Usefulness of radial strain mapping by multidetector computer tomography to quantify regional myocardial function in patients with healed myocardial infarction.

We introduce and evaluate strain mapping by multidetector computer tomography as a new noninvasive method for assessment of myocardial function. In patients (n = 16) with healed myocardial infarction, peak systolic radial strain was measured by automated pixel pattern matching analysis of multiple left ventricular 64-slice multidetector computer tomographic short-axis recordings. For comparison, radial strain and myocardial infarct extent were measured by tagged magnetic resonance imaging (MRI) and late enhancement MRI, respectively. In a linear mixed model analysis, myocardial infarct extent was a strong predictor of segmental strain by multidetector computer tomography (beta = -0.44, p <0.0001). Strain was significantly different among noninfarcted (0%), nontransmurally infarcted (0% to 50%), and transmurally infarcted (>50%) segments (p <0.001) and between infarcted and noninfarcted border zone segments (p <0.001). There was a close relation between strain by multidetector computer tomography and by tagged MRI (mean difference -7.4 +/- 11.7%, r = 0.68, p <0.0001). Mean time-to-peak systolic strain was 324 +/- 42 ms by multidetector computer tomography and 335 +/- 56 ms by tagged MRI (mean difference 11 +/- 40 ms). In conclusion, to our knowledge this is the first study to demonstrate that regional myocardial function can be quantified by multidetector computer tomographic imaging, indicating that assessment of radial strain by multidetector computer tomography might be a useful tool in the evaluation of patients with cardiovascular diseases.