CONTINUATION OF ANTIARRHYTHMIC DRUGS, OR ARRHYTHMIA SURGERY AFTER MULTIPLE-DRUG FAILURES - A RANDOMIZED TRIAL IN THE TREATMENT OF POSTINFARCTION VENTRICULAR-TACHYCARDIA
Nm. Vanhemel et al., CONTINUATION OF ANTIARRHYTHMIC DRUGS, OR ARRHYTHMIA SURGERY AFTER MULTIPLE-DRUG FAILURES - A RANDOMIZED TRIAL IN THE TREATMENT OF POSTINFARCTION VENTRICULAR-TACHYCARDIA, European heart journal, 17(4), 1996, pp. 564-573
Background In patients with postinfarction sustained ventricular tachy
cardia showing one or more antiarrhythmic drug failures, the question
is how long to proceed with new drug trials before deciding to perform
map-guided arrhythmia surgery. Although the techniques of this surger
y developed rapidly in the early 1980s, this therapy may be offset by
damage to residual left ventricular function. However, surgery has bee
n shown to be very effective in selected groups of patients. Methods A
randomized study was carried out in patients with postinfarction vent
ricular tachycardia and eligible for arrhythmia surgery based on resid
ual left ventricular function. Therapy failure was defined by the occu
rrence of the following events: spontaneous recurrence of ventricular
tachycardia or ventricular fibrillation, sudden cardiac death, inducib
ility of sustained ventricular tachycardia or ventricular fibrillation
with programmed stimulation of the heart, symptomatic non-sustained v
entricular tachycardia requiring therapy or side-effects of antiarrhyt
hmic drugs requiring withdrawal. In the drug limb, failure of the firs
t antiarrhythmic drug was accepted but failure of a second and differe
nt drug was regarded as true therapy failure. Results After randomizat
ion, antiarrhythmic drug therapy was administered in 33 patients, and
30 patients underwent surgery. Neither group differed in baseline char
acteristics, and the mean number of drug failures before randomization
was 2.7. The Kaplan-Meier therapeutic failure of antiarrhythmic drugs
was 39 +/- 11%, 42 +/- 11% and 51 +/- 18% at 0.5-, 1- and 4-year foll
ow-up, respectively, whereas the therapeutic failure of cardiac surger
y was 37 +/- 11%, 37 +/- 11% and 50 +/- 20% at 0.5, 1 and 4 years, res
pectively, showing no statistical difference. The 1- and 4-year Kaplan
-Meier survival of the antiarrhythmic drug-treated group was 91 +/- 6%
and 78 +/- 15%, respectively, and of the surgical group 92 +/- 6% and
59 +/- 20%, respectively, and did not differ between either group. Ho
wever, the relative risk for total cardiac death was higher in the sur
gical limb than in the drug limb (relative risk 2.2, CI 0.68-7.48). Co
nclusion This study demonstrated no difference between the therapeutic
result of continuation of two different antiarrhythmic drugs and that
of arrhythmia surgery. Despite the small number of patients studied,
it is recommended that drug therapy should continue as long as this re
gimen is tolerated by the patient. When true drug refractoriness or si
de-effects of drugs arise, arrhythmia surgery offers a valuable altern
ative. However, when additional reasons for cardiac surgery exist, arr
hythmia surgery should be undertaken earlier and may become the first
choice of treatment of postinfarction ventricular tachycardia.