T1-Mapping in Daily Cardiac Magnetic Resonance Imaging Practice: Combined Use of Native T1 and Extracellular Volume Quantification

Abstract

T1-Mapping in Daily Cardiac Magnetic Resonance Imaging Practice: Combined Use of Native T1 and Extracellular Volume Quantification Introduction: Dual T1-mapping allows for a comprehensive assessment of myocardial tissue by combining detection of edema in the native scan and quantification of extracellular volume (ECV) after administration of Gadolinium (Gd). Recent studies proved the diagnostic value of T1-mapping in different pathologies. The aim of this study was, to evaluate the practicability and robustness of T1-mapping in assessing common pathologies in daily cardiac magnetic resonance (CMR) practice. Methods: From October 2012 to October 2013, we investigated 136 consecutive patients undergoing clinically indicated CMR examination by performing additional T1-mapping measurements. We used a Modified-Look-Locker-Inversion-Recovery (MOLLI) sequence with 3 inversion pulses and a 4-(1)-3-(1)-2 readout pattern. For extracellular volume calculation a second scan was performed 10min. after administration of 0.2mmol/kg body weight gadopentetate dimeglumine. Diagnosis was based on clinical information and standard CMRsequences comprising native T2-weighted dark-blood turbo spin echo (TSE) sequences, pre- and early post-Gd T1-weighted darkblood TSE sequences and Late Gadolinium Enhancement. The study population comprised a control group, patients with acute and chronic myocarditis, patients with acute and chronic infarction, patients with dilated and hypertrophic cardiomyopathy, patients with aortic stenosis and patients with amyloidosis or sarcoidosis. Results: Native T1 showed a significant difference when compared with a control in acute myocarditis, acute myocardial infarction, hypertrophic and dilated cardiomyopathy, and amyloidosis. ECV showed significant differences to the control group in all cohorts of pathologies. Particularly high native T1 values were observed in acute myocarditis, acute myocardial infarction, hypertrophic cardiomyopathy and amyloidosis, a high ECV was found in acute and chronic myocarditis, acute and chronic myocardial infarction, sarcoidosis and amyloidosis. Conclusion: Native T1-mapping and ECV correlated well with myocardial alterations in commonly diagnosed cardiac disorders. It proved reliable and robust in daily clinical practice and allows for a good differentiation between normal findings and common pathological CMR diagnoses. The combined use of native T1 and ECV quantification is a promising approach for comprehensive assessment of the myocardium and may improve diagnostic accuracy of CMR in myocardial disease.