Morphmatch

Question 1

Can Morphmatch be used in atrial based detection?

Answer 1

No ventricular detection only

Question 2

Is morphmatch compatible with SMART

Answer 2

No - SMART must be off

Question 3

What two algorithms must be satisfied before morphmatch kicks in

Answer 3

Onset and Stability

Question 4

What is the purpose of Morphmatch

Answer 4

To distinguish SVT from VT

Question 5

Is it available in HF CRT devices?

Answer 5

Yes - but only if LV sensing is off

Question 6

Why must LV sensing be off for morphmatch to work

Answer 6

Because template is rolling - thus need constant intrinsic. Which reduces CRT pacing. Not like wavelet

Question 7

Morphmatch is available in which zone

Answer 7

VT1 and VT2

Question 8

3 ways it distinguishes morphology

Answer 8

Maximum Spike

Area

Vector

Question 9

How many beats to build a template and what beats don’t count

Answer 9

32

Anything over 100bpm and ectopics

Question 10

When is morphology reset

Answer 10

Daily // After reprogramming // Tachy Rx or periods of excessive variation

Question 11

What is the morphology sampling rate

Answer 11

128hz (8ms)

Question 12

What is the nominal SVT detection and can this be programmed

Answer 12

No programming - Double VT counter

Question 13

If there is 1 unstable beat - how much does morphmatch drop the detection counter?

Answer 13

By 20 - old devices used to start over again

Question 14

Morphmatch limitations

Answer 14

Only for initial detection
Rate dependent BBB will throw it
Paced rhythm - can’t initialised
Cant be used with SMART

Question 15

What are the 3 thresholds for morphmatch and their values

Answer 15

Low = 28 (More sensitive)

Std = 36

High = 42 (More specific)

Question 16

Morph counter must be below what % of VT counter to be classified as SVT

Answer 16

50%