Regressive cross-correlation of pressure signals in the region of stenosis: Insights from particle image velocimetry experimentation

The transform between the input-output pressure signals allowed detection of the region immediately downstream of the stenosis. In particular, if the cross correlative parameter that relates the instantaneous transfer across the input-output signals was greater than the delayed transfer parameter a stenosis is present. In contrast, the delayed transfer parameter was larger for the region upstream of the stenosis. This outcome is particularly valuable as it does not require calibration of the absolute pressure, which can be difficult to determine physiologically due to factors such as arterial geometry and intrathoracic pressure. However, the outcomes need to be validated in more geometries prior to clinical validation.