CONSORT 2010 Flow Diagram
KFS
During the study period, 258 patients underwent inpatient examination and preparation for heart surgery in the clinic. Of these patients, 114 patients did not meet the inclusion criteria, 8 refused to participate in the study, and in 2 patients, after the examination, it was decided that surgery was not appropriate. As a result, 134 patients were included in this study and were randomized into two groups: the NMES group (n = 67), in which, along with the standard preoperative rehabilitation program, patients received a course of NMES, and the control group (n = 67), who underwent a standard preoperative rehabilitation program. For various reasons, 13 patients did not complete the prehabilitation course (5 in the NMES group and 7 in the control group), so 122 patients were included in the final analysis: 62 patients in the NMES group and 60 patients in the control group. When comparing the baseline parameters in the groups, there were no differences in clinical and anamnestic data (The initial strength indicators of the studied muscles and 6MWT distance also had no significant differences in the groups (The change in the maximal knee extensor strength (KES) from baseline to the second test after prehabilitation is shown in The maximal knee flexor strength (KFS) increased from baseline to the second test only in the NMES group, not in the control (The handgrip strength during the re-examination slightly increased in the NMES group, and in the control, it decreased slightly, but the differences in the re-test did not reach statistical significance (A similar dynamic was noted for the 6MWT—the distance during the repeated test in the NMES group increased, and in the control, it slightly decreased. This turned out to be sufficient to obtain statistically significant differences between the groups in the repeated test (Other indicators of muscle status are presented in 