Comparison of local sine wave modeling with harmonic phase analysis for the assessment of myocardial strain

Purpose: To compare local sine-wave modeling (SinMod) with harmonic phase analysis (HARP), for assessment of left ventricular (LV) circumferential strain (epsilon cc) from tagged cardiovascular magnetic resonance images. Materials and Methods: Mid-ventricular spatial modulation of magnetization was performed in 60 participants (15 each with hypertrophic, dilated or ischemic cardiomyopathy and 15 healthy controls) at 1.5 Tesla. Global and segmental peak transmural epsilon cc were measured using HARP and SinMod. Repeated measurements were performed on 25% of examinations to assess observer variability. Effect of contrast was assessed in 10 additional patients. Results: SinMod showed a high level of agreement with HARP for global epsilon cc (mean difference -0.02, 95% limits of agreement -6.46 to 6.43%). Agreement was much lower for segmental epsilon cc. Both methods showed excellent observer agreement for global epsilon cc (intraclass correlation coefficient >0.75). Observer agreement for segmental epsilon cc was also excellent with SinMod, but was significantly lower with HARP. Analysis time was significantly shorter using SinMod. Pre- and postcontrast epsilon cc measurements were not significantly different using either technique, although postcontrast measurements showed greater variability with HARP. Conclusion: SinMod and HARP-based measurements of global epsilon cc have a high level of agreement, but segmental agreement is substantially lower. SinMod has generally lower observer variability, is faster and is less affected by contrast, but requires further validation. J. Magn. Reson. Imaging 2013;38:320-328. (c) 2012 Wiley Periodicals, Inc.