Chapter 3 ST-Elevation Myocardial Infarctiona. Amiodarone: 150 mg infused over 10 minutes
(alternative dose 5 mg/kg); repeat 150 mg every
10 to 15 minutes as needed. Alternative infusion:
360 mg over 6 hours (1 mg/min), then 540 mg
over the next 18 hours (0.5 mg/min). The total
cumulative dose, including additional doses given
during cardiac arrest, must not exceed 2.2 g over
24 hours. (Level of Evidence: B)
b. Synchronized electrical cardioversion starting
at monophasic energies of 50 J (brief anesthesia is
necessary). (Level of Evidence: B)Class IIa
It is reasonable to manage refractory polymorphic
VT by:
a. Aggressive attempts to reduce myocardial isch-
emia and adrenergic stimulation, including thera-
pies such as beta-adrenoceptor blockade, IABP
use, and consideration of emergency PCI/CABG
surgery. (Level of Evidence: B)
b. Aggressive normalization of serum potassium
to greater than 4.0 mEq/L and of magnesium to
greater than 2.0 mg/dL. (Level of Evidence: C)
c. If the patient has bradycardia to a rate less than
60 beats per minute or long QTc, temporary
pacing at a higher rate may be instituted. (Level of
Evidence: C)Class IIb
It may be useful to treat sustained monomorphic VT
not associated with angina, pulmonary edema, or
hypotension (blood pressure less than 90 mm Hg)
with a procainamide bolus and infusion. (Level of
Evidence: C)
Class III
1 The routine use of prophylactic antiarrhythmic
drugs (i.e., lidocaine) is not indicated for suppres-
sion of isolated ventricular premature beats, cou-
plets, runs of accelerated idioventricular rhythm, or
nonsustained VT. (Level of Evidence: B)
2 The routine use of prophylactic antiarrhythmic
therapy is not indicated when fi brinolytic agents are
administered. (Level of Evidence: B)
c. Ventricular premature beats
Class III
Treatment of isolated ventricular premature beats,
couplets, and nonsustained VT is not recommended
unless they lead to hemodynamic compromise.
(Level of Evidence: A)d. Accelerated idioventricular rhythms and
accelerated junctional rhythms
Class III
1 Antiarrhythmic therapy is not indicated for accel-
erated idioventricular rhythm. (Level of Evidence:
C)
2 Antiarrhythmic therapy is not indicated for accel-
erated junctional rhythm. (Level of Evidence: C)e. Implantable cardioverter defi brillator
implantation in patients after STEMI
See Figure 3.6.
The following information from the ACC/AHA/
ESC 2006 Guidelines for Management of Patients
with Ventricular Arrhythmias and the Prevention of
Sudden Cardiac Death (VA & SCD) [16] is relevant
to patients with STEMI. Therefore, selected recom-
mendations from the 2004 STEMI Guidelines noted
below have been updated for consistence with the
VA & SCD Guidelines.
Recommendations for prophylactic ICD implanta-
tion based on ejection fractions (EFs) have been
inconsistent because clinical investigators have chosen
different EFs for enrollment in trials of therapy,
average values of the EF in such trials have been sub-
stantially lower than the cutoff value for enrollment,Fig. 3.6 Algorithm for selection of patients for implantation of an
implantable cardioverter defi brillator (ICD) for primary prevention of
sudden cardiac death after STEMI. Adapted from recommendations
in ACC/AHA/ESC 2006 Guidelines for Management of Patients With
Ventricular Arrhythmias and Prevention of Sudden Cardiac Death,
Circulation. 2006;114:e385.