Figure 1
From: Defining a therapeutic range for regeneration of ischemic myocardium via shock waves
Shock wave therapy induces necrosis only at very high energy levels. (a) To evaluate at which energy levels SWT would induce cellular damage, we performed an LDH assay upon therapy. SWT caused no necrosis induced until energy levels of 0.27 mJ/mm2 total flux density in T25 flasks. Means ± SEM. *p < 0.05, ****p < 0.0001. n = 3. (b) Scheme for the mechanical setup of SWT in vitro: To evaluate whether the occurrence of necrosis might depend on the size and form of the cell culture flask in which the cells undergo SWT, HUVECs were seeded in 6, 12, 24 and 96 well plates and subjected to SWT. (c) In microwell plates with a surface smaller than 9,5cm2 (12, 24 and 96 well plates) necrosis could be measured at a level as low as 0.15 mJ/mm. This might be attributed to phenomena of constructive interference. Means ± SEM. **p < 0.01; ***p < 0.001, ****p < 0.0001. n = 3–4. (d) Comparable levels of necrosis could be discovered in fibroblasts and cardiomyocytes upon shockwave therapy. (e) Within the targeted tissue, shock waves induce alternating positive and negative pressure due to their specific wave profile. Positive and negative pressure induced by SWs were measured by a hydrophone showing an increase of pressure upon release of the wave with subsequent decrease to negative pressures. (f) Positive pressure increases concomitant with the total energy flux density and thus necrosis. (g) Initially, negative pressure increases concomitant with the total flux density until plateauing at a level of 3,8 MPa. Statistical comparisons between multiple groups: one-way ANOVA with Tukey post hoc analysis.
