echocardiography: pre-ejection period (PEP) of aortic valve at end of expiration
echocardiography: pre-ejection period (pep) of aortic valve at end of expiration
echocardiography: pre-ejection period (PEP) of aortic valve at end of expiration
echocardiography: pre-ejection period (pep) of aortic valve at end of expiration