Implantable cardioverter defibrillator designed for use in a magnetic resonance imaging environment

Abstract

An implantable cardioverter defibrillator includes a communication interface operable to receive a communication signal from an external programmer. The communication signal includes a command to switch the ICD from a first mode to a second mode. A processor is in electrical communication with the communication interface and configured to switch the ICD between the first and second modes. A battery is configured to supply low DC voltage. A converter is configured to convert the low DC voltage to a high DC voltage. An energy storage capacitor is electrically coupled to the converter and configured to store a therapeutic energy or high DC voltage including at least 15 joules. The second mode includes activating the converter to convert the low DC voltage to the high DC voltage and storing the therapeutic energy or at least 15 joules within the energy storage capacitor during a period of time of the second mode.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This utility application claims priority to provisional application 61 / 525,235 filed on Aug. 19, 2011.DESCRIPTION FIELD OF THE INVENTION[0002]The present invention generally relates to implantable cardioverter defibrillators. More particularly, the present invention relates to an implantable cardioverter defibrillator that can operate during medical diagnostic procedures such as magnetic resonant imaging.BACKGROUND OF THE INVENTION[0003]Magnetic resonance imaging (MRI) is an efficient technique used in the diagnosis of many disorders, including neurological and cardiac abnormalities and other diseases. MRI has achieved prominence in both the research and clinical arenas. It provides a non-invasive method for examining internal body structures and functions. Because MRI has become such a useful diagnostic tool, it now is used extensively in hospitals and clinics around the world.[0004]Magnetic resonance imaging equipment produces three mai...

AI Technical Summary

Benefits of technology

[0008]An exemplary embodiment of an implantable cardioverter defibrillator (ICD) is disclosed including a hermetically sealed housing and a communication interface disposed within the housing operable to receive a communication signal from an external programmer. The communication signal includes a command to switch the implantable cardioverter defibrillator from a first mode to a second mode. A processor is disposed within the housing in electrical communication with the communication interface. The processor is configured to switch the implantable cardioverter defibrillator between the first and second modes. A battery is disposed within the ICD housing configured to convert chemical energy into electrical energy at a relatively low DC voltage. A DC to AC converter is disposed within the housing electrically coupled to the battery and configured to convert the low DC voltage to a low AC voltage. A transformer is disposed within the housing electrically coupled to the converter configured to convert the low AC voltage to a high AC voltage. A rectifier is disposed within the housing electrically coupled to the transformer and configured to convert the high AC voltage to a high DC voltage. An energy storage capacitor, which is used to store and deliver the necessary defibrillation energy, is disposed within the housing electrically coupled to the rectifier, wherein the energy storage capacitor is configured to store the defi

Problems solved by technology

These strong electromagnetic fields produced by MRI systems can cause problems for implantable medical devices and as a result, both the U.S. Food and Drug Administration (FDA) and many pacemaker manufacturers have issued warnings against pacemaker recipients undergoing MRIs.

More specifically, it has been documented that implantable cardioverter defibrillators (ICDs) can exhibit a number of malfunctions when placed inside of a clinical MRI scanner bore.

In the presence of the main static B0 field of the MR scanner, these ferrite or iron materials saturate and become very inefficient.

It has been documented, that the charging transformer of an ICD will saturate

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