Contrast enhanced electron beam computed tomography to analyse the coronary arteries in patients after acute myocardial infarction

Objective-To evaluate the accuracy of contrast enhanced electron beam compu ted tomography (EBCT) after acute myocardial infarction in determining pate ncy of the infarct related artery and detecting high grade stenoses and occ lusions in the coronary vessels. Design-Case study using blinded comparison with invasive coronary angiograp hy. Patients-36 patients (mean age 53 years) 4-70 days after acute myocardial i nfarction. Interventions-The patients were studied by EBCT and invasive coronary angio graphy. For EBCT, 50 axial images of the heart (3 mm slice thickness) were acquired. They were triggered by the ECG during breath holding, after intra venous injection of contrast agent. The original images, surface reconstruc tions, and maximum intensity projections were evaluated for the presence of high grade stenoses and occlusions of the coronary arteries. Main outcome measures-EBCT results were compared with invasive coronary ang iography. Results-Of a total of 144 coronary arteries (left main, left anterior desce nding, left circumflex, and right coronary artery in 36 patients), 29 (20%) were unevaluable by EBCT In the remaining arteries, 33 of 36 high grade le sions were correctly detected (92% sensitivity). Specificity was also 92% ( 73/79). Patency of the infarct related artery was correctly detected in 15 of 16 cases (94%). Five of the 14 occluded infarct related arteries (35%) w ere mistaken as stenotic but patent, and six could not be assessed. Conclusions-EBCT is very accurate in detecting significant coronary artery lesions in patients after acute myocardial infarction, but differentiation between occluded and patent infarct related arteries is currently unreliabl e.