7
Figure 3. Ongoing Management of SVT of
Unknown Mechanism
Regular SVT
Pre-excitation
present in sinus
rhythm
YES
NO
If
ineffective
EP study and
catheter ablation
(Class I)
Ablation
candidate, willing to
undergo ablation
Ablation
candidate, pt
prefers ablation
YES NO YES NO
Medical therapy
a
If
ineffective
EP study and
catheter ablation
(Class I)
Beta blockers,
diltiazem, or
verapamil
(in the absence
of pre-excitation)
(Class I)
Flecainide or
propafenone
(in the absence
of SHD)
(Class IIa)
Amiodarone,
dofetilide, or
sotalol
(Class IIb)
Digoxin
(in the
absence of
pre-excitation)
(Class IIb)
Drug options
a
Clinical follow-up without treatment is also an option.
