Objective: Aim of the study was to compare long-term effects of right ventricular (RV) overloads on global function and regional deformation indices in patients with tetralogy of Fallot (TOF, pressure and/or volume overload model) and in patients with atrial septal defect (ASD, volume overload model). On standard echo examination both groups were not different in terms of RV end-diastolic diameter.
Methods: 50 adults (24F/26M) aged 18-52 yrs after total repair of TOF and 40 patients (30F/10M) with ASD with significant left-to-right shunt were examined. Patients were characterized by tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC) and myocardial performance index (MPI). Regional longitudinal systolic and diastolic Strain Rate (SR) and maximal strain (S) were analyzed off-line using GE Echopac 2D Strain. All values were averaged from three consecutive heart cycles.
Results: We found no difference in FAC and MPI between ASD and TOF patients (FAC 0,26 vs 0,29; MPI 0,39 vs 0,41). TAPSE was significantly increased in patients with ASD (32,8 mm vs 20,7 mm; p<0,05). Maximal strain values were significantly lower in subjects with TOF for all analyzed RV segments (-20,92% vs -27,37% for basal; -20,14% vs -31,81% for mid; -18,42% vs -33,05% for apical segments, respectively).
Conclusions: Comparing to ASD, TOF patients demonstrate impaired regional RV function. Among the RV global function indices only TAPSE distinguishes between patients with RV volume and pressure/volume overload.