SP509IN SEARCH OF AN OPTIMAL SCREENING PROGRAM FOR DETECTING STENOSIS AND PREDICTING INCIPIENT THROMBOSIS IN ARTERIOVENOUS GRAFTS

Le résumé fourni par la source

Introduction and Aims: Guidelines recommend that grafts should be screened for >50% stenosis (St) by surveillance (access blood flow [Qa], static venous pressure ratio [VAPR] or Duplex Ultrasound [D]) stating that there is insufficient evidence to prefer one technique from the other because no study has compared vis-à-vis all of the tools. To identify an optimal screening program, we compared the diagnostic performance for detecting angiographycally-proven St (StA) and predicting incipient thrombosis (within 3 mo) of Qa by ultrasound dilution (QaU) using the HD03 device, VAPR (according to Frinak et al) & D using the Logiq 7 device (to detect >50% St [StD] and to measure Qa [QaD]) in the same population of 57 upperarm grafts (46 with straight & 11 with loop configuration). Methods: Diagnostic performance was evaluated by the area under the ROC curve (AUC) & differences between AUCs by the DeLong test. Results: All tools showed a similar good performance for StA, with a AUC 0.87[95%CI 0.74-0.99] for StD (78% sensitivity [SE] & 4% false positives [FP]), 0.84[95%CI 0.78-0.98] for QaU (best threshold Qa<1300 ml/min: 78% SE & 13% FP), 0.79[95%CI 0.65-0.93] for VAPR (best threshold VAPR>0.9: 61% SE & 9% FP), & 0.70[95%CI:0.52-0.87] for QaD (best threshold Qa<1000 ml/min:60% SE & 29% FP). QaU was the best screening tool for prediciting thrombosis: AUC:0.83[95% CI 0.73-0.93] with best thresholds between Qa<1000 ml/min (60% SE & 16% FP) & Qa<1200 ml/min (80% SE & 24% FP). Its AUC was significantly higher (p<0.05) than that of StA (0.67[95%CI 0.55-0.77] with 70% SE & 35% FP) & VAPR (0.58[95%CI 0.42-0.74]: best threshold VAPR<0.6 with 30% SE & 21% FP). At logistic regression analysis QaU & VAPR were the only significant & independent predictors of thrombosis, with a 35%[95%CI 12-57] lower risk for each 100 ml/min above a Qa 400 ml/min (p=0.005) & a 5%[95%CI 1-9] lower risk for each 0.1 above a VAPR of 0.4 (p=0.04), respectively.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.