Pulse waveform analysis in the optic nerve head circulation reflects systemic vascular resistance obtained via a Swan-Ganz catheter.

Abstract

To determine whether a pulse waveform analysis in the optic nerve head (ONH) circulation as determined by laser speckle flowgraphy (LSFG) can provide systemic hemodynamic values - the systemic vascular resistance (SVR) in particular - similar to those obtained by using a Swan-Ganz catheter, which is an invasive method. Sixteen consecutive subjects were examined. Hemodynamic monitoring was obtained from right heart catheterization with a Swan-Ganz catheter and coronary angiography without an intracoronary nitroglycerin administration. Direct blood pressure was measured with a trans-radial approach. Single regression analyses were used to determine the relationship between the blowout score and blowout time, which are the items of the pulse waveform analysis in the ONH, by using LSFG and the hemodynamic parameters. The blowout time was significantly and negatively correlated with the SVR (r = -0.52, p = 0.04), the ocular perfusion pressure with the mean arterial blood pressure of the radial artery (r = -0.52, p = 0.04) and the radial artery pulse pressure (r = -0.52, p = 0.04).The pulmonary capillary wedge pressure (r = -0.44, p = 0.09) and the mean arterial blood pressure of the radial artery (r = -0.44, p = 0.09) tended to be correlated with the blowout time, but did not reach significance. The blowout score was significantly and negatively correlated with the radial artery blood pressure (r = -0.51, p = 0.046). A pulse waveform analysis in the ONH by LSFG may be one of the useful methods for understanding the SVR.