The system is intended for noninvasive examinations via esophageal electrostatic copying method and noninvasive heart electrostimulation, as well as for stress testing with atrium stimulation to detect myocardial ischemia
- dedicated portable recording block of ECG and esophageal leads , cable, a set of electrocardiographic electrodes, esophageal pumps; software for noninvasive heart examination
- programmable electrostimulator
Taking into consideration potentional risk of stress tests and correspondently the necessity of computer and software safety,the system is equiped with:
- fault-tolerant dedicated (industrial) computer, which provides no-break operation in unattended mode during long time
- medical power unite, which provides adequacy to medical standards of electrical safety and radio noise
- Windows Embedded operating system, that is specially designed to provide productivity and safety of devices with higher reliability level
The system allows ECG recording in 12 leads and esophageal electrogram simultaneously. Recorded data is performed on the PC screen in real time (4 speeds of oscillogram movements are available) on the set number of channels(1 to 15). Filtered oscillograms are performed on the screen in real time. 4 different colors (out of 256) can be set by the user for curves, as well as for markers of stimuli. Current HR and time of the measurement are always viewed. Specified data can be constantly logged on the HDD during whole measurement at a set number of channels.
During measurement the user can "Stop" oscillogram movements for more detail processing and measurements while data recording continues. The notable feature of the system is the ability of recording esophageal electrogram from electrodes concurrently with electrostimulation.
Programmable digital filter is used to view recorded esophageal electrograms. The range of gating frequency is set by the user. Digital filters work both in real time and during analysis. At that in real time working the ocillograms that move on the screen are filtered signals.
Additionally the system can be supplied with a set of programs for automation of noninvasive EPI (defining of HR parameters, threshold of stimulation, time of sino-atrial conduction, time of functional recovery of sinus node, Wenckebach point, refractory period of atrioventricular conducting system, estimation of ST-segment and HR dynamics and etc.)
The system allows programming and changing of series and parameters of stimulator impulses during work. The stimulator is started and operated both in manual and automatic modes. "Pause" and "Repeat" functions are available. Programming of electrostimulation is realized by means of numeral setting of required parameters in special blocks and setting a chain of blocks' switching. In each block it is set (manually): voltage, impulse length, linkage interval (with R-waves or previous stimulus), pause after series of impulses, period of impulse following and frequency, number of impulses in a series or the length of the series in time. The Linkage interval can be changed in manual mode (discontinuity - 1 ms) or in automatic mode ("decrement ", "increment" with minimal step 1 ý˝) with indication of current interval.
Stimulator allows programming the main types of heart electrostimulation are used in clinic electrophysiological investigations. Markers of stimulus are viewed on the screen while stimulation.
Recorded during the ECG measurement data is performed in HR trend and full compression record (full disclosure) of the one of the chosen channels by which the search of necessary part of the record was realized for further detailed processing.
ECG viewing is performed in multichannel image of native record in a selected scale with possibility of smooth or discrete shifting along it. A that markers and parameters of the electrostimulus are set. Measurement of temporary intervals and amplitude characteristics is realized with a high accuracy with the help of the special viewfinder setting. During viewing any of the recorded channels can be filtered at user set frequency without changes in native record on the HDD.
System is based on a special database which allows saving and systematizing of records and also results of its analyzing. HHD of the computer is used for operative data saving, for long-term storage of large data CD or DVD dicks are used.
System provides high-quality ECG prints on the laser printer with speed from 5 to 400 mm/s on A4 sheets and in a full compression ECG prints in one lead.