Left ventricular dysfunction and dilated cardiomyopathy in infants and children with wolff-Parkinson-white syndrome in the absence of tachyarrhythmias

Abstract

Left ventricular (LV) dysfunction and dilated cardiomyopathy (DCM) are rarely attributable to sustained or incessant tachyarrhythmias in infants and children with Wolff-Parkinson-White (WPW) syndrome. However, several recent reports suggested that significant LV dysfunction may develop in WPW syndrome in the absence of tachyarrhythmias. It is assumed that an asynchronous ventricular activation over the accessory pathway, especially right-sided, induces septal wall motion abnormalities, ventricular remodeling and ventricular dysfunction. The prognosis of DCM associated with asymptomatic WPW is excellent. Loss of ventricular pre-excitation results in mechanical resynchronization and reverse remodeling where LV function recovers completely. The reversible nature of LV dysfunction after loss of ventricular pre-excitation supports the causal relationship between LV dysfunction and ventricular pre-excitation. This review summarizes recent clinical and electrophysiological evidence for development of LV dysfunction or DCM in asymptomatic WPW syndrome, and discusses the underlying pathophysiological mechanism.

Keywords: Cardiomyopathy, dilated; Ventricular dysfunction, left; Wolff-Parkinson-White syndrome.

Fig. 1

Two-dimensional echocardiography in a 9-year-old girl with right anterior accessory pathway. A: bulging of basal septum with thinning (arrow) is seen in end systole prior to catheter ablation. B: paradoxical motion and bulging of basal septum (arrow) improves one month after catheter ablation.

Fig. 2

Radial strain assessment using 2-dimensional speckle tracking echocardiography. In the parasternal short axis view at the level of the mitral valve of a 9-year-old girl with a right anterior accessory pathway, radial strain assessment shows an inhomogeneous pattern with paradoxical negative value at the basal septal and basal anterior wall before radiofrequency catheter ablation (A). One month after ablation, inhomogeneity in the radial strain much improves and at the basal septal and basal anterior wall the radial strain reverts to a positive value (B).