2 The procedure
2.1.1 Pulmonary valve stenosis is narrowing of the pulmonary valve in the heart. It is usually congenital. The outflow of blood from the right ventricle of the heart to the lungs is obstructed. Symptoms include shortness of breath, chest pains, fainting and, in some instances, sudden death.
2.1.2 Balloon dilatation is an alternative to open surgical valvotomy.
2.2.1 Balloon dilatation is a minimally invasive transvenous procedure to dilate the pulmonary valve orifice during cardiac catheterisation.
2.3.1 The evidence identified was limited to case series and one historical controlled study. All the studies reported a reduction in the residual pressure gradient across the pulmonary valve. In addition, the studies that reported data with more than 11 months follow-up showed that the reduction in pressure gradient persisted. In a case series of 533 children who received the procedure, an immediate residual gradient of less than 36 mmHg was reported in 74% (394/533) of patients. No clinical outcomes were reported. For more details, refer to the Sources of evidence section.
2.3.2 The Specialist Advisors considered this procedure to be established practice and had no concerns about its efficacy.
2.4.1 Most of the studies identified did not report safety findings in detail. The study that described safety findings in most detail reported the following immediate complications among 811 patients: arrhythmia, 1% (8/811); bleeding from catheter site, 0.9% (7/811); femoral vein thrombosis, 0.6% (5/811); hypoxia, 0.4% (3/811); death, 0.2% (2/811); tricuspid regurgitation, 0.2% (2/811); femoral vein tears, 0.2% (2/811); arterial thrombosis, 0.2% (2/811); cardiac perforation, 0.1% (1/811); and respiratory arrest, 0.1% (1/811). For more details, refer to the Sources of evidence section.
2.4.2 The Specialist Advisors commented that pulmonary regurgitation was common after the procedure, but that the long-term effects of this were unknown. They considered the risks to be greater in neonates than in older infants and children. The Advisors also recommended that the procedure should be carried out only in paediatric cardiology units with special expertise.