title: Low-dose dobutamine stress test for the evaluation of cardiac function using ultrafast computed tomography.
abstract: High dose-dobutamine (DOB) has been previously used as a pharmacological stress test to evaluate wall motion abnormalities. As a result, recent stress echocardiography with low-dose DOB has been reported to be valuable for investigating stunned myocardium after thrombolysis. However, echocardiography requires an operator's skill and experience to evaluate 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 evaluate 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 micrograms/kg/min of DOB, respectively, for 5 min. Ejection fraction, contraction, and thickening were higher during 8 micrograms/kg/min of DOB than during 4 micrograms/kg/min of DOB and baseline, while the above values were higher during 4 micrograms/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 reliable modality for evaluating cardiac function and wall motion for low-dose DOB stress test because of its excellent spatial and contrast resolution.
authors.affiliation: First Department of Internal Medicine, Shiga University of Medical Science, Ohtsu, Japan.
authors.forename: O
authors.initials: O
authors.lastname: Yamaoka
authors.forename: H
authors.initials: H
authors.lastname: Fujioka
authors.forename: T
authors.initials: T
authors.lastname: Haque
authors.forename: Y
authors.initials: Y
authors.lastname: Nakamura
authors.forename: K
authors.initials: K
authors.lastname: Mitsunami
authors.forename: M
authors.initials: M
authors.lastname: Kinoshita
authors.forename: K
authors.initials: K
authors.lastname: Murata
authors.forename: R
authors.initials: R
authors.lastname: Morita
mesh_terms: D000293:Adolescent; D000328:Adult; D004280:Dobutamine / Q000008:administration & dosage / Q000494:pharmacology; D005080:Exercise Test / Q000379:methods; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects; D017202:Myocardial Ischemia / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology; D014057:Tomography, X-Ray Computed
chemical_list: D004280:Dobutamine