Layer-Specific Strain Analysis in Patients with Dilated Cardiomyopathy

Abstract

Background/objectives: This study aimed to evaluate layer-specific strain according to etiology and assess whether subtle changes in longitudinal and circumferential layer strain are involved in predicting cardiac mortality during a two-year follow-up in patients with dilated cardiomyopathy admitted with heart failure decompensation.

Methods: 97 patients with dilated cardiomyopathy and a left ventricle ejection fraction ≤ 40% were recruited, 51 with ischemic and 46 with nonischemic etiologies. Conventional and two-dimensional speckle-tracking echocardiography (2D-STE) were conducted in dilated cardiomyopathy patients with a compensated phase of heart failure before discharge. Layer-specific longitudinal and circumferential strain was assessed from the endocardium, mid-myocardium, and epicardium by two-dimensional (2D) speckle-tracking echocardiography. The gradient between the endocardium and epicardium was calculated.

Results: Patients with nonischemic etiology of dilated cardiomyopathy presented smaller values of global and layer strain than patients in the ischemic group. GLS, GLSend, GLSend-GLSepi, CSPMend, CSPMend-CSPMepi, CSAP, CSAPend, and CSAPend-CSAPepi were the parameters with statistically significant decreased values in non-survivors compared with survivors. In multivariate analysis, only CSPMend showed an independent value in predicting mortality at two-year follow-up. Receiver operator curve analysis provided CSPMend of -10.8% as a cut-off value with a sensitivity of 80% and specificity of 61.05% in identifying the dilated cardiomyopathy and heart failure patients with a risk of death at two-year follow-up.

Conclusions: GLS, GCS, and layer-specific strain analysis showed decreased values in nonischemic compared with ischemic dilated cardiomyopathy and also in non-survivors compared with survivors. CSPMend was the most sensitive strain parameter to identify patients with increased mortality risk at two-year follow-up.

Keywords: dilated cardiomyopathy; layer-specific strain analysis; outcome.

Figure 1

Layer-specific longitudinal strain analysis. (a) Apical 3-chamber view. (b) Apical 4-chamber view. (c) Apical three-chamber view. (d) Bulls-eye display of layers of strain.

Figure 2

Layer-specific circumferential strain analysis at the level of mitral valve.

Figure 3

Layer-specific circumferential strain analysis at the level of papillary muscle.

Figure 4

Layer-specific circumferential strain analysis at the apical level.

Figure 5

Boxplots of strain parameters in survivors vs. non-survivors. GLS—mid-layer longitudinal strain; GLSendendocardium longitudinal strain; GLSend-GLSepi—the gradient between endocardium longitudinal strain and epicardium longitudinal strain; CSMV—mid-layer circumferential strain at the level of the mitral valve; CSMVend—endocardium circumferential strain at the level of the mitral valve; CSMVend-CSMVepi—the gradient between endocardium circumferential strain and epicardium circumferential strain at the level of the mitral valve; CSPM—mid-layer circumferential strain at the level of the papillary muscles; CSPMend—endocardium circumferential strain at the level of the papillary muscles; CSPMend-CSPMepi—the gradient between endocardium circumferential strain and epicardium circumferential strain at the level of the papillary muscles; CSAP—mid-layer circumferential strain at the apical level; CSAPend—endocardium circumferential strain at the apical level; CSAPend-CSAPepi—the gradient between endocardium circumferential strain and epicardium circumferential strain at the apical level.

Figure 6

ROC curve analysis to identify sensitivity and specificity of CSPMend of −10.1% as an incremental factor to predict two-year mortality in patients with DCM and HF.

Figure 7

Power analysis report.