Velocity Vector Imaging in Patients With Moderate-to-Severe Aortic Regurgitation

Study Overview
=================
Brief Summary
-----------------
Velocity Vector Imaging may provide reliable and detailed information on left ventricular segmental function in asymptomatic patients with moderate-to severe AR. This may help to identify subclinical myocardial dysfunction in order to operate early enough to prevent postoperative heart failure and restrict unnecessary early operation which could be associated with operative risks and mortality related to prosthetic valves.

Detailed Description
-----------------
Chronic aortic regurgitation (AR) is a progressive process which causes both left ventricular volume and pressure overload. While the volume overload is associated with the degree of the aortic regurgitant volume, the pressure overload occurs as a result of systemic hypertension developed due to increased stroke volume. In early stages, excentric hypertrophy occurs aiming to compensate the volume overload in the left ventricle. Therefore , ejection fraction remains in normal range despite the increasing volume overload. Left ventricular dilatation and impairment in ejection fraction only occur in the end stages of the disease. Asymptomatic patients with chronic aortic regurgitation (AR) have a good prognosis in the presence of preserved systolic function. Therefore it is a challenge to identify patients with subclinical left ventricular (LV) dysfunction. Velocity vector imaging (VVI) is a new echocardiographic method based on two dimensional gray scale imaging, which is angle independent and can provide more accurate data about cardiac function.

Official Title
-----------------
Velocity Vector Imaging in Patients With Moderate-to-Severe Aortic Regurgitation

Conditions
-----------------
Aortic Regurgitation

Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Moderate-to-severe aortic regurgitation identified by Standard echocardiography. Chronic isolated aortic regurgitation Being asymptomatic ( Class 1 according to NYHA) Sinusal rhythm Exclusion Criteria: Ejection fraction < 50% Mitral valve disease accompanied to aortic regurgitation (patients with over mild degree of mitral regurgitation and stenosis Aortic stenosis Previous myocardial infarction, or the patients with >50% coronary occlusion in any of the coronary arteries. Cardiomyopathies AV conduction disorders Chronic renal or hepatic insufficiency Malignities

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| A<br>Patients with moderate-to-severe aortic regurgitation having normal left ventricular ejection fraction | |
| B<br>Age, sex and bodymass index matched healthy subjects | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Velocity Vector Imaging derived segmental systolic peak Strain and Strain rates |  | April 2008 | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Aortic regurgitation,velocity vector imaging