LOW-DOSE DOBUTAMINE STRESS TEST FOR THE EVALUATION OF CARDIAC-FUNCTION USING ULTRAFAST COMPUTED-TOMOGRAPHY

High dose-dobutamine (DOB) has been previously used as a pharmacologic al stress test to evaluate wall motion abnormalities. As a result, rec ent stress echocardiography with low-dose DOB has been reported to be valuable for investigating stunned myocardium after thrombolysis. Howe ver, echocardiography requires an operator's skill and experience to e valuate wall motion abnormalities which are subjectively determined by the observer. In contrast, ultrafast computed tomography (UFCT) does not necessarily require extreme technical skill and experience. To eva luate the feasibility of stress UFCT with low-dose DOB, we scanned 10 normal subjects along the short-axis by 8-slice-multicine mode. After scanning at rest for baseline, we scanned during the administration of 4 and 8 mug/kg/min of DOB, respectively, for 5 min. Ejection fraction , contraction, and thickening were higher during 8 mug/kg/min of DOB t han during 4 mug/kg/min of DOB and baseline, while the above values we re higher during 4 mug/kg/min of DOB than during baseline (p < 0.01). It was possible to detect changes of cardiac function and wall motion due to low-dose DOB by UFCT. We therefore conclude that UFCT is a reli able modality for evaluating cardiac function and wall motion for low- dose DOB stress test because of its excellent spatial and contrast res olution.