Effect of Ventricular Preexcitation on Left Ventricular Function in Pediatric Patients with Wolff–Parkinson–White Syndrome

Abstract

Background: Wolff Parkinson White syndrome with ventricular preexcitation may cause cardiac dysfunction and dilated cardiomyopathy even in the absence of recurrent and incessant tachycardia. Purpose: This study aimed to determine the effect of ventricular preexcitation on cardiac function in pediatric patients with manifest accessory pathway. Methods: We analyzed the clinical data of 20 patients who underwent electrophysiological examination and radiofrequency catheter ablation (RFA) for paroxysmal supraventricular tachycardia associated with accessory pathway [male : female, 8 : 12; age, 12 (0.8 16) years]. We divided the patients into two groups: patients with ventricular preexcitation (manifest group, n 12) and those without ventricular preexcitation (concealed group, n 8). Results: LVEF before RFA was within the normal range in all patients but was significantly lower in the manifest group than in the concealed group [manifest group vs. concealed group, 66.0 (47.7 74.5 ) vs. 78.1 (70.1 83.0 ); p 0.001]. LVEF increased after RFA in the manifest group 66.0 (42.7 74.5 ) vs. 74.4 (52.7 80.7 ); p 0.003]. No change was observed in the LVEF after RFA in the concealed group. Cardiac dysfunction was detected in two patients, with the LVEF of 53.1 and 42.7 , respectively. Both patients were in the manifest group, and the accessory pathway was located at the right posterolateral and right anterolateral, respectively. The LVEF after RFA in these patients improved to 75.7 and 52.7 , respectively. Conclusions: The LVEF was lower in patients with manifest accessory pathway than in patients with concealed accessory pathway, and the LVEF was shown to increase by the disappearance of preexcitation of the manifest accessory pathway.