(203 days)
The SphygmoCor Px is indicated for use in those patients where information related to the ascending aortic pressure is desired, but in the opinion of the physician, the risks of the intra-arterial radial artery pressure recording procedure may outweigh the benefits of using the SphygmoCor Mx system with an invasive radial pressure input.
The SphygmoCor Px provides a derived ascending aortic blood pressure waveform and a range of central arterial indices. The SphygmoCor is used with a tonometer over the radial artery calibrated with a standard cuff blood pressure measurement. It is to be used in those patients where information related to the ascending aortic pressure is desired but in the opinion of the physician, the risks of the cardiac catheterization procedure or other invasive monitoring may outweigh the benefits.
The SphygmoCor SCOR-Px is a computerized tool for the assessment of blood pressure. The SphygmoCor can calculate the calibrated ascending aortic pressure probater - 110 g the radial artery pressure waveform recorded non-invasively from a radial artery tonometer and a brachial cuff measurement.
An eight-second segment of the radial artery pressure signal is processed in the SphygmoCor electronics module to derive the calibrated ascending aorta pressure waveform and to derive central pressure waveform parameters.
The signal processing electronics module is attached to a PC computer through a serial RS-232C port.
The patient's study report appears on the PC computer and displays the measured (radial) and calculated (central) waveforms, allows input of patient information, and provides the operator with instructions. It uses an IBM-compatible computer (notebook or desktop) to run the SphygmoCor computer software suite.
Here's an analysis of the provided text regarding the SphygmoCor Px device, addressing your specific questions, with the caveat that the supplied document is a 510(k) summary and not a full study report, so some details are not explicitly stated.
The SphygmoCor Px is a computerized tool designed to provide calibrated central aortic pressure waveforms non-invasively. It achieves this by using a non-invasive tonometer over the radial artery, calibrated with a conventional brachial cuff measurement. Its primary function is to derive the central aortic blood pressure waveform and associated arterial indices.
Acceptance Criteria and Device Performance:
The document focuses on demonstrating substantial equivalence to a predicate device (SphygmoCor Mx) rather than specific numerical acceptance criteria for performance metrics like accuracy, sensitivity, or specificity. The core acceptance criterion for the SphygmoCor Px is that its non-invasive radial artery waveform acquisition method is substantially equivalent to the invasive method used by the predicate device for generating central aortic pressure waveforms.
| Acceptance Criterion (Implicit) | Reported Device Performance |
|---|---|
| Substantial equivalence of non-invasive radial artery pressure waveforms to invasively measured waveforms. | A study by Kelly et al. "demonstrated that the two sets of input radial artery waveforms are substantially equivalent." This implies that the waveforms acquired non-invasively by the SphygmoCor Px system (using the Millar tonometer and brachial cuff calibration) are comparable enough to the invasively acquired waveforms (using a catheter in the radial artery by the SphygmoCor Mx) such that the subsequent signal processing (which is the same for both devices) yields equivalent central aortic pressure waveforms. The document also cites "other publications, and the experience of the clearance of the Colin 7000 and the Millar tonometer itself" as further support for substantial equivalence. |
| Compliance with electrical and environmental safety standards. | The entire system "has been tested to demonstrate compliance with IEC-601-1 (including its subparagraphs) Electro-Medical Equipment Safety Standard" for input voltages of 110 and 220 volts. This demonstrates the device meets safety standards for safe use. |
Study Details:
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Sample Size Used for the Test Set and Data Provenance:
- Sample Size: The provided text does not specify the sample size for the Kelly et al. study.
- Data Provenance: The document implies the study was conducted by Kelly et al., but does not state the country of origin of the data. The study compared invasive and non-invasive radial artery pressure waveforms. Given the nature of medical device development, it's highly likely to be a prospective study designed for this comparison.
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Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications:
- The document does not mention the use of experts to establish ground truth for the test set in the way often seen for AI/image analysis devices. The comparison is between two methods of acquiring radial artery waveforms, with the invasive catheter measurement serving as the de facto "ground truth" for waveform acquisition. Therefore, a separate expert consensus for the test set, beyond the physician's role in performing the invasive procedure, is not described or apparently necessary for this type of comparison.
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Adjudication Method for the Test Set:
- Given the nature of the comparison (invasive vs. non-invasive waveform acquisition), adjudication methods like 2+1 or 3+1 are not applicable and are not mentioned. The comparison is objective, based on signal analysis.
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Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
- No, an MRMC comparative effectiveness study was not performed or described. The device is a "Blood Pressure Computer" that calculates a waveform, not an diagnostic imaging device where human readers interpret outputs. The comparison is at the level of the input data (radial artery waveforms).
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Standalone Performance (Algorithm Only without Human-in-the-Loop Performance):
- The document implies a standalone performance comparison in the context of the Kelly et al. study. The comparison is specifically between the invasively acquired radial waveform and the non-invasively acquired radial waveform. The SphygmoCor Px then processes the non-invasive waveform using the same signal processing software as the predicate device (SphygmoCor Mx). Therefore, the "algorithm only" performance is assessed by confirming the equivalence of the input waveforms to this shared algorithm. Once the input is equivalent, the algorithmic output is assumed to be equivalent.
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Type of Ground Truth Used:
- The ground truth for the comparison in the Kelly et al. study implicitly involves invasively measured radial artery pressure waveforms acquired via catheter. This is considered the gold standard for direct arterial pressure measurement.
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Sample Size for the Training Set:
- The document does not mention a separate "training set" as one would typically see for machine learning or AI models. The SphygmoCor Px uses existing signal processing software that was presumably developed and validated over time. The Kelly et al. study is a validation study comparing the input data streams, not a training study for the algorithm itself.
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How the Ground Truth for the Training Set Was Established:
- As there's no explicitly mentioned "training set" for the SphygmoCor Px's algorithm, this question is not directly applicable to the information provided. The signal processing algorithms for deriving central aortic pressure waveforms were likely developed and validated against invasive central aortic pressure measurements (e.g., from cardiac catheterization) in previous research, which forms the basis for both the SphygmoCor Mx and Px. However, the details of that initial algorithm development and validation are not supplied in this 510(k) summary.
§ 870.1130 Noninvasive blood pressure measurement system.
(a)
Identification. A noninvasive blood pressure measurement system is a device that provides a signal from which systolic, diastolic, mean, or any combination of the three pressures can be derived through the use of tranducers placed on the surface of the body.(b)
Classification. Class II (performance standards).