The value of the peak systolic velocity ratio in the assessment of the haemodynamic significance of subcritical iliac artery stenoses

Objectives: iliac stenoses with a PSV ratio between 2.0 and 3.0 in patients with symptomatic arterial obstructive disease of the legs might be misinte rpreted when compared with intra-arterial pressure measurements (IAPM). The aim of this study was to compare the value of the PSV ratio with IAPM as t he reference standard in the assessment of the haemodynamic significance of subcritical iliac artery stenoses (iliac stenosis with PSV ratio between 1 .5 and 3.5). Design, patients and methods: fifty-eight iliac tracts in 53 consecutive pa tients with symptomatic arterial obstructive disease of the legs with an is olated stenosis with PSV ratio between 1.5 and 3.5 were studied prospective ly. The results of those iliac duplex scanning were compared to IAPM. Results: a poor agreement was found between IAPM and PSV ratios. For the PS V ratios greater than or equal to2.0, 2.5 and 3.0 the sensitivities were 74 %, 37% and 16%, respectively. The specificities were 70%, 90% and 95%, the positive predictive values 82%, 88% and 86%, respectively, and the negative predictive values 58%, 43% and 37%, respectively. Conclusion: the results of this study show that the PSV ratio parameter is not accurate enough to evaluate the haemodynamic significance of subcritica l iliac artery stenoses.