Abstract 3556: Usefulness of the Proximal Isovelocity Surface Area Method for Quantification of the Severity of Aortic Regurgitation in Patients with Eccentric Regurgitant Jets: Comparison with Cardiac Magnetic Resonance
Background. In pts with aortic regurgitation (AR), Doppler-echocardiographic assessment of the proximal isovelocity surface area (PISA) permits quantification of AR severity. Since this assessment is usually performed on color flow images obtained from apical windows, it may underestimate AR severity in pts with eccentric as opposed to central AR jets.
Aim. The aim of this study was 1- to test if the accuracy of the PISA method performed from the apical window is similar in pts with eccentric vs. central AR jets and 2- to assess if imaging from the parasternal window (instead of the apical window) allows for a more parallel orientation of the ultrasound beam compared to the AR jet and hence for a better quantification of AR severity in pts with eccentric jets.
Methods. 18 pts with eccentric AR were studied and compared to 14 pts with central AR. Regurgitation volumes (RV) were calculated by the PISA method from both apical and parasternal windows and compared to cardiac magnetic resonance (cMR) derived RVs (by phase contrast in the ascending aorta), used as reference.
Results. PISA RV obtained from the apex in pts with eccentric AR underestimated cMR RV by 47±22 mL (p<0.05), whereas those obtained in pts with central AR did not (2±9 mL). In pts with eccentric AR, imaging from the parasternal window completely corrected the bias (-5±12 mL, p=n vs. central jets). In eccentric AR, PISA RV correlated better with cMR RV when obtained from the parasternal (r=0.88) rather than the apical window (r=0.54).
Conclusions. In pts with eccentric AR, quantification of AR severity by the PISA method is feasible but more accurate when color flow images are obtained from the parasternal rather than the apical window.