Atrioventricular Valve Regurgitation Vena Contracta; Echo Versus MRI
Atrioventricular Valve Regurgitation Vena Contracta; Echo Versus MRI
The purpose of this pilot study is to evaluate mitral (left atrioventricular valve) and
 tricuspid (right atrioventricular valve (AVV)) regurgitation using cardiac magnetic resonance
 imaging (CMR) as the non-invasive "gold standard" compared to transthoracic echocardiography
 (TTE) to evaluate measurements of the width of the regurgitation jet (vena contracta (VC)) to
 demonstrate the utility of the VC as a means to objectively evaluate atrioventricular valve
 regurgitation. In addition, feasibility and other quantitative and qualitative measures of
 regurgitation will be compared between CMR and TTE.

 -  Hypothesis 1: The ability to objectively evaluate atrioventricular valve regurgitation
 and VC width with TTE and CMR has a high feasibility rate with acceptable intra and
 inter-observer variability by two independent readers.

 -  Hypothesis 2: There will be positive correlation between the TTE measurement of the VC
 width and quantitative assessment of atrioventricular valve regurgitation by TTE and
 CMR.

 -  Hypothesis 3: There will be a positive correlation between the quantitative measurements
 of atrioventricular valve regurgitation by phase contrast velocity encoded CMR with
 quantitative values as measured by TTE.

 -  Hypothesis 4: There will be a positive correlation between qualitative assessment of
 atrioventricular valve regurgitation by CMR compared to TTE.
BACKGROUND, SIGNIFICANCE, AND RATIONALE (including preliminary studies and any results) The
 integrity of the two atrioventricular valves (AVV)(i.e., the mitral and tricuspid valve)
 plays an important role in the evaluation and management of patients with congenital and
 acquired heart disease. Loss of valve integrity (i.e., valve leakage in the reverse direction
 of normal blood flow), is known as valve regurgitation. Increasing severity of mitral
 regurgitation has been associated with increased mortality and morbidity. Tricuspid
 regurgitation can be a progressive problem that results in right atrial and ventricular
 dilation and possible right heart failure. Similarly, mitral valve regurgitation can result
 in left atrial and left ventricular enlargement. Treatment options for valvular regurgitation
 are based upon the degree of regurgitation in both adults and children. Therefore, assessment
 of the degree of AV valvular regurgitation has important clinical ramifications. AV valve
 regurgitation can be assessed in several ways, including both invasive and noninvasive
 modalities. The invasive assessment is performed by cardiac catheterization which enables
 qualitative and quantitative measurements of AV valve regurgitation and in the past has been
 considered the "gold standard". Noninvasive assessment is still the preferred method and
 consists of echocardiography, electrocardiography, chest x-ray, and CMR. TTE can be used
 qualitatively to describe the amount of AV valve regurgitation by the degree of color flow
 Doppler reflux into the left atrium during left ventricular contraction. This approach grades
 the regurgitation as mild, moderate or severe similar to angiographic grading systems, but is
 relatively subjective and affected by technical factors. TTE can quantitatively evaluate AV
 valve regurgitation through calculation of regurgitation orifice area, regurgitation volume
 and regurgitation fraction. These methods have been shown to have a good correlation when
 used for mitral valves compared to cardiac catheterization and CMR in adults. However,
 quantitative techniques are time consuming and require multiple measurements and more complex
 calculations. A simpler technique of objectively characterizing the regurgitation of the AV
 valves by TTE is measuring the width of the vena contracta (VC). The VC is the narrowest
 portion of a regurgitant jet which occurs at the level of or just below the valve leaflets
 and represents the effective regurgitant orifice. In adult studies, this method has shown
 that increase in VC width of the mitral valve strongly correlates with qualitative
 angiographic grades and quantitative measurements of regurgitant volume by cardiac
 catheterization and is a better assessment of regurgitation than measuring the regurgitant
 jet by TTE. Changes in VC width also had strong correlation with quantitative measurements of
 regurgitant volume and regurgitant orifice area using TTE. It is our intent to evaluate the
 feasibility and correlation of measurements of AV valve regurgitation by TTE with focus on
 the VC in pediatric patients compared to the non-invasive "gold standard" measurements by
 CMR.
Inclusion Criteria:

 -  Audible AV valve regurgitation on clinical exam, as noted by most recent clinic note.

 -  Clinically indicated CMR study scheduled and have had an echocardiogram in the last 6
 months

 Exclusion Criteria:

 -  Poor quality CMR study

 -  Unable to complete a CMR

 -  Have a contraindication to CMR scan (e.g., pregnancy, pacemaker or defibrillator
 presence, unable to hold still within scanner for imaging)

 -  Common AV valve

 -  Corresponding semilunar valve regurgitation which precludes use of stroke volume
 comparison as a second means of assessing AVV regurgitation by CMR

 -  Intracardiac shunts which precludes use of stroke volume comparison as a second means
 of assessing AVV regurgitation by CMR.