Non-surgical treatment of congenital heart disease.

Dilation of blood vessels transluminally was demonstrated by Dr Andreas Gruntzig in 1978. In 1982, Kan demonstrated that congenitally stenosed valve can be dilated with the use of cylindrical balloon and opened up new vistas in the non-surgical treatment of congenital heart lesions. Rapid progress has been now made in (1) Understanding of mechanism of success or failure of balloon dilation (2) Development of newer hardwares like low profile balloon, high pressure balloons, extra support wires which have contributed to increase in success rate of the procedures (3) Understanding the unnatural history of various congenital heart lesions from the vast data bank of Registries of balloon dilation. As a consequence balloon dilation has become the first procedure of choice in the treatment of valvar pulmonary stenosis and post surgical recurrent coarctation. Although an essentially palliative procedure for the treatment of valvar aortic stenosis and native coarctation beyond the neonatal period, non-randomised studies have shown results similar to that of surgical correction. Balloon dilation of pulmonary artery, pulmonary vein, venous baffles stenosis have shown poor overall results. Balloon dilation for sub-pulmonary stenosis like tetralogy of Fallot is controversial. The development of stents to keep dilated vessel open has also found a place in treatment of congenital heart lesions. Thus pulmonary artery stenosis, recurrent coarctation in adults, venous baffle obstruction, conduit stenosis which respond poorly to balloon dilation alone have shown promising early and mid term results with stents. The use of stents to keep the ductus open, recurrent coarctation in children, in right ventricular outflow tract obstruction is controversial. Development of devices to achieve closure of cardiac defects is relatively new. Patent arterial duct was the first defect to be closed with the help of devices and has shown good results on long term follow up. Recently stainless steel coils have been used to close dose small ducti (up to 3 mm) with very promising medium term results. Its use has also been extended to larger ducti (up to 7 mm). Devices used for closing atrial septal defects, ventricular septal defects are undergoing rapid development. In atrial septal defects its use is restricted to small defects in the fossa ovalis area and in ventricular defects, to only those which are in the muscular septum. Most of the devices in use today for atrial septal closure are relatively new and await long term results. The results achieved by non surgical treatment for many congenital heart lesions are essentially palliative and may require repeat interventions at some point in the unnatural history which increases the cost of treatment substantially. The reuse of balloons, guide wires in developing countries helps reduce the overall cost of the procedure.