Rudimentary ventricle in univentricular physiology.

We thank Yurekli et al. [1] for their comment. In our study, we chose to evaluate ventricular function in patients with functionally single-ventricle hearts by echocardiographic analysis of the main systemic pumping chamber without regard to the contractile effects of the diminutive ventricle. We showed that natriuretic peptide levels decreased during the treatment protocol for UVH [2]. This reflects the reduction of volume overload of the single ventricle. However, even after a TCPC operation, NT-proBNP levels remained higher than in the controls. This may be due to various reasons. As Yurekli et al. pointed out, one of them may well be the rudimentary ventricle disturbing the systemic ventricular function [1]. This is however difficult, if not impossible, to prove reliably in a clinical study.