K970072 · Ela Medical, Inc. · DXY · Aug 29, 1997 · Cardiovascular
Device Facts
Record ID
K970072
Device Name
OPUS S MODEL 4121 AND 4124 PACEMAKERS
Applicant
Ela Medical, Inc.
Product Code
DXY · Cardiovascular
Decision Date
Aug 29, 1997
Decision
ST
Submission Type
Traditional
Regulation
21 CFR 870.3610
Device Class
Class 3
Attributes
Therapeutic
Indications for Use
Generally accepted indications for long-term single-chamber cardiac pacing include: - AV conduction disorders or intraventricular paroxysmal/permanent conduction disorders with permanent atrial tachycardia: atrial fibrillation or flutter (lead implanted in the ventricle), - Sinus bradycardia, sinoatrial block, brady-tachy syndrome without atrioventricular conduction disorder (lead implanted in the atrium).
Device Story
Opus S Models 4121/4124 are single-chamber programmable pacemakers; provide cardiac pacing therapy. Device monitors intrinsic cardiac activity via implanted leads; delivers electrical pulses to heart based on programmed parameters (rate, amplitude, width, sensitivity). Operated by physicians using external programmer system (programming head, software, PC). Provides diagnostic data including event markers, intracardiac ECG, and lead measurements (impedance, current, voltage, energy). Output assists clinicians in managing patient pacing needs; improves patient comfort via smaller form factor compared to predicates. Used in clinical settings for long-term management of bradyarrhythmias.
Clinical Evidence
Bench testing only. Testing included sterilization validation, mechanical/environmental performance (thermal shock, vibration, drop tests), connector testing, feedthrough testing, hybrid component testing, and electromagnetic interference protection. Software validation for implant and programmer software was performed. No clinical data provided.
Technological Characteristics
Single-chamber pacemaker; titanium hermetic case; silicone elastomer connector. Hybrid circuit substrate with microprocessor and custom integrated circuits. Programmable SSI, SST, SOO modes. Unipolar (4121) or Unipolar/Bipolar (4124) sensing/pacing. Battery: WG 8426. Connectivity via external programmer system. Sterilization: ETO.
Indications for Use
Indicated for patients with AV conduction disorders, intraventricular conduction disorders with permanent atrial tachycardia (atrial fibrillation/flutter), sinus bradycardia, sinoatrial block, or brady-tachy syndrome without AV conduction disorder.
Regulatory Classification
Identification
An implantable pacemaker pulse generator is a device that has a power supply and electronic circuits that produce a periodic electrical pulse to stimulate the heart. This device is used as a substitute for the heart's intrinsic pacing system to correct both intermittent and continuous cardiac rhythm disorders. This device may include triggered, inhibited, and asynchronous modes and is implanted in the human body.
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k970073
AUG 29 1997
## Summary & Certification
### Summary of safety and effectiveness information
#### General Information
**Device Generic Name:** Single chamber, SSI pacemaker.
**Device Trade Name:** Opus S Model 4121 and 4124 pacemakers
**Applicant’s Name and Address:** ELA Medical, Inc., 2950 Xenium Lane N., Suite 120, Plymouth, MN 55441, Tel. (612) 519-9400
**Date of Summary Preparation:** October 21st, 1996
**Contact Person:** Catherine G. Goble
**510(k) Number:** K970072
**Date of Judgment of Substantial Equivalence Sent to Applicant:**
**Predicate Devices:** ELA Medical Opus Model 4021 (510(k) K900461 and K952363, ELA Medical Inc.) and 4024 pacemakers (510(k) K882391 and K952364, ELA Medical Inc.).
#### Description of Conditions for Which the Devices are Indicated
Generally accepted indications for long-term single-chamber cardiac pacing include:
- AV conduction disorders or intraventricular paroxysmal/permanent conduction disorders with permanent atrial tachycardia: atrial fibrillation or flutter (lead implanted in the ventricle),
- Sinus bradycardia, sinoatrial block, brady-tachy syndrome without atrioventricular conduction disorder (lead implanted in the atrium).
#### Device Description
Opus S, Model 4121 and 4124 are single-chamber programmable pacemakers with the following specifications:
**Programmable parameters:**
**Basic parameters:**
Mode: SSI, SST, SOO
Basic rate (ppm): 30, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 89, 96
Maximum rate (ppm): 101, 110, 120, 132, 142, 154
Hysteresis (% of rate): 0, 5, 10, 20, 33
Absolute refractory period (ms): 172, 203, 234, 266, 297, 328, 359
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Pacing and sensing:
Pulse amplitude (V): 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 5.0,
Pulse width (ms): 0.12, 0.24, 0.37, 0.49, 0.61, 0.73, 0.85, 98
Sensitivity (mV): 0.4, 0.6, 0.8, 1.0, 1.2, 1.5, 1.8, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5
Polarity:
| | Model 4121 | Model 4124 |
| --- | --- | --- |
| Pacing | Unipolar | Unipolar - Bipolar |
| Sensing | Unipolar | Unipolar - Bipolar |
Specific function:
Rate-smoothing (ms/8 cycles): 16, 31, 47, 63, 78, 94, OFF
Non-programmable parameters
Rate limit: 170 ppm
Magnet rate: 96 ppm at BOL, 80 ppm at ERI
Technical specifications
| | Model 4121 | Model 4124 |
| --- | --- | --- |
| Dimensions (mm) | 52.4 x 36.1 x 6.6 | 47.6 x 36.1 x 6.6 |
| Weight (g) | 25 | 25 |
| Volume (cc) | 9.9 | 9.4 |
| Connections | Unipolar, 5.0-6.0 mm | Unipolar/bipolar, IS-1 3.2 mm |
| Battery | WG 8426, 0.94 Ah | WG 8426, 0.94 Ah |
| Longevity | 6 years* | 6 years* |
* 100 % pacing, SSI, 70 ppm, 3.5 V, 0.49 ms, 500 Ω, 37 °C
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# Follow-up functions
## Statistics:
Number and percentage of: paced cycles, sensed cycles, extrasystoles
Number of: cardiac cycles, programmings
**Heart rate curve:** 45 minutes, 24 hours, **OFF**
**Event markers:** Identification of two event types: spontaneous and paced events
**Intracardiac ECG**
**Threshold test:** Programmable threshold test rate (ppm): 80, 89, **101**, 110, 120
**Lead measurement:** Impedance, current, voltage, and energy
**As shipped values shown in bold/italics**
## Physical characteristics
The electronic circuit and battery of Opus S Model 4121 and 4124 pacemakers are encapsulated in a hermetic titanium case. Pacing leads are connected through a medical grade silicone elastomer connector. The different functions of Opus S Model 4121 and 4124 pacemakers are assured by a hybrid circuit. The hybrid circuit is a substrate onto which different electronic components are mounted:
- passive components (resistors, capacitors, etc.) and
- integrated circuits (microprocessor and custom circuit).
## Programmer system
The programmer system consists of:
- Programming head
- Programmer software
- IBM-compatible PC
Opus S Model 4121 and 4124 pacemakers are similar in design and construction to other single-chamber pacemakers in commercial distribution.
## Comparison to predicate devices
ELA Medical Opus™ S Model 4121 and 4124 pacemakers are similar to the predicate Opus™ Model 4021 and 4024 pacemakers, respectively, except for these general differences. Physically, both Opus-S models are smaller to improve patient comfort. A smaller size was achieved by using a smaller (but widely used) battery, reducing the
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connector size (without substantially altering its design) and making the hybrid smaller. Functionally, a few programmable parameter values were changed to make Opus S more flexible for managing patient conditions. Pacing and sensing polarity were also made independently programmable for Opus-S Model 4124 pacemaker (versus fixed for Opus models) to offer more flexibility to manage patient needs. Otherwise, the two Opus-S models are substantially equivalent to the two respective predicate Opus models. The programmer parameter value changes and programmable polarity were achieved by modifying the custom integrated circuit on the hybrid. The programmer system is similar to that of Opus™ Model 4021 and 4024.
Similar designs and manufacturing processes, and the same materials, are used to make the ELA Medical Model 4121, 4124, 4021 and 4024 pacemakers.
## Alternatives
The alternatives for Opus S Model 4121 and 4124 pacemakers are other commercially available single-chamber, SSI pacemakers.
## Marketing History
Opus S Model 4121 and 4124 pacemakers are not in commercial distribution in the U.S. They were recently introduced into commercial distribution outside the U.S. No unanticipated adverse device effects have been reported for these pacemakers.
## Potential Adverse Effects
The potential adverse effects of Opus S Model 4121 and 4124 pacemakers are the same as those for single-chamber (SSI) pacemakers in commercial distribution. Pacemaker-related complications are described in the Opus S physician's manual.
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# Summary of Studies
The following in-vitro functional testing was performed on the Opus S Model 4121 and 4124 pacemakers:
| Test group | Tests |
| --- | --- |
| Sterilization Process Validation | • ETO sterilization process validation
• Mechanical qualification of sterilization process modification
• Sterilization indicator qualification |
| Laser Welding Process Validation | |
| Pacemaker Environmental Performance Testing | • Baseline Electrical Performance
• Thermal Shock
• Mechanical Shock
• Random Vibration
• Vibration: Italian Requirements
• Drop Tests (packaged and unpackaged devices) |
| Connector Testing (IS-1 and 5.0-6.0 mm) | • Electrical Isolation
• Pacing Lead Insertion/Withdrawal Forces
• Electrical Resistance
• Rotation of Inserts
• Perforation and Rupture Force |
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| Test group | Tests |
| --- | --- |
| Feedthrough Testing | - Electrical Isolation Resistance
- Hermeticity
- Tensile Strength
- Temperature Cycling
- Aging |
| Mechanical Qualification of Packaging | - Bioburden
- Visual Inspection
- Hermeticity |
| Hybrid Testing | - Environmental
- Temperature Cycling
- Constant Acceleration
- Vibration
- Mechanical Shock
- Seal Hermeticity
- Particle Impact Noise Detection (PIND)
- Final Electrical Test
- Life (Reliability) Test |
| Die Attach Qualification | |
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| Test group | Tests |
| --- | --- |
| Hybrid Component Testing | - Microprocessor
- Ceramic and Tantalum capacitors
- Resistor chip
- Zener diode
- Pacing chip |
| Pacemaker Interference Testing | - Protection Against Spurious Current Induced by Electromagnetic Interference
- Protection Against Sensing Electromagnetic Interference
- Protection Against Malfunction Due to Electromagnetic Interference
- Protection Against Electrosurgery Current
- Defibrillation Protection
- Electrostatic Discharge Protection
- Cellular Phone Interference |
| Software validation | - Implant software validation
- Programmer software validation |
Biocompatibility testing was not performed, due to the successful history with the same materials in other pacemakers. Sterilization testing and mechanical / environmental packaging validation were performed, because the pacemaker package design and sterilization method changed. All test results demonstrated that the established pass / fail criterion was met in all cases.
## Conclusion
The information presented in this submission provides reasonable assurance that the Opus S Model 4121 and 4124 pacemakers will perform in a safe and effective manner.
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DEPARTMENT OF HEALTH & HUMAN SERVICES
Public Health Service
Food and Drug Administration
9200 Corporate Boulevard
Rockville MD 20850
AUG 29 1997
Ms. Catherine G. Goble
Regulatory Affairs Manger
Ela Medical
2950 Xenium Lane North
Plymouth, MN 55441
Re: K970072
Trade Name: Opus S Model 4121 and 4124 Single Chamber Pacemakers
Regulatory Class: III (3)
Product Code: DXY
Dated: August 20, 1997
Received: August 21, 1997
Dear Ms. Goble:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent to 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). 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 (Premarket Approval), 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 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.
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Page 2 - Ms. Catherine G. Goble
This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate 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 and additionally 809.10 for *in vitro* diagnostic devices), please contact the Office of Compliance at (301) 594-4639. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597, or at its internet address "http://www.fda.gov/cdrh/dsmamain.html".
Sincerely yours,

Thomas J. Callahan, Ph.D.
Director
Division of Cardiovascular, Respiratory and Neurological Devices
Office of Device Evaluation
Center for Devices and Radiological Health
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# Indications for Use Statement
510 (k) Number: K970072
Device Name: Opus S Model 4121 and 4124 pacemakers.
Indications for Use:
- AV conduction disorders or intraventricular paroxysmal/permanent conduction disorders with permanent atrial tachycardia: atrial fibrillation or flutter (lead implanted in the ventricle),
- Sinus bradycardia, sinoatrial block, brady-tachy syndrome without atrioventricular conduction disorder (lead implanted in the atrium).
Concurrence of CDRH, Office of Device Evaluation (ODE)

Prescription Use ☑
(Per 21 CFR 801.109)
OR
Over-The-Counter Use ☐
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.
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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.
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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.
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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.
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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.
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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.
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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.