SYNDROME DE WOLFF PARKINSON WHITE PATENT OU INAPPARENT ASSOCIE A UNE DUALITE DE CONDUCTION NODALE. A PROPOS DE 4 OBSERVATIONS

In a series of 48 patients undergoing electrophysiological investigation for attacks of reciprocating tachycardia related to concealed or overt Wolff-Parkinson-White syndrome in sinus rhythm, 4 patients were found to have duality of nodal conduction. This association was responsible for several tachycardia circuits: in 2 patients the activation passed constantly retrogradely through the accessory pathway and then either through the slow nodal pathway or the rapid nodal pathway in the anterograde direction. In the other 2 patients, in addition to classical orthodromic tachycardia, purely intranodal reciprocating rhythms giving rise to sustained tachycardia in 1 case and to simple echoes in the other, were observed.