1- Percutaneous treatment of valve stenosis can now be effective in a high percentage of cases either in newborns or in adult patients. Indeed, pulmonary or aortic valve dilation can be performed using one or two balloons with very good early and long-term results. Systemic or pulmonary vessel stenosis (either native or post-surgical) can be effectively treated by balloon angioplasty or stent implantation. High-pressure or cutting balloons are highly useful for native lesions, while the relief of post-surgical stenoses can be achieved by stent implantation. To date, the only significant limitation to this latter approach is the size of the patient in terms of potentiality of growth, although the use of bio-absorbable stents could overcome this drawback, allowing the treatment of even newborns or small infants. Native aortic coarctation can be effectively approached by balloon dilatation in newborns and infants, while stent implantation is suggested in patients older than 8 years of age. However, post-surgical re-coarctation can be successfully treated by balloon angioplasty (preferably in low-weight patients) or stent implantation.
2- Percutaneous closure of atrial septal defect and patent foramen ovale is possible in most patients using devices with different mechanism and physiology. This approach makes it possible to tailor the device to the defect anatomy and size. Early and longterm results of this technique are very satisfactory, with closure rate near to 100% and very low complications rate. Device closure of muscular ventricular septal defects is possible and safe also in low-weight infants, while the percutaneous approach to membranous ventricular septal defect should be indicated in patients older than 6 years due to high risk of heart block in younger patients. Patent ductus arteriosus can be safely approached by percutaneous techniques at any age, although this treatment is more challenging in patients weighting less than 5 kg. The most used device are detachable coils or Amplatzer Duct Occluder devices, with very high success rate and low complication rate.
3- The first percutaneous pulmonary valve replacement was performed almost 10 years ago by Bohnoeffer et al. Nowadays, this approach is widely used in patients older than 5 years and/or weighting more than 20 kg with pulmonary conduit stenosis and/or insufficiency. In these patients the Melody® valve can be effectively implanted with a high rate of success and anticipated good effectiveness over a mid-term follow-up.
Total Pages: 153-187 (35)
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