated with utilization of the device during the PMS.