Cardiac magnetic resonance myocardial perfusion imaging for detection of functionally significant obstructive coronary artery disease: a prospective study

Background: Cardiac magnetic resonance myocardial perfusion imaging (CMR-MPI) is considered a state of the art non-invasive modality for the detection of reversible ischemia. Recent studies have shown its utility in the diagnosis of coronary artery disease (CAD) and superiority over other established techniques. However, only a few studies compared CMR-MPI against the invasive standard including fractional flow reserve (FFR) and clinical validation in non-specialized centers is scarce. The aim of this study was to validate CMR-MPI in a real-world clinical environment and to test its diagnostic accuracy in symptomatic patients with suspected CAD versus FFR as the reference standard of functionally significant disease.

Methods and results: 103 symptomatic consecutive patients (62 ± 8.0 years, 66% males) with suspected CAD and intermediate or high probability of disease underwent sequential CMR and invasive coronary angiography (XA). The CMR protocol included stress-rest adenosine perfusion, SSFP cine imaging and late-enhancement imaging. Functionally significant CAD was defined as occlusive/sub-occlusive stenoses on XA or non-occlusive stenoses with a FFR measurement of <0.80 in vessels >2mm. On a patient-based model, CMR-MPI had sensitivity, specificity, positive and negative predictive values of 89%, 88%, 85%, and 91%, respectively, with a global accuracy of 88%. On a vessel-based analysis, these values were 80%, 93%, 79% and 94%, respectively, with a global accuracy of 90%.

Conclusions: CMR-MPI had a very high accuracy for detection of functionally significant CAD as assessed by FFR in patients with intermediate to high pretest probability.