“…Additionally, Daliento et al [26] have proven the presence of fibrosis of the right and left ventricular myocardium observed in histopathological study performed as early as in neonatal age. The maximum heart rate in our group of patients was lower than in controls, which may indicate, according to some other authors, the impairment of chronotropic reaction in Ebstein's anomaly [22,24,30,31]. The limited chronotropic response that may result from sinus node dysfunction, right bundle branch conduction disorders or sympathetic tone changes [32,33], was also noted in patients presenting with other congenital heart anomalies [30,32,34 -36].…”