P814Superiority of validated echocardiographic regurgitant fraction for the grading of aortic regurgitation.


    loading  Checking for direct PDF access through Ovid

Abstract

Purpose: Echocardiographic quantification of aortic regurgitation (AR) is a mainstay for diagnosis and indication for aortic valve surgery in severe AR. To this end, Doppler regurgitant volume fraction (ARF) is considered a gold standard. Because ARF is cumbersome to calculate, qualitative and semi-quantitative indices are used: eye-balling of color Doppler AR jet (CD); AR jet width/outflow tract diameter ratio (JLVOT); AR velocity pressure half time (PHT); time-velocity integrals of diastolic reverse flow in the thoracic descending (Ad, cm) and abdominal (Aa, cm) aorta. We also re-evaluated feasibility and accuracy of Ad and Aa, compared to validated ARF, to detect and grade AR in an unselected population, because published experience is scarce and limited to severe AR.Methods: We measured Ad and Aa in 90 patients with AR and no mitral regurgitation, 80 patients with different heart diseases (HD) and in 20 normal subjects (N). Reference grading of AR into mild, moderate or severe was achieved with ARF, by measuring pulsed Doppler mitral annular inflow and left ventricular (LV) outflow, previously validated in 30 separate patients with cardiac magnetic resonance imaging. In all patients (sinus rhythm) we measured LV volumes, mass index, ejection fraction and filling pressures (E/e'), and pulmonary systolic pressure (PSP).Results: Age, BSA, heart rate and sex were comparable in N, HD and AR. Heart rate, LV volumes, ejection fraction, E/e', and PSP were comparable between patients with severe and non severe AR. In AR, jet direction was central in 45%, posterior in 51% and anterior in 4%, and in severe AR the jet was posterior in 70%. JLVOT and PHT were not feasible in respectively 30% and 60% of severe AR. Feasibility, sensitivity and specificity of Ad and Ao in detecting any degree of AR were respectively 96%, 97%, 5%, and 20%, 31%, 95%. To the end of detecting severe AR, Ad using a 12 cm cutoff showed a 100% sensitivity, but also a 47% false positive rate, whereas Aa was of no utility. Qualitative evaluation with CD caused misclassification of 10% and 30% of severe AR as respectively mild and moderate, whereas 58% of mild or moderate AR was classified as severe.Conclusions: In our adult population, Doppler aortic backflow, either thoracic or abdominal, was not an accurate surrogate for validated ARF. Qualitative evaluation of AR, which is used frequently, was greatly misleading in the selection of patients with severe AR for aortic valve surgery. All patients with AR considered for valve surgery should undergo a quantitative Doppler evaluation after adequate learning curve and validation.

    loading  Loading Related Articles