Table 1.

Complex criteria of a significant vs borderline stenosis—according to Malik et al. ¹³ and Ishii et al. ¹⁴

Significant	Borderline
Main criteria
Diameter reduction by >50%
Peak systolic velocity increase >2–3×
Additional criteria (≥1):
Residual diameter <1.9–2.0 mm	No additional criterion
Flow volume decrease by >25%a)
Flow volume <600 mL/min for AVGs, <500 mL/min for AVFs

If only the main criteria are present, the stenosis is borderline and reevaluation is indicated within 6–8 weeks. Significant stenoses are indicated to correction.

^a Flow volume decrease by >25% if the previous value was <1000 mL/min.