Postprocedural Peak Systolic Blood Flow Measurements Correlate with the Need for Stent Reintervention at 12 Months

Abstract

Purpose Duplex surveillance of arterial stents has focused on detecting in-stent restenosis. Although velocity is commonly reported, that differs from blood flow, and patency of arterial prostheses is flow-dependent. Preliminary evaluation was performed to determine if postprocedure peak systolic blood flow (PSF) through stents correlates with rate of repeat intervention at 12 months. Materials and Methods Retrospective review of consecutive patients undergoing arterial stent placement was performed. Demographics, comorbidities, stent size, postprocedure duplex information, and repeat intervention rates were recorded. PSF was calculated by using peak systolic velocity (PSV) and stent dimensions. Results Consecutive stents ( N = 35) were placed in 27 patients (mean age, 72.6 y ± 14). Twenty stents were free from repeat intervention (FR) and 15 required repeat intervention (RR) at 12 months. There was a significant difference between FR and RR groups with respect to initial in-stent PSV and PSF (92.5 cm/s for FR vs 43.7 cm/s for RR [ P < .002]; 1,918 mL/min for FR vs 722 mL/min for RR [ P < .0001]). PSF showed sensitivity, specificity, and accuracy rates of 92%, 82%, and 86.2%, respectively, for predicting repeat intervention, versus 83%, 71%, and 76% for PSV. Receiver operating characteristic curve analysis showed a greater area under the curve for PSF versus PSV (0.965 vs 0.859). Conclusions PSF from an initial postprocedure duplex study accurately correlates with need for repeat stent intervention at 12 months. PSV had a lower sensitivity, specificity, and accuracy. This preliminary finding must be confirmed by prospective studies in individual vascular beds and larger patient populations. A new approach to stent surveillance is suggested.