Table 4.
End-systolic fiber strains at the anterolateral left ventricle during atrial and local biventricular activation in failing and nonfailing hearts
| Failing Hearts (n = 6) |
Nonfailing Hearts (n = 5) |
|||||
|---|---|---|---|---|---|---|
| Strain/Depth | ATRIAL | ENDO | EPI | ATRIAL | ENDO | EPI |
| Eff | ||||||
| Sub-epi | −0.05 ± 0.02 | −0.04 ± 0.01 | −0.01 ± 0.02 | −0.09 ± 0.02 | −0.06 ± 0.02 | −0.07 ± 0.02 |
| Midwall | −0.10 ± 0.02§ | −0.07 ± 0.02* | 0.01 ± 0.03‡ | −0.17 ± 0.02 | −0.16 ± 0.01* | −0.11 ± 0.02‡ |
| Sub-endo | −0.14 ± 0.02§ | −0.07 ± 0.03† | −0.07 ± 0.03‡ | −0.19 ± 0.02 | −0.18 ± 0.01 | −0.16 ± 0.02 |
| Ecc | ||||||
| Sub-epi | −0.06 ± 0.01 | −0.05 ± 0.02 | −0.03 ± 0.02 | −0.05 ± 0.01 | −0.01 ± 0.03 | −0.003 ± 0.03 |
| Midwall | −0.08 ± 0.02 | −0.07 ± 0.02 | −0.05 ± 0.03 | −0.08 ± 0.03 | −0.06 ± 0.06 | −0.04 ± 0.07 |
| Sub-endo | −0.08 ± 0.01§ | −0.08 ± 0.02* | 0.003 ± 0.03‡ | −0.20 ± 0.04 | −0.16 ± 0.07* | −0.07 ± 0.06‡ |
| Err | ||||||
| Sub-epi | 0.14 ± 0.03 | 0.07 ± 0.02 | 0.05 ± 0.02‡ | 0.15 ± 0.03 | 0.17 ± 0.06 | 0.16 ± 0.04 |
| Midwall | 0.27 ± 0.04 | 0.14 ± 0.03*† | 0.08 ± 0.04‡ | 0.37 ± 0.05 | 0.35 ± 0.06* | 0.29 ± 0.04 |
| Sub-endo | 0.42 ± 0.06§ | 0.20 ± 0.07*† | 0.14 ± 0.06‡ | 0.62 ± 0.08 | 0.55 ± 0.09* | 0.41 ± 0.07‡ |
| Efc | ||||||
| Sub-epi | −0.004 ± 0.02 | 0.01 ± 0.02 | 0.02 ± 0.02 | −0.02 ± 0.01 | −0.05 ± 0.02* | −0.006 ± 0.03 |
| Midwall | 0.01 ± 0.02 | −0.001 ± 0.01 | −0.011 ± 0.01 | 0.02 ± 0.01 | 0.004 ± 0.02 | 0.01 ± 0.01 |
| Sub-endo | 0.001 ± 0.01§ | 0.04 ± 0.05* | −0.03 ± 0.02‡ | 0.06 ± 0.02 | 0.08 ± 0.03 | 0.07 ± 0.03 |
| Ecr | ||||||
| Sub-epi | 0.02 ± 0.02 | 0.02 ± 0.02 | −0.02 ± 0.02 | 0.02 ± 0.01 | −0.05 ± 0.02 | −0.03 ± 0.05 |
| Midwall | −0.02 ± 0.03 | −0.05 ± 0.02 | −0.05 ± 0.01 | 0.03 ± 0.02 | −0.07 ± 0.09 | −0.07 ± 0.08 |
| Sub-endo | −0.07 ± 0.06 | −0.07 ± 0.06 | −0.08 ± 0.04 | 0.001 ± 0.04 | −0.01 ± 0.09* | −0.07 ± 0.09 |
| Efr | ||||||
| Sub-epi | 0.05 ± 0.02 | 0.03 ± 0.02 | 0.02 ± 0.02 | 0.03 ± 0.01 | 0.07 ± 0.03* | 0.05 ± 0.02 |
| Midwall | 0.07 ± 0.04 | 0.04 ± 0.05 | 0.02 ± 0.03 | 0.07 ± 0.03 | 0.04 ± 0.04 | 0.03 ± 0.04 |
| Sub-endo | 0.07 ± 0.03 | 0.001 ± 0.08 | −0.02 ± 0.02‡ | 0.09 ± 0.05 | −0.004 ± 0.09*† | −0.04 ± 0.08‡ |
Values are means ± SE for failing (n = 6) and nonfailing (n = 5) hearts. ATRIAL, left atrial pacing; ENDO, biventricular pacing at local endocardial anterolateral surface; EPI, biventricular pacing at local epicardial anterolateral surface; Sub-epi, subepicardial wall depth (i.e., 25%); Sub-endo, subendocardial wall depth (i.e., 75%); Eff, fiber normal strain; Ecc, cross-fiber normal strain; Err, radial normal strain; Efc, fiber-cross-fiber shear strain; Ecr, cross-fiber-radial shear strain; Efr, fiber-radial shear strain.
P < 0.05, ENDO vs. EPI;
P < 0.05, ENDO vs. ATRIAL;
P < 0.05, EPI vs. ATRIAL;
P < 0.05, failing ATRIAL vs. nonfailing ATRIAL (comparisons performed with a two-way repeated-measures ANOVA and Tukey's post hoc tests).