[The effect of pacing protocol and beta-blockers on the results of serial drug testing in sustained ventricular tachycardia].
Serial drug testing (SDT) using programmed electrical stimulation (PES) and a downgraded pacing protocol was performed in 56 patients with sustained ventricular tachycardia (S-VT) of various aetiology. SDT was carried out during oral antiarrhythmic therapy alone or in combination with beta-blockers. The pacing protocol's reduced aggressiveness consisted in prolonging minimal coupling intervals of the third extrastimulus and in milder criteria employed in evaluating the drug in PES and in cases of recurrent S-VT (an S-VT with a heart rate below 150 considered a positive effect of the tested drug). All patients were followed up during the therapy chosen on the basis of SDT for an average 19.7 +/- 19.4 months. SDT led to the identification of an effective therapy in 48 patients (86%, group A). No effective therapy was found for the remaining eight patients (14%, group B). There were no significant differences between both groups in age, sex, representation of individual cardiopathies, the frequency of spontaneous S-VT or ejection fraction. Using Kaplan-Maier's survival curves, the incidence of arrhythmia events (defined as a recurrence of S-VT or sudden death), cardiac death or any death was significantly higher in group B. PES was used to test a total of 202 drugs or their combinations; of this number, S-VT induction failed in 90 (45%). No significant difference in the efficacy of antiarrhythmics was found to be related to whether they had been used alone (44%) or in combination (49%, p > 0.05). Beta-blockers likewise had no effect on the incidence of arrhythmia events during follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)
Lukl
J
J
I. interní klinika Fakultní nemocnice, Olomouc, Ceská republika.
Heinc
P
P
Cíhalík
C
C
Fiala
M
M
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D002304:Cardiac Pacing, Artificial; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017180:Tachycardia, Ventricular / Q000188:drug therapy* / Q000503:physiopathology
D000319:Adrenergic beta-Antagonists; D000889:Anti-Arrhythmia Agents
Vliv stimulacního protokolu a beta-blokátorů na výsledky sériového testování léků u setrvalé komorové tachykardie.