Related Experiment Video
Updated: Jun 22, 2026
05:44
Performing In Vivo and Ex Vivo Electrical Impedance Myography in Rodents
Published on: June 8, 2022
Myocardial electrical activity does not affect myocardial electrical impedance measurements
Roger Dzwonczyk1, Carlos del Rio, Thomas D McSweeney
1Department of Anesthesiology, The Ohio State University, Doan Hall, Columbus, OH 43210-1228, USA. dzwonczyk.1@osu.edu
Journal of Clinical Monitoring and Computing
|June 23, 2009
Summary
This study found that changes in heart rate (HR) due to drugs do not affect myocardial electrical impedance (MEI) measurements. The novel MEI monitor accurately measures ischemia regardless of heart rate variations.
Area of Science:
- Cardiovascular Physiology
- Biomedical Engineering
- Ischemic Heart Disease Research
Background:
- Myocardial electrical impedance (MEI) is a valuable indicator of myocardial ischemia.
- A novel monitor for near-real-time MEI measurement has been developed.
- The impact of heart rate (HR) variability on MEI measurements requires investigation.
Purpose of the Study:
- To evaluate if drug-induced alterations in heart rate (HR) affect myocardial electrical impedance (MEI) measurements.
- To validate the reliability of a novel MEI monitor under varying cardiac electrical frequencies.
- To assess the MEI monitor's performance during induced myocardial ischemia.
Main Methods:
- Thirty dogs were divided into placebo, isoproterenol, and esmolol groups.
- Anesthesia, intubation, ventilation, and catheterization were performed.
- The left anterior descending (LAD) coronary artery was isolated, and MEI was measured during occlusion after drug administration.
Main Results:
- Isoproterenol increased HR, while esmolol decreased HR, with neither affecting MEI measurements.
- Myocardial electrical impedance (MEI) increased during LAD coronary artery occlusion across all groups.
- The developed MEI monitor demonstrated consistent measurements irrespective of HR changes.
Conclusions:
- The novel MEI monitor is not influenced by heart rate (HR) variations.
- This finding supports the use of the MEI monitor for reliable ischemia detection.
- The monitor's independence from cardiac electrical activity frequency enhances its clinical applicability.
More Related Videos
Related Concept Videos
01:30Cardiac Action Potential
Cardiac action potentials are essential for proper heart function, enabling the rhythmic contractions needed for adequate blood circulation. Nodal cells and Purkinje fibers, specialized for electrical conduction, generate these action potentials.
The cardiac action potential process involves a series of phases characterized by the movement of ions across the cardiac cell membranes, leading to the depolarization and repolarization of the cardiac myocytes.
Ionic Basis of Cardiac Action Potentials
The cardiac action potential process involves a series of phases characterized by the movement of ions across the cardiac cell membranes, leading to the depolarization and repolarization of the cardiac myocytes.
Ionic Basis of Cardiac Action Potentials
01:19Electrophysiology of Normal Cardiac Rhythm
The normal cardiac rhythm is a synchronized electrical activity that facilitates the regular and coordinated contraction of the heart muscle. This process is essential for efficient blood circulation throughout the body. The fundamental elements involved in establishing and maintaining this rhythm include the unique electrical properties of cardiac muscle cells, the sinoatrial (SA) node's pacemaker function, the specialized conducting system, and the ionic mechanisms underlying each phase of...
01:28Mechanism of Cardiac Arrhythmias
Arrhythmias are irregular heart rhythms occurring when the heart's electrical impulses become abnormal. These disturbances can lead to various symptoms, depending on their severity and the underlying cause. Some common factors contributing to arrhythmias include hypoxia, ischemia, electrolyte imbalances, excessive catecholamine exposure, drug toxicity, and muscle overstretching. Arrhythmias can be classified into two main types based on the rate and site of origin of abnormal heart rhythms.
01:29Electrocardiogram
An electrocardiogram (ECG or EKG) is a critical diagnostic tool that records the electrical signals produced by the heart during each heartbeat. This recording is achieved through electrodes placed strategically on the arms, legs, and chest. The electrocardiograph amplifies these signals and produces 12 distinct tracings, offering a comprehensive understanding of the heart's electrical activity.
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and the T...
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and the T...