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).
Cardiovascular Biophysics Laboratory, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO 63110, USA.
Lisa
L
Bauman
Charles S
CS
Chung
Mustafa
M
Karamanoglu
Sándor J
SJ
Kovács
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*