Method of improving the quality of an electrocardiogram obtained from a patient undergoing magnetic resonance imaging
US4991580A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 30, 1989 |
| Grant date | Feb 12, 1991 |
| Priority date | — |
| Expiry date | Mar 30, 2009 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/308
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A method for improving the quality of electrocardiogram (ECG) signals for input to a cardiac monitor and obtained from a patient undergoing magnetic resonance imaging (MRI) wherein the ECG leads attached to the patient are exposed to rapidly changing magnetic fields produced by the MRI which induce relatively high levels of rapid voltage changes in the ECG leads, the method including the steps of conducting the ECG signals having MRI induced noise signals superimposed thereon to the input of a slew rate limiter (SRL) circuit having a preselected maximum slew rate, the circuit providing an output signal having a maximum dv/dt which is slightly greater than the maximum typical ECG dv/dt, connecting the output of the SRL circuit to the input of a low pass filter circuit having an attenuation above the ECG typical fundamental frequency and connecting the output of the low pass filter circuit to a cardiac monitor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.