Methods and implantable medical systems that implement exposure modes of therapy that allow for continued operation during exposure to a magnetic disturbance

A method of controlling an exposure mode of therapy of an implantable medical device, comprising:

• determining a device type of the implantable medical device;
• upon detecting a need to switch to the exposure mode, selecting the exposure mode of therapy of the implantable medical device based on the device type and a pre-exposure mode of therapy;
• and
• implementing the exposure mode of therapy at the implantable medical device, wherein determining the type of implantable medical device comprises determining whether the implantable medical device is a type capable of providing a defibrillation therapy and when the implantable medical device is not a type capable of providing defibrillation therapy, then selecting the exposure mode based on device type and the pre-exposure mode comprises implementing a pacing mode that paces a same set of chambers of the heart as the pre-exposure mode.

A method of controlling an exposure mode of therapy of an implantable medical device, comprising:

• determining a device type of the implantable medical device;
• upon detecting a need to switch to the exposure mode, selecting the exposure mode of therapy of the implantable medical device based on the device type and a pre-exposure mode of therapy;
• and
• implementing the exposure mode of therapy at the implantable medical device, wherein prior to implementing the exposure mode of therapy there are pre-exposure rates of cardiac activity and wherein the exposure mode of therapy includes providing pacing from the implantable medical device, the method further comprising:
• upon detecting a need to switch to the exposure mode, selecting an exposure mode pacing rate based on the pre-exposure rates;
• and
• implementing the exposure mode pacing rate at the implantable medical device while implementing the exposure mode of therapy.