Differences in regional diastolic function between restrictive and normal right ventricular physiology in adult patients late after tetralogy of Fallot repair

Background: Restrictive right ventricular physiology (RRVP) is a common finding in adult patients after tetralogy of Fallot (TOF) repair. Despite many attempts to relate this phenomenon to various factors, its clinical importance and the underlying myocardial pathologies are still enigmatic. Aim: We sought to evaluate the regional diastolic right ventricular (RV) function in patients after TOF repair with and without RRVP. Methods: A group of 112 consecutive patients with repaired TOF underwent transthoracic echocardiography with tissue Doppler imaging, cardiopulmonary exercise test, cardiac magnetic resonance, and laboratory test. Of them, 83 patients met the inclusion criteria. Regional deformations of the RV and interventricular septum (IVS) in patients with and without RRVP were compared. Results: Tetralogy of Fallot patients demonstrated an inhomogeneous pattern of strain rate (SR) values in the atrial contraction phase (A wave) of the RV free wall compared to healthy volunteers. Patients with RRVP had significantly lower values of A wave curves of IVS segments (velocities and SR) and higher values of RV free wall SR during early filling (E wave) and atrial contraction phases compared to patients without RRVP. In multiple factor analysis RRVP was correlated with lower values of end-diastolic IVS velocities (A wave) and higher values of RV SR A waves. Conclusions: Tissue Doppler imaging may show diastolic abnormalities in patients with RRVP. This group of patients demonstrated a deterioration in IVS diastolic function as measured by SR A waves. The diastolic function of RV free wall segments was better in patients with RRVP compared to patients without restriction of the RV measured by SR.