Are Left Ventricular Diastolic Filling Velocities as Assessed by Doppler Tissue Imaging Independent from Preload ?

Pulsed Doppler indexes of diastolic filling have been used as measures of left ventricular diastolic function. However, various hemodynamic factors and Ioading conditions influence the pattem of LV filling. Doppler tissue imaging (DTI) is a new technique for assessment of regional systolic and diastolic left ventricular function. The aim of the present study has been to evaluate whether the diastolic mitral annular velocities by Doppler tissue imaging are affected by changes in preload conditions. Pulsed Doppler transmitral inflow velocities (E, A), diastolic mitral annular velocities at the lateral (LatE, LatA) and septal (SepE, SepA,) side of the mitral annulus by pulsed DTI, and the ratio of peak early to peak atrial filling velocities (E/A, LatE/A, SepE/A) were assessed in 38 subjects (age 56 ± 9 years) with coronary artery disease at baseline and after nitroglycerine administration. All measures were performed at end expiration and averaged over three cardiac cycles. Heart rate increased from 68 ± I O to 77 ± 12 beats/ min (p<0.001). The E, LatE, and Sep E velocities (cm/see) decreased from 68.7 ± 25.6 to 54.2 ± 18.7 (p<0.0001), from 9.2 ± 3.2 to 8.1 ± 2.6 (p<0.001), and from 7.4 ± 2.8 to 6.6 ± 2.6 (p=0.001), respectively. The A, LatA, and SepA velocities were not significantly changed (68.6 ± 21.2 vs. 71.3 ± 21.4; p=0.518, 9.4 ± 2.4 vs. 9.5 ± 2.5; p=0.721 , 8.8 ± 2.0 vs. 8.7 ± 2.0; P=0.521, respectively). The E/A, LatE/ A, and SepE/A decreased from 0.98 ± 0.33 to 0.87 ± 0.36 (p=0.0001), from 1.07 ± 0.59 to 0.92 ± 0.44 (p=0.0002), and from 0.87 ± 4.2 to 0.78 ± 3.2 (p=0.0049), respectively.
CONCLUSIONS
Alterations in preload significantly altered the pattem of diastolic filling as assessed by DTI of mitral ann u lar velocities in a similar manner to the pulsed Doppler transmitral flow velocity profile.