Bioimpedance Evaluation of Therapeutic Titration in Essential, Refractory Hypertension

Study Overview
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Brief Summary
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To determine whether impedance cardiography (ICG) parameters can predict favorable or unfavorable blood pressure (BP) response and time to BP control prior to initiation or intensification of specific antihypertensive drug classes and drug combinations, independent of initial BP levels.

Detailed Description
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Patients with higher vascular resistance index and/or lower arterial compliance index will lower BP faster and to a greater degree overall when receiving vasodilating agents - such as ACEI's, ARB's, dihydropyridine CCB's, direct vasodilators, and central alpha agonists. Patients with an elevated cardiac index will lower BP faster and to a greater degree overall when receiving agents that reduce contractility, heart rate, or blood volume - such as beta blockers, non-dihydropyridine CCB's, and other agents that are known to reduce cardiac index. Patients with an elevated thoracic fluid content or lower orthostatic change in thoracic fluid content will lower BP faster and to a greater degree overall when receiving diuretics (thiazide, loop, potassium sparing), however - one of these agents will emerge as a superior alternative to reduce BP in patients with high thoracic fluid content / low orthostatic change in thoracic fluid content.

Official Title
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Bioimpedance Evaluation of Therapeutic Titration in Essential, Refractory Hypertension (BETTER-HTN)

Conditions
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Hypertension

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: > 18 years of age Able to provide written consent Meet JNC definition of hypertension Lab results with 6 months for: serum creatinine, urine albumin/creatinine ratio, and at least one of the following: serum glucose, or glycated hemoglobin, or hemoglobin A1C Exclusion Criteria: Active cardiovascular disease (unstable angina, stage C or D heart failure, uncontrolled superventricular arrhythmia, hx of ventricular arrhythmia, stroke or TIA within 6 months, ACS within 6 months) Implantation of activated ventricular pacemaker Known hypersensitivity or allergy to sensor gel or adhesives Skin lesions prohibiting sensor placement

Ages Eligible for Study
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Minimum Age: 18 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| ICG<br>Group will have results blinded during observational phase of study. Results will be revealed at time of testing during the validation phase of the study. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To determine if ICG can predict therapeutic response to antihypertensive medications |  | 2009-2010 | 
| To confirm derivation phase of ICG prediction to therapeutic response of antihypertensive medications. |  | 2010-2011 | 

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