[Comparison of right ventricular function between prevention and enlargement of pulmonary valve annulus after repair of tetralogy of Fallot; mid-term results].

: Total of 41 patients with tetralogy of Fallot (TOF) who underwent intracardiac repair from 1993 to 1998 were divided into 2 groups: preservation (n = 14) or enlargement (n = 27) of the pulmonary valve annulus. The procedure was decided on the Z value of the annular size: above or under -2 SD of the standard value. Although postoperative right ventricular (RV) diastolic volume (RVEDV) and cardiothoracic ratio (CTR) were larger than the preservation group and pulmonary regurgitation (PR) existed in the enlargement group, RV pressure was decreased and central venous pressure (CVP) was low and RV contraction was preserved. The exercise capacity was also good and no significant arrhythmia was recognized. Our mid-term results showed that appropriate enlargement of the pulmonary valve annulus preserved good RV function in patients with TOF.