The CMI Magnetocardiograph is intended for use as a tool that non-invasively measures and displays the magnetic signals produced by the electric currents in the heart.

Device Description

This device integrates an array of magnetic detectors with data acquisition hardware/software for the purpose of measuring the magnetic signals generated by the electrical current flowing in the heart. The detectors are housed in a vertically adjustable holder. The patient bed moves horizontally in orthogonal directions allowing the acquisition of multiple datasets for different locations above the torso. Three standard ECG electrodes are placed on each wrist and one ankle of the subject to provide a reference signal for synchronization of multiple MCG datasets.

The MCG data is preprocessed and displayed as either real time traces, averaged traces, or as multi-dimensional color maps.

AI/ML Overview

The CMI Magnetocardiograph's acceptance criteria and the study proving its compliance are detailed below. It's important to note that this 510(k) summary focuses on demonstrating substantial equivalence to predicate devices rather than establishing specific diagnostic performance metrics (e.g., sensitivity, specificity for a particular condition). Therefore, the "acceptance criteria" here relate to meeting the characteristics and safety standards of the predicate devices.

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria for the CMI Magnetocardiograph are implicitly derived from its comparison to the predicate devices: the Hewlett Packard ECG (K760542) and the Neuromag-122 magnetoencephalograph (K962764). The device's performance is demonstrated through its functional similarity and achieved safety standards.

Feature / Acceptance Criteria Category	CMI Magnetocardiograph Performance / Compliance
Functional Equivalence to ECG (K760542):
No. of detectors or channels	9 (less than predicate ECG, but compensated for by repositioning)
Detector type	SQUID - no contact to subject (differs from ECG electrodes but achieves non-invasive measurement)
Signal detected	Magnetic (differs from ECG's electrical but produces similar waveform morphology)
Waveform morphology	Similar to ECG waveforms (supported by data in Appendix H)
Coverage	Four acquisitions to cover entire heart (more complex than single ECG acquisition)
Patient position	Supine (consistent with ECG)
Functional Equivalence to MEG (K962764):
No. of SQUID detectors/channels	9 (36 effective via repositioning) (fewer than predicate MEG but compensated for repositioning)
Signal detected	Magnetic (consistent with MEG)
Operating Principle	Superconducting flux transformer coupled with DC-SQUID controlled by analog flux-locked loop (consistent with MEG)
Gradiometer	Second order (differs from MEG's planar-first order, but both are gradiometers)
Intersensor Spacing	40 mm (similar to MEG's 43-44 mm)
Magnetic field localization	Yes (consistent with MEG)
Cryogen Used	Liquid Helium (consistent with MEG)
Gantry	Floor mounted (consistent with MEG)
Coverage	Four acquisitions to cover entire heart (differs from MEG's one acquisition for entire head)
Patient position	Supine (differs from MEG's sitting or supine)
Magnetically shielded room	Not required (improves upon MEG which requires it)
Safety and Regulatory Compliance:
Fire, casualty, shock hazards	Complies with UL requirements for Class 1 equipment (UL # 51LB assigned)
Electromagnetic Compatibility	Compliance Certificate issued by Underwriters Laboratories
Software Performance	Tested in accordance with FDA guidelines (documented in Appendix C)
Lack of patient discomfort/pain	No instances in pilot study involving hundreds of subjects

2. Sample Size Used for the Test Set and Data Provenance

Sample Size: The document mentions a "pilot study involving hundreds of subjects" for safety assessment. For the substantial equivalence claims regarding waveform morphology (ECG comparison) and functional equivalence (MEG comparison), it states "[c]linical data was also used as part of the indication for substantial equivalence to 5-lead ECG (Appendix H)" and "Appendix H presents data to support this claim [equivalence to MEG]." However, the exact number of subjects for these specific comparative data sets (used for the "test set" in a traditional algorithm performance sense) and their precise breakdown are not provided in the excerpt.
Data Provenance: The document does not explicitly state the country of origin. It indicates "Extensive on-site testing at clinical sites" and "Data, taken from human subjects," which implies prospective collection at those clinical sites. It does not specify whether the data was retrospective or prospective beyond the implication of "clinical sites" and "hundreds of subjects" in a pilot study.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

The document does not provide information on the number or qualifications of experts used to establish a "ground truth" for the test set in the context of diagnostic performance (e.g., identifying specific heart conditions). The primary "ground truth" for this 510(k) is the established and accepted performance and safety of the predicate devices. The study aims to show the CMI Magnetocardiograph produces similar waveforms to an ECG and uses similar technology to an MEG.

4. Adjudication Method for the Test Set

The document does not describe an adjudication method for a test set in the context of diagnostic performance. The evaluation is based on comparing device characteristics and observed waveforms.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and Effect Size of Human Reader Improvement

No. The document does not describe a MRMC comparative effectiveness study, nor does it discuss human reader improvement with or without AI assistance. This submission focuses on the standalone device performing similar to predicate devices, not on human-AI interaction or diagnostic aid.

6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Was Done

Yes. The entire submission describes the performance of the device in a standalone capacity. It measures and displays magnetic signals. There is no mention of a human-in-the-loop component for its primary function in this submission relevant to its substantial equivalence claim. The device is a "tool which non-invasively measures and displays the magnetic signals produced by the electric currents in the heart."

7. The Type of Ground Truth Used

The "ground truth" for this 510(k) submission is primarily:

Functional Characteristics and Safety of Predicate Devices: The CMI Magnetocardiograph is judged against the established characteristics, safety profiles, and intended uses of the Hewlett Packard ECG and the Neuromag-122 MEG.
Expert Consensus on Waveform Morphology: For the ECG comparison, the "basis for equivalence...is that the CMI Magnetocardiograph produces magnetic waveforms (or traces) very similar in morphology to the electrical waveforms produced by the 5-lead Electrocardiograph." This implies an expert assessment or comparison of the visual similarity of these waveforms, though no specific expert panel is detailed.
Engineering and Physics Principles: For the MEG comparison, the "basis for equivalence...is that the Magnetoencephalograph (MEG) predicate and the magnetocardiograph (MCG) both use very similar technology (SQUIDS) and both measure the magnetic field emanating from a source - they are functionally equivalent." This relies on established engineering principles and the known functionality of SQUID technology.

8. The Sample Size for the Training Set

The document does not mention a "training set" in the context of machine learning. The device described appears to be a hardware-based measurement system, not an AI/ML algorithm that undergoes a distinct training phase. Its software is tested for compliance, but not "trained" in the ML sense.

9. How the Ground Truth for the Training Set Was Established

As there is no explicit training set described for an AI/ML algorithm, this question is not applicable based on the provided document. The device's "training" in a broad sense would be its design, calibration, and engineering to measure physical phenomena accurately.

Summary

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033488

JUL - 7 2004

510(k) Summary for CMI Magnetocardiograph

SPONSOR 1.

CardioMag Imaging, Inc. 450 Duane Avenue, Schenectady, New York 12304

Contact Person: Steve Karr, Ph.D. 518 381 1000, ext.37 e-mail: skarr(@cardiomag.com Telephone:

Date Prepared: June 29, 2004

2. Device Name

CMI Magnetocardiograph Proprietary Name: Common/Usual Name: magnetocardiograph Classification Name: to be determined

3. PREDICATE DEVICES

Hewlett Packard, model 1511B	ECG	K760542
Neuromag-122	magnetoencephalograph	K962764

4. DEVICE DESCRIPTION

The MCG data is preprocessed and displayed as either real time traces, averaged traces, or as multi-dimensional color maps.

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5. INTENDED USE

The CMI Magnetocardiograph is intended for use as tool which non-invasively measures and displays the magnetic signals produced by the electric currents in the heart.

Technological Characteristics and Substantial Equivalence 6.

The CMI Magnetocardiograph is substantially equivalent to the Hewlett Packard ECG [510(k) number K760542] and the Neuromag Ltd. Magnetoencephalograph (MEG) called the Neuromag-122 [510(k) number K962764] in safety and effectiveness. Two tables, H.1 and H.2, are presented to illustrate the similarities and differences between the CMI Magnetocardiograph and its predicates.

Parameter	CMI Magnetocardiograph	Hewlett Packard ECG
No. of detectors or channels	9	5
Detector (or Sensor)	SQUID - no contact to subject	Electrode - contacts subject
Signal detected non-invasively	magnetic	Electrical
Waveform morphology	Similar to ECG
Coverage	Four acquisitions to coverentire heart	One acquisition
Patient position	Supine	Supine or standing

Comparison Tables

Table	H.2
-------	-----

Parameter	CMI Magnetocardiograph	Neuromag-122 MEG
No. of SQUIDdetectors/channels	9 (36 effective via re-positioning)	122
Signal detected	magnetic	Magnetic
Operating Principle	Superconducting fluxtransformer coupled withDC-SQUID controlled byanalog flux-locked loop	Superconducting fluxtransformer coupled withDC-SQUID controlled byanalog flux-locked loop
Gradiometer	Second order	Two orthogonal planar-firstorder gradiometers perlocation
Intersensor Spacing	40 mm	43-44 mm
Magnetic field localization	Yes	Yes
Cryogen Used	Liquid Helium	Liquid Helium
Gantry	Floor mounted	Floor mounted
Coverage	Four acquisitions to cover	One acquisition to cover

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	entire heart	entire head
Patient position	Supine	Sitting or supine
Magnetically shielded room	Not required	Required

The basis for equivalence to the 5-lead Electrocardiograph predicate is that the CMI Magnetocardiograph produces magnetic waveforms (or traces) very similar in morphology to the electrical waveforms produced by the 5-lead Electrocardiograph, both waveforms emanating from the human heart. Data, taken from human subjects, is presented in Appendix H (Substantial Equivalence Information) to support this claim.

The basis for equivalence to the Magnetoencephalograph is that the Magnetoencephalograph (MEG) predicate and the magnetocardiograph (MCG) both use very similar technology (SQUIDs) and both measure the magnetic field emanating from a source - they are functionally equivalent. Appendix H presents data to support this claim.

Safety

The CMI Magnetocardiograph uses liquid Helium cooled sensors, which are housed in a thermally insulated cryostat, the outside temperature of which is at ambient temperature. In the highly unlikely event of the accidental rapid evaporation of the cryogen, the flow of gas would be upward, away from the subject. Refill of the cryostat is easily accomplished following the instructions and illustrations in the hardware manual. Since the device is entirely passive, does not touch the subject, and is housed in an electrically neutral fiberglass housing, the system is at least as safe as electrical ECG systems for both the operator and the subject. Comparable to the Neuromag-122 MEG system, the sensors make no contact to the subject. During a pilot study involving hundreds of subjects, there are no instances of any discomfort or pain to the patient, nor have any safety issues arisen while obtaining cardiac data from a subject.

7. PERFORMANCE TESTING

The device was tested by the Underwriters Laboratories and found to comply with requirements for fire, casualty and shock hazards covering UL equipment Class 1, and judged to be eligible for Classification and Follow-Up Service. The result is that CardioMag Imaging, Inc. (CMI) is authorized to use the UL marking, and is assigned UL # 51LB. Underwriters Laboratories also conducted Electromagnetic Compatibility Testing, the result being a Compliance Certificate given to CMI. Details can be found in Appendix D.

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Extensive on-site testing at clinical sites shows that the device performs to specifications in a clinical environment. Clinical data was also used as part of the indication for substantial equivalence to 5-lead ECG (Appendix H).

Bench tests are applied to all units which leave CMI to be used for R&D investigations. Results of the bench testing are reviewed to assess pass or failure of the components and the system.

Each new version of the software is tested in accordance with FDA guidelines. Results of performance testing for the latest version of the software are documented in Appendix C.

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Image /page/4/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a stylized caduceus symbol, which is a staff with two snakes coiled around it, enclosed within a circle. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" is written around the perimeter of the circle.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

JUL - 7 2004

CardioMag Imaging, Inc. c/o Steve Karr, Ph.D. Program Manager 450 Duane Avenue Schenectady, NY 12304

Re: K033488

Trade Name: CMI Magnetocardiograph, Model 2409 Regulation Number: 21 CFR 870.2340 Regulation Name: Electrocardiograph Regulatory Class: Class II (two) Product Code: 74 DPS Dated: April 9, 2004 Received: April 12, 2004

Dear Dr. Karr:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate for associated in to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA). it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21

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Page 2 - Steve Karr, Ph.D.

CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050. This letter will allow you to begin marketing your device as described in your Section 510(k) I mis lotter will and my Jourse of substantial equivalence of your device to a legally premated predicated device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please contact the Office of Compliance at (301) 594-4648. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). You may obtain other general information on your responsibilities under the Act from the Division of Small other general international and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html

Sincerely yours,

Bram D. Zuckerman, M.D.

Director Division of Cardiovascular Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Indications for Use

KO33488 510(k) Number (if known):

Device Name:_CMI 2409 Magnetocardiograph

Indications For Use:

The CMI Magnetocardiograph is intended for use as a tool that non-invasively measures and displays the magnetic signals produced by the electric currents in the heart.

Prescription Use X (Part 21 CFR 801 Subpart D) AND/OR

Cver-The-Counter Use (21 CFR 801 Subpart C)

(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

(Division Sign-Off)
Division of Cardiovascular Devices
510(k) Number K03348...

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Regulation Number and Section

§ 870.2340 Electrocardiograph.

(a)
Identification. An electrocardiograph is a device used to process the electrical signal transmitted through two or more electrocardiograph electrodes and to produce a visual display of the electrical signal produced by the heart.(b)
Classification. Class II (performance standards).