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

摘要

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.

主权项

1. A method of performing a magnetic resonance imaging (MRI) scan on a patient having an implanted cardioverter defibrillator (ICD), comprising the steps of:
determining that the ICD comprises a ferrite core high voltage power supply transformer; with the ICD not being in the presence of an MRI field generated by an MRI scanner, sending a communication signal from an external programmer to the ICD, the communication signal being a command to precharge an energy storage capacitor of the ICD before the patient undergoes an MRI scan, the command also switching the ICD into an MRI mode, where the MRI mode is configured to autonomously detect a dangerous ventricular arrhythmia and when needed deliver a precharged defibrillation shock; moving the patient into the MRI scanner; performing the MRI scan; removing the patient from the MRI scanner after the MRI scan is completed or after the ICD delivers a first defibrillation shock to the patient while in the presence of the MRI field; moving the patient substantially away from the MRI field; and determining that the ICD has not delivered the first defibrillation shock and allowing the ICD to automatically bleed off a first electrical charge stored in the energy storage capacitor, or if the ICD has delivered the first defibrillation shock and it is determined that additional therapy is needed, allowing the ICD to recharge the energy storage capacitor and deliver a second defibrillation shock to the patient.