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Figure 1 Quantification of Circumferential Mechanical Dyssynchrony from MR-MT Strain Map
Calculation of the circumferential uniformity ratio estimate (CURE) for mechanical dyssynchrony using Fourier analysis with extreme examples of spatial distribution of strain for synchrony (straight line) versus dyssynchrony (sine wave pattern). S0 is the zero-order or constant term of the Fourier transform, and S1 is the first-order term, representing low frequency changes at a given time. The CURE for a given short-axis slice is generated first by determining instantaneous circumferential strains at 24 equally spaced segments in a short-axis slice at each time point, then subjecting this strain v. segment data to Fourier analysis with determination of the ratio of first- to zero-order power. MR-MT = magnetic resonance-myocardial tagging.
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