Doppler echocardiography is an established technique for the routine assessment of prosthetic heart valve function; its accuracy in the estimation of pressure valve gradients has been demonstrated in comparative studies with invasive data.<sup>1Wilkins G.T., Gillam L.D., Kritzer G.L., Levine R.A., Palacios I.F., Weyman A.E. Validation of continuous-wave Doppler echocardiographic measurements of mitral and tricuspid prosthetic valve gradients: a simultaneous Doppler-catheter study Circulation 1986 ;  74 : 786-795 [cross-ref]

Haga clic aquí para ir a la sección de Referencias,2Burstow D.J., Nishimura R.A., Bailey K.R., Reeder G.S., Holmes D.R., Seward J.B., Tajik A.J. Continuous-wave Doppler echocardiographic measurements of prosthetic valve gradients—a simultaneous Doppler-catheter corrdatjve study Circulation 1989 ;  80 : 504-514 [cross-ref]

Haga clic aquí para ir a la sección de Referencias</sup> Ultrasound examination therefore is an important aid in the clinical follow-up of these patients. Nevertheless, the variability of normal values for transprosthetic Doppler gradients is relatively wide, depending basically on the model and size of the valve.<sup>3Goldrath N., Zimes R., Vered Z. Analysis of Doppler-obtained velocity curves in functional evaluation of mechanical prosthetic valves in the mitral and aortic positions J Am Soc Echo 1988 ;  1 : 211-225

Haga clic aquí para ir a la sección de Referencias,4Nihoyannopoulos P., Karnbouroglou D., Athanassopoulos G., Nadazdin A., Smith P., Oakley C.M. Doppler haemodynamic profiles of clinically and echocardiographically normal mitral and aortic valve prostheses Eur Hean J 1992 ;  13 : 348-355

Haga clic aquí para ir a la sección de Referencias</sup> For this reason, the availability of reference values for different valve sizes of a particular model is necessary for a correct assessment of the prosthetic function in every patient. This study reports the normal range of Doppler gradients in a large series of patients with clinically normal-functioning Monostrut Björk-Shiley valves<sup>5Arís A., Padró J.M., Cámara M.L., Lapiedra O., Caralps J.M., Borrás X., Carreras F., Pons-Lladó G. The Monostrut Björk-Shiley valve J Thorac Cardiovasc Surg 1992 ;  103 : 1074-1082

Haga clic aquí para ir a la sección de Referencias</sup> (Shiley, Inc., Irvine, California) in the aortic or mitral position, obtained either postoperatively or over a long-term follow-up.