Combined use of low-dose dobutamine echocardiography and myocardial contrast echocardiography to assess myocardial viability

doi:10.3969/j.issn.1005-2194.2001.05.010

Abstract：Objective To predict prospectively viable myocardium withcombined use of low-dose dobutamine echocardiography(LDDE) and myocardial contrast echocardiography(MCE).Methods 24 patients with myocardial infarction(MI) underwent resting MCE with intermittent harmonic,pulsed inversion imaging,LDDE and repeated resting echocardiography at 3-month follow-up and regional function recovery was analyzed.Estimations of myocardial contrast score(MCS) and wall motion score(WMS) were made by visual analysis in 16-segment model.MCS was graded as 1,homogeneous opacification;0.5,patchy pattern;0,no opacification.WMS was graded as 1,normal;2,hypokinesis;3,akinesis;4,dyskinesis. Results MCS 1(49.4%) and 0.5(50.6%) segments positively responded to LDDE had regional function recovery;MCS 0.5(9.5%) and 0(90.5%) segments revealed irreversible dysfunction.Of these segments 13.3% had positive and 86.7% negative to LDDE at 3-month follow-up.The sensitivity,specificity and accuracy in predicting viable myocardium were 86.0%,86.7% and 86.4% by LDDE;100%,89.7% and 94.6% by MCE;86.1%,100% and 94.0% by combination of LDDE and MCE respectively. Conclusions Microvascular anatomic and functional integrity is a fundamental requisite for ensuring viability after MI.Most of normal or decreased perfusion segments positively responded to LDDE demonstrate contractile reserve,while decreased or no perfusion segments with negative response to LDDE show irreversible dysfunction.The integration of LDDE with MCE can improve specificity and accuracy in detecting viable myocardium.