Automatic junctional tachycardia in an adult.
We report an adult patient with junctional ectopic tachycardia, a condition which was initially described in infants, frequently in association with congenital defects. The patient had a rapid, irregular paroxysmal junctional tachycardia with a rate ranging from 160 to 220 beats/min, distinguishing it from the more common nonparoxysmal junctional tachycardia in which a slower heart rate is seen. The electrophysiological study performed during an episode of tachycardia demonstrated periods of atrioventricular dissociation and narrow QRS complexes as well as a junctional ectopic rhythm, which was suggested by a His deflection preceding each ventricular depolarization with a normal HV interval. Both the response to exercise and the results of atrial and ventricular stimulation suggested enhanced automaticity of a high junctional focus. Therapy combining procainamide, verapamil, and digitalis proved to be effective. Thus, junctional ectopic tachycardia can also occur in adults, probably due to enhancement of automaticity.
Kumagai
K
K
Second Department of Internal Medicine, Fukuoka University, School of Medicine, Japan.
Yamato
H
H
Yamanouchi
Y
Y
Matsuo
K
K
Tashiro
N
N
Hiroki
T
T
Arakawa
K
K
D000328:Adult; D004562:Electrocardiography; D004594:Electrophysiology; D006801:Humans; D008297:Male; D013613:Tachycardia, Ectopic Junctional / Q000503:physiopathology*