The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 12, 1991
Filed:
Mar. 30, 1989
John C Moore, Tulsa, OK (US);
Invivo Research, Inc., , US;
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.