Palliative balloon pulmonary valvuloplasty in tetralogy of fallot: echocardiographic predictors of successful outcome.

ABSTRACT

Although balloon pulmonary valvuloplasty (BPV) has been advocated as a means of palliating patients with tetralogy of Fallot (TOF), the results of this procedure were not uniformly good in this patient population. The purpose of this study was to review our institutionOs experience with BPV in patients with TOF, and to determine whether echocardiographic criteria exist that may be used to identify patients likely to derive prolonged benefit from this procedure. Between 1991 and 1999, nine patients with TOF, ages 0. 4Eth 26.1 weeks (mean, 7.4 +/- 7.6 weeks) underwent BPV due to cyanosis and other associated medical conditions (e.g., coronary artery anomalies, small size) that rendered immediate surgical intervention undesirable. Data from the catheterization and pre-BPV echocardiograms were analyzed. All patients had at least transient improvement in oxygen saturation. However, 4 patients (Group 1) required intervention (1 open-heart repair, 3 palliative shunts) within 5 weeks of BPV due to recurrent desaturation. In the remaining 5 patients (Group 2), open-heart repair was delayed 8Eth 36 weeks (mean, 23 +/- 13 weeks). Groups 1 and 2 did not differ regarding pulmonary valve annulus, main pulmonary artery or branch pulmonary artery diameter. However, the diastolic diameter of the right ventricular outflow tract (RVOT) was significantly smaller in Group 1 (18.3 +/- 3.5 mm/m2 versus 24.4 +/- 4.1 mm/m2 in Group 2; p < 0.05). Four out of five patients with a RVOT diameter < 23 mm/m2 were in Group 1, and all patients with RVOT diameter greater than 25 mm/m2 were in Group 2. We conclude that BPV can effectively palliate patients with TOF whose RVOT diastolic diameter is > 25 mm/m2. However, patients with a diastolic RVOT diameter < 23 mm/m2 are unlikely to have sustained improvement following BPV.