Page 44 - The role of advanced echocardiography in patients with ischemic heart disease - Rachid Abou

Chapter two. Level and Layer Specific Left Ventricular Longitudinal Strain
Table 4. Level specific peak systolic left ventricular longitudinal strain divided by age categories
Age categories (years)
Myocardial level
<45 (n=86)
45-54 (n=82)
55-64 (n=83)
65-74 (n=80)
>75 (n=77)
Overall (n=408)
Basal Mid Apical *p-value
-17.1 ± 2.3 -18.8 ± 2.0 -21.6 ± 3.3 <0.001
-16.9 ± 2.1 -19.1 ± 2.4 -22.2 ± 3.6 <0.001
-16.7 ± 2.3 -19.0 ± 1.8 -22.9 ± 3.4 <0.001
-16.8 ± 2.0 -18.9 ± 1.9 -23.4 ± 4.3 <0.001
-16.1 ± 2.1 -18.4 ± 2.1 -23.1 ± 4.0 <0.001
-16.7 ± 2.2 -18.8 ± 2.0 -22.6 ± 3.8 <0.001
Data are presented as mean ± standard deviation. *p-value for level specific outcome (referenced to apical)
Layer-specific analysis (endocardium, mid-myocardium and epicardium) showed a decrease in magnitude of longitudinal strain from endo- to mid- and epicardium for the overall population and all individual age categories (p<0.001 for all groups; Table 5). This trend did not differ across the various age categories (endocardium, p=0.371; mid, p=0.140; epicardium, p=0.493).
Table 5. Layer specific global peak systolic left ventricular longitudinal strain divided by age categories
Age categories (years)
Myocardial layer
<45 (n=86)
45-54 (n=82)
55-64 (n=83)
65-74 (n=80)
>75 (n=77)
Overall (n=408)
Endocardium Mid-myocardium Epicardium *p-value
-21.9 ± 2.3 -18.1 ± 2.0 -16.4 ± 1.8 <0.001
-22.1 ± 2.5 -19.1 ± 2.2 -16.8 ± 2.3 <0.001
-22.2 ± 2.1 -19.3 ± 1.7 -16.8 ± 1.7 <0.001
-22.5 ± 2.5 -19.5 ± 2.1 -16.8 ± 1.7 <0.001
-22.1 ± 2.4 -18.8 ± 2.2 -16.6 ± 1.9 <0.001
-22.1 ± 2.4 -19.1 ± 2.1 -16.7 ± 1.9 <0.001
Data are presented as mean ± standard deviation.
*p-value for layer specific outcome (referenced to epicardium)
On univariate analysis increasing age was not associated with peak systolic strain at the endocardial (β=-0.028, p=0.572), mid-myocardial layer (β=-0.046, p=0.357) or the epicardial layer (β=-0.063, p=0.206). In addition, hypercholesterolemia, smoking, heart rate, calcium channel blockers and LV mass (indexed) were not associated with longitudinal strain at all layers. Therefore, these variables were not forced into the multivariate analysis. On multivariable analysis, diabetes mellitus was associated with more impaired longitudinal strain in the endocardium (β=0.103, p=0.040). Whereas, male gender was associated with more impaired longitudinal strain at the epicardium (β=-0.116, p=0.018) (Table 6). The effect of age on layer specific peak systolic strain, corrected for these variables (gender, diabetes mellitus) is demonstrated in Figure 4. There were no significant differences in global peak systolic strain across the age
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