摘要:
A lead extending exteriorly from an active implantable medical device (AIMD) is at least partially ensheathed within an electromagnetic interference (EMI) shield. The AIMD has a conductive equipotential surface to which the EMI shield may be conductively coupled. An impeding circuit may be provided for raising the high frequency impedance of the lead. An energy diversion circuit may also be provided for conductively coupling the lead to the EMI shield.
摘要:
An electrical energy storage device such as a wet tantalum electrolytic capacitor or an electrochemical cell such as a lithium/silver vanadium oxide cell is described. The enclosure comprises a drawn casing portion having a planar face wall supporting a surrounding sidewall and is shaped to nest the anode, cathode and intermediate separator components. A mating cover is a stamped planar piece of similar material having a periphery edge welded to the edge of the casing portion surrounding sidewall. In order to prevent heat generated during the welding process from damaging the separator, the anode portion adjacent to the weld site is contoured. This provides sufficient space between the weld and the separator supported on the anode at the contour so that what heat is transmitted to the separator by convection and conduction mechanism will not damage the separator.
摘要:
An RFID tag is disposed within a hermetically sealed housing of an IMD. Low frequency RFID interrogators and tags are used, and the housing walls are made of materials, and/or are reduced in thickness, to facilitate RF communication between the RFID tag and an RFID reader/interrogator programmer. An RFID reader/interrogator may be used which has a limited transmit time and time-out period to avoid interference with the operation of the IMD.
摘要:
A capacitor having a cylindrical shape or configuration so that it is capable of being inserted directly into the vasculature of a patient is described. A typical diameter for the present capacitor is about 6 mm. A capacitor of this size would occupy about 9% of the total cross-sectional area of the inferior vena cava prior to the crossover to the heart, where the typical diameter of the vein is about 20 mm. The crossover section has a diameter of about 11 mm to about 12 mm.
摘要:
A lead extending exteriorly from an active implantable medical device (AIMD) is at least partially ensheathed within an electromagnetic interference (EMI) shield. The AIMD has a conductive equipotential surface to which the EMI shield may be conductively coupled. An impeding circuit may be provided for raising the high frequency impedance of the lead. An energy diversion circuit may also be provided for conductively coupling the lead to the EMI shield.
摘要:
An electrical energy storage device such as a wet tantalum electrolytic capacitor or an electrochemical cell such as a lithium/silver vanadium oxide cell is described. The enclosure comprises a drawn casing portion having a planar face wall supporting a surrounding sidewall and is shaped to nest the anode, cathode and intermediate separator components. A mating cover is a stamped planar piece of similar material having a periphery edge welded to the edge of the casing portion surrounding sidewall. In order to prevent heat generated during the welding process from damaging the separator, the anode portion adjacent to the weld site is contoured. This provides sufficient space between the weld and the separator supported on the anode at the contour so that what heat is transmitted to the separator by convection and conduction mechanism will not damage the separator.
摘要:
An enclosure for an electrical energy storage device such as a wet tantalum electrolytic capacitor or an electrochemical cell such as a lithium/silver vanadium oxide cell is described. The enclosure comprises two metallic casing components or portions. The first is a drawn member having a planar face wall supporting a surrounding sidewall and is shaped to nest the anode, cathode and intermediate separator components. The surrounding sidewall has an annular flange at its outer periphery. A mating cover is a stamped planar piece of similar material whose periphery fits inside the annular flange or rim as a complementary piece.
摘要:
A composite RF current attenuator for a medical lead includes a conductor having a distal electrode contactable to biological cells, a bandstop filter in series with the lead conductor for attenuating RF currents flow through the lead conductor at a selected center frequency or across a range of frequencies about the center frequency, and a lowpass filter in series with the bandstop filter and forming a portion of the lead conductor. The bandstop filter has a capacitance in parallel with a first inductance. In a preferred form, the lowpass filter includes a second inductance in series with the bandstop filter, wherein the values of capacitance and inductances for the composite RF current attenuator are selected such that it attenuates MRI-induced RF current flow in an MRI environment.
摘要:
A composite RF current attenuator for a medical lead includes a conductor having a distal electrode contactable to biological cells, a bandstop filter in series with the lead conductor for attenuating RF currents flow through the lead conductor at a selected center frequency or across a range of frequencies about the center frequency, and a lowpass filter in series with the bandstop filter and forming a portion of the lead conductor. The bandstop filter has a capacitance in parallel with a first inductance. In a preferred form, the lowpass filter includes a second inductance in series with the bandstop filter, wherein the values of capacitance and inductances for the composite RF current attenuator are selected such that it attenuates MRI-induced RF current flow in an MRI environment.