Related Experiment Video
Updated: Aug 1, 2026
09:35
Fabrication of High Contact-Density, Flat-Interface Nerve Electrodes for Recording and Stimulation Applications
Published on: October 4, 2016
Failure of demand pacing with small surface area electrodes
Circulation
|July 11, 1976
Summary
Smaller pacemaker electrodes require less energy for heart stimulation but can impair R-wave signal transmission. Optimizing circuit impedance is crucial for small electrodes to prevent sensing issues.
Area of Science:
- Biomedical Engineering
- Cardiovascular Electrophysiology
Background:
- Pacemaker electrode size affects stimulation energy, but its impact on R-wave potential transmission is unclear.
- Current trends favor smaller electrodes to conserve pacemaker battery life.
Purpose of the Study:
- To investigate the relationship between pacemaker electrode surface area and R-wave potential amplitude.
- To determine how electrode surface area influences sensing capabilities and stimulation thresholds.
Main Methods:
- R-wave potentials were measured in canine subjects using various pacemaker electrodes with differing surface areas.
- Measurements included endocardial and intramyocardial recordings under a consistent load impedance (1000 ohms).
Main Results:
- A direct correlation was observed between electrode surface area and measured R-wave potentials.
- Decreased surface area led to reduced R-wave amplitude, indicating diminished signal conduction.
- R-wave potential amplitude correlated directly with threshold current and energy requirements.
Conclusions:
- Pacemaker electrode surface area significantly impacts R-wave signal sensing.
- Smaller electrodes, while reducing stimulation energy, may compromise sensing performance.
- Optimizing pacemaker circuit impedance is essential when using small surface area electrodes to avoid sensing problems.
Related Concept Videos
01:16Equipotential Surfaces and Conductors
For a conductor in which all charges are at rest, the conductor's surface is equipotential. The electric field is always perpendicular to equipotential surfaces. Therefore, in a conductor with static charges, the electric field just outside the conductor is always perpendicular to the conductor's surface. Any tangential component of the electric field will cause charges to move inside the conductor, which will violate the electrostatic nature of the system. In an electrostatic situation, if a...
01:26Energy Stored in a Capacitor: Problem Solving
In 1749, Benjamin Franklin coined the word battery for a series of capacitors connected to store energy. Capacitors store electric potential energy that can be released over a short time. This property means capacitors have a wide range of applications.
Capacitor-discharge ignition is a type of ignition system commonly found in small engines where the energy released from a capacitor ignites an induction coil that, in turn, fires the spark plug.
To calculate the energy stored in a capacitor of...
Capacitor-discharge ignition is a type of ignition system commonly found in small engines where the energy released from a capacitor ignites an induction coil that, in turn, fires the spark plug.
To calculate the energy stored in a capacitor of...
01:16Electrostatic Boundary Conditions
Consider an external electric field propagating through a homogeneous medium. When the electric field crosses the surface boundary of the medium, it undergoes a discontinuity. The electric field can be resolved into normal and tangential components. The amount by which the field changes at any boundary is given by the difference between the field components above and below the surface boundary.
The surface integral of an electric field is given by Gauss's law in integral form and is related to...
The surface integral of an electric field is given by Gauss's law in integral form and is related to...
01:27Electrostatic Boundary Conditions in Dielectrics
When an electric field passes from one homogeneous medium to another, crossing the boundary between the two mediums imparts a discontinuity in the electric field. This results in electrostatic boundary conditions that depend on the type of mediums the field propagates through.
Consider a case where both the mediums across a boundary are two different dielectric materials. Recall that the electric field and electric displacement are proportional and related through the material's permittivity.
Consider a case where both the mediums across a boundary are two different dielectric materials. Recall that the electric field and electric displacement are proportional and related through the material's permittivity.
01:10Energy Stored in Capacitors
A parallel plate capacitor, when connected to a battery, develops a potential difference across its plates. This potential difference is key to the operation of the capacitor, as it determines how much electrical energy the capacitor can store.
By integrating the equation that relates voltage and current in a capacitor, one can derive an equation for the voltage across the capacitor at any given time. This equation is crucial in understanding and predicting the behavior of capacitors in...
By integrating the equation that relates voltage and current in a capacitor, one can derive an equation for the voltage across the capacitor at any given time. This equation is crucial in understanding and predicting the behavior of capacitors in...
01:27Schottky Barrier Diode
Schottky barrier diodes are specialized semiconductor devices characterized by their unique construction. This construction involves combining a metal layer with a moderately doped n-type semiconductor material. This combination leads to the formation of a Schottky barrier, a pivotal element that defines the diode's operational characteristics. The core functionality of Schottky barrier diodes is their capacity to allow current to flow in only one direction due to their distinctive...