MRI

Question 1

What are the hazards to the device related to the Static magnetic fields?

Answer 1

• force and torque (pt discomfort and dislodgement)
• vibration (pt discomfort and device damage)
• device interactions (may inhibit/cause therapy)

Question 2

What are the hazards to the device related to the Gradient magnetic fields?

Answer 2

• unintended stimulation (arrhythmia induction)
• vibration (pt discomfort and device damage)
• case heating (pt discomfort, necrosis)
• device interactions (may inhibit/cause therapy)

Question 3

What are the hazards to the device related to the RF magnetic fields?

Answer 3

• unintended stimulation (arrhythmia induction)
• case heating (pt discomfort, necrosis)
• device interactions (may inhibit/cause therapy)
• lead electrode heating

Question 4

Which type(s) of magnetic fields can cause unintended stimulation (arrhythmia induction)?

Answer 4

gradient and RF

Question 5

Which type(s) of magnetic fields can cause vibrations leading to patient discomfort and possible device damage?

Answer 5

static and gradient

Question 6

Which type(s) of magnetic fields can cause the case to heat resulting in possible patient discomfort and tissue necrosis?

Answer 6

gradient and RF

Question 7

Which type(s) of magnetic fields can cause lead electrode heating that may negatively impact the delivery of therapy and proper sensing/threshold capture?

Answer 7

RF

Question 8

Which label given to items that pose no known hazards resulting from exposure to any MRI environment?

Answer 8

MR Safe

Question 9

Which label is given to items which pose unacceptable risks to the patient, medical staff, or other persons within the MRI environment?

Answer 9

MR Unsafe

Question 10

Which label is given to items with demonstrated safety in the MRI environment within defined conditions?

Answer 10

MR Conditional

Question 11

What device settings/values will prevent MRI SureScan mode from being turned on?

Answer 11

• if pacing impedances are < 200 or 1500 <
• if defib lead impedances are < 20 or 200 <
• if RRT/ERI/EOS has been reached

Question 12

Which pin plug is approved as MR Conditional with the CRT MRI system?

Answer 12

the 6725 atrial pin plug

Question 13

What is the MRI SureScan timeout value for all ICD’s and CRT systems?

Answer 13

6hrs

Question 14

What is the MRI SureScan timeout value for all pacemaker systems?

Answer 14

24hrs

Question 15

What is the recommended RV pacing capture threshold value for PM-dependent patients going for an MRI?

Answer 15

< 2.0V at 0.4ms