Clinical Research
Clinical Research Papers
The Assessment of Systemic
Vascular Compliance During Cardiac Output Measurement to Evaluate
Cardiovascular Loading Status
Hu W-C, Hsu T-L, Brinton TJ, Tai L-C,
Chio S-S, Wang S-P, Chang M-S, Liu C-P, Veterans General
Hospital- Taipei, Taiwan, R.O.C.
Systemic
vascular compliance (SVC), dV/dP, is an important index of
cardiovascular loading status. SVC was determined using cardiac
output (CO) derived by thermo-dilution and non-invasive pulse
pressure (PP) and heart rate measurement obtained by a new
oscillometric technology, SVC=CO/(PP*HR). SVC measurement
obtained by this method were compared to the effective arterial
elastance (Ea) obtained by micromanometer tipped catheter in 30
myocardial infarction (MI) and 20 control patients. By
definition, SVC corresponds inversely to Ea which was determined
by the ratio of left ventricle developed pressure to stroke
volume. A good correlation (r=0.85) was observed between SVC and
IlEa (top figure). In order to evaluate the relationship between
blood pressure load and cardiovascular loading status, SVC was
compared to mean arterial pressure (MAP) in both MI and control
patients. The relation between SVC and MAP is best fitted with a
second order polynomial (r=0.77) and the data of both groups
follows the same fitting function (lower figure). The results
suggest that SVC can be accurately assessed during cardiac output
measurement utilizing a new non- invasive blood pressure and
heart rate technology and results are not significantly affected
by disease state.
*Presented at the American College of
Cardiology 45th Annual Scientific Sessions, March 1996. (See
Journal of the American College of Cardiology 1996 Vol 2~ No.2,
Supplement A, pg. 119A).
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