XXXX : electrophysiologic and antiarrhythmic properties in refractory @entity1165 .

@entity1 @entity712 @entity1165 @entity6237 @entity2224 @entity453 @entity943 @entity1168
Twenty-two @entity1 with @entity453 and spontaneous @entity1165 ( @entity1165 ) or @entity2224 ( @entity2224 ) underwent intracardiac electrophysiologic evaluation and, when possible, ambulatory monitoring before and after therapy with @entity6237 (mean dose 418 +/- 87 mg [mean +/- standard deviation]). An average of 4 antiarrhythmic agents were used and were unsuccessful before therapy with @entity6237 was begun. During 64 +/- 16 hours of control Holter monitoring in 16 @entity1 , all had 1 or more salvos of @entity1165 , as well as ventricular premature complexes (VPCs). Programmed stimulation during the control period induced @entity1165 in 17 of 22 @entity1 . After @entity6237 therapy, Holter monitoring showed elimination of all forms of @entity1165 in all but 1 @entity1 , as well as significant reduction of paired VPCs by 95% (p less than 0.03) and single VPCs by 70% (p less than 0.005). Electrophysiologic study during @entity6237 therapy showed significant increases in AH, HV, PR, QRS and QTc intervals, and the ventricular effective refractory period. Programmed stimulation in 17 @entity1 taking @entity6237 , with a mean plasma level of 1,075 +/- 521 ng/ml, showed ablation of inducible @entity1165 in only 2 @entity1 , a worsening in 5 and continued @entity1165 inducibility in 10. Adverse effects that required drug withdrawal were infrequent and encountered in @entity1 who received higher drug levels: 1 @entity1 with @entity712 and 1 with severe sinus @entity1168 . Thus, although @entity6237 suppresses complex ventricular @entity943 on Holter recordings, it rarely alters the response to programmed stimulation. Caution is recommended in its use for recurrent sustained @entity1165 or @entity2224 and in the interpretation of electrophysiologic studies until the predictive value of programmed stimulation with @entity6237 therapy is established.
