THE EFFECTS OF SUPRAVALVULAR AORTIC-STENOSIS ON REALISTIC 3-DIMENSIONAL LEFT-VENTRICULAR BLOOD EJECTION

The effect of supravalvular aortic stenosis on cardiac left ventricular ejection was determined from a realistic left ventricle (LV) model built from the profile of a diastolic dog LV. The ejection fraction was considered to be 75% of the diastolic volume. The maximum blood ejection velocities and ventricular pressure occurred at the start of the diastolic flow since the ventricular walls moved the fastest at this point. Going from a healthy non-stenotic LV to one with 64% stenosis increased the maximum ejection velocity from 117 cm/sec to 269 cm/sec, and the maximum relative pressure increased from 10,420 dynes/cm(2) to 33,550 dynes/cm(2) (7.82 to 25.16 mm Hg). The supravalvular stenotic aorta showed major flow disturbances as the degree of stenosis increased. The computational technique using a realistic model gives predictions in general agreement with observed experimental results, and allows a complex determination of the three-dimensional flow patterns.