Mechanisms and Treatment of Intradialytic Hypertension

Study Overview
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Brief Summary
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To determine in a cross sectional case-controlled cohort study of 50 hemodialysis patients if blood pressure elevations with hemodialysis are associated with decreased endothelial cell function (measured by brachial artery flow mediated dilation and endothelial progenitor cell number), both of which are novel mechanistic markers in the causal pathway for detrimental cardiovascular outcomes; and To determine if lowering blood pressure with carvedilol in 25 ESRD subjects with blood pressure elevations with hemodialysis can improve endothelial cell dysfunction as a surrogate mechanistic marker for improving cardiovascular outcomes.

Official Title
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Blood Pressure, Endothelial Cell Dysfunction, and Outcomes in Dialysis Patients

Conditions
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Intradialytic Hypertension

Intervention / Treatment
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* Drug: Carvedilol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: on hemodialysis > 30 days aged 18 to 80 years old ability to provide informed consent Primary nephrologist deems patient is at target dry weight Predialysis SBP >140 or postdialysis SBP>130 Exclusion Criteria: Patients with active wounds Blood pressure unable to be measured by routine mechanisms in the upper extremity Change in blood pressure medications in the previous 2 weeks Intolerance of beta or alpha-blockers pregnancy Resting heart rate <50 Life expectancy < 6 months Current therapy with carvedilol or contraindication to carvedilol (ONLY in the intervention arm)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control<br>Patients without intradialytic hypertension defined as average pre to post hemodialysis SBP falling >10 mmhg for more than 4/6 of the last dialysis treatment sessions | |
| Active Comparator: Intervention<br>Patients with intradialytic hypertension defined as average pre to post hemodialysis SBP elevation of >10 mmhg for more than 4/6 of the last dialysis treatment sessions | Drug: Carvedilol<br>* Carvedilol 6.25 mg BID titrated weekly to maximum of 50 mg bid<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Endothelial Progenitor Cells | ALDH bright cells reported as percentage of mononuclear cells. These were assayed using flow cytometry CD34/CD133 endothelial progenitor cells reported as percentage of mononuclear cells. These were assayed using flow cytometry | 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Flow Mediated Vasodilation | Measured as percent change in brachial artery diameter from baseline to post shear stress for an individual measurement. Follow up measurements were obtained in intervention subjects 12 weeks later | 12 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hypertension, Hemodialysis