We performed transesophageal electric cardiac stimulation procedures (TEECS) in order to restore sinus rhythm in 92 patients with non-valvular isolated atrial flutter (AF) on background of CAD (n=75) and
myocardiofibrosis (n=17) with ECG FF interval within 260–279 ms. Arterial hypertension was diagnosed in 67 (72.8 %) patients. Mean arrhythmia anamnesis constituted 4.5 years with mean arrhythmia duration of 47.6±7.5
days. For evaluation of preliminary antiarrhythmic therapy (AAT) influence upon procedure efficacy all patients were divided into two groups: group 1 (n=59) – cardioversion was performed with concomitant AAT; group 2
(n=33) – ААТ wasn’t administered. In group 1 patients were administered amiodaron (49.2 %) and its combinations with other antiarrhythmic agents (AAA) (28.8 %), AAA of class I according to Vaughan-Williams
(13.6 %) and their combinations with atrioventricular conduction blockers (8.5 %). We found significant decrease of TEECS efficacy in group 1 patients with AAT background (86.4 % vs. 100 % in group 2, Р=0.03),
which is explained by proarrhythmogenic effect of AAA: sinus rhythm restoration was through atrial fibrillation periods (Р=0.01), recurrent procedures were needed more often (Р=0.03), higher doses of procainamide were
needed for poststimulation atrial fibrillation treatment (Р<0.05), while TEECS efficacy increased after lowering doses or termination of AAA.