Τίτλος:
PRESSURE-DIAMETER RELATION OF THE HUMAN AORTA - A NEW METHOD OF
DETERMINATION BY THE APPLICATION OF A SPECIAL ULTRASONIC DIMENSION
CATHETER
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
Background Pressure-diameter relation of the aorta provides important
information about the elastic properties of the vessel. However, owing
to methodological limitations, data regarding this relation are limited
in conscious humans. In the present study, we assessed a new method for
the direct estimation of the elastic properties of the aorta in
conscious humans by simultaneous acquisition of instantaneous aortic
pressure and diameter.
Methods and Results With this method, instantaneous diameter of the
thoracic aorta was acquired by a newly designed intravascular catheter
developed in our institution that incorporates an ultrasonic
displacement meter at its distal end. Instantaneous aortic pressure was
acquired simultaneously at the same aortic level with a catheter-tip
micromanometer. Aortic pressure-diameter loops were derived from
computer analysis of data. After in vitro and animal testing, elastic
properties of the aorta were investigated in coronary artery disease
(CAD) patients (n=15) and compared with those of control subjects
(n=10). Aortic distensibility was less in the CAD group than in the
control group (1.73+/-0.33 versus 3.95+/-1.09x10(-6)Xcm(2)Xdyne(-1),
P<.001). Compared with control subjects, the mean value of the slope of
the pressure-diameter loops was significantly greater in the CAD group
(38.89+/-8.75 versus 19.62+/-5.46 mm Hg . mm(-1), P<.001), whereas the
mean value of the intercept was lower in this latter group of patients
(-785.60+/-177.55 versus -313.43+/-126.41 mm Hg, P<.001). An excellent
correlation was found between the slope of pressure-diameter loop and
age in the group of control subjects (r=.827). Ninety-three percent of
the patients with CAD had values above the upper 95% confidence limits
of the control subjects (P<.001). In a third group of patients (n=16) in
whom assessment of pulse wave velocity was also included in the study of
the elastic properties of the aorta, pulse wave velocity had a strong
inverse correlation with aortic distensibility (r=-.95) and a strong
positive correlation with the slope of the pressure-diameter loop
(r=.97).
Conclusions This new method of determination of pressure-diameter of the
aorta enables an accurate and reliable evaluation of the elastic
properties of the aorta in conscious humans and may be useful for a
profound study of human aorta mechanics.
Συγγραφείς:
STEFANADIS, C
STRATOS, C
VLACHOPOULOS, C
MARAKAS, S and
BOUDOULAS, H
KALLIKAZAROS, I
TSIAMIS, E
TOUTOUZAS, K and
SIOROS, L
TOUTOUZAS, P
Εκδότης:
AMER HEART ASSOC
Λέξεις-κλειδιά:
ELASTICITY; PRESSURE; AORTA; WAVES; CATHETERS
DOI:
10.1161/01.CIR.92.8.2210
