Artificial heart valve was later changed to use silicone-coated material. The first implantation of mechanical heart valve to human was performed by Dr. Hufnagel on 11 September 1952, using the valve that he developed. This event accelerated the development of other artificial heart valves. Artificial heart valve An artificial heart valve is a device implanted in the heart of a patient with valvular heart disease. When one of the four heart valves malfunctions, the medical choice may be to replace the natural valve with an artificial valve. This requires open-heart surgery. Valves are integral to the normal physiological functioning of the human heart.
Human rights in Argentina by the Argentine 601st Intelligence Battalion in mid-July 1978, which started counting victims in 1975, gave the figure of 22,000 persons. This estimate was first published by John Dinges in 2004. Estimates by human rights organizations were up to 30,000. The Montoneros admitted losing 5,000 guerrillas killed, and the ERP admitted the loss of another 5,000 of their own guerrillas killed. By comparison, Argentine security forces cite 775 deaths of their own. In contrast, there were 13,500 victims of left-wing terrorism in Argentina. There is no agreement on the actual number of "detenidos-desaparecidos". In an interview with Buenos Aires daily