Dobutamine stress echocardiography
Initial dobutamine infusion is at low dose: 10 micrograms/kg/min (ten micrograms per kilogram body weight per minute)
High dose dobutamine infusion is given at: 20 micrograms/kg/min (twenty micrograms per kilogram body weight per minute)
Ischemic, but viable myocardium will show improvement in wall motion at low dose dobutamine with worsening at high dose dobutamine infusion. There is will be no such response for scarred myocardium which is non viable and it will show akinesia.
Wall motion scoring is graded as follows:
Normally contracting segment: 1
Hypokinetic segment: 2
Akinetic segment: 3
Dyskinetic segment: 4
Wall motion score index (WMSI) can be calculated as an average score of all the visualized segments.