Medtronic LNQ22 MRI Technical Manual

LINQ II™ LNQ22

Insertable Cardiac Monitor

MRI procedural information

MRI Technical Manual

Caution: Federal law (USA) restricts this device to sale by or on the order of a physician.

The following list includes trademarks or registered trademarks of Medtronic in the United States and
possibly in other countries. All other trademarks are the property of their respective owners.

LINQ II, Medtronic, Reveal, Reveal LINQ

Contents

1 Introduction 4

2 MRI conditions for use 4

3 Potential adverse events 4

4 Cardiology responsibilities before and after the MRI scan 4

5 Radiology requirements 5

6 Potential effects during an MRI scan 6

7 Following the MRI scan 6

3

1 Introduction

The Medtronic LINQ II Model LNQ22 Insertable Cardiac Monitor (ICM) is an MR Conditional device and, as such,
is designed to allow patients to be safely scanned by a magnetic resonance imaging (MRI) machine. Preclinical
testing has demonstrated that the LINQ II device is safe for use in the MRI environment when used according to
the MRI conditions for use. Before performing an MRI scan on a patient that has an implanted LINQ II device, the
radiology and cardiology staff involved in the procedure should understand the requirements and instructions in
this manual. For non-MRI related instructions for use for a LINQ II device, such as the implant procedure and
programming instructions, cardiologists should refer to the LINQ II ICM Clinician Manual.

2 MRI conditions for use

The LINQ II device is MR Conditional and, as such, is designed to allow patients to be safely scanned by an MRI
machine when used according to specified MRI conditions for use. The MR Conditional symbol shown below is
used to indicate the conditional safety of devices and components in the MR environment.

MR Conditional symbol

A patient with a LINQ II device can be safely scanned in an MR system that meets the following conditions. Failure
to follow these conditions for use may result in a hazard to the patient during an MRI scan:

●

The static magnetic field must be 1.5 T or 3.0 T.

●

The MRI equipment must be a horizontal-field, cylindrical-bore, clinical system for hydrogen proton imaging.

●

The maximum spatial field gradient of the static magnetic field must be ≤25 T/m (2500 gauss/cm).

●

The gradient slew rate of whole-body gradient systems must be ≤200 T/m/s per axis.

●

The whole-body specific absorption rate (WB-SAR) as reported by the MRI equipment must be ≤4.0 W/kg.

●

The head SAR as reported by the MRI equipment must be ≤3.2 W/kg.

●

There are no restrictions on the placement of receive-only coils.

●

There are no restrictions on the use of local transmit-and-receive coils for MRI scanning of the head or the
extremities.

Do not bring the tablet that the Reveal LINQ Mobile Manager clinician app is installed on, the Patient Assistant, or
the patient monitor into Zone 4 (MRI magnet room), as defined by the American College of Radiology. They are MR
Unsafe.

3 Potential adverse events

There are no known potential adverse events for MRI scans performed on LINQ II patients when the conditions in
Chapter 2 are followed.

4 Cardiology responsibilities before and after the MRI scan

Before the MRI scan – Before a radiologist performs an MRI scan on a LINQ II device patient, the cardiology staff

should ensure the patient record contains all relevant information about any implanted devices, such as model
name, model number, and serial number.

4

The patient records must be complete and accurate because the radiology staff uses the records to verify the
following important information:

●

That the patient has a LINQ II device

●

That the patient has no other devices, leads, or implanted items that are known to pose a hazard in an MR
environment.

It is acceptable to scan patients who have multiple MR Conditional devices, as long as the MR labeling conditions
for all implants are satisfied.

It is acceptable to scan patients who have LINQ II devices that have been abandoned if the MRI conditions for use
are satisfied.

After the MRI scan – After a radiologist performs the MRI scan, an optional step for the cardiology clinician is to
review the patient’s data for episodes that may have been inappropriately collected during the MRI scan. Collect
the data using any of the device interrogation methods available for the LINQ II device. This can be completed at
the clinician’s convenience.

5 Radiology requirements

Before the patient receives an MRI scan, the radiology staff should take the following actions:

●

Ensure that the MRI equipment meets all requirements specified in Chapter 2, “MRI conditions for use”,
page 4.

●

Ensure that the pre-scan cardiology responsibilities have been performed (for more information, see
Chapter 4, “Cardiology responsibilities before and after the MRI scan”, page 4).

●

Verify the following important information:
– That the patient has a LINQ II device
– That the patient has no other devices, leads, or implanted items that are known to pose a hazard in an MR

environment.

It is acceptable to scan patients who have multiple MR Conditional devices, as long as the MR labeling conditions
for all implants are satisfied.

It is acceptable to scan patients who have LINQ II devices that have been abandoned if the MRI conditions for use
are satisfied.

If you have questions about whether the patient should receive an MRI scan, contact the patient’s cardiologist. The
cardiologist may need to contact Medtronic for guidance.

You can use an x-ray image of the LINQ II device, such as shown in Figure 1, to identify that the patient has a LINQ II
device. LINQ II devices are typically implanted in the left chest area.

5

Figure 1. Front and side view x-ray images of an implanted LINQ II device

6 Potential effects during an MRI scan

The LINQ II device design and the MRI conditions for use (described in Chapter 2) limit potential effects during an
MRI scan to the following. Such effects will not harm the patient or damage the device.

MRI interactions – Due to the static magnetic field and gradient magnetic fields produced by MRI equipment, the
magnetic material of an implanted device may exert force, vibration, and torque effects that the patient may or may
not feel. The MRI scan may induce currents and voltages in the device, which could lead to tissue heating, nerve
stimulation, and electrical stress on device components.

Image artifact and distortion – Image artifact and distortion can result from the presence of the LINQ II device
within the field of view. Image artifact and distortion resulting from the presence of the device within the field of view
must be considered when selecting the field of view and imaging parameters. These factors must also be
considered when interpreting the MRI images.

False detection and data corruption – The MRI scan may impact the sensing circuitry of the LINQ II device
which may corrupt the recorded data in the device or could cause false event detection and recording of
inappropriate data.

7 Following the MRI scan

The radiology and cardiology staff should ensure that the post-scan cardiology responsibilities described
previously in this manual are performed.

6

Medtronic, Inc.

*M974772A001*

710 Medtronic Parkway
Minneapolis, MN 55432
USA
www.medtronic.com
[phone]

Medtronic USA, Inc.

Toll-free in the USA (24-hour technical
consultation for physicians and medical
professionals)
Bradycardia: [phone]
Tachycardia: [phone]

Technical manuals

www.medtronic.com/manuals

© 2019 Medtronic
M974772A001 A
2019-01-30