Limitations in the Applicability of the Simplified Bernoulli Relation to Aortic Stenosis

Abstract

tance of 2.5 cm downstream of the valves. Their data, when interpreted in terms of K, show that K has values between 2 and 2.5 for St. Jude (St.

Effective Valve Opening Area in the Detection of Dysfunctional Aortic Valve Prostheses: A Differentiated Statistical Analysis of This Parameter Including the Introduction of Minimal Expected Normal Values as Borderline to Dysfunctional Stenotic Prostheses

“…Gradients, velocities, velocity integrals, etc. should not be used as parameters of first choice for the evaluation of VP function because of their close dependency on SV 8,13,20,21,23,24 . However, gradients are useful for estimating left ventricular SV and for analyzing measured parameters for plausibility.…”

“…Using the data of the “receiver operating characteristics” (ROC), 20,21 specificity and sensitivity of the introduced formula were calculated for each prosthetic size. Normally functioning prostheses were defined as true positives, dysfunctional AVPs as true negatives.…”

“…should not be used as parameters of first choice for the evaluation of VP function because of their close dependency on SV. 8,13,20,21,23,24 However, gradients are useful for estimating left ventricular SV and for analyzing measured parameters for plausibility. One consequence is that a prosthetic valve mismatch 25,26 can easily be identified in normal SV by unusual high transprosthetic gradients but normal VA.…”