[Comparison of continuous wave Doppler and heart catheterization in the determination of the mean transvalvular gradient in XXXX . A simultaneous beat to beat analysis].

@entity1 @entity955 @entity4794 @entity340 @entity551
Continuous wave Doppler echocardiography (CWD) is widely used in the assessment of pressure gradients in @entity1 with @entity340 , utilizing the simplified Bernoulli equation. However determination of non-simultaneous @entity551 ( @entity551 ) in @entity4794 ( @entity4794 ) from CWD recordings has often been described as being unsatisfactory. Therefore, the purpose of this study was to compare the estimates of trans-mitral @entity551 derived from CWD with gradients measured simultaneously at cardiac catheterization (beat to beat analysis). We studied 3 @entity1 (pts) with @entity4794 (1 @entity1 and 2 @entity1 , aged 55, 55 and 62 years respectively); one @entity1 (pt) was in sinus rhythm and 2 were in @entity955 . In each pt the trans-mitral flow velocity curve was obtained simultaneously with trans-mitral gradient measured directly at cardiac catheterization (cath). In this way it was possible to obtain a beat to beat correlation between Doppler and cath in 181 beats taken from the 3 pts. These beats were selected from a total number of 321 beats because of their excellent quality for analysis (74 beats were obtained from the first pt, 38 from the second pt and 69 from the third pt). Mean diastolic velocity, defined as the mean of maximal velocities throughout diastole, was obtained for each beat by planimetring the envelope of the spectral velocity profile. @entity551 was calculated from mean velocity by applying the simplified Bernoulli equation (delta P = 4V2).(ABSTRACT TRUNCATED AT 250 WORDS)
