[Acute changes in load: effects of myocardial velocities measured by doppler tissue imaging]

The value of measuring the velocities of myocardial motion in the analysis of regional contractility has been demonstrated. The effects of changes in load on myocardial velocities has not been extensively studied. The aim of this study was to increase the change in myocardial velocities during haemodialysis. The velocities of longitudinal myocardial motion of the posterior wall and mitral annulus were measured by Doppler tissue imaging in 33 chronic haemodialysis patients (16 men: ages 64 +/- 14 years). Using the apical 2 chamber view: systolic (S), diastolic (D) and late (A) velocities were measured before and immediately after haemodialysis. The weight loss and decrease in mean blood pressure was 2.6 +/- 1.2 Kg and 10 +/- 17% respectively. Before dialysis, the systolic and diastolic velocities were maximal at the mitral annulus and decreased from the base to the apical region of the posterior wall. After dialysis, the velocities of the basal, median and apical segments of the posterior wall increased in systole but decreased in early diastole. Conversely, diastolic velocities of the mitral annulus did not change after dialysis. The authors conclude that the systolic and diastolic velocities of myocardial motion are affected by acute changes in left ventricular load induced by haemodialysis whereas those of the mitral annulus are little affected.