Development of catheter techniques to treat native and acquired stenoses in congenital heart disease

Abstract

Aim: To describe innovative uses of catheter based treatment in a variety of native and post surgical stenoses in children and young adults with congenital heart disease. Background: Cardiac catheterization in man was first described 1929 and since then there has been a drive to develop endovascular techniques to investigate and treat both congenital and acquired heart disease. Many of the advances are being made in congenital heart disease. Methods: A number of congenital cardiac stenotic lesions were studied including baffle obstruction after atrial switch for transposition of the great arteries, aortic stenosis in infants, coarctation of the aorta, peripheral pulmonary artery stenosis and superior vena caval obstruction. The use of angioplasty balloons, cutting balloons, stents and alternative catheter approaches were investigated for these lesions. Results: Following atrial redirection surgery for transposition of the great arteries balloon angioplasty improved baffle haemodynamics. The technique of anterograde balloon dilation of the aortic valve was developed and had superior outcomes in terms of aortic insufficiency compared to a retrograde approach in neonates with severe aortic valve stenosis. In an animal model of peripheral pulmonary arterial stenosis, the application of cutting balloon angioplasty produced effective relief in a controlled fashion. Balloon mounted stents were used in patients with native and post surgical coarctation of the aorta with significant relief of stenosis and relief of hypertension. Finally, a group of patients with superior vena obstruction syndrome after surgical repair of partial anomalous pulmonary venous drainage had successful treatment using balloon mounted stents. Conclusions: Catheter based treatment of congenital and post surgical vascular stenoses of the heart and great arteries using angioplasty balloons, cutting balloons and balloon mounted stents is safe and appears to be effective in the short and medium term. It may represent a useful alternative to surgery and will reduce the number of surgical procedures required over a lifetime. Future directions will include bio-absorbable stents and hybrid techniques involving surgery.