SIR 2024
Renal and GU Interventions
Vishnu M. Chandra, MD
IR Resident
University of Virginia
Financial relationships: Full list of relationships is listed on the CME information page.
John F. Angle, MD
Professor
University of Virginia
Financial relationships: Full list of relationships is listed on the CME information page.
Venous stenoses and fibrin sheath formation are common causes of hemodialysis (HD) catheter failure. Catheter exchange is an effective treatment of a poorly functioning HD catheter. The current study evaluates the use of intravascular ultrasound (IVUS) to augment detection of these chronic complicating features and to facilitate catheter positioning when compared to venography alone.
Materials and Methods:
A single center prospective study (enrolled from 9/2019 to 6/2020), supported by Philips (Cambridge, MA), was performed in end stage renal disease (ESRD) patients undergoing chronic catheter-based hemodialysis. Inclusion criteria were adults presenting with a malfunctioning HD catheter placed greater than 14 days prior. Patients with active infection were excluded. IVUS and venography through the catheter were performed in all patients to evaluate for the cause of malfunction. Specifically, the presence and extent of a fibrin sheath, right atrial morphology, and presence of chronic stenoses were prospectively evaluated by both modalities. The impact of IVUS on diagnosis and procedural plan was also recorded. A paired sample t-test was used to compare anatomic distances calculated on IVUS vs. venography.
Results:
A total of 26 patients (18 female), with mean age of 62 years (32-81) were enrolled. The presence of a fibrin sheath was identified in 61.5% (16/26) of venograms, compared to 100% (26/26) with IVUS (p < 0.01). Anatomic measurement of the distance from carina to caudal extent of the fibrin sheath (by IVUS and venography) was available in 15/26 cases and the caudal extent of the fibrin sheath was significantly underestimated by venography (19.1 ± 28.5 mm on venography vs. 33.2 ± 14.0 mm on IVUS, p = 0.03). There was no significant difference in calculated distance from carina to the right atrial floor on venogram vs. IVUS. In 62% (16/26) of cases, operators reported a change in procedural plan after IVUS compared to venographic imaging alone. In 85% (21/26) of cases, operators reported the replaced catheter tip to be free of the fibrin sheath due to IVUS imaging compared to venography alone. There was a significant difference in the length of replaced catheters (replaced: 23.2 ± 3.4 cm vs 24.3 ± 2.6 cm, p = 0.01).
Conclusion:
IVUS helped better identify the caudal extent of catheter related fibrin sheaths when compared to venography alone. IVUS aided in more optimal positioning of catheters and may play an adjunctive role in hemodialysis catheter exchange in the appropriate patient.