Short-Term Variability in Duplex-Derived Carotid Flow Parameters in Symptomatic Patients Awaiting Carotid
Maarten E Bodegom1, Rutger Hissink1, Mostafa El Moumni2
1Division of Vascular Surgery, Department of Surgery, Treant Zorggroep, Scheper Hospital, Emmen, The Netherlands.
Background:
Carotid stenosis is traditionally considered a relatively stable condition between symptom onset and carotid endarterectomy. However, short-term changes in duplex-derived hemodynamic parameters may occur during the waiting period and could influence preoperative assessment, particularly when surgery is delayed.
Methods:
A retrospective analysis was performed of a prospectively maintained single-center cohort of symptomatic patients undergoing carotid endarterectomy who had 2 comparable duplex ultrasound examinations: at presentation (DUS1) and 1 day prior to surgery (DUS2). Patients with an internal carotid artery peak systolic velocity (ICA PSV) ≥125 cm/sec at DUS1 were included. Changes in flow velocities and transitions between stenosis categories were evaluated. Predefined subgroup analyses were performed according to sex and timing of surgery (≤14 days vs. >14 days after the index neurological event).
Results:
The analytic cohort consisted of 632 symptomatic patients. Overall median ICA PSV did not change significantly between DUS1 and DUS2. In contrast, distal common carotid artery (CCA) PSV decreased modestly, resulting in a small but statistically significant increase in the ICA/CCA velocity ratio. Among patients with moderate stenosis at baseline (n = 146), 23.3% progressed to high-grade stenosis at repeat imaging, whereas 9.3% of patients with severe stenosis were reclassified as having moderate stenosis. Sex-specific analyses demonstrated a distinct pattern in women. Female patients undergoing surgery more than 14 days after the index event consistently demonstrated increasing ICA PSV between examinations, whereas women treated within 14 days showed relative stability. Male patients also exhibited increases in PSV during the waiting period, although these changes were less pronounced and less consistently associated with treatment delay.
Conclusion:
Short-term changes in duplex-derived carotid flow parameters can be detected in symptomatic patients awaiting carotid endarterectomy. While most patients remain within the same stenosis category between examinations, measurable changes in flow velocities occur in a substantial minority. In female patients with a moderate stenosis undergoing delayed surgery, increases in flow velocities were observed more consistently, although these changes did not invariably translate into reclassification to a higher stenosis category. These findings reinforce the importance of timely intervention and indicate that duplex ultrasound measurements should be interpreted as time sensitive rather than fixed values.
