Influence of the treatment of the nodal reentrant tachycardia by RF catheter ablation on selected hemodynamic parameters of left ventricular systolic and diastolic function and exercise capacity

UNLABELLED: RF ablation is the most common non-pharmacological technique for the treatment of atrioventricular nodal reentry tachycardia (AVNRT). The aim of the study was to evaluate the effects of RF ablation on selected hemodynamic parameters of left ventricular (LV) systolic and diastolic function and exercise capacity in patients with AVNRT. MATERIAL AND METHODS: The study population consisted of 24 subjects (4 M, 20 F; mean age 42.7 +/- 8.1 years). Patients were submitted to ablation of the slow pathway. Those over 50 years of age, with concomitant cardiovascular disease and EF < 50% were excluded from the study. The following examinations were performed in all patients at baseline and at 6 months after the procedure: physical examination, standard ECG recording, 24 hr Holter monitoring, transthoracic echocardiography, treadmill exercise test using the modified Bruce protocol. RESULTS: After RF ablation left ventricular end-systolic dimension (LVESD) significantly decreased (31.1 +/- 3.9 vs. 28.3 +/- 3.7 mm; p < 0.001), whereas left ventricular ejection fraction (LVEF) increased (62.5 +/- 6.6 vs. 70.3 +/- 6.7%; p < 0.001) along with fractional shortening (FS) (34.5 +/- 4.8 vs. 39.3 +/- 5.3%; p < 0.001). Parameters of LV diastolic function significantly changed: the E/A ratio, diastolic pulmonary vein flow D and LV flow propagation velocity Vp significantly increased (p < 0.001, respectively) whereas systolic pulmonary venous flow S and pulmonary venous atrial reversal flow AR were significantly reduced (p < 0.001, respectively). Furthermore, E wave deceleration time (EDT) and isovolumetric relaxation time (IVRT) were significantly shortened (p < 0.001, respectively). All dimensions of the left, right atrium significantly decreased after the procedure (p < 0.001, respectively). In all groups parameters of exercise capacity were increased after the procedure. CONCLUSIONS: AVNRT has the negative effect on left ventricular systolic and diastolic function. In patients with AVNRT RF ablation improves left ventricular systolic and diastolic function. Elimination of AVNRT resulted in reduction of left, right atrial size. Exercise capacity improved significantly after RF ablation of AVNRT.