Response to sotalol predicts the response to amiodarone during serial drug testing in patients with sustained ventricular tachycardia and coronary artery disease.
It was analyzed whether the response to sotalol can predict the response to amiodarone as evaluated by programmed ventricular stimulation in 30 patients with coronary artery disease and documented recurrent sustained ventricular tachycardia (VT). Programmed ventricular stimulation was performed using 1 or 2 extrastimuli during sinus rhythm and 4 drive cycle lengths at 2 right ventricular sites. If no ventricular tachyarrhythmia was induced, a third extrastimulus was introduced during a paced cycle length of 500 ms. During the control study, VT (mean cycle length 305 +/- 63 ms) was induced in all patients, and the right ventricular effective refractory period (during S1-S1 = 500 ms) was 223 +/- 12 ms. After sotalol, sustained and nonsustained VT were inducible in 22 (73%) and 7 (23%) patients, respectively. One patient did not undergo stimulation on sotalol, because of side effects. After amiodarone, sustained and nonsustained VT were inducible in 23 (77%) and 7 (23%) patients, respectively. The mean cycle length of the induced VT was prolonged after both drugs by 17% (p < 0.001). The effective refractory period was prolonged by 15% (p < 0.001) after sotalol and by 13% (p < 0.001 compared with baseline study; p = NS between both drugs) after amiodarone. Thus, concordant results (effective or ineffective drug) between sotalol and amiodarone were found in 26 patients (87%).


CONCLUSIONS
(1) The effects of sotalol and amiodarone on the cycle length of induced VT and on right ventricular effective refractory period were similar; and (2) inability to suppress VT by amiodarone can be predicted from the response to sotalol.(ABSTRACT TRUNCATED AT 250 WORDS)
Martínez-Rubio
A
A
Department of Cardiology and Angiology, University of Münster, Germany.
Shenasa
M
M
Chen
X
X
Wichter
T
T
Breithardt
G
G
Borggrefe
M
M
D000638:Amiodarone / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D005117:Cardiac Complexes, Premature / Q000503:physiopathology; D002304:Cardiac Pacing, Artificial; D015331:Cohort Studies; D003327:Coronary Disease / Q000150:complications*; D004341:Drug Evaluation; D004562:Electrocardiography / Q000187:drug effects; D005260:Female; D005544:Forecasting; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012032:Refractory Period, Electrophysiological / Q000187:drug effects; D013015:Sotalol / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D013318:Stroke Volume / Q000187:drug effects; D017180:Tachycardia, Ventricular / Q000150:complications* / Q000188:drug therapy* / Q000503:physiopathology; D016278:Ventricular Function, Right / Q000187:drug effects
D013015:Sotalol; D000638:Amiodarone