Grosu AA, Shevchenko NM, Zhosan SI, Tsurkan SE, Testemitsanu AN. Ter Arkh 1989;61(4):75-8. A study was made of the clinical importance of atrial fibrillation-flutter (AFF) induced by using different modes of left atrium stimulation via the esophagus. Ninety-eight patients were entered into the study including 40 patients with a history of AFF paroxysms, 24 with risk factors of AFF development, and 27 practically normal persons. The stimulation modes applied permitted reproducing stable paroxysms of AFF in 85 percent of the patients with a history of arrhythmias and in none of the normal persons. As for the patients with risk factors, stable paroxysms of AFF could be induced in 33 percent of the cases. The specificity and sensitivity of transesophageal electrophysiologic stimulation (TEES) with the modes applied were 100 and 82 percent, respectively. The investigations have demonstrated that TEES appeared most effective when applied in the mode of an even increase of the frequency of the set pace up to 300 imp/min.