(102 days)
The Sensi device consisting of the Sensi Diagnostic Heart Murmur Software, the WelchAllyn Master Elite Stethoscope and WelchAllyn USB Analyzer is a decision support device intended to be used on a single patient to assist the medical examiner in analyzing cardiac sounds for the identification and classification of suspected murmurs. It is used to distinguish between normal/physiological and pathological heart murmurs by recording the acoustic signal of the heart and the ECG signal simultaneously and analyze these signals. The acoustic heart signal is analyzed to identify specific heart sounds that may be present. Identified sounds include S1, S2, and suspected systolic murmurs.
Sensi indicates whether or not a recorded heart sound contains a suspected heart murmur and the confidence with which the analysis was made The device must be used in a clinical setting by trained personnel with the prescribed accessories and all relevant patient information must be taken into consideration before a diagnosis is made.
The interpretations of heart sounds offered by the Sensi device are only significant when used in conjunction with physician over-read as well as consideration of all other relevant patient data.
Sensi is not intended to be a diagnostic device. It does not supersede the judgment of the qualified medical personnel. The device is intended to aid the physician in the evaluation of heart sounds. The physicians responsible for reviewing and interpreting the results, along with the auscultatory findings and medical history, in making a referral decision.
The Sensi with Diagnostic Heart Murmur Software is a decision support device intended to acquire, record, and analyze heart sounds. It is used to distinguish between normal/physiological and pathological heart murmurs by recording the acoustic signal of the heart and the ECG signal simultaneously and analyzing these signal.
The complete system is a CD comprising Sensi Diagnostic Heart Murmur Software that runs on a computer with Windows operating system, instructions for use, the WelchAllyn Master Elite Stethoscope and the WelchAllyn Meditron Analyzer that captures the acoustic heart and ECG signals.
The Sensi Diagnostic Heart Murmur Software distinguishes between normal/ physiological and pathological heart murmurs by analyzing the acoustic heart and ECG signals captured with the WelchAllyn Meditron Analyzer. The device will record the acoustic sound of the heart at the four main auscultation positions and a three lead ECG signal. The ECG signal is not intended for diagnostic use, only to synchronize with the beginning of each heart cycle. The acoustic heart signal is analyzed to identify heart sounds that may be present, identified sounds include S1, S2 and suspected systolic murmurs.
Here's an analysis of the provided text regarding the acceptance criteria and the study proving the device meets them:
1. Table of Acceptance Criteria and Reported Device Performance:
The document doesn't explicitly state quantitative "acceptance criteria" for the Sensi device in a tabular format as a prerequisite for clearance. Instead, it reports performance metrics from comparative and validation studies. The primary comparative study focuses on overall accuracy, while another section mentions specificity and sensitivity for a "CAA algorithm." It's important to note that the document highlights the device's equivalence to predicate devices rather than setting new, specific performance thresholds for clearance.
| Acceptance Criterion (Implied) | Reported Device Performance |
|---|---|
| Overall Accuracy (compared to Zargis Cardioscan) | Sensi: 70.8% |
| Cardioscan: 67.9% | |
| Specificity (of a CAA algorithm, possibly a component of Sensi) | 94% |
| Sensitivity (of a CAA algorithm, possibly a component of Sensi) | 91% |
| Usability (scored by intended users) | On average, all users scored Sensi Software usability more than 4 out of 5 |
| Graphical User Interface (GUI) and Usability (compared to others) | Sensi compares favorably to three other comparable software programs |
| Distinguishing functional vs. pathological murmurs in pediatrics | 1568 heart sounds met criteria of good quality and matched recorded pathological condition. |
2. Sample Size Used for the Test Set and Data Provenance:
The document provides limited details on the specific "test set" for the reported performance metrics.
- Comparative Study (Accuracy): The sample size for the comparative study between Sensi and Cardioscan is not explicitly stated in the provided text.
- CAA Algorithm (Specificity & Sensitivity): The sample size for the study reporting 94% specificity and 91% sensitivity for the "Design verification of a CAA algorithm" is not explicitly stated.
- Pediatric Murmur Study: "1568 heart sounds were accepted to meet the criteria of good quality and match the recorded pathological condition." This might represent a test set, but it's not explicitly labeled as such. The provenance of these heart sounds (country of origin, retrospective/prospective) is not specified.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications:
The document does not explicitly state the number or qualifications of experts used to establish the ground truth for any of the studies mentioned. The "1568 heart sounds" study mentions matching "the recorded pathological condition," implying expert diagnosis, but specifics are missing.
4. Adjudication Method for the Test Set:
The adjudication method (e.g., 2+1, 3+1, none) for establishing ground truth in any of the studies is not mentioned in the provided text.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done and Effect Size:
A multi-reader multi-case (MRMC) comparative effectiveness study was not mentioned or described in the provided text. The comparative study mentioned is between devices (Sensi vs. Cardioscan), not explicitly evaluating human reader performance with and without AI assistance. Therefore, there is no reported effect size regarding human reader improvement with AI assistance.
6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) was done:
The reported accuracy, specificity, and sensitivity figures (70.8% accuracy for Sensi vs. 67.9% for Cardioscan, and 94% specificity / 91% sensitivity for the CAA algorithm) appear to be standalone algorithm performance results. The device is described as a "decision support device" that "assists the medical examiner" and its interpretations are "only significant when used in conjunction with physician over-read." However, the reported performance metrics are presented for the device/algorithm itself.
7. The Type of Ground Truth Used:
The type of ground truth used is implied but not explicitly defined for all studies.
- For the comparative accuracy study and the CAA algorithm's specificity/sensitivity, the ground truth source is not explicitly stated. It can be inferred to be expert diagnosis or a "gold standard" for murmur classification, but no details are given.
- For the pediatric murmur study, it states "match the recorded pathological condition," suggesting that the ground truth was based on a recorded pathological diagnosis, presumably established by a medical professional.
8. The Sample Size for the Training Set:
The document does not provide any information regarding the sample size used for the training set of the Sensi's algorithms.
9. How the Ground Truth for the Training Set was Established:
The document does not provide any information on how the ground truth for the training set was established.
§ 870.1875 Stethoscope.
(a)
Manual stethoscope —(1)Identification. A manual stethoscope is a mechanical device used to project the sounds associated with the heart, arteries, and veins and other internal organs.(2)
Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 870.9.(b)
Electronic stethoscope —(1)Identification. An electronic stethoscope is an electrically amplified device used to project the sounds associated with the heart, arteries, and veins and other internal organs.(2)
Classification. Class II (special controls). The device, when it is a lung sound monitor, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 870.9.