Dilated Cardiomyopathy: Normalized Multiparametric Myocardial Strain Predicts Contractile Recovery

Abstract

Background Left ventricular (LV) contractile injury in dilated cardiomyopathy (DCM) may occur in a consistently heterogeneous distribution, suggesting that early injury “sentinel” regions may have prognostic significance. Heightened surveillance of these regions with high-resolution contractile metrics may predict recovery in DCM. Methods Multiple 3D strain parameters were calculated at each of 15,300 LV grid-points from systolic displacement data obtained from cardiac MRI in 124 test subjects. In 24 DCM patients, z-scores for two strain parameters at each grid-point were calculated by comparison of patient-specific strain values to respective point-specific mean and standard deviation values from a normal human strain database (n=100). Multiparametric strain z-scores were averaged over 6 LV regions at basilar, mid, and apical levels (18 sub-regions). DCM patients were stratified into 3 groups based on a blinded review of clinical contractile recovery (complete[n=7]; incomplete[n=7]; none[n=10]). Results Basilar-septal sub-regions were consistently heavily injured. Basilar-septal z-scores were significantly larger (worse) than those for the rest of the LV (2.73±1.27 vs 2.22±0.83; p=0.011) and lateral wall (2.73±1.27 vs 1.44±0.72; p<0.001). All patients with sentinel region average multiparametric strain z-scores <2 standard deviations (n=6) experienced complete recovery, while 17/18 DCM patients with z-scores >2 standard deviations experienced incomplete or no contractile recovery. Conclusions Contractile injury in DCM is heterogeneous with basilar-septal regions injured more than lateral regions. The targeting of early-injury sentinel regions for heightened surveillance with high-resolution metrics of micro-regional contractile function may accurately predict recovery on medical therapy. A 2 standard deviation z-score threshold may predict contractile recovery.

Inotropic and lusitropic effects of incremental doses of dobutamine in dogs with right ventricular apical pacing‐induced cardiac dysfunction

“…However, E′ is modified by end‐diastolic pressure, hence, it might have influenced E/ ratio. LV lengthening changes observed only at the septal mitral annulus after 8 weeks of RVAP suggested early signal injury as previously described in a study showing abnormal segmental contraction localized at septal (vs. lateral) region and its predictive value for therapeutic response (Henn et al., ).…”

Strain Values of Left Ventricular Segments Reduce Non-homogeneously in Dilated Cardiomyopathy with Moderately and Severely Deteriorated Heart Function Assessed by MRI Tissue Tracking Imaging

“…Mid Fiber geometry of the left ventricle is smooth and has a right-handed helical orientation in the subendocardium, circumferential orientation in the midwall, and lefthanded helical orientation in the subepicardium. [18][19][20] Henn, et al 21) reported that contractile injury in non-ischemic DCM occurs asynchronously in various segments of the left ventricle accompanied with cardiac function deterioration, which suggested the heterogeneity of strain injury. In the progress of DCM, left ventricle dilatates from oval to spherical, while orientation of LV fibers changes from oblique to horizontal, especially in the apex segment.…”

Role of Cardiac Imaging: Cardiac Magnetic Resonance and Cardiac Computed Tomography

“…In DCM, the occurrence of nonhomogeneous fibrous substitution of cardiomyocytes may alter mechanical activity in these areas [92], thus leading to a heterogeneous compromise of regional contractile function [93]. Myocardial deformation analysis can supply useful information for the evaluation of global and regional myocardial function [94,95].…”