(262 days)
The CSF-4 is intended to record, store, transfer, and display single-channel electrocardiogram (ECG) rhythms. The ECG signal is for quality checks of the data and for manual interpretation of heart rate. The CSF-4 also measures, records and displays pulse rate.
The CSF-4 is also indicated for use in measuring and displaying functional oxygen saturation of arterial hemoglobin (SpO2). The CSF-4 is for adult patients and health-conscious individuals in hospitals, clinics, long-term care facilities, and homes. The CSF-4 is a prescription device and should be used under the care of a physician. CSF-4 does not provide any alarms. It is not intended for pediatric use or use in critical care settings. The device is not intended to provide outputs during periods of motion.
The CSF-4 is a non-invasive system comprised of software, hardware and mechanical components that enables the user to measure electrocardiography (ECG) and oxygen saturation of arterial hemoglobin (SpO2), as well as measuring pulse rate using photoplethysmography (PPG).
CSF-4 is a single-patient use, wearable monitoring device that collects intermittent data of physiological parameters, when little to no motion is detected.
The CSF-4 is comprised of 3 main components;
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- CS Watch 3 with CSF-4 Watch firmware ("Watch"): The CS Watch 3 is a wrist worn device embedded with non-invasive sensors. The watch includes firmware that activates the sensors, synchronizes the data sampled by the sensors, processes the data, stores the processed data in nonvolatile memory, and provides the data to the user. The processed data is transferred to the Mobile App via a secured BLE communication channel. In addition, the watch sends real-time raw data signals to the Mobile App.
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- CSF-4 Mobile Application ("Mobile App"): The Mobile App works on both Android OS and iOS. The mobile app communicates with the watch via BLE and to the Cloud App via HTTPS, thus acting as the watch gateway to the cloud application. The Mobile App caches the processed data from the watch and transfers it to the cloud application. It allows the user to conveniently view the measurement results and real time raw data. The Mobile App provides the user with the capability of creating an on-demand report and sharing it using 3rd party sharing applications.
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- CSF-4 Cloud Application ("Cloud App"): The Cloud App securely stores the user and processed data over designated databases. It provides the mechanism of creating and sending periodical reports which are sent to the user's email both automatically and on-demand.
The provided text describes the acceptance criteria and study proving the device meets those criteria, specifically for the CardiacSense CSF-4 device. The information is extracted from the 510(k) Summary.
Here's a breakdown of the requested information:
1. Table of acceptance criteria and the reported device performance
Based on the "SUMMARY OF NON-CLINICAL TESTING" and "SUMMARY OF CLINICAL TESTING" sections:
| Feature/Parameter | Acceptance Criteria (Implicit from testing methodology or standards) | Reported Device Performance |
|---|---|---|
| QRS Detection (ECG) | Sensitivity & PPV > 98% (MIT-BIH Arrhythmia & AHA) | |
| Sensitivity & PPV > 93% (MIT-BIH Noise Stress) | MIT-BIH Arrhythmia & AHA: Sensitivity > 98%, PPV > 98% | |
| MIT-BIH Noise Stress: Sensitivity > 93%, PPV > 93% | ||
| Heart Rate (HR) RMS Accuracy (ECG) | RMS Accuracy ~1-2% (MIT-BIH Arrhythmia & AHA) | |
| RMS Accuracy ~3% (MIT-BIH Noise Stress) | MIT-BIH Arrhythmia & AHA: RMS accuracy varies between 1-2% | |
| MIT-BIH Noise Stress: RMS accuracy slightly above 3% | ||
| Pulse Oximeter (SpO2) Accuracy | Accuracy as per ISO 80601-2-61:2017 standard (implied) | 2.96% accuracy (SpO2 range 70% to 100%) |
| ECG Validation (overall performance) | (Not explicitly stated as numerical criteria, but performance validated) | Sensitivity of 99.59%, False Detection Rate of 0.54% |
| PPG Validation (overall performance) | (Not explicitly stated as numerical criteria, but performance validated) | Sensitivity of 99.78%, False Detection Rate of 0.03% |
Note: For QRS detection and HR accuracy, the "acceptance criteria" are implied by the reported performance relative to the standards. For SpO2, it's explicitly linked to the ISO standard. For overall ECG and PPG validation, specific numerical criteria were not explicitly stated as "acceptance criteria" but rather as "performance."
2. Sample sizes used for the test set and the data provenance
- QRS Algorithm (Bench Testing): Evaluated against three databases: MIT-BIH Arrhythmia, AHA, and MIT-BIH Noise Stress. The specific sample sizes (number of recordings/patients) for each database are not provided in this document, only that the evaluation was "per recording and per database."
- Pulse Oximeter Testing:
- Sample Size: n=234 samples.
- Data Provenance: Conducted at the Hypoxia Research Laboratory, Department of Anesthesia Perioperative Care, University of California at San Francisco (UCSF). This is a prospective clinical study based on the context.
- ECG and PPG Validation:
- Sample Size: Not explicitly stated, but the study was conducted at Fairview Research Center of the University of Minnesota. This was part of a previous submission (CSF-3) and was "reviewed and accepted by the Agency." This suggests it was likely a prospective clinical study.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
The document does not explicitly state the number or qualifications of experts used to establish the ground truth for any of the tests.
- For QRS algorithm testing, the ground truth for the MIT-BIH Arrhythmia and AHA databases is inherently part of those standardized, expert-annotated datasets.
- For Pulse Oximeter Testing, the ISO 80601-2-61:2017 standard typically specifies requirements for a reference oximeter and a clinical study setup, implying a highly controlled environment with medical professionals overseeing the reference measurements, but specific expert involvement for ground truth adjudication is not detailed here.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
The document does not specify any adjudication methods (like 2+1 or 3+1) used for establishing ground truth for the test sets.
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
The document mentions that the ECG signal is for "manual interpretation of heart rate." However, there is no mention of an MRMC comparative effectiveness study, nor any data on how human readers improve with AI vs. without AI assistance. The testing focuses on the device's standalone performance.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Yes, standalone performance was assessed for the following:
- QRS Algorithm Performance: Evaluated against standardized databases (MIT-BIH Arrhythmia, AHA, MIT-BIH Noise Stress) - this is algorithm-only performance.
- Pulse Oximeter Testing: The device's SpO2 accuracy was validated against reference measurements, indicating standalone performance.
- ECG and PPG Validation: The reported sensitivity and false detection rates for ECG and PPG suggest standalone algorithmic performance.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- QRS Algorithm: The ground truth for the MIT-BIH Arrhythmia and AHA databases is typically derived from expert-annotated ECG waveforms.
- Pulse Oximeter Testing: The ground truth for SpO2 measurements typically comes from a reference oximeter or blood gas analyzer in a controlled clinical setting, as dictated by the ISO 80601-2-61:2017 standard.
- ECG and PPG Validation: While not explicitly stated, clinical validation of ECG and PPG typically involves comparison to a gold standard, which for ECG could be a 12-lead ECG interpreted by cardiologists, and for PPG related to a reference heart rate/pulse measurement.
8. The sample size for the training set
The document does not provide any information regarding the training set size for the algorithms within the CSF-4 device. It focuses solely on the validation/test procedures and results.
9. How the ground truth for the training set was established
Since information on the training set is not provided, details on how its ground truth was established are also not available in the provided text.
§ 870.2340 Electrocardiograph.
(a)
Identification. An electrocardiograph is a device used to process the electrical signal transmitted through two or more electrocardiograph electrodes and to produce a visual display of the electrical signal produced by the heart.(b)
Classification. Class II (performance standards).