K202527 · iRhythm Technologies, Inc. · DQK · May 21, 2021 · Cardiovascular
Device Facts
Record ID
K202527
Device Name
Zio ECG Utilization Software (ZEUS) System
Applicant
iRhythm Technologies, Inc.
Product Code
DQK · Cardiovascular
Decision Date
May 21, 2021
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 870.1425
Device Class
Class 2
Attributes
AI/ML, Software as a Medical Device
AI Performance
Output
Algorithm
Acceptance
Observed
Dev DS
Dev Readers
Test DS
Test Readers
Arrhythmia detection
ECGDL
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ECG segment detection
ECGDL
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Indications for Use
The device is intended to capture, analyze and report symptomatic and asymptomatic cardiac events and continuous electrocardiogram information for long-term monitoring. After wear, ECG data from compatible monitoring devices is processed and analyzed by the ZEUS System. A final report is generated on the beat-to-beat information from the entire ECG recording. For the Zio AT service, the ZEUS System supports the capture and analysis of automatically-detected arrhythmia events, as well as the analysis of uploaded patient-triggered events. The ZEUS System is indicated for use on patients 18 years or older who may be asymptomatic or who may suffer from transient symptoms such as palpitations, shortness of breath, dizziness, light-headedness, pre-syncope, syncope, fatigue, or anxiety and patients who are asymptomatic. The reports are provided for review by the intended user to render a diagnosis based on clinical judgment and experience. It is not intended for use on critical care patients.
Device Story
ZEUS System is a software-based platform for analyzing ECG data from compatible wearable monitors (Zio XT, Zio AT, Zio Monitor). It processes continuous ECG recordings to identify beats, ectopic runs, rhythms, heart rate, and ECG segments (QT). The system uses an automated ECG analysis platform to generate preliminary findings; these are reviewed by Certified Cardiographic Technicians (CCTs) before a final report is published to a secure website for clinician review. For Zio AT, the system supports real-time automated arrhythmia detection and transmission of patient-triggered events. Clinicians use the final report to aid in arrhythmia diagnosis and management. The system operates in a professional clinical context; it is not for patient self-diagnosis or critical care environments.
Clinical Evidence
No clinical testing was performed. Substantial equivalence was supported by nonclinical verification, system-level regression testing, and conformance to FDA-recognized consensus standards (AAMI ANSI ISO 14971, IEC 62304, AAMI ANSI IEC 60601-2-47, AAMI ANSI EC57).
Technological Characteristics
Software-based diagnostic system for ECG analysis. Features include automated rhythm detection and QT segment measurement. Connectivity via secure website for clinician access. Complies with IEC 62304 (software lifecycle), AAMI ANSI IEC 60601-2-47 (ambulatory ECG systems), and AAMI ANSI EC57 (rhythm/ST measurement algorithms).
Indications for Use
Indicated for patients 18+ years, symptomatic (palpitations, dyspnea, dizziness, light-headedness, pre-syncope, syncope, fatigue, anxiety) or asymptomatic, requiring long-term ECG monitoring. Not for critical care patients.
Regulatory Classification
Identification
A programmable diagnostic computer is a device that can be programmed to compute various physiologic or blood flow parameters based on the output from one or more electrodes, transducers, or measuring devices; this device includes any associated commercially supplied programs.
Predicate Devices
Zio® ECG Utilization Software (ZEUS) System (K190593)
Submission Summary (Full Text)
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May 21, 2021
iRhythm Technologies, Inc. Rev Jacinto Sr. Manager, Regulatory Affairs 699 8th Street San Francisco, California 94103
Re: K202527
Trade/Device Name: Zio ECG Utilization Software (ZEUS) System Regulation Number: 21 CFR 870.1425 Regulation Name: Programmable Diagnostic Computer Regulatory Class: Class II Product Code: DQK, DSI, DSI, DXH Dated: August 31, 2020 Received: September 1, 2020
Dear Rey Jacinto:
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 commerce prior 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. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to 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
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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 CFR Part 807); labeling (21 CFR Part 801); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.
For comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely,
Jennifer Shih Kozen Assistant Director Division of Cardiac Electrophysiology, Diagnostics and Monitoring Devices Office of Cardiovascular Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health
Enclosure
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# Indications for Use
510(k) Number (if known) K202527
Device Name Zio® ECG Utilization Service (ZEUS) System
### Indications for Use (Describe)
The device is intended to capture, and report symptomatic and asymptomatic cardiac events and continuous electrocardiogram information for long-term monitoring. After wear, ECG data from compatible monitoring devices is processed and analyzed by the ZEUS System. A final report is generated on the beat-to-beat information from the entire ECG recording. For the Zio AT service, the ZEUS System supports the capture and analysis of automatically-detected arrhythmia event, as well as the analysis of uploaded patient-triggered events.
The ZEUS System is indicated for use on patients 18 years or older who may be asymptomatic or who may suffer from transient symptoms such as palpitations, shortness of breath, dizziness, light-headedness, pre-syncope, fatigue, or anxiety and patients who are asymptomatic. The reports are provided for review by the intended user to render a diagnosis based on clinical judgment and experience. It is not intended for use on critical care patients.
| Type of Use (Select one or both, as applicable) |
|-------------------------------------------------|
|-------------------------------------------------|
X Prescription Use (Part 21 CFR 801 Subpart D)
| Over-The-Counter Use (21 CFR 801 Subpart C)
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## 510(k) Notification K202527
#### l. General Information
### Applicant:
iRhythm Technologies, Inc.
699 8th Street, Suite 600
San Francisco, CA 94103 USA
Phone: 415-632-5700
Fax: 415-632-5701
### Contact Person:
Rey Jacinto Sr. Manager, Regulatory Affairs Phone: 415-214-7440 Email: rey.jacinto@irhythmtech.com Date Prepared: August 31, 2020
#### II. Device Information
Trade Name:
ZEUS System
### Generic/Common Name:
Programmable diagnostic computer
### Classification Names:
Programmable diagnostic computer [21CFR§870.1425]
Arrhythmia detector and alarm (including ST-segment measurement and alarm)[21CFR§870.1025]
Telephone electrographic transmitter and receiver [21CFR§870.2029]
## Regulatory Class:
Class II (Special controls)
### Product Codes:
DQK, Computer, Diagnostic, Programmable
DSI, Detector and Alarm, Arrhythmia
DXH, Transmitters and Receivers, Electrocardiographic, Telephone
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#### III. Predicate Devices
The following predicate device has been selected:
- iRhythm Technologies, Inc. Zio® ECG Utilization Software (ZEUS) System [K190593]
#### IV. Indications for Use
The Indications for Use statement for the ZEUS System is as follows:
The device is intended to capture, analyze and report symptomatic and asymptomatic cardiac events and continuous electrocardiogram information for long-term monitoring. After wear, ECG data from compatible monitoring devices is processed and analyzed by the ZEUS System. A final report is generated on the beat-to-beat information from the entire ECG recording. For the Zio AT service, the ZEUS System supports the capture and analysis of automatically-detected arrhythmia events, as well as the analysis of uploaded patient-triggered events.
The ZEUS System is indicated for use on patients 18 years or older who may be asymptomatic or who may suffer from transient symptoms such as palpitations, shortness of breath, dizziness, light-headedness, pre-syncope, syncope, fatigue, or anxiety and patients who are asymptomatic. The reports are provided for review by the intended user to render a diagnosis based on clinical judgment and experience. It is not intended for use on critical care patients.
#### V. Device Description
The Zio® Service consists of single-patient-use monitoring devices and the Zio ECG Utilization Software (ZEUS) System, the subject device of this submission, for analysis and reporting of cardiac information derived from ECG data. The ZEUS System is a software system consisting of a collection of software modules designed to store and analyze data from compatible cardiac monitoring devices to curate a report of preliminary findings intended for use by clinicians as an aid in arrhythmia diagnosis and management. The ECG Analysis Software of the ZEUS System is used by Certified Cardiographic Technicians (CCTs) prior to publishing the reported cardiac information in the Final Report and is not utilized directly by the prescribing clinician or patient. The reported cardiac information includes beats, ectopic runs, ECG segments, rhythms, and heart rate measurements. Recorded ECG is processed by an automated ECG analysis platform; results are quality reviewed by CCTs, findings and associated ECG are captured in a report provided to clinicians via a secure website. For the Zio® AT Patch/Gateway, the ZEUS System provides capabilities to automatically detect clinically actionable arrhythmia during the monitoring period, as well as receive baseline, scheduled, symptomatic and asymptomatic transmissions.
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#### VI. Comparison of Technological Characteristics with Predicate Devices (Substantial Equivalence)
The proposed indications for use statement for the ZEUS System are identical to the indications for use in the predicate device. The differences in the technological characteristics, namely the introduction of ECG segment detection, between the devices are substantially equivalent as the fundamental scientific technology and intended use is unchanged. Thus, the ZEUS System is considered substantially equivalent to the predicate device.
A comparison table outlining the differences and similarities between the subject device and the predicate device is provided in Table 1.
| Feature | Subject Device:<br>ZEUS System<br>(K202527) | Predicate Device:<br>ZEUS System<br>(K190593) |
|----------------------------------------------|------------------------------------------------|--------------------------------------------------------------------------------|
| General Characteristics | | |
| Classification | Same | Class II (Special controls)<br>21CFR870.1425<br>21CFR870.1025<br>21CFR870.2029 |
| Product Code | Same | DQK<br>DSI<br>DXH |
| Patient Environment | Same | Ambulatory |
| Patient Population | Same | Non-pediatric, non-critical<br>care patients |
| Technological Characteristics | | |
| Data Input | Same | Digital long-term<br>continuous ECG |
| Data Download | Same | Yes |
| Data Storage | Same | Yes |
| Rhythm Detection<br>Algorithm + ECG Analysis | ECGDL | ECGML + ECGDL |
| ECG Segments | QT | N/A |
| Interoperability | Zio® XT Patch<br>Zio® AT Patch<br>Zio® Monitor | Zio XT Patch<br>Zio AT Patch |
Table 1. Substantial Equivalence Summary Table
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#### VII. Performance Data
Safety and performance of the ZEUS System has been evaluated and verified in accordance with design specifications and to support a determination of substantial equivalence to the predicate device.
Nonclinical testing summarized in Table 2 demonstrates that the ZEUS System is in conformance with FDA-recognized consensus standards and FDA guidance documents.
| FDA # | Body | Number/Version | Title |
|-------|---------------|---------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| 5-40 | AAMI ANSI ISO | 14971:2012(R)2010<br>(Corrected 4<br>October 2017) | Medical Devices – Application of risk<br>management to medical devices |
| 13-79 | IEC | 62304 Edition 1.1<br>2015-06<br>CONSOLIDATED<br>VERSION | Medical device software - Software<br>life cycle processes |
| 3-127 | AAMI ANSI IEC | 60601-2-47:2012 | Medical Electrical Equipment -- Part<br>2-47: Particular Requirements For<br>The Basic Safety And Essential<br>Performance Of Ambulatory<br>Electrocardiographic Systems |
| 3-118 | AAMI ANSI | EC57:2012 | Testing and reporting performance<br>results of cardiac rhythm and ST<br>segment measurement algorithms |
| N/A | U.S. FDA | October 2, 2014 | Guidance for Industry and FDA Staff –<br>Content of Premarket Submissions<br>for Management of Cybersecurity in<br>Medical Devices |
| N/A | U.S. FDA | May 5, 2005 | Guidance for the Content of<br>Premarket Submissions for Software<br>Contained in Medical Devices |
Table 2. FDA-Recognized Consensus Standards & Guidance Document Summary
The nonclinical verification and performance test results established that the device meets its design requirements and intended use, that the modifications to the cleared device are as safe and effective as the predicate. During the development, potential hazards were evaluated and controlled by the risk management activities, including risk analysis, risk mitigation, verification and benefit-risk analysis. The verification and system-level regression testing demonstrate that the device meets all its specifications.
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#### VIII. Clinical Testing in Support of Substantial Equivalence Determination
No clinical testing was performed in support of this premarket notification.
#### IX. Conclusion
The results confirm by examination and provision of objective evidence that the design output met the design input requirements. The results of the nonclinical testing performed demonstrate that the ZEUS System meets the requirements of established conformance standards and performance specifications necessary for its intended use and does not raise new questions of safety or effectiveness as compared to the predicate device. The ZEUS System is substantially equivalent to the predicate device.
Two short videos show you everything — or skip straight to the written tutorial if you'd rather read. You can reopen this any time from the Tutorial button in the top bar.
Part 1 — Search, results, and everyday workflows 16 min
Part 2 — Embeddings: the galaxy map 3 min
1. Search: exact and fuzzy
Type a phrase like "coronary artery calcification" into the search box. You get two kinds of results. Exact results match the literal phrase — prefix searches work ("coronary artery calcificati") but suffix searches do not. Fuzzy results match on the meaning and intent of your phrase rather than the exact words, and are sorted by relevance score. Hover over the Exact or Fuzzy badge on any row to see exactly why it matched.
Use the checkboxes above the results to narrow: SaMD keeps only software-only devices, AI / ML keeps only devices with AI.
Exact vs. fuzzy search: what's the difference?
Exact matches on the literal phrase (prefix search works, suffix does not). Fuzzy matches on the meaning and intent of the phrase rather than the exact words. Hover over the badge on any row to see why it matched.
You search "coronary artery calcification" and want only software devices with AI. What two filters do you apply?
Narrow by SaMD (software-only devices), then narrow by AI/ML (devices with AI).
2. The results table
Scroll right in the results table. The intended use is extracted for you — no need to open the PDF. The device story gives a high-level snapshot of what the device does and how it's used. The AI Performance sub-table shows each output name, acceptance criteria, observed values, and development/test dataset descriptions — the same format Innolitics uses for regulatory strategy outputs, and the fastest high-level fingerprint of an AI device. It is AI-generated but has been very reliable in practice.
Where do you find a device's intended use without opening the PDF?
Scroll right in the search results table. The intended use column is extracted for you; no need to dig into the 510(k) summary PDF.
What does the AI Performance sub-table show, and why is it useful?
Output name, acceptance criteria, observed values, development dataset description, and test dataset description. It's the same format we use for regulatory strategy output and Fast 510(k) input, and the fastest high-level fingerprint of an AI device. AI-generated but reliable in practice.
3. Judging fuzzy relevance
Fuzzy results trail off in relevance as you scroll. Use three signals to decide how far down to go: the fuzzy badge explanations, the intended use column, and whether your target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, you're past the relevant zone. A top hit with a low score (~0.4) and a stretched explanation is a hint the closest predicates are far away — the project may be headed for De Novo. Note the fuzzy search is a pattern match: it doesn't handle negation ("not") well, and hardware devices can appear — filter by SaMD/AI ML to cut them.
How do you judge how far down fuzzy search results to go?
Use the relevancy signals: the fuzzy badge explanations, the intended use column, and whether the target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, results are trailing off in relevancy.
4. Device detail page: chat and citations
Click a device name to open its detail page: device facts on the left, a chat window on the right. Ask something like "Describe the training data". The answer carries little citation bubbles — click one to jump to the highlighted passage in the source PDF, so you can verify every AI answer against the document. There's also a Download PDF button for sharing.
How do you verify an AI chat answer on the device detail page?
Click the citation bubbles to jump to the relevant highlight in the source document.
Reading rule for every project: how many summaries do you read in full?
At least the three most relevant 510(k) or De Novo summaries, in full. After that, use targeted chat questions to confirm your memory quickly. The tool supports this professional habit — it doesn't replace it.
5. Side-by-side comparison
Select multiple rows in the results table (aim for under ~10), then open the PDF Viewer tab. Ask one question — it goes to all selected devices in parallel, each with citations. This is the fastest way to compare and contrast devices: training data, PCCP scope, how they handled adding new scanners, and so on.
What does the side-by-side PDF viewer mode do?
Select multiple devices, open the PDF viewer tab, and ask one question (e.g., "Describe the training data"). It queries all selected devices simultaneously with citations, so you can compare and contrast quickly.
6. Collections
With rows selected, go to the Collections tab and create a labeled collection (e.g., "Cobb Angle Project"). Reload that selection any time — before a client call, pull up the collection and ask questions across all of its devices at once.
How do you save a set of selected devices for later use?
Select the rows, go to the Collections tab, and create a labeled collection (e.g., "Cobb Angle Project"). You can reload the selection anytime and carry it into the PDF viewer and other tabs that support selections.
7. Product codes and the regulations tree
Click a product code in the results to jump to it in the regulations tree — identification text, sibling product codes, and devices you can open in a PDF viewer on the right. Click a regulation number to see its identification, special controls, and related product codes. You can also search by product code or regulation number at the top of the tree. Always read the special controls if any exist for your device — it broadens your search and sharpens pre-kickoff research.
What can you do from the regulations tree view?
Browse product codes and regulation numbers, read the identification text and special controls, browse sibling product codes, open device PDFs on the right, and search by product code or regulation number at the top of the tree.
8. Chart view
Click Show Chart and segment by regulation number (or product code) to see which regulations dominate your result set. Clicking a regulation takes you into the regulations tree. Great for spotting that most matches are, say, hardware laparoscopic devices — a cue to go back and filter.
How do you see which regulations dominate a search result set?
Click "Show Chart" and segment by Regulation Number. Clicking a regulation takes you to the regulations tree.
9. The predicate graph
Open the Predicates tab for a family-tree view of predicate relationships. Click a node to trace its parents and children; selections from search carry over pre-selected. Commonly predicated devices are worth reading — a lot of people predicated them for a reason. The visual lineage is also handy on client calls, e.g. to show how a predicate family evolved and justify why your predicate still holds.
In the predicate graph, why are commonly predicated devices worth reading?
A lot of people predicated them for a reason. Clicking a node traces parents and children, and selections from search carry over pre-selected.
10. Embeddings: the galaxy map
The Embeddings tab plots every matching document in a 2-D "galaxy map" where semantically similar devices cluster together. Hover or click clusters to explore, and let AI label the clusters for you. Embeddings beat product codes for grouping: two devices can carry different product codes (LLZ vs. QIH) yet do the same thing — the embedding captures the meaning of the intended use and device story. This is also exactly how retrieval-augmented generation (RAG) works under the hood, and it makes a great visual on client calls.
Try it yourself
Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.