Contrast magnetic resonance imaging in the assessment of myocardial viability in patients with stable coronary artery disease and left ventricular dysfunction

Background-The utility of contrast MRI for assessing myocardial viability i n stable coronary artery disease (CAD) with left ventricular dysfunction is uncertain. We therefore performed cine and contrast MRI in 24 stable patie nts with CAD and regional contractile abnormalities and compared MRI findin gs with rest-redistribution Tl-201 imaging and dobutamine echocardiography. Methods and Results-Delayed MRI contrast enhancement patterns were examined from 3 to 15 minutes after injection of 0.1 mmol/kg IV gadolinium diethyle netriamine pentaacetic acid (Gd-DTPA). Comparable MRI and Tl-201 basal and midventricular short-axis images were subdivided irate 6 segments. Segments judged nonviable by quantitative and qualitative assessment of Tl-201 scan s showed persistent, systematically greater MRI contrast signal intensity t han segments judged viable (P less than or equal to 0.002). Delayed contras t hyperenhancement also occurred in segments judged nonviable by dobutamine echocardiography (P less than or equal to 0.03). The presence or absence o f hyperenhancement correlated most closely with nonviability and viability, respectively, in segments that were akinetic or dyskinetic under resting c onditions (83% concordance with Tl-201 in both cases). In segments with res ting hypokinesis, 58% of segments showing hyperenhancement were judged viab le by Tl-201 and may have represented an admixture of scar tissue and viabl e myocardium. Conclusions-Delayed (by 3 to 15 minutes) hyperenhancement of Gd-DTPA contra st-enhanced MRI images occurs frequently in dysfunctional areas of the left ventricle in patients with stable CAD. Hyperenhancement is associated with nonviability by rest-redistribution Tl-201 scintigraphy and dobutamine ech ocardiography, particularly in regions exhibiting resting akinesis/dyskines is. The absence of hyperenhancement correlates with radionuclide and echoca rdiographic determinations of viability, regardless of resting contractile function.