Effects of QSKL on the cardiac structures detected by HE staining. When observed under the magnification of 200x, (a) shows that the myocardial cells of the sham operation group were arranged in an orderly way. In contrast, (b) shows that the cells of model group lost their normal structures. Cardiac fibers were dissolved and necrotized, with infiltration of many inflammatory cells. (c) and (d) show that cells were arranged in a much orderly way and there were fewer inflammatory infiltrations in the QSKL and positive control group.