Deep Vein Thrombosis-associated Venous Leg Ulcers: Outcomes Following Extirpation of Postthrombotic Obstructions Using Mechanical Thrombectomy

Introduction, Objectives, and/or Purpose:

Introduction: Postthrombotic syndrome (PTS) is a chronic and debilitating condition that occurs in up to 50% of patients with lower extremity deep vein thrombosis (DVT). After the acute phase of DVT, compositional remodeling of remaining thrombi leads to collagen-rich, postthrombotic obstructions (PTOs). Deep-vein PTOs can lead to persistent ambulatory venous hypertension and subsequent formation of venous leg ulcers (VLUs). Available therapies for PTS-associated VLUs are unable to remove and disrupt the structures that form in chronic PTOs, such as trabeculations, synechiae, and inflow lesions, which can also render stent placement ineffective. However, contemporary treatments for acute and nonacute DVT extraction are improving and may also aid in the treatment of recalcitrant VLUs through removal and disruption of PTOs.

Objectives: The goal of this study was to determine if patients with PTS secondary to prior DVT demonstrate VLU healing following mechanical thrombectomy.

Methods: This retrospective analysis includes all patients with DVT-associated VLUs referred to our center between August 2021 and May 2022 who were assessed to be candidates for the procedure. Mechanical thrombectomy with the ClotTriever System (Inari Medical, Irvine, California) was used in all cases. Characteristics and outcomes were collected, and technical success was defined as the ability to cross a lesion and introduce the thrombectomy device. Stents were placed in the iliac segment for outflow management in cases of compression or insufficient luminal gain with > 50% vessel area reduction by intravascular ultrasound (IVUS) evaluation. Clinical success was defined as a decrease from baseline to last follow-up of ≥ 1 ulcer diameter category (no VLU: 0; mild VLU [ < 2 cm]: 1, moderate VLU [2–6 cm]: 2, severe VLU [> 6 cm]: 3) on the revised venous clinical severity score (rVCSS) index.

Results: During the study period, 11 patients with 15 VLUs on 14 limbs were identified as candidates for mechanical thrombectomy. The mean age was 59.7 ± 11.8 years, and the patient population included 4 (36.4%) women (Table). The median VLU duration was 11.0 months, and the VLUs of 2 patients occurred secondary to DVT events that occurred > 40 years ago. At baseline, the VLU area was 13.6 ± 9.0 cm2, with a median rVCSS ulcer diameter category of 2. Technical success was achieved in 100% of the limbs. Adjunctive postthrombectomy venoplasty was performed in 13 (92.9%) limbs, and stents were placed in 10 (71.4%) limbs. As confirmed by postthrombectomy visual inspection and IVUS, a median of 5 passes with the ClotTriever catheter extracted or disrupted PTOs in all cases. No patients stayed in the hospital post thrombectomy due to the procedure, and there were no adverse events. Clinical success was achieved for all 15 VLUs, with the median rVCSS ulcer diameter category improving to 0. The time to VLU resolution or last follow-up was 12.8 ± 10.5 weeks, at which point the VLU area decreased to 0.5 ± 1.6 cm2, a 96.6% reduction compared to baseline on average. Healing was observed for all VLUs regardless of adjuvant stent placement. Twelve (80.0%) of the VLUs healed completely after a median of 10 weeks, and the 3 remaining VLUs demonstrated an area decrease of 83.1 ± 13.8% by last follow-up at a median of 12 weeks.

Conclusion(s): All patients in the study, regardless of adjunctive stent placement, showed complete or near-complete VLU healing within a few months of the mechanical thrombectomy procedure. The extirpation and interruption of deep-vein PTOs may have allowed for luminal gain and restoration of cephalad inflow. With further research, mechanical thrombectomy could prove to be a crucial component to successfully treating VLUs that form secondary to DVT.