the use of ultrasound (= sound waves used to produce images of the inside of someone's body) to examine the structure of the heart and how well it is working

Researchers used echocardiography to test the effects of the drug on climbers' hearts and lungs on Mount Everest. 研究人员用超声波心动描记术来测试这种药物对喜马拉雅山上的登山者心肺的影响。