Relation between changes in coronary flow velocity and in wall motion for assessing contractile reserve during dobutamine stress echocardiography.

The purpose of this study was to determine the relationship between coronary flow velocity (CFV) measured by transthoracic Doppler echocardiography (TTDE) and wall motion during dobutamine stress echocardiography (DSE) in patients with resting wall motion abnormalities (WMAs). One hundred fifty patients with resting WMA in the left anterior descending coronary artery (LAD) territory underwent CFV recording in the distal LAD by TTDE during contrast-enhanced DSE. Regional wall motion, CFV, and CFV ratio, defined as a ratio of CFV at each stage of dobutamine stress to basal CFV, were obtained. Patients were divided into 4 groups (sustained improvement, biphasic response, worsening response, and no change). CFV was successfully recorded in 129 patients during DSE (86%). The mean value of basal CFV did not differ among the 4 groups. Although CFV ratio during DSE progressively increased in patients with sustained improvement, this increase was blunted with biphasic response and almost lost with worsening or no change response (P <.001, ANOVA). CFV ratio at peak stress was significantly higher in patients with sustained improvement (2.73 +/- 0.69) than that with the other 3 groups (P <.001). The value with biphasic response (1.68 +/- 0.56) was also higher than that with worsening (0.98 +/- 0.15, P <.005) and no change (1.28 +/- 0.38, P <.08). The simultaneous assessment of CFV and function in the LAD territory is feasible, and flow and function are closely correlated. TTDE provides flow information that may complement conventional echocardiographic assessment of myocardial viability.