The diagnostic value of Doppler echocardiographic indexes of diastolic filling for detecting demand ischemia in anesthetized patients

In awake patients, Doppler indexes of transmitral flow velocities have been shown to be more sensitive for detection of myocardial ischemia than echocardiographic evaluation of systolic wall-motion. The diagnostic value of these indexes in anesthetized patients is unknown. It might differ from that in awake patients because anesthetics and sympathomimetic drugs, which are commonly used in surgical patients with coronary artery disease (CAD), independently affect transmitral flow velocities. Methods: Several previously published transmitral Doppler echocardiographic indicators of ischemia (marked decreases in the ratio of peak early [E] to peak atrial [A] filling velocity [E/A], in the ratio of early to atrial time-velocity integral [E-I/A(I)], in E, in E acceleration, and in total diastolic time-velocity integral) were compared with standard wall-motion analysis and ST-segment analysis during dobutamine stress echocardiography (DSE) in 17 anesthetized patients with CAD and 7 age-matched control patients at low risk of CAD. Results: All patients with CAD but no control patients showed new systolic wall-motion abnormalities and/or ST-segment changes. Decreases of > 10% in E/A and E-I/A(I) were found in 88% and 71% of the patients with CAD and in 71% and 100% of the control patients, respectively. These decreases were found during dobutamine infusion at as low as 10 mcg/kg/min in several control patients. None of the other studied Doppler indexes were found useful to detect ischemia. Conclusions: Doppler echocardiography of diastolic transmitral flow velocities is of no appreciable diagnostic value for detecting ischemia in anesthetized patients who receive dobutamine at 10-40 mcg/kg/min.