Assessment by Tissue Doppler Imaging of Effect of Volume Reduction on Diastolic Function in Hemodialysis Patients

Doppler tissue imaging (DTI) is a new echocardiographic application which allows non-invasive assessment of left ventricular systolic and diastolic performance. Our aim was to determine the DTI parameters of patients before and after hemodialysis and to evaluate if this method was preload dependent or not. Our study included 40 chronic hemodialysis patients (17 female and 23 male) aged between 20 and 75 (mean 48 ± 14) years. Doppler echocardiography and pulsed DTI echocardiography were performed by the same physician to patients before and 1 hour later after the same hemodialysis session. We measured standard Doppler parameters (early diastolic (E) velocity, late diastolic (A) velocity, E/A ratio, deceleration time and isovolumic relaxation time) and tissue Doppler parameters (mitral annular early diastolic (e) velocity, mitral annular late diastolic (a) velocity, e/a ratio).
RESULTS
E and e waves decreased after hemodialysis in all patients (p<0.001 and p=0.002). In the patients who were ?45 years old, E wave decreased significantly (p=0.003) but e wave did not change significantly (p=0.16). In the patients who were >45 years old both E and e waves decreased significantly (p<0.001 and p=0.007). Decceleration time and isovolumic relaxation time did not change. E/A ratio decreased significantly in patients over 45 years old (p=0.004) but not in those under 45 years old (p=0.08). In both groups e/a ratio did not changed significantly. There were no statistically significant differences between groups in regard to when diabetes mellitus, hypertension and gender (p>0.05). In conclusion, both mitral inflow velocities and mitral annular velocities are volume-dependent in subjects over 45 years. However, in subjects under 45 years old, mitral annular velocity is independent of volume whereas mitral flow velocity is dependent. Diastolic functions may be evaluated with DTI in subjects under 45 years old.