5
Table 2. Acute Treatment of SVT of Unknown Mechanism
COR
LOE Recommendations
I B-R Vagal maneuvers are recommended for acute treatment in
patients with regular SVT.
I B-R Adenosine is recommended for acute treatment in patients with
regular SVT.
I B-NR Synchronized cardioversion is recommended for acute treatment
in patients with hemodynamically unstable SVT when vagal
maneuvers or adenosine are ineffective or not feasible.
I B-NR Synchronized cardioversion is recommended for acute
treatment in patients with hemodynamically stable SVT when
pharmacological therapy is ineffective or contraindicated.
IIa B-R IV diltiazem or verapamil can be effective for acute treatment in
patients with hemodynamically stable SVT.
IIa C-LD IV beta blockers are reasonable for acute treatment in patients
with hemodynamically stable SVT.
Colors in tables and figures correspond to Class of Recommendation Table on pages 30-31.
Treatment
Figure 2. Acute Treatment of SVT of Unknown Mechanism
Regular SVT
Hemodynamically
stable
YES
NO
IV beta blockers, IV
diltiazem, or IV verapamil
(Class IIa)
Synchronized
cardioversion
a
(Class I)
If ineffective or not feasible
Synchronized cardioversion
a
(Class I)
a
For rhythms that break or recur
spontaneously, synchronized
cardioversion is not appropriate.
Vagal maneuvers and/or IV adenosine
(Class I)
If ineffective or not feasible
