Vein dissection in a forearm AV fistula


This case shows how intraoperative Transit Time Flow Measurement (TTFM) and High-Frequency Ultrasound (HFUS) revealed a dissection in the outflow vein resulting in immediate revision.

Patient Information

  • 51-year-old male
  • 2019 myocardial infarction (LAD Stenting)
  • 2022 PCI (2 stents)
  • Hypertonus and Hyperlipidemia (Lipoprotein α: 107mg/dl)
    → Indication: Lipoprotein Apheresis

Intraoperative Completion Control

The surgical plan was to create a radio-cephalic side-to-end fistula. Preoperative vessel mapping showed a suitable artery and a good cephalic vein at the forearm. The initial TTFM (Figure 1) after the creation of the fistula showed acceptable flow but no thrill. The flow quickly decreased to values below 100 ml/min.

HFUS was used to identify the cause for the low flow revealing a dissection in the outflow vein proximal to the anastomosis. The videos below show the transverse view of the dissection including a floating vein valve and the longitudinal view visualizing the bloodstream pumping against an occlusion.

Transverse view


Longitudinal view


The resected vein was cut open to inspect the dissection (Figure 2). The Cimino fistula was abandoned, and a new forearm fistula was created more proximally (Figure 3).

The final TTFM showed adequate flow. There were also a good thrill and murmur (Figure 4 and Figure 5).


TTFM assisted in identifying flow issues and HFUS helped in identifying the problem. Final TTFM assured the surgeon that the flow was adequate for maturation of the fistula.

Technology used

Medistim MiraQTM Vascular System with Medistim TTFM probes and Medistim L15 Ultrasound Probe.

Case Attachments