The influence of atrioventricular and atrioventricular nodal re-entrant tachycardia on left ventricular systolic and diastolic function

Abstract

Background: Incessant tachycardia may result in left ventricular (LV) systolic dysfunction. Little is known about the influence of atrioventricular tachycardia (AVRT) and atrioventricular nodal re-entrant tachycardia (AVNRT) on LV systolic and diastolic function. The aim of the study was to assess LV systolic and diastolic function and factors affecting LV systolic and diastolic performance in patients with AVRT and AVNRT.
Material: The study group included 90 patients (40 male, 50 female, mean age 40 ± 12 years) with symptomatic narrow-QRS tachycardia. After an invasive electrophysiology study (EPS) had been performed, these were divided into two groups: one (AVNRT) of 25 patients with AVNRT and the other (WPW) of 65 patients with AVRT. The control group consisted of 50 healthy volunteers (23 male, 27 female, mean age 39 ± 13 years). In all three groups transthoracic echocardiography was performed in order to assess LV systolic and diastolic function.
Results: LV fractional shortening (FS) (WPW: 32 ± 6%, AVNRT: 36 ± 4%, p < 0.005) and ejection fraction (EF) (WPW: 54 ± 7%, AVNRT: 55 ± 5%, p < 0.001) were significantly decreased in the study groups compared to the control group (FS: 40 ± 5%, EF: 62 ± 4%). FS was significantly increased in the AVNRT compared to the WPW patients (p < 0.005). LV diastolic dysfunction was found in 20 (80%) of the AVNRT and 55 (83%) of the WPW group and in none of the patients from the control group. A positive correlation was found between diastolic dysfunction and the scale of recurrence of AVRT (R = 0.67, p < 0.05) and AVNRT (R = 0.52, p < 0.05).
Conclusions: AVNRT and AVRT may lead to development of LV systolic and diastolic dysfunction. LV diastolic dysfunction is related to the frequency of AVRT or AVNRT recurrence. (Cardiol J 2007; 14: 160-166)