Additive Value of Magnetic Resonance Coronary Angiography in a Comprehensive Cardiac Magnetic Resonance Stress-Rest Protocol for Detection of Functionally Significant Coronary Artery Disease A Pilot Study

Background— Cardiovascular magnetic resonance (CMR) myocardial perfusion imaging (MPI) is a state-of-the-art noninvasive modality for detection of myocardial ischemia and coronary artery disease. Magnetic resonance coronary angiography (MRCA) allows visualization of the coronary tree, but its incremental value as part of a CMR protocol including MPI and late gadolinium enhancement (LGE) is not well established. We aimed to evaluate the additive diagnostic value of a 3-dimensional whole-heart MRCA integration into a 1.5T CMR-MPI/LGE protocol for the detection of functionally significant coronary artery disease. Methods and Results— Forty-three symptomatic patients (61±8.3 years; 65% men) with suspected coronary artery disease and intermediate/high-pretest probability underwent CMR (including CMR-MPI, MRCA, and LGE) and x-ray invasive coronary angiography (XA) with fractional flow reserve evaluation. Diagnostic performances of MRCA, CMR-MPI/LGE, and MRCA+CMR-MPI/LGE integration were determined having XA+fractional flow reserve as standard for coronary artery disease (≥90% stenosis/occlusion or fractional flow reserve≤0.80 in vessels>2 mm). MRCA inclusion into the CMR protocol was associated with a mean increase of 7.9±4.69 (0–17.7) minutes in total examination duration (14%). On patient-based analysis, MRCA had 96% sensitivity, 68% specificity, positive predictive value of 79%, and negative predictive value of 93%. CMR-MPI/LGE had 79% sensitivity, 95% specificity, positive predictive value of 95%, and negative predictive value of 78%. Integration of MRCA with CMR-MPI/LGE further improved CMR performance to 96% sensitivity, 89% specificity, positive predictive value of 92%, and negative predictive value of 94%, with a global accuracy of 93%. Conclusions— In this intermediate/high-pretest population, integration of noncontrast-enhanced whole-heart MRCA nonsignificantly improved per-patient diagnostic accuracy of a comprehensive 1.5-T stress-rest CMR-MPI/LGE protocol at a cost of longer scanning times.