Effects of TENS on Myocardial Protection in Patients Undergoing AVR

Study Overview
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Brief Summary
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Patients undergoing aortic valve replacement are randomized to receive TENS (transcutaneous electrical nerve stimulation) or sham stimulation at one arm for 30 min under various anesthetic conditions: no anesthesia (preanesthesia), sevoflurane or propofol anesthesia. Cardioprotective effects of TENS are compared through Langendorff rat heart perfusion system using plasma dialysate from patients.

Detailed Description
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Patients undergoing aortic valve replacement are randomized to one of six groups: preanesthesia-TENS (transcutaneous electrical nerve stimulation), preanesthesia-sham, sevoflurane-TENS, sevoflurane-sham, propofol-TENS, propofol-sham. Patients receive TENS or sham stimulation (without electrical pulse generation) at one arm for 30 min under no anesthesia (preanesthesia) or sevoflurane or propofol anesthesia. In all patients, blood samples are obtained before and after TENS or sham procedure to make plasma dialysate to perfuse rat hearts subjected to ischemia-reperfusion injury through Langendorff system. Cardioprotective effects are determined by comparing infarct sizes of rat hearts perfused with human plasma dialysate, which reflects cardioprotective effects of TENS in human subjects. By comparing infarct size differences, the myocardial protective effects of TENS in various anesthetic conditions can be determined in human subjects undergoing aortic valve replacement.

Official Title
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Effects of TENS on Myocardial Protection in Patients Undergoing AVR

Conditions
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Myocardial Protection

Intervention / Treatment
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* Procedure: TENS (transcutaneous electrical nerve stimulation)
* Procedure: sham intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients undergoing aortic valve replacement Exclusion Criteria: co-medications: metformin, nitroglycerine, nicorandil discomfort at TENS or loss of intact skin uncontrolled hypertension or diabetes mellitus severely impaired renal or hepatic function peripheral vasculopathy or neuropathy did not consent to participate pregnancy

Ages Eligible for Study
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Minimum Age: 20 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: preanesthesia-TENS<br>Patients in preanesthesia-TENS group receive TENS for 30 minutes at one arm before anesthesia. | Procedure: TENS (transcutaneous electrical nerve stimulation)<br>* transcutaneous nerve stimulation with electrical pulse generation<br>|
| Sham Comparator: preanesthesia-sham<br>Patients in preanesthesia-sham group receive sham stimulation for 30 minutes at one arm before anesthesia. | Procedure: sham intervention<br>* sham stimulation without electrical pulse generation<br>|
| Experimental: sevoflurane-TENS<br>Patients in sevoflurane-TENS group receive TENS for 30 minutes at one arm under sevoflurane anesthesia. | Procedure: TENS (transcutaneous electrical nerve stimulation)<br>* transcutaneous nerve stimulation with electrical pulse generation<br>|
| Active Comparator: sevoflurane-sham<br>Patients in sevoflurane-sham group receive sham stimulation for 30 minutes at one arm under sevoflurane anesthesia. | Procedure: sham intervention<br>* sham stimulation without electrical pulse generation<br>|
| Experimental: propofol-TENS<br>Patients in propofol-TENS group receive TENS for 30 minutes at one arm under propofol anesthesia. | Procedure: TENS (transcutaneous electrical nerve stimulation)<br>* transcutaneous nerve stimulation with electrical pulse generation<br>|
| Active Comparator: propofol-sham<br>Patients in propofol-sham group receive sham stimulation for 30 minutes at one arm under propofol anesthesia. | Procedure: sham intervention<br>* sham stimulation without electrical pulse generation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Infarct size after TENS | Infarct size of rat hearts perfused with dialysate after TENS compared with sham | 30 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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transcutaneous electrical nerve stimulation, sevoflurane, propofol, anesthesia, myocardial protection