Management of Venous Malformations

The Prospective Natural History Study of Patients with Intractable Venous Malformation and Klippel-Trenaunay Syndrome to Guide Designing a Proof-of-Concept Clinical Trial for Novel Therapeutic Intervention

Background: The natural history of venous malformation (VM) and Klippel-Trenaunay Syndrome (KTS) has not been quantitatively studied. To obtain benchmarks to guide designing clinical trials to assess safety and efficacy of novel drug candidates, the clinical course of the patients was followed for 6 months. Methods and Results: This is a multicenter prospective observational study evaluating the change rate in lesion volume from baseline with magnetic resonance images, as the primary endpoint. In addition, disease severities, performance status (PS), pain visual analog scale (VAS) score, quality of life (QoL), infections, and coagulation markers were also evaluated. Thirty-four patients (VM = 17, KTS = 17, 1-53 of age; median 15.9 years) with measurable lesion volume were analyzed. There was no statistically significant difference in the lesion volume between baseline and day 180, and the mean change rate (standard deviation) was 1.06 (0.28). There were no baseline characteristics that affected the change in lesion volume over 6 months. However, there were patients who showed more than 20% volume change and it was suggested that the lesion volume was largely impacted by local infection. There were no statistically significant changes in pain VAS score, severity, PS, QoL score, D-dimer, and platelet count over 6 months within all patients analyzed. Conclusion: The results showed the representative natural course of VM and KTS for a 6-month period with objective change of lesion volume and other factors, suggesting that it is scientifically reasonable to conduct a Phase 2 proof-of-concept study without a placebo arm, using the results of this study as the control. Clinical Trial Registration: NCT04285723, NCT04589650.

Dabigatran etexilate is efficacious in consumptive coagulopathy and pain associated with venous malformations

OBJECTIVE

Consumptive coagulopathy treatment and pain management are crucial for patients with venous malformations (VMs). Dabigatran etexilate, a non-vitamin K antagonist oral anticoagulant, has known advantages compared with low-molecular-weight heparin and vitamin K antagonists, including oral administration, a more consistent pharmacokinetics/pharmacodynamics profile, a better safety profile, and no need for coagulation surveillance. In the present study, we tested the efficacy and safety of dabigatran etexilate for consumptive coagulopathy treatment and pain management for patients with VMs.

METHODS

To investigate the efficacy and safety of dabigatran etexilate in treating localized intravascular coagulation (LIC) associated with VM, we retrospectively collected data for 19 outpatients with VM and LIC, who had been treated with dabigatran etexilate from September 2019 to June 2021. The patients provided oral informed consent and underwent biologic blood testing, routine examinations, and determination of coagulation function before and after treatment. The dosage of dabigatran etexilate was 110 mg twice daily for adults and 55 mg twice daily for children.

RESULTS

All 19 patients had benefited from dabigatran etexilate treatment with coagulation improvement and pain relief. Pain had improved in all 16 evaluable patients. The fibrinogen and D-dimer levels had improved in 18 of 19 patients. The fibrin degradation product level had improved in 10 of 14 patients. None of patients reported lesion regression, appearance changes, or improvement in mobility. No significant differences were found in the D-dimer, fibrinogen, and fibrin degradation product levels between the short-term (<10 days) and long-term (≥10 days) use of the medication. Dabigatran etexilate was well tolerated by all patients. No bleeding event had occurred during follow-up.

CONCLUSIONS

The results of our study have confirmed the efficacy and safety of dabigatran etexilate in treating pain and LIC in patients with VMs. Dabigatran etexilate is a suitable choice preoperatively to modify coagulation function and pain in patients with VMs.

Clinical results of polidocanol sclerotherapy in venous malformation treatment: Patient-perceived improvement and satisfaction

PURPOSE

This study evaluated the results of polidocanol sclerotherapy in the treatment of venous malformations (VM) including patient satisfaction, perceived improvement, and predictors of satisfaction.

MATERIAL AND METHOD

Patients with VM that underwent polidocanol foam sclerotherapy between June 2013 and July 2021 in a single center were retrospectively evaluated. Patient demographics, VM, and treatment characteristics were analyzed. Patient-reported outcomes and satisfaction were analyzed with a questionnaire.

RESULTS

This study included 232 (136, 58.6%, female) patients. The mean age was 24.49 ± 12.45 years (range 3-72). The clinical response rate was 82.3%. The rate of satisfaction was 82.3%, and 116 (50%) patients were significantly satisfied. There were no major complications. Clinical response and VM margin were related to satisfaction (p < 0.01, p = 0.012, respectively). Clinical response to pretreatment swelling was related to significant satisfaction (p = 0.02).

CONCLUSION

Polidocanol sclerotherapy was safe and effective in VM treatment with high satisfaction and low complication rates.