(198 days)
The Microlife Upper Arm Automatic Digital Blood Pressure and Cardiovascular Screening Monitor Model WatchBP Office Vascular (TWIN200 VSR) is a non-invasive digital blood pressure device using the oscillometric technique and an upper-arm blood pressure cuff to measure systolic and diastolic blood pressures, pulse rate, mean arterial pressure (MAP) for use in adults and pediatrics (but not neonates) with arm cuff circumference sizes ranging from 14-52 cm (5.5-20.5 inches).
The device can accurately measure in pregnant patients including those with known or suspected preeclampsia.
The device detects the appearance of atrial fibrillation during measurement and gives a warning signal together with the measured blood pressure value if atrial fibrillation is detected.
The device provides aortic blood pressure parameters, including central systolic blood pressure (cSBP), central pulse pressure (cPP) and central diastolic blood pressure (cDBP), non-invasively through the use of a brachial cuff. This was validated against invasive blood pressure measurement and showed that the device determines central blood pressure measurement with high accuracy.
The device provides a validated method for determining the ankle-brachial index (ABI) which may be useful in diagnosing Peripheral Artery Disease (PAD).
The device is only intended to provide a numerical value of brachial-ankle pulse wave velocity (baPWV) for blood flow inside the intended blood vessel, without any diagnosis.
The memory data can be transferred to the PC running the WatchBP Analyzer software by connecting the monitor via USB cable or Bluetooth.
The device is intended for use by healthcare professionals in clinical practice.
Microlife Upper Arm Automatic Digital Blood Pressure Monitor, Model WatchBP Office Vascular (TWIN200 VSR) is designed to measure svstolic and diastolic blood pressure, pulse rate, and mean arterial pressure (MAP) of the "adults and pediatrics (but not neonates)" populations with arm circumference sizes ranging from 14 -52 cm by using a non-invasive technique in which one inflatable cuff is wrapped around the single upper arm. Our method to define systolic and diastolic pressure is similar to the auscultatory method but use a resistive pressure sensor rather than a stethoscope and mercury manometer. The sensor convert tiny alterations in cuff pressure to electrical signals, by analyzing those signals to define the systolic and diastolic blood pressure and calculating pulse rate, mean arterial pressure (MAP), central systolic blood pressure (cSBP), central pulse pressure (cPP) and central diastolic pressure (cDBP) which is a well - known technique in the market called the "oscillometric method".
The device has two settings of measurement. One setting is for measurement on one arm or on both arms simultaneously. The measurement program of the device can be set when the measurement of one arm or both arm is selected, including Number of Measurements. Resting Time (Countdown Time), Interval Time, AFIB Detector, CBP Measurement, and Average Calculation (Discard 1st measurement or not). The other setting is for measurement on one arm with one leq, this measurement is selected when assessing brachial-ankle Pulse Wave Velocity (baPWV) and Ankle Brachial Index (ABI) measurement.
In addition, the device can be used in connection with your personal computer (PC) running the WatchBP Analyzer software. The memory data can be transferred to the PC by connecting the monitor with the PC via USB cable or Bluetooth.
The device can accurately measure blood pressure in pregnant patients including those with known or suspected pre-eclampsia.
The device detects the appearance of atrial fibrillation during measurement and the atrial fibrillation symbol "is displayed on the LCD screen if any atrial fibrillation signal has been detected.
The device provides aortic blood pressure parameters, including central systolic blood pressure (cSBP), central pulse pressure (cPP) and central diastolic blood pressure (cDBP), non-invasively through the use of a brachial cuff.
The device provides a validated method for determining the ankle-brachial index (ABI) which may be useful in diagnosing Peripheral Artery Disease (PAD).
The device is only intended to provide a numerical value of brachial-ankle pulse wave velocity (baPWV) for blood flow inside the intended blood vessel, without anv diagnosis.
The device is for hospital use only.
Here's an analysis of the acceptance criteria and the studies mentioned for the Microlife WatchBP Office Vascular (TWIN200 VSR) device, based on the provided document:
1. Table of Acceptance Criteria and Reported Device Performance
The document doesn't explicitly state numerical acceptance criteria for various performance metrics, except for the implication that the clinical tests were designed to show "substantial equivalence" and "high accuracy" for specific functions. Instead, it leverages the clinical validation of predicate devices for many functions, implying their established performance meets acceptance criteria. For the newly validated feature (baPWV), the performance is described qualitatively.
| Feature | Acceptance Criteria (Implied / Leveraged) | Reported Device Performance |
|---|---|---|
| Brachial BP Measurement | Substantial equivalence to predicate device (K200297) per AAMI/ANSI/ISO 81060-2 | Identical to predicate WatchBP Office (BP3SK1-3B) (K200297). No repeated clinical testing required. |
| AFIB Detection | Substantial equivalence to predicate device (K200297) | Identical to predicate WatchBP Office (BP3SK1-3B) (K200297). No repeated clinical testing required. |
| Central BP (cSBP, cPP, cDBP) | Validated against invasive BP measurement, high accuracy. Substantial equivalence to predicate device (K200297) | Identical to predicate WatchBP Office (BP3SK1-3B) (K200297). Validated against invasive blood pressure measurement and showed high accuracy. No repeated clinical testing required. |
| ABI Assessment | Substantial equivalence to predicate device (K112845) | Identical to predicate WatchBP Office ABI (TWIN200 ABI) (K112845). No repeated clinical testing required. |
| Brachial-Ankle PWV (baPWV) | Clinical feasibility, correlation to age, and comparison to reference cfPWV. | "feasible and observer-independent." "baPWV values differ from those by cfPWV, yet they are closely correlated." The device provides a numerical value for baPWV for blood flow inside the intended blood vessel. |
| Pregnant Patients (incl. pre-eclampsia) | Substantial equivalence to predicate device (K200297) per AAMI/ANSI/ISO 81060-2 | Identical to predicate WatchBP Office (BP3SK1-3B) (K200297). No repeated clinical testing required. |
| Pediatrics (not neonates) | Substantial equivalence to predicate device (K200297) per AAMI/ANSI/ISO 81060-2 | Identical to predicate WatchBP Office (BP3SK1-3B) (K200297). No repeated clinical testing required. |
2. Sample Size Used for the Test Set and Data Provenance
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Brachial-Ankle Pulse Wave Velocity (baPWV) Assessment:
- Sample Size: 97 subjects
- Data Provenance: The document does not specify the country of origin, but it is a "clinical investigation report" (VOL 010.002), implying a prospective study.
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Other features (Brachial BP, AFIB, Central BP, ABI, Pregnant Patients, Pediatrics):
- The document states that the performance of these features are "substantially equivalent" to predicate devices (K200297 and K112845), and thus no repeated clinical testing was required for the WatchBP Office Vascular (TWIN200 VSR). The sample sizes for the original predicate device studies are not provided in this document.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
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Brachial-Ankle Pulse Wave Velocity (baPWV) Assessment:
- The ground truth reference was "reference cfPWV (Complior device)." This is a device, not human experts, used as the gold standard. Therefore, the concept of "number of experts" and their qualifications for establishing ground truth isn't applicable in the traditional sense for this specific test.
-
Other features: The document does not provide details on the ground truth establishment for the predicate devices' clinical studies.
4. Adjudication Method for the Test Set
- Brachial-Ankle Pulse Wave Velocity (baPWV) Assessment: No explicit adjudication method is described. The comparison was automated baPWV vs. Complior device's cfPWV.
- Other features: Not specified for the predicate device studies.
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 study is mentioned. The device is an automatic digital blood pressure monitor, not an AI-assisted diagnostic tool for human readers.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) Was Done
Yes, the device operates in a standalone manner. The measurements (systolic, diastolic, pulse rate, MAP, AFIB detection, cSBP, cPP, cDBP, ABI, baPWV) are determined by the device's algorithms without human intervention in the measurement process itself. The clinical validation of baPWV, for instance, compared the device's output to a reference device.
7. The Type of Ground Truth Used
- Brachial-Ankle Pulse Wave Velocity (baPWV) Assessment: The ground truth for baPWV was established by a reference device: cfPWV (Complior device). This is a form of device-based reference standard, often considered a clinical reference standard in this domain.
- Central Blood Pressure (cSBP, cPP, cDBP): Stated to be "validated against invasive blood pressure measurement," which is a clinical reference standard/gold standard for blood pressure.
- Other features (Brachial BP, AFIB, ABI, Pregnant Patients, Pediatrics): Not explicitly stated in this document for the predicate studies, but for blood pressure monitors, the typical ground truth involves auscultation by trained observers or invasive measurements by clinicians.
8. The Sample Size for the Training Set
The document does not provide information about a "training set" for an AI or machine learning model. The device's core oscillometric technology and algorithms are described as similar to or identical to existing predicate devices, implying a long history of algorithm development rather than a modern machine learning training approach with a distinct training set.
9. How the Ground Truth for the Training Set Was Established
As no training set is described for an AI/ML model, this information is not provided. The algorithms are based on established oscillometric principles and prior clinical validations of predicate devices.
§ 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).