This prospective study evaluated a novel risk score based on Vasc-Alert surveillance to identify hemodialysis vascular access with significant stenosis. Patients receiving hemodialysis using arteriove..
This prospective study evaluated a novel risk score based on Vasc-Alert surveillance to identify hemodialysis vascular access with significant stenosis. Patients receiving hemodialysis using arteriovenous access with Vasc-Alert scores ≥8 (high score) or ≤ 3 (low score) were prospectively enrolled. Each patient was screened for clinical symptoms of access dysfunction, received a physical examination and a point of care ultrasound scan of the access arm. Subjects were referred to angiogram by the primary care team as per clinical necessity. Clinical monitoring (CM) includes clinical symptoms and signs. Luminal narrowing > 50% found by ultrasound or angiogram is considered significant. A total of 38 patients [20 in the high score (HS) group and 18 in the low score (LS) group] were enrolled. There is no significant difference in age, gender, diabetes, and hypertension between the groups (all p>0.10), while the LS group had a higher prevalence of coronary artery disease (55% vs. 25%, p=0.05). CM is positive in 60% of HS vs. 39% in LS (p=0.19). HS group is more likely to have significant stenosis than those in the LS group (65% vs. 17% p=0.003). Only 58% of subjects with positive CM have significant stenosis (11 of 19). A total of 19 patients had no positive CM findings. HS alone identified 4 out of these 19 patients with significant stenosis (p=0.05). Adjusted for risk score, a positive CM finding, and prior stenotic history were not significantly associated with significant stenosis. Every unit increase in the score was associated with 34% higher odds of stenosis (adjusted odds ratio [aOR] = 1.34; 95% confidence interval [95% CI]: 1.05- 1.70; P=0.02). The HS group is associated with 7-fold higher stenosis odds than the LS group after adjustment (aOR=7.38; 95% CI: 1.44-37.82; p=0.02). The sensitivity and specificity of the HS group in identifying stenosis are 81% and 68%, respectively. The positive predictive value of HS is 0.65%, and the negative predictive value is 0.83. The Vasc-Alert score predicts stenotic hemodialysis vascular access with high reliability. The score provides an objective measure for risk stratification even in those without positive CM findings.