OBJECTIVE:
This study aims to evaluate the
association between the degree of iliac venous outflow obstruction (IVOO) identified by Intravascular Ultrasound (IVUS) and venous reflux presentation in
lower limbs on Duplex Ultrasound (DU).
METHODS:
Patients with bilateral chronic
venous insufficiency, CEAP C3-6 (Clinical-
Etiology-
Anatomy-Pathophysiology
classification), and with Visual Analogic Scale score for
pain > 5, underwent DU for reflux evaluation deep venous system (reflux ≥ 1 s); superficial system, great
saphenous vein (GSV) and small
saphenous vein (SSV) (reflux ≥ 0.5 s); perforator system (reflux ≥ 0.35s). All
patients underwent IVUS in the iliac venous territory. The area of the impaired venous segments was categorized as obstructions< 50% (
Cat. 1); 50-79% (
Cat. 2), and ≥ 80% (
Cat. 3). Venous clinical severity scale (VCSS) and reflux multisegment score (RMS) were assessed.
RESULTS:
51
patients (n=102
limbs; 50.53 ± 14.5 years, 6
men) were included. The predominant clinical severity CEAP class was C3 in 54/102 (52.9%)
limbs. VCSS mean was 14.3 ± 6.7. Severe RMS (≥ 3) was registered in 63,4% of the
limbs. In 51/102
limbs (50%) presented
cat. 1, 27/102 (26.5%)
cat. 2, and 24/102 (23.5%)
cat. 3. Previous DVT was associated with critical obstruction (OR 3.65; 95% CI 1.29-10.38; p=0.015). Superficial and perforator venous systems had no
association with the degree of iliac obstruction. Deep venous reflux (DVR) had a significant
association with significative IVOO (obstruction ≥ 50%) (OR 6.44; 95% CI 2.19-18.93; p=0.001) and critical IVOO (obstruction ≥ 80%) (OR 4.57; 95% CI 1.70-12.27; p=0.003), and significant linear
association with IVOO degree and reflux in
femoral veins (p<0.001) and
popliteal vein (p=0.008). Significant lesions had 5.76 (95% CI 2.46-13.50; p<0.001) more odds of happening in the left
limb. After a
multivariate analysis, DVR remained as predictor for significant and critical obstruction (p<0.003, p< 0.012; respectively). Left
limb and previous DVT remained as predictors for IVOO ≥50% and IVOO≥ 80% (p<0.001, p=0.043; respectively)
CONCLUSIONS:
There is a significant linear
association between the degree of iliac venous outflow obstruction and reflux in the deep venous system on DU.
Limbs with DVR, severe RMS, loss of respiratory variation on DU, and previous DVT, were more likely to be affected by IVOO ≥ 50%, especially with the left
leg involvement.