(164 days)
Masimo W1™ and the integrated Masimo W1 Module are intended to record, store and transfer single-channel electrocardiogram (ECG) rhythms. The Masimo W1 also displays ECG rhythms, and the Masimo W1 Module detects the presence of atrial fibrillation. The Masimo W1 and the integrated Masimo W1 Module are intended for use by healthcare professionals, patients with known or suspected heart conditions, and health-conscious individuals.
Masimo W1 Module ECG software is an over-the-counter (OTC) software that operates on the Masimo W1 Module that can be used with compatible watches (e.g., Masimo W1). The software is intended to create, record, store, transfer, and display a single channel electrocardiogram (ECG) for informational use only in adults 22 years and older. It supports the classification of either atrial fibrillation (AFib) or sinus rhythm with the intention of aiding heart rhythm identification; it is not intended to replace traditional methods of diagnosis or treatment. The software is not intended for users with other known arrhythmias and users should not interpret or take clinical action based on the device output without consultation of a qualified healthcare professional.
The Masimo W1™ and the integrated Masimo W1 Module are also intended for the spot-checking of functional oxygen saturation of arterial hemoglobin (SpO2) and pulse rate (PR). The Masimo W1 and the integrated Masimo W1 Module are indicated for adults in hospitals, clinics, long-term care facilities, and homes.
The Masimo W1 is a watch that incorporates the Masimo W1 Module, which is the device that is responsible for the physiological signal detection and algorithm used to support the different parameters. The Masimo W1 Module incorporates spot check ECG functionality and Masimo SET Pulse Oximetry technology so that it can provide both ECG and Masimo SET pulse oximetry parameters. As part of this submission, Masimo is requesting clearance for an automated atrial fibrillation "AFib" Classification Feature that is used to analyze the single channel ECG waveform.
The parameter outputs from the Masimo W1 Module are communicated and displayed on the watch screen so that the data can be viewed and recorded. Masimo W1 also supports wireless communication of monitored data to a compatible smart device application. The sharing of the parameter data to the applications allows the users to see and track their data using their smart phones. Smart phone applications can also help to share information to caregivers and healthcare professionals.
Here's a breakdown of the acceptance criteria and the study that proves the device meets them, based on the provided FDA 510(k) Clearance Letter for the Masimo W1 with the Atrial Fibrillation (AFib) Classification Feature:
1. Table of Acceptance Criteria and Reported Device Performance
For the Atrial Fibrillation Classification Feature:
| Performance Metric | Acceptance Criteria (Not explicitly stated as "acceptance criteria" but implied by comparison to predicates and clinical study results) | Reported Device Performance (Masimo W1 with AFib Classification Feature) |
|---|---|---|
| Atrial Fibrillation (AFib) Classification | ||
| Sensitivity | Comparable to or better than predicate devices (Withing Scan Monitor: 96.3%; Samsung ECG Monitor: 98.1%) | 99.3% [96.3%, 100%] |
| Specificity (Sinus Rhythm) | Comparable to or better than predicate devices (Withing Scan Monitor: 100%; Samsung ECG Monitor: 100%) | 100% [97.8%, 100%] |
| Positive Predictive Value (PPV) | (Not explicitly compared in table, but reported as a key performance metric) | 100% [97.5%, 100%] |
| Unclassified Rate | (Not explicitly compared in table) | 5.0% |
| Noise Rate | (Not explicitly compared in table) | 1.7% |
| ECG Waveform Quality Analysis | ||
| Qualitative Agreement (with 12-lead ECG Lead I) | High agreement by qualified clinicians | 98% [96% - 98%] |
| Quantitative Similarity (Key ECG features like QRS amplitude, QRS width) | Similar to Lead I of a gold-standard 12-lead ECG reference | Similar to Lead I of a gold-standard 12-lead ECG reference |
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Sample Size: The document states "Prospective clinical testing was conducted to validate the AFib Classification Feature on adult subjects from 4 different sites." While a specific number of subjects is not provided, it indicates a multi-site study.
- Data Provenance: Prospective clinical testing. The country of origin is not explicitly stated in the provided text.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
- Number of Experts: Unspecified (referred to as "qualified clinicians" for the qualitative assessment of ECG waveforms).
- Qualifications of Experts: "Qualified clinicians" were used for the qualitative assessment of the ECG waveforms. Further specific qualifications (e.g., cardiologist, years of experience) are not detailed in the provided text.
4. Adjudication Method for the Test Set
The document does not explicitly state the adjudication method used for establishing the ground truth for the test set (e.g., 2+1, 3+1). It only mentions that "qualified clinicians" made an agreement assessment.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- Was it done? No, a multi-reader multi-case (MRMC) comparative effectiveness study comparing human readers with AI assistance versus without AI assistance was not described in the provided text. The study focused on the standalone performance of the AI AFib classification feature and the quality of its ECG waveform compared to a gold standard.
- Effect Size: Not applicable, as an MRMC study was not described.
6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study
- Was it done? Yes, a standalone performance study was clearly conducted for the AFib Classification Feature. The "Masimo W1 ECG AFib Classification feature Performance" section directly reports sensitivity, specificity, and PPV for the algorithm's output. The "Masimo W1 Module ECG software" is described as supporting the classification, indicating an algorithmic assessment.
7. Type of Ground Truth Used
- For AFib Classification: The gold standard for AFib classification is not explicitly stated, but clinical validation for ECG rhythm typically uses expert-adjudicated 12-lead ECG recordings. The document mentions "comparing similarity between Masimo W1 and gold-standard 12 lead ECG as reference" for waveform quality, which strongly implies 12-lead ECGs were used as a reference for rhythm classification as well.
- For ECG Waveform Quality: Gold-standard 12-lead ECG as reference.
8. Sample Size for the Training Set
The document does not specify the sample size for the training set. It only describes the test set used for clinical validation.
9. How the Ground Truth for the Training Set Was Established
The document does not specify how the ground truth for the training set was established. It focuses solely on the validation/test set.
§ 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).