Clinical Research
Clinical Research Papers
A New Non-Invasive Method
for Detection and Assessment of Aortic Regurgitation During
Routine Blood Pressure Recordings
Brinton TJ, Hsu T-L, Kwan O-L, Liu C-P,
Chang M-S, Chio S-S, DeMaria AN; Veterans General Hospital -
Taipei, Taiwan, R.O.C., and UCSD, La Jolla, CA.
Recently,
we developed an oscillometric cuff technique (CUFF) to
non-invasively derive arterial pressures and waveforms. Using
this method we observed a unique pattern of pressure oscillations
(PO) in a pt with severe aortic regurgitation (AR). To further
define the potential mechanism of this phenomenon, and its value
in the detection and assessment of AR, we performed clinical and
modeling studies. CUFF was performed in 10 normal (N) and 15 pts
in whom AR was documented and semi-quantitated by echo. In 10 N,
and all 5 mild AR pts, a bell shaped distribution of PO was
observed from supra-systolic to sub-diastolic cuff pressure.
However, all 10 pts with grade III (severe) AR exhibited a phasic
alteration of PO conforming to a resonance pattern. To test the
hypothesis that this phenomenon represented a
ventricular-vascular fluid mechanics interaction produced by AR,
we utilized a simple amplitude modulation model (Wl=incident,
W2=reflection) and found that the pattern could be reproduced at
specific amplitudes and frequencies. Thus, CUFF recordings of
arterial pressure exhibit a marked resonance pattern in pts with
severe AR, likely due to ventricular-vascular fluid mechanics
interaction. This phenomenon should be useful in detecting and
assessing AR during routine blood pressure recordings.
*Presented at the American College of
Cardiology 45th Scientific Sessions, 1996 (see Journal of the
American College of Cardiology 1996 Vol 27, No.2, Supplement A,
pg. 87A).
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