(144 days)
INVU by Nuvo™ is a maternal-fetal monitor that non-invasively measures and displays fetal heart rate (FHR), maternal heart rate (MHR) and Uterine Activity (UA).
The INVU Sensor Band™ acquires the fetal heart electrocardiogram and maternal heart electrocardiogram signals from abdominal surface electrodes and the fetal phonocardiogram and the maternal phonocardiogram signals from surface acoustic sensors. The FHR, MHR and UA tracings are derived from these signals and presented.
INVU by Nuvo™ is indicated for use by pregnant women who are in their 32nd week of gestation (or later), with a singleton pregnancy.
The INVU by Nuvo™ maternal-fetal monitor is intended for use by healthcare professionals in health care facilities and by the patient in the patient's home, on the order of a physician.
The INVU by Nuvo™ is indicated for antepartum fetal surveillance (i.e. non-stress testing).
This system does not prevent the onset of preterm labor nor will it prevent the occurrence of preterm birth.
INVU by Nuvo™ is a non-invasive medical device that acquires and displays vital signs of the pregnant woman and her fetus. It measures and processes signals picked up on the abdominal surface using highly sensitive sensors, special electronic circuitry, and processing software. Two types of sensors pick up the signals: ECG-like sensors that pick-up bio-potential signals, and acoustic sensors. The bio-potential (ECGlike) sensors pick up the fECG (of the fetus), the mECG signals (of the pregnant woman) and the acoustic sensors measure the sounds from the pregnant woman's abdomen (PCG -phonocardiogram and fPCG fetal PCG). The FHR, MHR, and UA tracings are derived from these signals and presented.
lt is an integrated platform that uses a signal acquisition tool to provide input related to fetal heart rate (FHR), maternal heart rate (MHR), to two separate software applications, one for the patient (INVU App) and one for the physician (INVU-Pro application), which also provides uterine activity (UA) tracings. Sensors are incorporated in a belt that is worn on the abdomen of the pregnant woman, where it acquires both biopotential and acoustic signals. The signals are processed at a cloud-server level.
The sensors are attached to the pregnant woman's abdomen by a belt (INVU by Nuvo™ sensory band). An integrated electronic module receives, processes and transmits the measured data to algorithmic modules at cloud servers, where the inputs from the sensors are processed, merged, and sent to the INVU by Nuvo™ (patient) application to display the average MHR after a 30 minute (minimum) monitoring session and to the INVU by Nuvo™ Pro (physician) application to display the complete FHR, MHR, and uterine activity data from a monitoring session can only be scheduled by a health care provider.
Here's a breakdown of the acceptance criteria and the study proving the device meets them, based on the provided text:
Device: INVU by Nuvo™ (Maternal-fetal monitor)
Performance Metrics of Interest for this Documentation: Uterine Activity (UA) detection. The text mentions FHR and MHR performance was addressed in a prior K-submission (K191401), so this summary focuses on UA as per the provided study details.
1. Table of Acceptance Criteria and Reported Device Performance
| Parameter/Metric | Acceptance Criteria (Performance Goal) | Reported Device Performance (INVU by Nuvo™) | Context for Comparison (TOCO Device) |
|---|---|---|---|
| Positive Percent Agreement (PPA) with IUPC (Gold Standard) | Lower 95% Confidence Bound of PPA > 75% | 84.80% (95% CI: [81.58%; 88.02%]) | 37.50% (95% CI: [28.23%; 46.77%]) |
| False Positive Rate (FPR) with IUPC (Gold Standard) | Not explicitly stated as a numerical acceptance criterion, but implicitly evaluated for comparability. | 24.28% (95% CI: [20.46%; 28.11%]) | 10.69% (95% CI: [5.65%; 15.72%]) |
Conclusion from Table: INVU by Nuvo™ met its performance goal for Positive Percent Agreement. The False Positive Rate was higher than the TOCO device, but the overall conclusion stated that INVU™ is comparable to the standard of care TOCO device and meets the required accuracy for its intended use.
2. Sample Size and Data Provenance
- Test Set Sample Size: 80 (Validation Phase)
- Data Provenance: Not explicitly stated regarding country of origin. The study was a "pivotal clinical study," suggesting it was prospective.
3. Number of Experts and Qualifications for Ground Truth
- Number of Experts: Not specified.
- Qualifications of Experts: Not specified. (The ground truth was established by a medical device, IUPC, not human experts for this specific test.)
4. Adjudication Method for the Test Set
- Adjudication Method: Not applicable/None mentioned for the UA data itself. The ground truth for Uterine Activity was established directly by an Internal Uterine Pressure Catheter (IUPC), which is the "gold standard" device. There's no indication of human adjudication of this instrumental ground truth.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- Was an MRMC study done? No. This study focuses on the device's accuracy in detecting Uterine Activity compared to an instrumental gold standard and a standard-of-care device. It does not evaluate human reader improvement with or without AI assistance.
6. Standalone (Algorithm Only) Performance
- Was a standalone performance study done? Yes. The study directly assessed the INVU by Nuvo™ platform's ability to collect and display UA data and compared its performance (specifically the algorithm's output) against the IUPC (gold standard) and TOCO devices.
7. Type of Ground Truth Used
- Type of Ground Truth: Instrumental Gold Standard. Uterine activity was measured by an Internal Uterine Pressure Catheter (IUPC), which is explicitly referred to as the "gold standard" for uterine activity measurement.
8. Sample Size for the Training Set
- Training Set Sample Size: 40
9. How the Ground Truth for the Training Set was Established
- Method for Training Set Ground Truth: The text states, "During the training phase, uterine activity data was collected to 'train' the UA algorithm to identify uterine contractions." While not explicitly stated, it is highly implied that the same method for ground truth establishment as the validation phase (IUPC) would have been used to provide accurate Uterine Activity data for algorithm training.
§ 884.2730 Home uterine activity monitor.
(a)
Identification. A home uterine activity monitor (HUAM) is an electronic system for at home antepartum measurement of uterine contractions. The HUAM system comprises a tocotransducer and an at-home recorder. This device is intended for use in women with a previous preterm delivery to aid in the detection of preterm labor.(b)
Classification. Class II (special controls); guidance document (Class II Special Controls Guidance for Home Uterine Activity Monitors).