Servier – Phlebolymphology

XVII. Acute deep vein obstruction
invasive treatment

Mechanical thrombectomy in acute DVT – lessons learned
Michael Lichtenberg
In the ATTRACT study, after 24 months, patients receiving pharmacomechanical catheter-directed thrombolysis showed an improved result of treatment vs the patients not receiving pharmacomechanical catheter-directed thrombolysis (Vilalta score, 3.95 vs 5.54 [P=0.03]; venous clinical severity score, 1.98 vs 2.8 [P=0.018]; VEINES score, 28.63 vs 23.02 [P=0.029]). Frequency of bleeding complications in the PEARL registry was 4.5% (minor/major), in the CAVENT study 22% (minor/major), and in the Venous registry 16% minor and 11% major. A meta-analysis (review included 19 articles) of catheter-directed thrombolysis or ultrasound catheter-directed thrombolysis and pharmacomechanical thrombectomy with AngioJet, Pneumbra Indigo, or Aspirex devices showed a nonsignificant differences between lysis grade II/III, rates of recurrent deep vein thrombosis, overall post-thrombotic rate, moderate/severe post-thrombotic syndrome, reflux rate, and adjunctive angioplasty and stenting. Only in cases of frequent major bleeding complications was pharmacomechanical thrombectomy significantly favored. Therefore, pharmacomechanical thrombectomy and catheter-directed thrombolysis are similar in efficacy, but, with pharmacomechanical thrombectomy, the trend moves toward lower overall post-thrombotic syndrome and reflux.

The issue of the venous stenting in acute DVT patients
Haraldur Bjarnason (US)
In a registry of lower limb deep vein thrombosis treated with catheter-directed thrombolysis at 63 centers, 99 of 303 treated limbs (32.6%) had stents placed. There were no data about post-thrombotic syndrome in the long-term outcomes. In the CAVENT trial (2012), ATTRACT trial (2017) and Avgerinos study, the frequency of stenting and post-thrombotic syndrome was 18%/43% (5 years), 28%/47% (2 years), and 100%/14.4% (5 years) accordingly. The mid-term results of CAVENT showed that in the stenting group (n=40), 32 (80%) patients were free of post-thrombotic syndrome, but, in the no stenting group (n=33), there were only 13 (39%) with post-thrombotic syndrome. In conclusion, following successful thrombus removal from the iliac veins, any significant remaining obstruction should be treated with stents.

Who should we treat by local thrombolysis/thrombus removal after ATTRACT trial result publication?
Antonious Gasparis (US)
The results of the ATTRACT trial were published in 2017 and are widely known. The ATTRACT trial previously reported that pharmacomechanical catheter-directed thrombolysis (PCDT) did not prevent post-thrombotic syndrome in patients with acute proximal deep vein thrombosis. However, catheter-based strategies of thrombus removal are focused on patients with iliofemoral deep vein thrombosis (not femoropopliteal); therefore, the results from patients with iliofemoral deep vein thrombosis will be the most meaningful in guiding patient care. In the subanalysis, the effect of PCDT in ATTRACT patients with iliofemoral deep vein thrombosis, a subgroup of 391 patients with acute deep vein thrombosis involving the iliac or common femoral veins were randomized to PCDT with anticoagulation vs anticoagulation alone (no PCDT). The patients were observed for 24 months to compare short-term and long-term outcomes. Between 6 and 24 months, there was no difference in the occurrence of post-thrombotic syndrome (Villalta scale ≥5 or ulcer, 49% PCDT vs 51% no PCDT; P=0.59). PCDT led to a reduction in post-thrombotic syndrome severity as shown by lower mean Villalta and venous clinical severity scores (P<0.01 for comparisons at 6, 12, 18, and 24 months), and fewer patients with moderate or- severe post-thrombotic syndrome (Villalta scale ≥10 or ulcer, 18% vs 28%; P=0.021) or severe post-thrombotic syndrome (Villalta scale ≥15 or ulcer, 8.7% vs 15%; P=0.048 and venous clinical severity score ≥8, 6.6% vs 14%; P=0.013). From baseline, PCDT led to a greater reduction in leg pain and swelling (P<0.01 for comparisons at 10 and 30 days) and a greater improvement in venous disease–specific quality of life (venous insufficiency epidemiological and economic study quality of life unit difference 5.6 through 24 months; P=0.029), but no difference in generic quality of life (P>0.2 for comparisons of SF-36 mental and physical component summary scores through 24 months). In patients having PCDT vs no PCDT, major bleeding within 10 days occurred in 1.5% vs 0.5% (P=0.32), and recurrent venous thromboembolism over 24 months was observed in 13% vs 9.2% (P=0.21). In case of patients with acute iliofemoral deep vein thrombosis, PCDT did not influence the occurrence of post-thrombotic syndrome or recurrent venous thromboembolism. However, PCDT significantly reduced early leg symptoms and, over 24 months, reduced post-thrombotic syndrome severity scores, reduced the proportion of patients who developed moderate-or-severe post-thrombotic syndrome and resulted in a greater improvement in venous disease–specific quality of life. Consequently, we should treat patients with iliofemoral deep vein thrombosis with moderate or severe symptoms with local thrombolysis or thrombus removal and understand that patients with femoropopliteal deep vein thrombosis will not has benefit from PCDT.