Use of arterial transfer functions for the derivation of central aortic waveform characteristics in subjects with type 2 diabetes and cardiovascular disease.

In a recent editorial, Mather and Lewanczuk (1) describe the potential value of a generalized transfer function to synthesize the ascending aortic pressure wave from the radial pressure waveform, as recorded indirectly by applanation tonometry. The Food and Drug Administration (FDA) had previously accepted validity under different conditions of a generalized transfer function used in a commercial device: “The SphygmoCor SCOR-Px can calculate the calibrated ascending aortic pressure waveform using the radial artery pressure waveform recorded noninvasively from a radial artery tonometer and a brachial cuff measurement” (2). On the basis of an accompanying article by Hope et al. (3) in Diabetes Care , editorialists expressed concern regarding whether such an approach was applicable in diabetic subjects. There are serious flaws in the report of Hope et al. (3) Their transfer function is …