Endothelial function is calculated as the ratio between the magnitude of the average post-obstructive PWA (1.5–2.5 min after release of the arterial occlusion) and average 5 min of baseline PWA (pre-occlusion baseline period), corrected to systemic changes (observed at the non-obstructed arm). The threshold for a good EndoPAT result is an RHI of 1.67 and above (Fig 1).Fig. 1Correlation between TOA* to RHI