Comparision the value of detecting myocardial viability between low dose dobutamine stress MRI and echocardiography

Objective To Compare the diagnostic value between low dose dobutamine stress transthrotic echocardiography and low dose dobutamine stress MRI in detecting myocardial viability of chronic myocardial infarction.Methods Rest and low dose dobutamine(5,10 μg ·kg-1·min-1)stress transthrotic echocardiography and cine-MRI were performed in 30 patients with chronic myocardial infarction.24 patients underwent successful revascularization and 10 of them underwent another rest cine-MRI study to assess segmental myocardial functional recovery.Left ventricular were divided into 16 segments,the criteria of viability in different techniques is :MRI:dobutamine induced systolic wall thickenning was≥2 mm in akinetic or diskinetic segments at rest;Echocardiography:wall motion score reduced at least 1 after dobutamine stress in akinetic or diskinetic segments at rest.Results One hundren and eight segments showed wall motion abnormalities of 30 patients,65 and 56 segments shows positive reaction,43 and 52 segments shows negativereaction in MRI and echocardiography after dobutamine stress respectively.Kappa value of the two techniques is 0.75,concordance in both techniques is 88%.Twenty-four segments showed functional recovery,14 segments remained dysfunction 3—6 months after revascularization.the sensitivity 、specificity and accuracy of detecting myocardial viability in chronic myocardial infarction in MRI and echocardiography is 95.8% vs 79.2%(P0.05),85.7% vs 85.7%(P0.05),92.1% vs 81.6%(P0.05)respectively.The sensitivity and accuracy of MRI is a little higher.Conclusion The ability of detecting myocardial viability by both low dose dobutamine stress transthrotic echocardiography and low dose dobutamine stress MRI is similer,the sensitivity and accuracy of MRI is a little higher.