抄録
Objective. We investigated whether pulsed tissue Doppler imaging could be useful to detect sensitively a decrease in left ventricular (LV) contractile force and development of systolic asynchrony during an increase in afterload in healthy individuals.
Methods. We recorded LV wall motion velocities before and after angiotensin II infusion by pulsed tissue Doppler imaging in 16 healthy individuals and evaluated the differences in the responses in systolic LV function along the short- and long-axes between the basal and apical regions during an acute increase in afterload.
Results. After angiotensin II infusion, the systolic blood pressure and LV end-systolic dimension were increased significantly, and the LV ejection fraction was significantly decreased. The peak first and second systolic velocities and the times from the beginning of the Q wave of the electrocardiogram to the peak first systolic velocity of the LV walls along both the short- and long-axes were markedly decreased and prolonged, respectively, in the apical region compared to the basal region.
Conclusions. LV systolic asynchrony is induced, even in normal hearts, during an increase in afterload. Pulsed tissue Doppler imaging provides incremental diagnostic information on regional LV systolic function.
