Application of Ambrisentan in preventing cardiac function impairment due to lack of oxygen

The invention relates to a novel application of Ambrisentan in preventing cardiac function impairment due to lack of oxygen. The invention particularly relates to an application of Ambrisentan and its pharmaceutically acceptable salt in preparing medicines for preventing the cardiac function impairment due to the lack of oxygen. The invention also relates to a medicine box product, comprising a medicine composition and an instruction manual, wherein, the medicine composition comprises prophylactically effective amount of Ambrisentan or its pharmaceutically acceptable salt and an optional pharmaceutically acceptable carrier or excipient, and the instruction manual documents information of using the medicine composition to prevent the cardiac function impairment due to the lack of oxygen. According to the invention, Ambrisentan can effectively prevent the cardiac function impairment due to the lack of oxygen.