Duplex ultrasound criteria for in-stent restenosis of mesenteric arteries

Objective: Duplex ultrasound (DUS) criteria are well defined for evaluating high-grade stenosis (>= 70%) of the native superior mesenteric artery (SMA) and celiac artery (CA). It has been shown that native vessel criteria overestimate the degree of in-stent restenosis (ISR) and that velocity criteria for SMA and CA ISR are not well established. The objective of this study was to define DUS velocity criteria for high-grade ISR of the SMA and CA. Methods: A retrospective review of all patients who underwent SMA or CA stenting from a single institution was performed from 2004 to 2013. Patients were excluded if they did not have a DUS examination <4 months before angiography to assess stent patency or adequate angiographic visualization of the ISR. Results: There were 103 paired DUS scans and angiograms analyzed: 66 SMA studies and 37 CA studies. The average peak systolic velocity (PSV) for SMAs was 367 cm/s with <70% ISR and 536 cm/s with >= 70% ISR. The average PSV for CAs was 302 cm/s with <70% ISR and 434 cm/s with >= 70% ISR. For an ISR >= 70% in the SMA, a PSV >= 445 cm/s produced the highest sensitivity (83%) and specificity (83%), with a positive predictive value of 81% and a negative predictive value of 86%. For an ISR >= 70% in the CA, a PSV >= 289 cm/s produced the highest sensitivity (100%) and specificity (57%), with a positive predictive value of 79% and negative predictive value of 100%. Conclusions: Increasing PSV correlates with an increasing degree of ISR for both the SMA and CA. Stented vessels have increased PSV, and therefore native PSV criteria are unreliable for the determination of ISR. The PSV criteria for >= 70% stenosis are higher for ISR than for native visceral vessel stenosis. The proposed new velocity criteria define >= 70% ISR as >= 445 cm/s in stented SMAs and >= 289 cm/s in stented CAs.