Freudenthal is known for his
Nit Occlud device for treatment of an infant heart problem. The prototypes were first tested on sheep, and since then have been used successfully by Freudenthal on hundreds of children, and have been exported around the world. The device treats a
congenital disorder in the heart known as a
patent ductus arteriosus (PDA). This occurs when the
ductus arteriosus blood vessel, which bypasses the lungs before a baby is born, fails to close up soon after birth. The affected infant suffers from labored breathing, failure to gain weight and other problems. The condition is much more common in Bolivia, where the country around La Paz is at an elevation of , than in other places. The device is made from a single wire of
nitinol, a flexible alloy of
nickel and
titanium. Nitinol was originally developed by the US military. The tiny
Nit Occlud devices are small and intricate, and difficult to mass-produce. Instead they are woven by
Aymara women in a "clean room". It takes about two hours to make each device. The device can be placed without an invasive operation, using
cardiac catheterization. Nitinol is able to memorize its shape. The device is folded up and inserted into a catheter which is inserted into the groin and then run through blood vessels to the position in the heart where it is to be placed. The device is released and returns to its original shape, blocking the hole that caused the heart problem. By using a minimally invasive approach the technique addresses the concerns of some indigenous people of Bolivia that to manipulate the heart is to desecrate the soul. It takes about 30 minutes to place the device. Technically, the Nit-Occlud ASD-R, is a double-umbrella, self-expanding, self-centering and premounted device knitted from a single nitinol wire without any soldering or protruding clamps or screws. The Nit-Occlud is similar to other self-expandable devices, which have provided excellent long-term clinical outcomes. The device has a unique shape that offers various advantages and a special snare-like release mechanism. It ranges in size from in
stent diameter. The first human implantation was done at the La Paz Kardiocentrum by Alexandra Heath and coworkers. 53 implantations were made by this group from May 2007 to February 2011. Four attempts failed. Of the 53 implantations, complete closure occurred immediately in 71% of patients, and 100% after six months. Findings are generally very positive, although the erosion rate is not yet known. In August 2014 it was announced that Freudenthal had won the "Innovators of America" award in the Science and Technology category for his occlusion device to cure congenital heart disease in children. The award is given by Innovative America, is sponsored by the
CAF – Development Bank of Latin America and the Caribbean and the Spanish CAF Ezentis group, and was to be presented in
Medellín, Colombia on 21 August 2014. As of 2014 the device had cured at least 50,000 children worldwide, and about 500 in Bolivia. ==References==