Comparison between cardiac magnetic resonance stress T1 mapping and [15O]H2O positron emission tomography in patients with suspected obstructive coronary artery disease

Aims To compare cardiac magnetic resonance (CMR) measurement of T1 reactivity (DT1) with [ 15O]H 2O positron emission tomography (PET) measurements of quantitative myocardial perfusion. ................................................................................................................................................................................................... Methods Forty-three patients with suspected obstructed coronary artery disease underwent [ 15O]H 2O PET and CMR at and results 1.5-T, including rest and adenosine stress T1 mapping (ShMOLLI) and late gadolinium enhancement to rule out presence of scar tissue. DT1 was determined for the three main vascular territories and compared with [ 15O]H 2O PET-derived regional stress myocardial blood flow (MBF) and myocardial flow reserve (MFR). DT1 showed a significant but poor correlation with stress MBF (R 2 = 0.04, P = 0.03) and MFR (R 2 = 0.07, P = 0.004). Vascular territories with impaired stress MBF (i.e. 15O]H 2O PET measurements of absolute myocardial perfusion. Stress T1 and DT1 are lower in vascular territories with reduced stress MBF but have poor accuracy for detecting impaired myocardial perfusion.