Influence of image quality on the diagnostic accuracy of dobutamine stressmagnetic resonance imaging in comparison with dobutamine stress ethocardiography for the non-invasive detection of myocardial ischemia

The analysis of wall motion abnormalities with dobutamine stress echocardio graphy is an established method for the detection of myocardial ischemia. W ith ultrafast magnetic resonance tomography, the application of identical s tress protocols as used for echocardiography is possible. In 208 consecutive patients (147 Mt 61 F) with suspected coronary artery di sease, dobutamine stress echocardiography partially using harmonic imaging and dobutamine stress magnetic resonance tomography (DSMR) were performed p rior to cardiac catheterization. DSMR images were acquired during short bre ath holds in 3 short axis-, a 4-, and a 2-chamber view using a turbo gradie nt echo technique. Patients were examined at rest and during a standard dob utamine-atropine scheme until submaximal heart rate was reached. Regional w all motion was assessed in a 16 segment model. Significant coronary heart d isease was defined as angiographic greater than or equal to 50 % diameter s tenosis. With DSMR, significantly more patients yielded very good (69 %) or good (13 %) image quality in comparison with dobutamine stress echocardiography (20 % and 31 %, p < 0.05). Moderate image quality occurred in 16 % with MR and 41 % with dobutamine stress echocardiography (p < 0.05), 2 % and 8 % were non-diagnostic. With each technique 18 patients could not be examined (DSE: emphysema: 10, adipositas: 8; DSMR: claustrophobia: 11, adipositas: 6, con traindication: 1). Four patients did not reach target heart rate. In 107 pa tients, significant coronary artery disease was found. With DSMR sensitivit y was 88.7 % (dobutamine stress echocardiography: 74.3 %; p < 0.05) and spe cificity 85.7 % (dobutamine stress echocardiography: 69.8 %; p < 0.05). Thi s difference was most pronounced in the group with moderate echocardiograph ic image quality. High dose DSMR is superior to dobutamine stress echocardiography and can re place this technique especially in patients with moderate echocardiographic image quality.