Dobutamine magnetic resonance imaging as a predictor of myocardial functional recovery after revascularisation

Objective-To assess the use of dobutamine magnetic resonance imaging (MRI) as a preoperative predictor of myocardial functional recovery after revascu larisation, comparing wall motion and radial wall thickening analyses by ob server and semi-automated edge detection. Patients-25 men with multivessel coronary disease and resting wall motion a bnormalities were studied with preoperative rest and stress MRI. Main outcome measures-Observer analysis for radial wall thickening was comp ared with a normal range, while wall motion analysis used a standard four F eint scale. Semi-automated analysis was performed using an edge detection a lgorithm. Segments displaying either improved or worsened thickening or mot ion with dobutamine were considered viable. Postoperative rest images were performed 3-6 months after coronary artery bypass grafting (CABG) for compa rison. Results-For observer analysis the values for sensitivity and specificity we re 50% and 72% for wall motion, with respective values of 50% and 68% for t hickening. With semi-automated edge detection the figures for motion were 6 0% and 73%, with corresponding values of 79% and 58% for thickening. Combin ing thickening and motion for the semi-automated method to describe any cha nge in segmental function yielded a sensitivity of 71% and specificity of 7 0%. Conclusions-Dobutamine MRI is a reasonably good predictor of myocardial fun ctional recovery after CABG. The use of semi-automated edge detection analy sis improved results.