Patent ID: 8849413
Filing Date: 2014-09-30
Classification: A61N,H03H

Abstract:
1. A lead for an implantable medical device, comprising: at least one electrode; at least one conductor; a resistive component positioned between the at least one electrode and at least one conductor and configured to protect against a current induced by a magnetic field during an MRI procedure; one or more switching components having a first configuration and a second configuration, wherein, in the first configuration, the one or more switching components are configured to provide a short circuit across the resistive component and provide a path for current to flow from the at least one conductor to the at least one electrode around the resistive component, and wherein, in the second configuration, the one or more switching components are configured to open the short circuit, such that the only path for current to flow from the at least one conductor to the at least one electrode is through the resistive component; a control circuit configured to control the one or more switching components to place the one or more switching components in the first configuration or the second configuration, wherein the control circuit is configured to detect a stimulation pulse based on a voltage of the stimulation pulse and to place the one or more switching components in the first configuration for a duration of the stimulation pulse; a filter circuit configured to at least partially block signals having a first range of frequencies associated with signals induced by the magnetic field during the MRI procedure, wherein the filter circuit is further configured to at least partially pass signals having a second range of frequencies associated with stimulation pulses; and a selectively modifiable impedance dipole connected in series between the at least one electrode and the at least one conductor, wherein the selectively modifiable impedance dipole comprises the resistive component.