Characterization of cardiac amyloidosis using cardiac magnetic resonance fingerprinting

BACKGROUND: Cardiac amyloidosis (CA) is an infiltrative cardiomyopathy with poor prognosis absent appropriate treatment. Elevated native myocardial T(1) and T(2) have been reported for CA, and tissue characterization by cardiac MRI may expedite diagnosis and treatment. Cardiac Magnetic Resonance Fingerprinting (cMRF) has the potential to enable tissue characterization for CA through rapid, simultaneous T(1) and T(2) mapping. Furthermore, cMRF signal timecourses may provide additional information beyond myocardial T(1) and T(2). METHODS: Nine CA patients and five controls were scanned at 3T using a prospectively gated cMRF acquisition. Two cMRF-based analysis approaches were examined: (1) relaxometric-based linear discriminant analysis (LDA) using native T(1) and T(2), and (2) signal timecourse-based LDA. The Fisher coefficient was used to compare the separability of patient and control groups from both approaches. Leave-two-out cross-validation was employed to evaluate the classification error rates of both approaches. RESULTS: Elevated myocardial T(1) and T(2) was observed in patients vs controls (T(1) 1395±121 vs 1240±36.4 ms, p