Apparatus and method for automatic lead selection in electrocardiography
US4577639A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 8, 1984 |
| Grant date | Mar 25, 1986 |
| Priority date | — |
| Expiry date | Nov 8, 2004 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/28
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An ECG electrode impedance measuring approach is utilized which can determine, simultaneously, the condition of all electrodes in a three or five lead ECG monitoring configuration. A CPU automatically selects an ECG lead configuration in which all electrodes are attached to the patient and are below an impedance threshold. If the CPU cannot select a good ECG lead configuration, then the CPU signals a total lead failure. Electrode impedance is determined by passing a small DC current through each active electrode and the current is returned via the reference electrode. A comparator tests the resultant offset voltage induced between each active electrode and the reference. If the offset voltage exceeds a fixed threshold, then a flag is set and transferred to the CPU. The CPU can change the ECG lead configuration by issuing commands to an electrode lead switching network. The CPU software tests each lead configuration in a logical sequence to find one in which all the necessary electrodes are functional and a good quality ECG waveform can be processed and displayed. If a useable lead configuration cannot be found, then an alarm is activated to alert the operator to check all electrode…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.