Detection of viable myocardium by dobutamine stress tagging magnetic resonance imaging with three-dimensional analysis by automatic trace method

The present study attempted to detect the viability of myocardium by quanti tative automatic 3-dimensional analysis of the improvement of regional wall motion using an magnetic resonance imaging (MRI) tagging method. Twenty-tw o subjects with ischemic heart disease who had abnormal wall motion on echo cardiography at rest were enrolled. All patients underwent dobutamine stres s echocardiography (DSE), coronary arteriography and left ventriculography. The results were compared with those of 7 normal volunteers. MRI studies w ere done with myocardial tagging using the spatial modulation of magnetizat ion technique. Automatic tracing with an original program was performed, an d wall motion was compared before and during dobutamine infusion. The evalu ation of myocardial viability with MRI and echocardiography had similar res ults in 19 (86.4%) of the 22 patients: 20 were studied by positron emission tomography or thallium-201 single photon emission computed tomography for myocardial viability, or studied for improvement of wall motion following c oronary intervention. The sensitivity of dobutamine stress MRI (DSMRI) with tagging was 75.9% whereas that of DSE was 65.5%. The specificity of DSMRI was 85.7% (6/7) and that of DSE was 100% (7/7). The accuracy of DSMRI was 7 7.8% (28/36) and that of DSE 72.2% (26/36). DSMRI was shown to be superior to DSE in terms of evaluation of myocardial viability.