A multicentre, double-blind randomized crossover comparative study on the efficacy and safety of dofetilide vs sotalol in patients with inducible sustained ventricular tachycardia and ischaemic heart disease

Background Antiarrhythmic drugs are still used for the treatment of ventric ular tachyarrhythmias. in combination with implantable cardioverter-defibri llators or without them. Aim of the study In a double-blind randomized crossover design, the short- and long-term efficacy and safety of oral dofetilide or oral sotalol were c ompared in 135 patients with ischaemic heart disease and inducible sustaine d ventricular tachycardia. Methods The inducibility of ventricular tachycardia was determined by progr ammed electrophysiological stimulation at baseline. Patients were then blin dly randomized to receive either oral dofetilide 500 mug twice daily or ora l sotalot 160 mg twice daily, for 3 to 5 days. Suppression of inducible ven tricular tachycardia on the drug was then assessed by programmed elect ro p hysiological stimulation. After a wash-out period of at least 2-5 days. the patients received the alternative treatment for 3 to 5 days. Suppression o f inducible ventricular tachycardia on the alternate drug was again determi ned by programmed electrophysiological stimulation. Selection of long-term treatment was allocated blindly according to programmed electrophysiologica l stimulation results. Results During the acute phase, 128 patients received both dofetilide and s otalol. Sixty-seven patients were responders to either drug. Forty-six pati ents (35(.)9%) were responders to dofetilide compared with 43 (33(.)6%) to sotalol (P=ns). Only 23 patients responded to both dofetilide and sotalol. Adverse events, deemed to be treatment related, were seen in 2(.)3% of pati ents receiving dofetilide and 8(.)6% of patients receiving sotalol (P=0(.)0 16). Three patients on dofetilide had torsade de pointes. Two patients rece iving sotalol died during the acute phase (one was arrhythmic death, and th e other was due to heart failure). During the long-term phase, two of 42 pa tients (4(.)8%) receiving dofetilide and three of 27 patients (11(.)1%) rec eiving sotalol withdrew from treatment due to lack of efficacy. Overall, du ring the long-term phase, 23(.)8% of the patients receiving dofetilide and 37(.)0% of the patients receiving sotalol. withdrew from treatment with a s imilar pattern of withdrawals for the two drugs. Conclusion Dofetilide was as efficacious as sotalol, in preventing the indu ction of sustained ventricular tachycardia. There was no concordance in the response rate in two-thirds of the patients. Dofetilide was significantly better tolerated during the acute phase than sotalol. Both dofetilide and s otalol were well tolerated during the long term with no statistically signi ficant difference in the adverse events.