Diastolic response during dobutamine stress echocardiography evaluated by a tissue velocity imaging technique is a...

Tissue velocity imaging (TVI) is a new method that measures regional myocardial velocities on the basis of color Doppler myocardial imaging principles.

To diagnose coronary artery disease (CAD) objectively by evaluating left ventricular diastolic responses during dobutamine stress echocardiography (DSE) with TVI, we performed DSE in 22 healthy participants and 28 patients with angina pectoris without wall-motion abnormality at rest. Before and during DSE, we measured the differences of time intervals from the R wave on electrocardiogram to the peak of early diastolic myocardial velocity in the same cardiac cycle between basal segments and midsegments in the septal (dT-S) and inferior (dT-I) walls by TVI.

During DSE, dT-S in patients with left anterior descending CAD and dT-I in patients with right CAD were prolonged compared with that in healthy participants (both P <.01). The localization of the segments with a dT-S or dT-I during low-dose (10 microg/kg/min) dobutamine infusion of >32 milliseconds allowed the correct identification of the stenosed vessel in 87% of 23 patients for whom DSE was performed with the TVI technique before coronary angiography.

The analysis of regional left ventricular diastolic responses to dobutamine stress using TVI was useful for the objective diagnosis of CAD.