PERCUTANEOUS BALLOON DILATATION OF THE ATRIAL SEPTUM - IMMEDIATE AND MIDTERM RESULTS

Objectives-To assess the effectiveness of atrial septostomy by percuta neous balloon dilatation in patients with congenital heart defects or primary pulmonary hypertension. Patients and design-Twenty three patie nts (15 boys, eight girls; aged 10 days to 10 years; 17 with congenita l heart defects and six with primary pulmonary hypertension), all haem odynamically unstable under optimal medical treatment, underwent atria l septostomy by percutaneous balloon dilatation. Interventions-The bal loon catheter entered the left atrium through a patent foramen ovale ( n = 14) or via transseptal puncture in cases with an intact atrial sep tum (n = 9). The size of the balloons used ranged from 13 to 18 mm. Re sults-There were no complications. The interatrial communication (mm) increased (P < 0.05) after dilatation and remained unchanged (P = NS) during a 16.6 (13.8) month follow up (2 (1.7) v 8.8 (1.4) v 8.2 (1.1), respectively). Transatrial gradient (mm Hg) fell and arterial oxygena tion (%) improved both in patients with transposition (6.3 (0.8) v 0.8 (1)(P = 0.001) and 40.6 (4.2) v 76.5 (4.8) (P 0.0001), respectively) and in those with mitral atresia (13.4 (1.9) v 2 (1.4) (P = 0.001) and 77.1 (3.9) v 81.5 (4.2) (P = 0.008), respectively). There were two fa ilures, one early and one late, both in the group of patients with mit ral atresia or stenosis. A decrease in arterial oxygenation (94.8 (1.5 ) v 83 (2.4), P = 0.004) and an increase in left atrial pressure (6.8 (0.9) v 8.3 (12), P = 0.02) and cardiac index (2.3 (0.2) v 3.1 (0.2) 1 /min/m(2), P = 0.002) was observed in patients with primary pulmonary hypertension. Conclusions-Percutaneous balloon dilatation is an effect ive and safe procedure for creating an adequate interatrial communicat ion that can be used as an alternative to blade septostomy.