Relation between age at surgery and regression of right ventricular hypertrophy in tetralogy of Fallot.

Pre- and postoperative echocardiographic right ventricular wall thickness (RVW), transverse dimension (RVD), and their ratio (W/D) were measured from subcostal views in 29 patients with Tetralogy of Fallot (TOF) in order to assess whether primary reparative surgery without prior palliative shunts in early infancy results in significantly faster regression of RV hypertrophy than repair later in life. Fourteen patients who were repaired before 6 months of age were compared with 15 patients who were repaired after 6 months of age. In the group of patients who were repaired before 6 months of age both RVW and W/D ratio decreased significantly whereas RVD did not change from pre- to postoperative status. The group of patients who were repaired after 6 months of age showed no significant changes in RVW, RVD, or W/D ratio. These findings suggest that early primary reparative surgery of TOF may have a positive effect on faster regression of RVH during the first postoperative year which may reduce the detrimental effect of longstanding hypertrophy on myocardial function and the potential for arrhythmia.