Visakhapatnam: Doctors at Visakhapatnam's King George Hospital (KGH) on Monday refused to conduct clinical trials of a ventilator that has been billed as a vastly cheaper alternative to imported equipment.   The ventilator was assembled at the Andhra Pradesh Medtech Zone (AMTZ), a 270 acre facility promoted by the government of Andhra Pradesh to push medical device manufacturing in India and reduce import dependence. AMTZ chief executive officer Jitendra Sharma has been claiming that t