Singular Value Decomposition Applied to Cardiac Strain from MR Imaging for Selection of Optimal Cardiac Resynchronization Therapy Candidates.

PURPOSE: To use singular value decomposition (SVD) in heart failure (HF) to reveal primary spatiotemporal strain patterns in the left ventricle (LV), then develop and test a time-independent metric of cardiac dyssynchrony on the basis of the circumferential uniformity ratio estimate (CURE) computed with SVD (CURE-SVD) in both a canine model of HF with or without left bundle branch block (LBBB) and a clinical cohort referred for cardiac resynchronization therapy (CRT).
MATERIALS AND METHODS: The research was approved by the institutional review board and conformed with HIPAA requirements. All subjects provided informed consent. In both the canine model (n = 13) and the clinical cohort (80 CRT candidates; mean age, 65.2 years; range, 18.5-86.9 years), regional strains were derived by using cardiac magnetic resonance (MR) displacement encoding with stimulated echoes. CURE-SVD was compared with the standard CURE (averaged over systolic phases). Statistical methods included the Wilcoxon rank-sum test, Hodges-Lehmann estimator, Bland-Altman test, multivariable logistic regression, and receiver operating characteristic analysis.
RESULTS: In the canine model, the median difference in CURE-SVD (range, 0-1) for LBBB-HF group versus narrow-QRS-HF group (-0.40; 95% confidence interval [CI]: -0.79, -0.31) was similar to that for CURE (-0.43; 95% CI: -0.72, -0.34]). In 80 CRT candidates, CURE-SVD and CURE were highly correlated (r = 0.90; P < .0001). The multivariable model for CRT response with CURE-SVD demonstrated excellent performance without the need for time averaging over cardiac phases (area under the receiver operating characteristic curve = 0.96, P < .0001).
CONCLUSION: SVD of circumferential strain in HF identifies primary LV spatiotemporal contraction patterns with minimal user input, while the time-independent CURE-SVD parameter has excellent performance in a canine model of dyssynchrony and is strongly associated with CRT response in patients with HF. (©)RSNA, 2015.