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ECG, EKG |
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| ECG may be recorded from either humans or animals using ADInstruments Bio Amplifier and PowerLab. |
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 The electrocardiogram is a recording of electrical activity associated with cardiac events. It is a non-invasive technique that is commonly used by researchers as a measure of cardiac function. Specific waveforms within the ECG represent the electrical activity associated with mechanical events such as ventricular contraction and relaxation (systole and diastole).
There are several methods for the measurement ECG. ECGs are bioelectrical signals that can be recorded using electrodes connected to a biological amplifier via leads. Although an ECG may be obtained using three electrodes (3 Leads ECG - Positive, Negative and Earth), these bioelectrical signals also occur in more than a single dimension as the heart is three dimensional. Therefore evaluation of the ECG in all three dimensions will give a more accurate ECG assessment. In humans, this is achieved using higher number of electrodes in various arrangements. Some of these arrangements include: - 5 Leads ECG
- 6 Leads ECG
- 12 Leads ECG
Various methods of connecting the electrodes for the measurement of 3 Lead ECG
Measurement of 12 Leads ECG
For additional information see: - Isolated Heart Preparations: Langendorff and Working Heart Preparations that commonly incorporate ECG recordings when investigating cardiac function.
- Our other biopotential application pages: EEG & ECoG, EMG, EOG and ERG.
LabChartLabChart software (for Windows and Macintosh) combines the familiar simplicity of a traditional strip chart recorder with the powerful analysis features of a digital acquisition system. LabChart software and a PowerLab data acquisition unit provide data integrity, easy selection of hardware settings, powerful online and offline analysis, procedure automation, seamless extraction of experimental data and flexible display options. Acquisition and analysis capabilities can be further increased with LabChart Extensions and LabChart Modules. LabChart Modules are available as part of LabChart Pro and LabChart Extensions are free for download from the website for existing LabChart users. LabChart users can calculate and display online or offline heart rate using features such as Cyclic Measurements (Cycle variables, Mac) in LabChart. The mean and standard deviation of the heart rate can also be calculated (over any time interval) using the Data Pad feature in LabChart. ECG Analysis Module (Windows)The MLS360/6 ECG Analysis Module provides a comprehens ive set of tools that automatically detects and reports values of ECG recordings. The software can be used with ECG recordings taken from humans and many species of animals from pigs through to mice.
It provides
- Real-time analysis and data extraction of ECG parameters
- PQRST amplitudes
- Time intervals such as RR, PR, JT, QT and QTc
- Analysis of ECG parameters in real-time or offline
- Automated detection and averaging of ECG cycles
- Automated tabulation and data extraction of ECG parameters
- Automated real-time or offline ECG Plots
- Graphical QT vs RR, QT vs Time & RR vs Time plots
- Waterfall plot
Heart Rate Variability (HRV) Module (Windows or Macintosh)
The MLS310 HRV Module provides a comprehensive set of tools for the analysis and display of variation in the interval between heartbeats in human and animal electrocardiogram recordings.
It provides:
- Detects and analyzes of R waves & RR interval variation in ECG real-time or offline recordings
- Includes or excludes ectopic beats from analysis
- Adds R waves or remove short artifacts from analysis
- Exports data analysis
- NN Intervals, RR Intervals, Spectrum NN Intervals & Report
- Automated HRV Analysis Windows
- Poincaré Plot, Tachogram & Spectrum
- Period Histogram & Delta NN Histogram
- Cardiac Axis LabChart Extension: Automate the calculation of frontal plane ECGs and vector cardiograms and display of the instantaneous cardiac vector.
- SAECG (signal averaged ECG) LabChart Extension (MAC only): Calculates the average cycle of ECG signals and automatically identifies specification waveforms and cardiac indices.
- Peak Parameters LabChart Extension: Determines a number of parameters for an individual peak and is ideal for analyzing cardiac action potentials.
GLP and 21 CFR Part 11
For those researchers working within a laboratory requiring GLP and 21 CFR Part 11 compliance the GLP Client and GLP Server are available for use with LabChart (Windows only) and PowerLab data acquisition systems. For more information, visit the Good Laboratory Practice application page or contact your nearest ADInstruments representative.
A PowerLab data acquisition system can be used with other brands and models of amplifier to record the ECG/EKG, provided they have a suitable analog output (Maximum ±10 V). PowerLab Data Acquisition Systems The PowerLab are high-performance data acquisition units suitable for a wide range of research applications. Typical applications include human and animal physiology, pharmacology, neurophysiology, biology, zoology, biochemistry, and biomedical engineering. Units are compatible with instruments, signal conditioners and transducers supplied by ADInstruments, as well as many other brands. In addition to standard single-ended BNC inputs, differential Pod ports are also available for direct connection of Pod signal conditioners and appropriate transducers. These units include:Research PowerLabs Telemetry ECG/Biopotential Foundation SystemThis ML870B99 Telemetry ECG/Biopotential Foundation System comprises of hardware and software to record and analyze one biopotential signal such as ECG, EMG, EOG or EEG, as well as body temperature, from conscious animals. The system includes: - The ML319 TR Scheduler Pod and LabChart Scheduler Extension that allows the user to program recording periods as well as record data from up to 12 individual transmitters/animals.
- Uses implantable wireless transmitters
- Requires no special caging due to independent frequency transmission
- Suitable for small or large animals
- Allows long-term, stress-free recording
Transmitters are purchase separately and the recommended transmitters are: Bio Amplifiers The ECG biopotentials are typically very small in amplitude (mV). Therefore accurate recording, display and analysis of an ECG require a suitable bioamplifier. ADInstruments offer a range of Bio Amplifiers, when connected a PowerLab data acquisition unit and, are certified safe for use with humans or used with animals. These bioamplifiers are fully software-controlled using LabChart or Scope. The following ADInstruments' biological amplifiers are fully isolated for connection to human or animal subjects: ML132 Bio Amp ML135 Dual Bio Amp ML408 Dual Bio Amp/Stimulator If a Dual Bio Amp is used to record any two signals of Lead I or Lead II or Lead III, then the Arithmetic function of the LabChart software can be used to generate aVR, aVL, and aVF signals simultaneously on different channels. The MLA0114/S ECG 12 Lead Switch Box (with a ML132 Single Bio Amp) or MLA0114/D ECG 12 Lead Switch Box (with a Dual Bio Amp) can be used to record all 12 ECG leads as shown in multi-lead recording. ML138 Octal Bio Amp - A differential amplifier that consists of eight electrically isolated differential input AC amplifiers
- A shared ground connection across all eight inputs.
- Supplied with two packets of MLA0310 Lead Wires (1.8 m, 10 snap on)
GT201/F 16 Channel Bio Amp - A fully isolated, 16 channel stand-alone biological amplifier that consists of 8 modules, with each module containing two channel amplifiers that share a common ground input
- Electrodes are NOT supplied and must be ordered separately
- Suitable electrodes and lead wires include the:
The following ADInstruments' biological amplifiers for use with animals (i.e. pithed toad, or anaesthetized rat/mouse) only: ML136 Animal Bio Amp - An isolated, high performance and software-controlled differential amplifier
- Has three 2mm input sockets allow the direct connection of electrodes to this amplifier
- Supplied with MLA1215 Animal Bio Lead Wires
- Also suitable for use with
ECG Switch Boxes - For multi-lead recordings, ADInstruments Bio Amps (Bio Amp, Dual Bio Amp, Dual Bio Amp/Stim) can be used with the ECG Switch Boxes (MLA0114/S or MLA0114/D) to quickly change between Lead I, II, II, aVR, aVL, aVF, and V1 - V6 lead configurations
- Only one lead configuration is recorded at any one time
- For the V1 - V6 configurations, the position of the chest electrode must be changed, which is most easily done by using MLA710 Chest ECG Electrodes (suction)
- Not suitable for use with the Multiple Channel Bio Amps
AccessoriesBio Amp cables: Leads compatible with both shielded (MLA2340 & MLA2540) and unshielded (MLA1340 & MLA1540) cables: Leads compatible with shielded cables (MLA2340 & MLA2540) only: Leads that directly connect to the Dual Bio Amp Leads that directly connect to the Animal Bio Amp Electrodes:
| The parasympathetic nervous system: its role during torpor in the fat-tailed dunnart (Sminthopsis crassicaudata) |
| G R Zosky, Journal of Comparative Physiology B, 677-684, 2002 |
| adult fat-tailed dunnarts weighing 17.3±1.3 g were used to perform experiments in a soundproof, temperature-controlled room set at a 12:12-h light-dark cycle and a temperature of 13ºC continuously. The electrocardiogram (ECG), used to obtain a heart rate, and ventilation rate were measured by placing the animals in a sealable, ventilated, clear plastic tube that was 8 cm long and 4 cm wide. The electrodes used to monitor the ECG consisted of a pair of Bio Tab (ADInstruments) AgCl electrode pads glued to a piece of cardboard that formed the removable base of the plastic tube. Electrical contact was maintained by the dunnart standing on the electrodes. The signal was amplified through an ML110 Bio Amp (ADInstruments) connected to a MacLab 4/s (ADInstruments) and recorded on a Macintosh computer using Chart 3.6.3 (ADInstruments). Ventilation rate was measured simultaneously using an MLT1010 pulse transducer (ADInstruments). The transducer was glued to one end of the sealable tube so that the dunnart’s chest would rest against it, allowing ventilatory movements to be detected. The transducer was connected directly to the MacLab and recorded using the same software described above. |
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| Abrupt rate accelerations or premature beats cause life-threatening arrhythmias in mice with long-QT3 syndrome |
| D Nuyens, M Stengl, S Dugarmaa, T Rossenbacker, V Compernolle, Y Rudy, J F Smits, W Flameng, C E Clancy, L Moons, M A Vos, M Dewerchin, K Benndorf, D Collen, E Carmeliet and P Carmeliet, Nature Medicine, 1021, 2001 |
| Anesthetized mice (Na+ pentobarbital; 70 mg/kg intraperitoneally) were placed on a heating pad with continuous monitoring of body temperature. Eight-lead ECGs were recorded using needle electrodes (subcutaneously implanted in each limb; 2 electrodes at precordial position V2 and V6) using an adapted front-end Siemens mingograph with bandpass filtering between 0.03 Hz and 1 kHz. Supplementary amplification and A/D conversion were performed using a Powerlab 16S (AD Instruments, Hastings, UK). Digital recordings (16 bit, 4 kHz/channel) were analyzed using the Chart v4.0 program (ADInstruments). The signal averaged ECG (SAECG) was calculated using the mouse SAECG extension v1.2 program (AD Instruments) and a template matching algorithm. |
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The material on this page is provided in good faith and believed accurate at the time of writing. No responsibility will be taken, or liability accepted, for damages arising from the use of information herein. Readers are urged to check with respective manufacturers the accuracy of all product related information.
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