Layer-specific strain in patients with heart failure using cardiovascular magnetic resonance: not all layers are the same

Abstract

Background Global longitudinal strain (GLS), most commonly measured at the endocardium, has been shown to be superior to left ventricular (LV) ejection fraction (LVEF) for the identification of systolic dysfunction and prediction of outcomes in heart failure (HF). We hypothesized that strains measured at different myocardial layers (endocardium = ENDO, epicardium = EPI, average = AVE) will have distinct diagnostic and predictive performance for patients with HF. Methods Layer-specific GLS, layer-specific global circumferential strain (GCS) and global radial strain (GRS) were evaluated by cardiovascular magnetic resonance imaging (CMR) feature tracking in the Alberta HEART study. A total of 453 subjects consisted of healthy controls (controls, n = 77), at-risk for HF (at-risk, n = 143), HF with preserved ejection fraction (HFpEF, n = 87), HF with mid-range ejection fraction (HFmrEF, n = 88) and HF with reduced ejection fraction (HFrEF, n = 58). For outcomes analysis, CMR-derived imaging parameters were adjusted with a base model that included age and N-terminal prohormone of b-type natriuretic peptide (NT-proBNP) to test their independent association with 5-year all-cause mortality. Results GLS_EPI distinguished all groups with preserved LVEF (controls − 16.5 ± 2.4% vs. at-risk − 15.5 ± 2.7% vs. HFpEF − 14.1 ± 3.0%, p < 0.001) while GLS_ENDO and all GCS (all layers) were similar among these groups. GRS was reduced in HFpEF (41.1 ± 13.8% versus 48.9 ± 10.7% in controls, p < 0.001) and the difference between GLS_EPI and GLS_ENDO were significantly larger in HFpEF as compared to controls. Within the preserved LVEF groups, reduced GRS and GLS_EPI were significantly associated with increased LV mass (LVM) and LVM/LV end-diastolic volume EDV (concentricity). In multivariable analysis, only GLS_AVE and GRS predicted 5-year all-cause mortality (all ps < 0.05), with the strongest association with 5-year all-cause mortality by Akaike Information Criterion analysis and significant incremental value for outcomes prediction beyond LVEF or GLS_ENDO by the likelihood ratio test. Conclusion Global strains measured on endocardium, epicardium or averaged across the wall thickness are not equivalent for the identification of systolic dysfunction or outcomes prediction in HF. The endocardium-specific strains were shown to have poorest all-around performance. GLS_AVE and GRS were the only CMR parameters to be significantly associated with 5-year all-cause mortality in multivariable analysis. GLS_EPI and GRS, as well as the difference in endocardial and epicardial strains, were sensitive to systolic dysfunction among HF patients with normal LVEF (> 55%), in whom lower strains were associated with increased concentricity.

Evaluation of left ventricular systolic function in patients with acute ST segment elevation myocardial infarction treated by Tongxinluo after percutaneous coronary intervention by tissue mitral annulus displacement technique

“…GLS can more sensitively re ect changes in left ventricular systolic function than GCS and LVEF, which is consistent with the results of Teraguchi I, et al [20]. This may be because the inner myocardium is more sensitive to myocardial injury, it is located at the distal end of the coronary artery, with abundant microvessels and less effective collateral circulation, and the longitudinal myocardium is easily damaged after PCI [21]. Therefore, since hypokinesia of the long axis of the myocardium becomes the rst manifestation, GLS can sensitively re ect the changes in left ventricular systolic function [22].…”

13 N-ammonia PET-derived right ventricular longitudinal strain and myocardial flow reserve in right coronary artery disease

“…First, the contribution of the longitudinal direction for myocardial contraction was greater in the RV than in the LV. In the LV myocardium, contractions of endocardial, middle, and epicardial layers produce the long axis and short axis motions, as well as a twisting motion corresponding to systemic circulation [19][20][21][22]. On the other hand, in the RV myocardium, two thin myocardial layers are responsible for pulmonary circulation, mainly long-axis contraction [23,24].…”

Regional Strain Score as Prognostic Marker of Cardiovascular Events From the Multi-Ethnic Study of Atherosclerosis (MESA)

“…Peak regional systolic Ecc was determined in 16 segments from three LV short-axis slices at the basal, mid-ventricular, and apical levels according to the model of the American Heart Association (24). For each segment, Ecc was determined in the sub-endocardial, mid-wall, and sub-epicardial layers (11,17). The intraclass correlation coefficients for inter-observer and intra-observer agreement for peak systolic mid-wall Ecc were 0.80 and 0.84, respectively, in studies with good tag persistence, and 0.74 and 0.82, respectively, in those with fair tag persistence (22).…”

“…However, few studies have assessed the long-term prognostic value of the LV regional Ecc assessed by CMR tagging compared to LVEF, traditional risk factors, and global Ecc in asymptomatic participants without a history of cardiovascular disease (CVD) (17,18).…”

“…The myocardial structure is heterogeneous, with layer-specific fiber orientations ranging from largely circumferential at the mid-wall to more oblique at the endocardium and epicardium (19). Beyond the comparison of LV global and regional strains, some studies have recently emphasized the concept of "layerspecific strain, " defined by the fact that global strains measured in the endocardium, epicardium, or mid-wall using CMR are not equivalent for the identification of systolic dysfunction or cardiovascular outcomes (17).…”