INTRACORONARY INFUSION OF DILUTE ETHANOL FOR CONTROL OF VENTRICULAR RATE IN PATIENTS WITH ATRIAL-FIBRILLATION

The effects of selective infusion of 25% ethanol into the AV nodal art ery was assessed in 11 patients with atrial fibrillation and uncontrol lably rapid ventricular response rates. The primary study objective wa s to achieve permanent modification of AV nodal function and control v entricular rate without drug therapy and without causing permanent com plete AV block. ''Clinical success'' was defined as drug-free rate con trol by either AV nodal modification or the production of complete AV block. Selective catheterization and ethanol infusion into the AV noda l artery could be performed in nine patients. Intracoronary ethanol in fusion acutely caused second- or third-degree AV nodal block in seven patients and an increase in AV nodal refractory period and Wenckebach cycle length in two patients. Acute occlusion of the AV nodal artery o r infarction of nontarget myocardium was not observed. During follow-u p of 22.2 +/- 2.2 months the primary study objective was attained in o nly four of nine patients treated, yielding an efficacy of 44%. Howeve r, the ''clinical success'' rate was 78%. The acute effects of ethanol on AV conduction did not predict the chronic effects. Selective intra coronary infusion of dilute ethanol to control the ventricular rate in atrial fibrillation should be considered when radiofrequency ablation has been unsuccessful. This method of chemical ablation is as effecti ve and probably safer than rapid administration of 96% ethanol.