Electrophysiologic test in supine and upright position in patients with wolff parkinson white syndrome
Rosettani E.; Giusetto C.; Gaita F.; Mangiardi L.; Riccardi R.; Brusca A., 1987: Electrophysiologic test in supine and upright position in patients with wolff parkinson white syndrome. Giornale Italiano di Cardiologia 17(7): 569-574
It is well known that in patients with Wolff-Parkinson-White (W.P.W.) adrenergic activity stimulation induced by exercise or isoproterenol I.V. infusion shortens the anteroigrade effective refractory period (E.R.P.) of the accessory pathway. Our purpose was to evaluate whether the upright position produces similar changes on the electrophysiologic properties of the accessory pathway and influences reciprocating tachycardias induction. In 18 patients, with W.P.W. syndrome, who underwent electrophysiologic study, we determined the anterograde E.R.P. of the accessory pathway and attempted to induce a reciprocating tachycardia in the supine and in the supine and in the upright position. In 13 patients (72%) the anterograde E.R.P. of the accessory pathway shortened in the upright position (303 .+-. 104 msec vs 331 .+-. 123 msec; p < 0.001): in 4 patients (22%) it was unchanged; in 1 patient was not defined, being inferior to the atrium E.R.P. We were able to induce a reciprocating tachycardia in 3 patients in the supine position, in 6 patients in the upright position. Electrophysiologic testing in the upright position improves the evaluation of the accessory pathway electrophysiologic properties.