[Evaluation of typical atrial flutter cycle duration during electric stimulation cardioversion]

We performed 225 transesophageal electric cardiac stimulation (TEECS) procedures in order to restore sinus rhythm in patients with atrial flutter (AF) and ischemic heart disease (IHD) (n = 161) and postmyocarditic cardiosclerosis (n = 64). Mean duration of history of arrhythmia was 7.1 years, mean duration of present arrhythmic episode was 25.3 +/- 3.6 days. No antiarrhythmic therapy (AAT) was used before TEECS. Depending on AF cycle duration all patients were divided into 3 groups: group 1 (n = 75)--below 220 ms, group 2 (n = 108)--220-259 ms, and group 3 (n = 42)-- > or = 260 ms. Significant direct relation was found between AF cycle duration and patient's age, IHD progression, heart conduction abnormalities, chronic pulmonary pathology and decrease of TEECS efficacy. In patients with AF cycle duration below 220 ms procainamide was significantly more often used during TEECS, therefore, in such patients preliminary AAT makes more sense before TEECS. At the same time in patients with AF cycle duration above 260 ms AAT increased risk of proarrhythmia. Therefore AAT (with medications with short half-life [Class I by Vaughan-Williams]) will be more useful and safe after stimulation transformation of AF into atrial fibrillation.