Background: Dobutamine stress magnetic resonance (DSMR) imaging has emerged as a valuable tool for the detection of inducible wall motion abnormalities. The role of perfusion imaging during DSMR is not well defined. We examined whether the addition of myocardial perfusion imaging during DSMR provides incremental benefit for the evaluation of coronary artery disease.
Methods and results: DSMR was combined with perfusion imaging in 455 consecutive patients who were scheduled for clinically indicated invasive coronary angiography. Perfusion images were acquired in 3 standard short-views at rest and during maximum dobutamine-atropine stress. Wall motion and perfusion images were interpreted sequentially, blinded to other data. Significant (> or =70%) stenoses were present in 285 patients on invasive coronary angiography. The use of DSMR combined with perfusion imaging versus DSMR increased sensitivity (91% versus 85%, P=0.001), but not specificity (70% versus 82%, P=0.001), resulting in identical overall diagnostic accuracy (84% versus 84%, P=NS; Youden index 0.61 versus 0.67). DSMR combined with perfusion imaging enabled the correct diagnosis of coronary artery disease in an additional 13% of DSMR-negative patients at the cost of 11% more false-positive cases.
Conclusions: The addition of perfusion imaging during DSMR improves sensitivity for the diagnosis of coronary artery disease but does not enhance overall diagnostic accuracy because of a concomitant decrease in specificity.