Quantitative circumferential strain analysis using adenosine triphosphate-stress/rest 3-T tagged magnetic resonance...

We evaluated whether a quantitative circumferential strain (CS) analysis using adenosine triphosphate (ATP)-stress/rest 3-T tagged magnetic resonance (MR) imaging can depict myocardial ischemia as contractile dysfunction during stress in patients with suspected coronary artery disease (CAD). We evaluated whether it can differentiate between non-ischemia, myocardial ischemia, and infarction. We assessed its diagnostic performance in comparison with ATP-stress myocardial perfusion MR and late gadolinium enhancement (LGE)-MR imaging.

In 38 patients suspected of having CAD, myocardial segments were categorized as non-ischemic (n=485), ischemic (n=74), or infarcted (n=49) from the results of perfusion MR and LGE-MR. The peak negative CS value, peak circumferential systolic strain rate (CSR), and time-to-peak CS were measured in 16 segments.

A cutoff value of -12.0% for CS at rest allowed differentiation between infarcted and other segments with a sensitivity of 79%, specificity of 76%, accuracy of 76%, and an area under the curve (AUC) of 0.81. Additionally, a cutoff value of 477.3ms for time-to-peak CS at rest allowed differentiation between infarcted and other segments with a sensitivity of 61%, specificity of 91%, accuracy of 88%, and an AUC of 0.75. The differences in CS values between ATP-stress and rest conditions (ΔCS) in non-ischemic segments (median [first quartile, third quartile] -1.7 [-3.2, -0.1] %) were smaller than in segments with ischemia (+1.1 [+0.3, +2.3] %, p<0.001). A cutoff value of +0.3% for the ΔCS value could differentiate segments with ischemia from non-ischemic segments with a sensitivity of 75%, a specificity of 82%, an accuracy of 82%, and an AUC of 0.86.

Circumferential strain analysis using tagged MR can quantitatively assess contractile dysfunction in ischemic and infarcted myocardium.