Deep venous reflux definitions and associated clinical and physiological significance
Lim KH, Hill G, Tarr G, van Rij A. J Vasc Surg: Venous and Lym Dis.2013;1:325-332.
Classification validation as well as physiopathological significance of deep venous reflux (DVR) remains debated knowing that DVR is frequently combined with superficial venous reflux (SVR).
Numerous key questions need to be answered. First, does segmental deep reflux have an impact on CVD or not? Second, does segmental reflux location matter? In other words, do isolated common femoral vein reflux or popliteal vein reflux have the same physiopathological importance in terms of clinical and hemodynamic anomalies? Third, does SVR suppression abolish or improve DVR segmental and/ or axial reflux? Fourth, does operative treatment to restore valve competence of a single valve to improve axial reflux and hemodynamics?
Many articles referenced in the article by Lim et al that were devoted to answering the above questions and others, have been published, but, as underlined by the authors, in the absence of precise definitions, their conclusions are not clear and sometimes confusing.
To try to solve these questions, the New Zealand team suggested a new classification based on duplex ultrasound investigation determining, first, an axial level, which is slightly different from the Kistner classification, based on descending venography; second, to determine whether segmental reflux is limited to a single level or extended to multilevels without continuity with the axial vessel above the inguinal ligament.
This classification was correlated with:
- Clinical, Etiological, Anatomical, and Pathological (CEAP) classification, which the authors consider a valuable tool for evaluating clinical severity. However, even if in chronic venous insufficiency (CVI) the CEAP classification is frequently correlated with clinical severity, it seems that the use of the Venous Clinical Severity Score should have been more appropriate.1
- Venous filling index, measured by air plethysmography, as a tool for analyzing the severity of reflux—which is controversial.2
Some of their findings are in agreement with facts commonly acknowledged: DVR to knee or calf level is associated with more severe venous disease and greater hemodynamic derangement, independently of reflux in the superficial system. Others, such as the fact that segmental deep reflux over ≥2 levels is associated with more severe disease, must be confirmed.
In conclusion, this study provides valuable information on DVR, but as the only investigation used was duplex ultrasound, some nonpostthrombotic iliac compression could have been missed.
References
1. Vasquez MA, Rabe E, McLafferty RB, et al. Revision of the venous clinical severity score: Venous outcomes consensus statement: special communication of the American Venous Forum Ad Hoc Outcomes Working Group. J Vasc Surg. 2010;52:1387-1396.
2. Criado E, Farber MA, Marston WA, Daniel PF, Burnham CB, Keagy BA. The role of air plethysmography in the diagnosis of chronic venous insufficiency. J Vasc Surg. 1998;27:660- 670.