Noninvasive assessment of mitral inertness [correction of inertance]: clinical results with numerical model validation.
Inertial forces (Mdv/dt) are a significant component of transmitral flow, but cannot be measured with Doppler echo. We validated a method of estimating Mdv/dt. Ten patients had a dual sensor transmitral (TM) catheter placed during cardiac surgery. Doppler and 2D echo was performed while acquiring LA and LV pressures. Mdv/dt was determined from the Bernoulli equation using Doppler velocities and TM gradients. Results were compared with numerical modeling. TM gradients (range: 1.04-14.24 mmHg) consisted of 74.0 +/- 11.0% inertial forcers (range: 0.6-12.9 mmHg). Multivariate analysis predicted Mdv/dt = -4.171(S/D (RATIO)) + 0.063(LAvolume-max) + 5. Using this equation, a strong relationship was obtained for the clinical dataset (y=0.98x - 0.045, r=0.90) and the results of numerical modeling (y=0.96x - 0.16, r=0.84). TM gradients are mainly inertial and, as validated by modeling, can be estimated with echocardiography.
Firstenberg
M S
MS
The Cleveland Clinic Foundation, Cleveland, USA. firstem@ccf.org
Greenberg
N L
NL
Smedira
N G
NG
McCarthy
P M
PM
Garcia
M J
MJ
Thomas
J D
JD
D000368:Aged; D002315:Cardiopulmonary Bypass; D003971:Diastole; D015150:Echocardiography, Doppler / Q000379:methods / Q000706:statistics & numerical data*; D005260:Female; D006112:Gravitation; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D008955:Models, Cardiovascular; D015999:Multivariate Analysis; D015203:Reproducibility of Results; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000503:physiopathology; D017725:Ventricular Pressure