189: Clinical and electrophysiological data of patients with first degree AV block and AV node reentrant tachycardia

Typical atrioventricular (AV) node re-entrant tachycardia (AVNRT) occurs in patients with dual AV nodal pathway, a rapid pathway used for retrograde conduction and a slow pathway used for the anterograde conduction. In sinus rhythm, the patients have generally the signs of conduction through the rapid pathway with a normal or short PR interval. The purpose of the study was to evaluate the prevalence of patients with 1st degree AV block and with AVNRT and their clinical characteristics.Methods973 patients, 348 males, 625 females, were admitted for typical AVNRT. They were aged from 6 to 90 years (mean age 50±19). Initial ECG and clinical data were collected. Electrophysiological study was systematic.ResultsSpontaneous 1st degree AV block (AVB) was rare and noted in 7 patients. The prevalence of the association 1st degree AV block and AVNRT was 0.7%. Five patients complained of AVNRT at exercise. Two patients had an ischemic heart disease. Patients with AVB were significantly older (71.5± 16 years) than patients without AVB (50±19)(p