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