| Abstract: | Seventeen consecutive newborn and premature babies with critical pulmonary stenosis underwent a technically successful balloon valvuloplasty at our institution from March 1991 to February 1998. The only major complication was a thrombosis of the femoral vein in one patient, causing no clinical problems. Four patients (24%) showed a reactive infundibular obstruction after balloon valvuloplasty. The outflow tract obstruction became evident immediately after successful dilatation of the pulmonary valve with persistently high pressures in the right ventricle. Pathognomonic was a typical notch in the ascending part of the right ventricular pressure curve. We were unable to predict this reaction based on echocardiography or angiography. To relieve the muscular subvalvar obstruction, we treated the first two patients with i.v. Propranolol (0.05 mg/kg over 2 min). The last 2 patients received Esmolol (0.5 mg/kg over 2 min followed by a continuous infusion with 100 micrograms/kg/min), a very short acting beta-blocker. In the medium-term follow-up, all 17 patients had a very good result with only mild pulmonary valve regurgitation. All 4 patients with a reactive infundibular obstruction required no repeat intervention. In the medium-term follow-up there were no differences between these 4 patients and the whole group. |
