(30 days)
The SENTINEL System is intended for use by patients who either have or are at risk of having cardiac disease and those that demonstrate intermittent symptoms indicative of cardiac disease and require cardiac monitoring on a continuing basis.
The device continuously records the ECG data and transfers the data to the Server. Upon detection by an ECG analysis algorithm at the Server the recorded cardiac activity is flagged for review by a medical professional. The data received from the SENTINEL device can be used by another cleared device for arrhythmia analysis, reporting and signal measurements. The SENTINEL System is not intended to sound any alarms.
The device does not deliver any therapy, administer any drugs, provide interpretative or diagnostic statements or provide for any life support.
The SENTINEL System is for prescription use only.
Cardiomedix ECG SENTINEL System is a self-use, 2-lead ECG continuous acquisition and transmission system. The SENTINEL device connects via Bluetooth to a proprietary mobile phone-based, dedicated ECG acquisition, storage, and transmission application. The phone application facilitates the self-use of the device by providing messages and alerts for specific parameters.
ECG SENTINEL System refers to the complete system with all component parts.
SENTINEL refers to the monitoring device only. The SENTINEL data is continuously (long-term) transmitted by the phone to a designated server for storage, analysis, decision support, and response by a qualified and dedicated team.
The SENTINEL is intended for use on patients with weighing more than 10 kg (22lbs)
The SENTINEL monitoring device is a dedicated electronic device that records ECG and consists of electronic circuit board, batteries, a plastic enclosure, and lead wires. The data transmission to the smart phone is via low energy Bluetooth transmission. The smart phone mobile device acts as in in-home communication relay, stores the data, and transfers the data via the WEB, using secure communication, to a call center. The Call Center provides a service platform to monitor, analyze, store, and report ECG data sent from the patient.
The provided text describes the ECG SENTINEL System and its review for substantial equivalence to a predicate device, the RhythmStar System. The document focuses on demonstrating that the new device is as safe and effective as the predicate, rather than providing detailed acceptance criteria and a study to prove the device meets these criteria in the traditional sense of a diagnostic performance study.
Instead, the "acceptance criteria" appear to be compliance with various safety and performance standards for medical electrical equipment, and the "study" is a comparison to a predicate device.
Here's an analysis based on the provided text:
1. A table of acceptance criteria and the reported device performance
The document does not present explicit "acceptance criteria" in the form of quantitative performance targets tied to a diagnostic accuracy study. Instead, the performance is demonstrated through compliance with established industry standards and a comparison of features and technical characteristics with a legally marketed predicate device.
| Acceptance Criteria (Implied from Standards & Predicate Comparison) | Reported Device Performance (ECG SENTINEL System) |
|---|---|
| Safety and Essential Performance Standards | |
| AAMI/ANSI/IEC 60601-2-47:2012 (Ambulatory ECG Systems) | Conforms to this standard. |
| AAMI/ANSI ES 60601-1:2005/(R) 2012 & A1:2012 (General Safety) | Conforms to this standard. |
| IEC 60601-1-2, 4th Edition:2014-02 (Electromagnetic Disturbances) | Conforms to this standard. |
| IEC 60601-1-11 Edition 2.0 2015-01 (Home Healthcare Environment) | Conforms to this standard. |
| IEC 62304 Edition 1.1 2015-06 (Medical Device Software) | Conforms to this standard. |
| Functional Performance (Bench Testing) | |
| Ability to record ECG signal | Confirmed. |
| Ability to store data | Confirmed. |
| Ability to transmit data to Call Center | Confirmed. |
| Data can be analyzed at Call Center | Confirmed. |
| Overall performance as designed | Confirmed. |
| Substantial Equivalence (Comparison to Predicate: RhythmStar System (K141813)) | |
| Intended Use | Essentially the same: patients at risk of cardiac disease, requiring continuous monitoring; records ECG, transfers data to server for review by medical professional. |
| Product Code | DXH (Same) |
| Regulation Name and Number | Transmitters And Receivers, Electrocardiograph, Telephone. 21 CFR 870.2920 (Same) |
| Patient population | Adults and Infants weighing more than 10Kg (Same) |
| Environment for Intended Use | Ambulatory, outpatient (Same) |
| Ambulatory ECG performance standards | IEC 60601-2-47:2012 (Same) |
| System Description | 3 off-the-shelf electrodes, patient pendant, cell phone, server, display and reporting (Predicate uses 3 or 5 electrodes, ECG device, server, display and reporting) - Difference: Sentinel uses 2 channels/3 leads, Predicate offers optional 5-lead cable for 3 channels. Not considered a fundamental difference. |
| Basic Technology | Analog ECG front-end, flash data storage, BT transmission to (Android) cell phone, cellular transmission to central server, arrhythmia analysis on central server (Predicate: Analog ECG front-end with Cellular GPRS modem built into device) - Difference: Sentinel uses external mobile phone as bridge to WEB, Predicate has GPRS transmitter built-in. Not considered a fundamental difference. |
| Energy Source | Two non-chargeable Zinc-Air hearing aid batteries (Predicate: Li-Ion externally chargeable battery) - Both require periodic battery replacement. |
| AC Powered | No (Same) |
| Channel Recording | 2 (Predicate: 2 or 3) |
| Bandwidth | 0.5Hz to 35Hz (Predicate: 0.05Hz to 40Hz) - Both provide standard monitoring bandwidth. Predicate's lower frequency is for S-T measurements, but neither provides S-T measurements. |
| Common-mode rejection ratio (CMRR) | Meets IEC60601-2-47 standards (Same) |
| Sampling Rate | Minimum 125 typical 250 Hz (Same) |
| Patient Cable | Built-in 3 lead cable (Predicate: Detachable 3 or 5 lead cable) |
| Lead off Detection | Yes (Same) |
| Accelerometer | No (Predicate: Yes) |
| Data Transmission | Wireless, via mobile network using Android phone (Same) |
| Overall System Design | PEMS and Software (Same) |
| Sterile | Non-sterile (Same) |
| Single Use | No (Same) |
| Arrhythmia Detection Algorithm | On server, only (Predicate: In Device) - Both present analyzed data to medical professional. Not considered a fundamental difference. |
| Alarms | None (Same) |
| User Event Trigger | Continuous Recording and Transmission (Predicate: Algorithm based or user triggered transmission) - Sentinel's continuous transmission allows all events to be seen by medical staff. Not considered a fundamental difference. |
| Battery life | Typically 5 days (Predicate: 72 hours (3 Days)) |
| Dimensions | 7cm x 5cm x 1.5cm (Predicate: 10cm x 6.6cm x 1.3cm) |
| Weight (with battery) | 85 gm (Predicate: 90 gm) |
| Operating temperature | 10 °C to 45 °C (Predicate: 0 °C to 40°C) |
| Transport and storage temperature | -25 °C to 70 °C (Same) |
| Relative humidity | 10 % to 95 %, without condensation (Same) |
2. Sample size used for the test set and the data provenance
The document does not describe a clinical performance study with a "test set" in the context of diagnostic accuracy. The performance testing section mentions "Bench testing verifies that the ECG SENTINEL System can record ECG signal, store data, transmit data to the Call Center, where the data can be analyzed." This suggests laboratory-based functional testing, not a clinical study involving a patient sample size. Therefore, sample size and data provenance for a clinical test set are not applicable here.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
Not applicable. As noted above, there is no clinical diagnostic accuracy test set described.
4. Adjudication method for the test set
Not applicable. There is no clinical diagnostic accuracy test set described.
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 MRMC comparative effectiveness study is mentioned. The device's "ECG analysis algorithm at the Server" flags cardiac activity for review by a medical professional, implying a human-in-the-loop system. However, the document does not include a study comparing human performance with and without AI assistance, nor does it quantify any effect size. The focus is on the device's ability to transmit data for professional review.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
The document describes "an ECG analysis algorithm at the Server" that flags recorded cardiac activity for review. It explicitly states that the analyzed data is presented to a medical professional for review. The system is designed such that the automated analysis serves to flag events for human review, indicating it's not a standalone diagnostic device. The document does not describe a standalone performance evaluation of the algorithm independent of human review.
7. The type of ground truth used
For the bench testing, the ground truth would inherently be the known, controlled electrical signals or simulated ECG patterns injected into the device to verify its basic functionalities (recording, storage, transmission).
For the "ECG analysis algorithm at the Server," the document states that the flagged activity is reviewed by a "medical professional." While the implication is that the professional's review establishes the ground truth for the flagged events, the document doesn't detail any specific ground truth methodology (e.g., expert consensus, pathology, outcome data) for validating the algorithm's flagging accuracy. The goal is to ensure the data is available for review, not necessarily to validate the algorithm's diagnostic accuracy against a definitive ground truth in this submission.
8. The sample size for the training set
Not mentioned. The document focuses on performance relative to standards and a predicate device, not on the development or training of the ECG analysis algorithm.
9. How the ground truth for the training set was established
Not mentioned. As above, the details of the algorithm's training are not provided in this submission.
§ 870.2920 Telephone electrocardiograph transmitter and receiver.
(a)
Identification. A telephone electrocardiograph transmitter and receiver is a device used to condition an electrocardiograph signal so that it can be transmitted via a telephone line to another location. This device also includes a receiver that reconditions the received signal into its original format so that it can be displayed. The device includes devices used to transmit and receive pacemaker signals.(b)
Classification. Class II (performance standards).