A 14 year old with SVT

Baseline EP study• AH 60, HV 57, no preexcitation• Antegrade

• WCL 420• Decremental with AH jump at 600/390 + echos• Block with adenosine

• Retrograde• WCL 430• Decremental with VA jump at 600/420 + echos• Block with adenosine

• On isoproterenol, SVT #1 induced…

SVT #1

• All consistent with typical AVNRT• RF slow pathway modification…

Slow pathway area

AH 60 AH 50CS pacing 400 SVT 400

Spontaneous

340 340 340 340 340

Spontaneous

SVT #2

• Diagnosis? Next steps?• Attempt at 3D mapping for adjunctive clues…

Right posteroseptal

Slo

w p

ath

way

are

a

Inef

fect

ive

site

s ~

-60

ms

Ineffectiv

e sites

Slo

w p

ath

way

are

a

Thank you!

SVT #2 alone