To examine the blood flow cynamics in descending thoracic aorta (DAo) in normal subjects (N) and patients (Pts) with cardiovascular, diseases, we analyzed the flow velocity patterns (FVP) in DAo and its cimension at the level of mitral valve by 2-D biplane transesophageal chocardiography (TEE) in 25 control subjects, 2 Pts with aortic stenosis (AS), 7 aortic regu rgitaion (AR), and 9 aortic true aneurysm (AN). We obtained the laminar flow at three sampling vplumes (SV) in DAo on a longitudial scanimage of DAo