Abstract #3559
Measurement of
Changes in Left Ventricular Volume and Strain During Isovolumic Relaxation
June Cheng-Baron1, Kelvin Chow1,
Ben T. Esch2, Jessica M. Scott2, Mark J. Haykowsky2,
John V. Tyberg3, Richard B. Thompson1
1Biomedical Engineering, University of
Alberta, Edmonton, AB, Canada; 2Physical Therapy, University of
Alberta, Edmonton, AB, Canada; 3Cardiac Sciences, University of
Calgary, Calgary, AB, Canada
Left
ventricular (LV)
volume estimated using ventricular dimensions or surface markers have shown
increasing volume during isovolumic relaxation, despite closed mitral and
aortic valves. The goal of this study is to explain and interpret this volume
increase in the context of ventricular relaxation. We measure a 4.6 mL mean
increase in LV
volume, which is correlated with changes in principle myocardial strains and
compensated for by the descent of the mitral leaflets towards the apex. The
motion of the leaflets and conformational changes in the LV
during isovolumic relaxation likely reflect LV pressure decline and the development of
ventricular suction.
