Effects of Transcutaneous Electrical Nerve Stimulation on Myocardial Protection in Patients Undergoing Aortic Valve Replacement: A Randomized Clinical Trial

Background: Transcutaneous electrical nerve stimulation (TENS) has been found to have cardioprotective effects. However, its effects on adult cardiac surgery patients remain unclear. We investigated the effects of TENS on myocardial protection in patients undergoing aortic valve replacement surgery using cardiopulmonary bypass.MethodsThirty patients were randomized to receive TENS or sham in three different anesthetic states – pre-anesthesia, sevoflurane, or propofol (each n = 5). TENS was applied at the upper arm for 30 min. Sham treatment was provided without nerve stimulation. The primary outcome was the difference in myocardial infarct size following ischemia-reperfusion injury in rat hearts perfused with pre- and post-TENS dialysate from the patients using Langendorff perfusion system.ResultsThere were no differences in myocardial infarct size between pre- and post-treatment in any group (41.4 ± 4.3% vs. 36.7 ± 5.3%, 39.8 ± 7.3% vs. 27.8 ± 12.0%, and 41.6 ± 2.2% vs. 37.8 ± 7.6%; p = 0.080, 0.152, and 0.353 in the pre-anesthesia, sevoflurane, and propofol groups, respectively).ConclusionsTENS did not have a cardioprotective effect in patients undergoing aortic valve replacement surgery.Trial registrationThis study was registered at clinicaltrials.gov (NCT03859115, on March 1, 2019).