Comparison of three-dimensional proximal isovelocity surface area to cardiac magnetic resonance imaging for quantifying mitral regurgitation.

The aim of our study was to evaluate 3-dimensional (3D) color Doppler proximal isovelocity surface area (PISA) as a tool for quantitative assessment of mitral regurgitation (MR) against in vitro and in vivo reference methods. A customized 3D PISA software was validated in vitro against a flowmeter MR phantom. Sixty consecutive patients, with ≥mild MR of any cause, were recruited and the regurgitant volume (RVol) was measured by 2D PISA, 3D peak PISA, and 3D integrated PISA, using transthoracic (TTE) and transesophageal echocardiography (TEE). Cardiac magnetic resonance imaging (CMR) was used as reference method. Flowmeter RVol was associated with 3D integrated PISA as follows: y  = 0.64 x  + 4.7, r 2  = 0.97, p  y  = 0.88 x  + 4.07, r 2  = 0.96, p r 2  = 0.76, y  = 0.95 x  − 3.95, p r 2  = 0.67, y  = 1.00 x  + 6.20, p  r 2  = 0.54, y  = 0.76 x  + 0.18, p