Percutaneous implantation of the pulmonary and aortic valves: indications and limitations.

Percutaneous transcatheter intervention for valvular heart disease is the new horizon in transcatheter therapeutics. Balloon dilatation has been used successfully for treatment of congenital and acquired stenotic lesions of semilunar and atrio-ventricular valves. Although attempts have been made to repair and replace cardiac valves without cardiopulmonary bypass and through percutaneous techniques, this has only recently become a reality. The semilunar valves have preceded atrioventricular valves in successful application in animals and humans. Morphological features play an important role in determining the design of the valve and technique and site of implantation. The major deviations in research and development in artificial or tissue valves have included attempts at delivery of these valves to the site of implantation without open heart surgery. Successful implantation needs long-term follow-up for the durability of the valve and freedom from re-intervention.