(61 days)
The Cambridge Heart MTWA OEM Module is intended for the recording of electrocardiograms, vector cardiograms and measurement of Microvott T-Wave Alternans* at rest and during ECG stress testing.
The presence of Microvolt T-wave Atternans as measured by the Analytic Spectral Method of the MTWA OEM Module in patients with known, suspected or at risk of ventricular tachyarrhythmia predicts increased risk of a cardiac event (ventricular tachyarrhythmia or sudden death).
The MTWA OEM Module should be used only as an adjunct to clinical history and the results of other non-invasive and/or invasive tests. The interpretive results of the MTWA OEM Module should be reviewed by a qualified physician.
The predictive value of T-wave Alternans for cardiac events has not been established in patients with active, untreated ischemia.
*Microvolt T-wave Alternans is defined as T-wave alternans which (a) is measured from highresolution multi-segment sensors, (b) is present in leads X, Y, Z, VM or two adjacent precordial leads, (c) is at the level of 1.9 microvolts after signal optimization of the background noise level, (d) is at least three standard deviations greater than the background noise level, (e) has an onset heart rate at or below 110 beats per minute, and (f) is sustained for all heart rates above the onset heart rate
The MTWA OEM Module consist of a patient module and an analysis software operating on a PC platform meeting the technical requirement specified in Product Requirement Document (PRD) for the module. The MTWA OEM Module is intended for the recording of electrocardiograms, vector cardiograms and measurement of Microvolt T-Wave Alternans* at rest and during ECG stress testing. The alternans levels reported in K983012, K001034, K003492 and K022149, K050225 were measured using the Analytic Spectral Method. This method consists of several computational steps that combine to form a unique analytical process. The Microvolt T-wave Alternans measurement, the output of this specific process, has been shown to be useful in predicting ventricular tachyarrhythmias and sudden cardiac death.
The Cambridge Heart MTWA OEM Module provides T-wave alternans diagnostic capabilities to standard stress labs. The Analytic Spectral Method of Alternans Processing used in the Cambridge Heart MTWEA OEM Module is intended for the measurement of microvolt T-Wave alternans at rest and during treadmill, ergometer and pharmacologic stress testing.
The Alternans test using the Cambridge Heart MTWA OEM Module is performed with seven standard stress test electrodes and seven proprietary multi-segment Micro-V Alternans™ Sensors. The electrodes and sensors are attached through a leadwire set to the belt-worn Patient module, which provides digitized data to the MTWA OEM Module.
The provided document is a 510(k) premarket notification summary for the Cambridge Heart MTWA OEM Module. It focuses on demonstrating substantial equivalence to a predicate device (HearTwave II Cardiac Diagnostic System K050225) rather than providing a detailed study proving the device meets specific acceptance criteria with performance metrics.
Therefore, many of the requested details about acceptance criteria, sample sizes, ground truth establishment, expert qualifications, and MRMC studies are not explicitly stated in this type of regulatory submission. The submission primarily emphasizes that the new device uses the same analytical method and software as its predicate and that validation confirmed identical performance.
Here's the information that can be extracted or inferred from the document, along with what is not provided:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Primary Goal: Substantial Equivalence to predicate device HearTwave II Cardiac Diagnostic System (K050225) | The MTWA OEM Module's performance is identical to its predicate device (HearTwave II Cardiac Diagnostic System, K050025). |
| Specific Performance Parameters (Inferred/Validated): |
- Data Management capability
- Main Application and Processing Screens functionality
- Printing functionality
- System Setup & Configuration
- MTWA Algorithm results
- ECG Processing
- Overall System Performance | Validation parameters verified that all compatibility requirements are met and that the performance of the Cambridge Heart TWA OEM module is identical to its predicate device. |
| Clinical Efficacy (as per Indications for Use): - Prediction of increased risk of a cardiac event (ventricular tachyarrhythmia or sudden death) in patients with known, suspected, or at risk of ventricular tachyarrhythmia. | The Microvolt T-wave Alternans measurement, the output of this specific process, has been shown to be useful in predicting ventricular tachyarrhythmias and sudden cardiac death. (This relies on prior studies of the predicate device/method, not new performance data in this submission). |
2. Sample size used for the test set and the data provenance
- Sample Size for Test Set: Not explicitly stated. The validation involved testing the OEM Module incorporated into the Cardiac Science Q-Stress System (K082173). The document mentions "Validation parameters verified that all compatibility requirements are met and that the performance... is identical," but does not detail the size or nature of the test dataset used for this validation.
- Data Provenance: Not explicitly stated for specific validation data. The prior clinical utility of the Analytic Spectral Method was established in previous 510(k) submissions (K983012, K001034, K003492, K022149, K050225), which would have involved clinical data, but the specifics of that data (country of origin, retrospective/prospective) are not in this summary.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Not stated. The validation focused on functional and performance identity with the predicate, not on clinical ground truth establishment for a diagnostic study using expert consensus. The "interpretive results of the MTWA OEM Module should be reviewed by a qualified physician," but this is a statement about clinical use, not about expert input for ground truth in a validation study.
4. Adjudication method for the test set
- Not stated.
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
- A MRMC comparative effectiveness study was not reported in this document. The device is a quantitative measurement tool (Microvolt T-Wave Alternans) designed to predict risk, not a direct "AI assistance" tool for human readers in the sense of image interpretation.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Yes, the performance validation of the "MTWA Algorithm" and "ECG Processing" was part of the overall system validation. The core of the device is the automated measurement of Microvolt T-Wave Alternans using the Analytic Spectral Method. The document states its output "has been shown to be useful in predicting ventricular tachyarrhythmias and sudden cardiac death," implying standalone algorithmic performance. However, the device is explicitly intended "as an adjunct to clinical history and the results of other non-invasive and/or invasive tests" and its results "should be reviewed by a qualified physician," meaning it's not designed for fully standalone clinical decision-making.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- For the validation performed for this 510(k), the "ground truth" was likely the expected output/performance of the predicate device (K050225) on identical inputs, ensuring the new module produced the same analytic results.
- For the clinical utility of the Analytic Spectral Method in predicting cardiac events (which this device inherits from its predicate), the ground truth in those foundational studies would have been outcomes data (e.g., occurrence of ventricular tachyarrhythmia or sudden death over a follow-up period).
8. The sample size for the training set
- Not applicable/Not stated. This submission is for a modification of an existing device/algorithm. It leverages an established analytical method (Analytic Spectral Method) and therefore doesn't explicitly describe a new "training set" for a de novo AI model. The method itself was likely developed and "trained" on various ECG datasets historically, but those details are not in this document.
9. How the ground truth for the training set was established
- Not applicable/Not stated, as this submission doesn't detail the training of a new algorithm. For the original development of the Analytic Spectral Method, the ground truth for its development would have involved correlating T-wave alternans measurements with cardiac event outcomes, likely established through extensive clinical research and data collection where "ground truth" was determined by clinical event follow-up.
§ 870.1425 Programmable diagnostic computer.
(a)
Identification. A programmable diagnostic computer is a device that can be programmed to compute various physiologic or blood flow parameters based on the output from one or more electrodes, transducers, or measuring devices; this device includes any associated commercially supplied programs.(b)
Classification. Class II (performance standards).