Exercise-Induced Double (Atria1 and Ventricular) Report of Three Cases Tachycardia: A

Summary. Two important features of our three cases deserve emphasis. 1) Exercise-induced double tachycardia may simulate polymorphic ventricular tachycardia and esophageal ECG studies may help in differentiation. 2) Abnormal automaticity or triggered foci may reside in both the atrium and the ventricle and produce double tachycar- dias. Beta-blocker therapy was effective in preventing exer- cise-induced tachycardia in one case but produced intolera- ble side effects in a second case. References 1. Castellanos A Jr, Azan L. Calvin0 JM. Simultaneous tachycardias. Am Heart J 1968$9:3x8-73, 2. Wishner SH. Kastor JA, Yurchak PM. Double atria1 and atrioventricular junctional tachycardia. N Engl J Med 1972;287:552-3. 3. Belhassen B, Pelleg A, Paredes A, Laniado S. Simultaneous AV nodal reentrant and ventricular tachycardias. PACE 1984:7:325-3 I. 4. Bellorini M, Chouty F, Boulet E. et al. Un cas de bitachycardie catecholergique severe. Ann Cardiol Angeiol (Paris) 1986;35: 159-62. 5. Benson DW Jr, Gallagher JJ. Sterba R, Klein GJ, Armstrong BE. Catecholamine induced double tachycardia: case report in a child. PACE 1980:3:96103. 6. Motte G, Sebag C. Belhassen B. Welti JJ. Les bitachycardies. Arch Mal