The peak atrioventricular pressure gradient to transmitral flow relation: kinematic model prediction with in vivo validation.
Physiologists and cardiologists estimate peak transvalvular pressure gradients (DeltaP) by Doppler echocardiographic imaging of peak flow velocities using the simplified Bernoulli relationship: DeltaP (mm Hg) = 4V(2) (m/s). Because left ventricular filling is initiated by mechanical suction, V can be predicted by the motion of a simple harmonic oscillator by the parametrized diastolic filling formalism that characterizes E-wave contours by 3 unique simple harmonic oscillator parameters: initial displacement (x(o) cm); spring constant (k g/s(2)); and damping constant (c g/s). Parametrized diastolic filling predicts peak atrioventricular pressure gradient as kx(o), the peak simple harmonic oscillator force. For validation, simultaneous (micromanometric) left ventricular pressure and E-wave data from 19 patients were analyzed. Model-predicted peak gradient (kx(o)) was compared with actual gradient (DeltaP(cath)) and with 4V(2). Multiple linear regression results for all patients yielded highly significant relation between kx(o) and DeltaP(cath) (kx(o) = m(1)DeltaP(cath) + b(1), where m(1) = 40.7 +/- 8.0 dyne/mm Hg, b(1) = 1540 +/- 116 dyne, r(2) = 0.97, P <.001). Regression analysis showed no significant correlation between 4V(2) and DeltaP(cath) (4V(2) = m(2)DeltaP(cath) + b(2), where m(2) = 0.01 +/- 0.03, m(2)/s(2)/mm Hg and b(2) = 2.07 +/- 0.44 m(2)/s(2), P = nonsignificant). We conclude that E-wave analysis by parametrized diastolic filling predicts peak atrioventricular gradients reliably and more accurately than 4V(2).
Bauman
Lisa
L
Cardiovascular Biophysics Laboratory, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO 63110, USA.
Chung
Charles S
CS
Karamanoglu
Mustafa
M
Kovács
Sándor J
SJ
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity; D006328:Cardiac Catheterization; D003971:Diastole / Q000502:physiology*; D015150:Echocardiography, Doppler; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000000981:diagnostic imaging* / Q000502:physiology*; D008955:Models, Cardiovascular; D017725:Ventricular Pressure / Q000502:physiology*