How the First Automatic Implantable Defibrillator Works
A 1970 invention by Medtronic that monitors heart rhythms and automatically delivers an electric shock to restart the heart if it detects a dangerous malfunction.
Original patent title: “Electronic standby defibrillator”
A 1970 invention by Medtronic that monitors heart rhythms and automatically delivers an electric shock to restart the heart if it detects a dangerous malfunction. Granted to Medtronic Inc in 1971 with 71 forward citations, and it is now in the public domain.
Key facts
Coverage
What does this patent actually cover?
The device acts as a continuous heart monitor that tracks electrical activity to identify life-threatening arrhythmias. When the system detects an abnormal heart rhythm, it triggers a high-voltage discharge to shock the heart back into a normal sinus rhythm. If the first shock fails to restore normal function within a set interval, the mechanism is designed to deliver subsequent shocks. The device remains inactive as long as the heart's electrical activity stays within normal parameters.
The gap
What does this patent NOT cover?
- Does not cover external defibrillators that require manual operation by a human.
- Does not cover devices that monitor blood pressure or oxygen levels rather than electrical heart activity.
- Does not cover pacemakers that only provide low-voltage stimulation for slow heart rates.
These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.
What made this novel
The invention shifted the paradigm from external, reactive emergency care to an autonomous, internal system that waits in a standby state until it detects a specific, lethal electrical signature.
The Patent Drawing
Schematic visualization of the patent's claim structure. Hand-drawn diagrams in progress for each landmark patent.
Where you've seen this
Real-world examples
Modern implantable cardioverter-defibrillators (ICDs)
Subcutaneous ICDs (S-ICD)
Why it matters
The bigger picture
This patent represents the foundational technology for the Implantable Cardioverter Defibrillator (ICD). It transformed the treatment of sudden cardiac arrest by enabling a device to provide life-saving intervention without requiring a doctor or bystander to be present.
Filed
February 9, 1970
Granted
October 26, 1971
Market context
Who's building on this
Companies in this space
Medtronic remains a dominant force in this space, having commercialized the technology derived from this early work. Other major medical device companies like Boston Scientific and Abbott Laboratories continue to advance ICD technology with smaller leads and smarter sensing algorithms.
Market impact
This patent laid the groundwork for a multi-billion dollar market in cardiac rhythm management. It effectively created the category of implantable life-support devices, shifting the standard of care for patients at high risk of sudden cardiac death.
Claim 1 — Plain English
What this patent covers
The device acts as a continuous heart monitor that tracks electrical activity to identify life-threatening arrhythmias. When the system detects an abnormal heart rhythm, it triggers a high-voltage discharge to shock the heart back into a normal sinus rhythm. If the first shock fails to restore normal function within a set interval, the mechanism is designed to deliver subsequent shocks. The device remains inactive as long as the heart's electrical activity stays within normal parameters.
The clever bit
The invention shifted the paradigm from external, reactive emergency care to an autonomous, internal system that waits in a standby state until it detects a specific, lethal electrical signature.
What it does not cover
- Does not cover external defibrillators that require manual operation by a human.
- Does not cover devices that monitor blood pressure or oxygen levels rather than electrical heart activity.
- Does not cover pacemakers that only provide low-voltage stimulation for slow heart rates.
Patent Journey
From filing to expiry
PatentBrief Score
Impact Score
Moderate
Citation count
37/40
Highly cited
Claim breadth
0/20
Narrow claimsclaimsThe numbered statements at the end of a patent that legally define what the inventor owns.Read more →
Recency
0/20
Older than 20 years
Assignee scale
20/20
Major company or institution
PatentBrief Impact Score — based on citation count, claim breadth, recency, and assignee scale. Not a legal assessment.
Heuristic Value Estimate
What this patent might be worth
$40K – $127K
Midpoint $79K · expired or expiring · industry ×2.2
Heuristic only — blends forward/backward citation counts, claim scope, time remaining, litigation history, and CPC-derived industry baseline. Real valuations need a professional appraisal.
Concepts involved
Citations
Patent lineage
Cite this patent
Mirowski, M., Mower, M. M., & Staewen, W. S. (1971). How the First Automatic Implantable Defibrillator Works (U.S. Patent No. 3,614,954). U.S. Patent and Trademark Office. https://patentbrief.org/patent/us/3614954/implantable-defibrillator-mirowski
Auto-generated from the patent record. Double-check author order and the issue date against the official USPTO document before submitting.
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Common Questions
Frequently Asked Questions
What does How the First Automatic Implantable Defibrillator Works cover?
A 1970 invention by Medtronic that monitors heart rhythms and automatically delivers an electric shock to restart the heart if it detects a dangerous malfunction.
Who owns patent US 3614954?
Medtronic Inc owns this patent, granted in 1971.
When does this patent expire?
This patent has expired and is now in the public domain — anyone can use the invention freely.
What is patent US 3614954 cited by?
This patent has been cited by 71 later patents that build on its ideas.
What problem does this patent solve?
This patent represents the foundational technology for the Implantable Cardioverter Defibrillator (ICD). It transformed the treatment of sudden cardiac arrest by enabling a device to provide life-saving intervention without requiring a doctor or bystander to be present.
What does this patent NOT cover?
Does not cover external defibrillators that require manual operation by a human.
Patent monitoring