Electrophysiological properties of the atrioventricular node and ageing: evidence of a lower incidence of dual nodal pathways in the elderly

Aims The purpose of this study was to investigate the relationship between the incidence of dual atrioventricular (AV) nodal pathways and age. Age-rel ated changes in the AV node electrophysiological properties have rarely bee n investigated. AV nodal re-entrant tachycardia is more frequent in the you ng than in the elderly. Methods and Results From 1988 to 1998, premature atrial stimulation was per formed in 1435 patients referred to our institution for transoesophageal el ectrophysiological study. 1276 patients (89%) with a diagnosis of ventricul ar pre-excitation, supraventricular arrhythmia or AV block were excluded. T he study cohort consisted of the remaining 159 patients (11% of the whole g roup) referred for syncope (8(.)2% of the subgroup), suspected ventricular pre-excitation (10(.)7%), suspected sinus node dysfunction (52(.)8%) or und etermined palpitations (28(.)3%). The 159 study patients were divided into 3 groups according to age: group A (11-30 years, 50 patients), group B (30- 60 years, 35 patients) and group C (> 60 years, 74 patients). A dual AV nod al pathway was found in 16 patients of group A (32(.)0%), 6 patients of gro up B (17(.)1%) and 8 patients of group C (10(.)8%), the difference between group A and group C being significant (P <0(.)05). Conclusion The incidence of dual AV nodal pathways decreases with ageing, s uggesting that the AV node undergoes age-related electrophysiological chang es. This finding could explain the uncommon onset of AV nodal re-entrant ta chycardia in the elderly. (C) 2000 The European Society of Cardiology.