Use of Impedance Cardiography and Applanation Tonometry for Prediction of the Antihypertensive Effect of Two Drugs

Study Overview
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Brief Summary
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The principal aim of the study is to determine whether the hemodynamic parameters measured with the two methods -impedance cardiography and applanation tonometry- can be predictive of the antihypertensive effect of two different classes of drugs, ATII antagonists and diuretics. The drugs that will be used in the study are olmesartan and chlorthalidone and the duration of the study is 12 months. The other basic aim of the study is to determine whether there is a difference (>6mmHg) between the two drugs regarding the reduction of the mean 24hour blood pressure and the effect of them on the hemodynamic parameters. The hemodynamic parameters that will be measured by applanation tonometry are augmentation index, central blood pressure and pulse wave velocity. The hemodynamic parameters that will be measured by impedance cardiography are cardiac index, thoracic fluid content index, systemic vascular resistance index and others.

Detailed Description
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The principal aim of the study is to determine whether the hemodynamic parameters measured with the two methods -impedance cardiography and applanation tonometry- can be predictive of the antihypertensive effect of two different classes of drugs, ATII antagonists and diuretics. The drugs that will be used in the study are olmesartan and chlorthalidone and the duration of the study is 12 months.

Official Title
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Use of Impedance Cardiography and Applanation Tonometry for Prediction of the Antihypertensive Effect. Comparison Between an ATII Receptor Antagonist and a Diuretic.

Conditions
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Arterial Stiffness, Ambulatory Blood Pressure Monitoring

Intervention / Treatment
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* Drug: Olmesartan
* Drug: Chlorthalidone


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age > 18 years Drug naive patients with 1st or 2nd grade Arterial Hypertension according to the ESH/ESC guidelines 2013 The patient has signed the concent form Exclusion Criteria: Secondary Hypertension 3rd grade of Arterial Hypertension Chronic renal failure Diabetes Mellitus Sleep apnea syndrome Chronic or acute inflammatory diseases Stroke, myocardial infarction, angina pectoris in the past 6 months Heart failure Liver disease Neoplasms Pregnancy Valvular Heart disease Heigt < 120cm or > 230cm, Weight <30kg or >155kg Heart Arrhytmias Artificial cardiac pacemaker Hemodymanic unstable patients

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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Olmesartan<br>ARB administration (OLMESARTAN) at a starting dose and titrating at 15 weeks according to reach blood pressure target | Drug: Olmesartan<br>* Administration of olmesartan at starting dose and titrating in order to reach the target blood pressure.<br>* Other names: Olartan;|
| Active Comparator: Chlorthalidone<br>Diuretic administration (chlorthalidone) at a starting dose and titrating at 15 weeks according to reach blood pressure target | Drug: Chlorthalidone<br>* Administration of chlorthalidone at starting dose and titrating in order to reach the target blood pressure.<br>* Other names: Hygroton;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pulse wave velocity | Measured by Sphygmocor devive | 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Systemic vascular resistance | Measured by impendance cardiography | 12 months | 
| Ambulatory blood pressure | Daytime and nighttime systolic and diastolic blood pressure | 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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olmesartan, chlorthalidone, hemodynamics