Comprehensive Analyses of Coagulation Parameters in Patients with Vascular Anomalies

BACKGROUND

Vascular anomalies comprise a diverse group of rare diseases with altered blood flow and are often associated with coagulation disorders. The most common example is a localized intravascular coagulopathy in venous malformations leading to elevated D-dimers. In severe cases, this may progress to a disseminated intravascular coagulopathy with subsequent consumption of fibrinogen and thrombocytes predisposing to serious bleeding. A separate coagulopathy is the Kasabach-Merritt phenomenon in kaposiform hemangioendothelioma characterized by platelet trapping leading to thrombocytopenia and eventually consumptive coagulopathy. Our previous work showed impaired von Willebrand factor and platelet aggregometry due to abnormal blood flow, i.e., in ventricular assist devices or extracorporeal membrane oxygenation. With altered blood flow also present in vascular anomalies, we hypothesized that, in particular, the von Willebrand factor parameters and the platelet function may be similarly impacted.

METHODS

We prospectively recruited 73 patients with different vascular anomaly entities and analyzed their coagulation parameters.

RESULTS

Acquired von Willebrand syndrome was observed in both of our patients with Kasabach-Merritt phenomenon. In six out of nine patients with complex lymphatic anomalies, both the vWF antigen and activity were upregulated. Platelet aggregometry was impaired in both patients with Kasabach-Merritt phenomenon and in seven out of eight patients with an arteriovenous malformation.

CONCLUSIONS

The analysis of coagulation parameters in our patients with vascular anomalies advanced our understanding of the underlying pathophysiologies of the observed coagulopathies. This may lead to new treatment options for the, in part, life-threatening bleeding risks in these patients in the future.

Coagulopathy and related complications following sclerotherapy of congenital venous malformations

BACKGROUND

Congenital venous malformations (VMs) are low-flow vascular anomalies that can cause coagulation abnormalities. This phenomenon, referred to as localized intravascular coagulopathy (LIC), is characterized by elevated D-dimer, hypofibrinogenemia, and/or thrombocytopenia. Increased risk for LIC includes patients with an extensive VM, multifocal VM, and Klippel-Trenaunay and CLOVES syndromes. Peri-procedural anticoagulation has been given to prevent complications from LIC in patients undergoing surgical/interventional procedures; however, the rate of clinically relevant complications from sclerotherapy is largely unknown. The purpose of this study is to describe a single-institution's incidence of LIC in patients with VMs and coagulopathy-related complications following sclerotherapy.

DESIGN/METHODS

Retrospective chart review of patients, 0-21 years of age, with VM who underwent sclerotherapy without peri-procedural anticoagulation and had coagulation profiles evaluated within 1 month prior to sclerotherapy.

DATA COLLECTED

diagnosis type (high vs. low risk for LIC), coagulation profile (including PT/PTT, D-dimer, fibrinogen, and platelet count), sclerosant used, and post-procedure outcomes. Coagulopathy-related complications included clinically relevant bleeding, deep vein thrombosis (DVT), and pulmonary embolism (PE).

RESULTS

N = 138 patients; 59.4% were female. The most common location of VM was the lower extremity (47.8%; 66/138). Of patients with high-risk VMs (29/138 [21%]), 11/29 (37.9%) had laboratory values consistent with LIC, whereas 5% (5/109) of low-risk VMs had LIC. In sum, 492 sclerotherapy procedures were performed with no complications of bleeding, DVT, or PE.

CONCLUSION

Patients undergoing sclerotherapy for VM with abnormal coagulation profiles may not require peri-procedural low molecular weight heparin (LMWH). Further studies are needed to precisely define which patients would benefit from anticoagulation.

Venous malformations with severe localized intravascular coagulopathy treated with microwave ablation

OBJECTIVES

To evaluate the safety and feasibility of microwave ablation for treating venous malformations (VMs) with severe localized intravascular coagulopathy (LIC).

PATIENTS AND METHODS

Data for patients with the diagnosis of VMs coupled with severe LIC who underwent color Doppler-guided microwave dynamic ablation between January 2017 and June 2019 were retrospectively reviewed and analyzed. All patients had previously received sclerotherapy or other treatments with poor outcomes and gradual aggravation of coagulation abnormalities. Microwave treatment with "dynamic ablation" was performed with real-time color Doppler monitoring and was repeated if necessary after 3 months. Low-molecular-weight heparin (LMWH) was used to control consumptive coagulopathy. The therapeutic efficacy including coagulation function and lesion size was evaluated using the four-level scale developed by Achauer.

RESULTS

Among 15 patients with extensive diffuse or multiple VMs, 10 patients presented with lesions in a single lower extremity, one in both lower extremities and the perineum, one in both upper extremities and the trunk, and three with multiple lesions. The patients underwent a total of 74 microwave ablation sessions, with an average of 4.9 sessions per person. Coagulation abnormalities were temporarily aggravated in 59 sessions within the first seven days post-ablation but improved to grade II (fair) a week later. From six months to three years after the ablation, the lesions improved to grade IV (excellent) in one patient, grade III (good) in six patients, and grade II (fair) in eight patients. Moreover, the coagulation function improved to grade IV in four patients, grade III in eight patients, and grade II in three patients, resulting in an efficiency rate of 80% (12/15). Post-ablation complications included fever, hemoglobinuria, and elevations in aspartate aminotransferase, lactate dehydrogenase, and alanine aminotransferase. The patients with fever and hemoglobinuria recovered after specific therapeutic measures, but elevations in aspartate aminotransferase, lactate dehydrogenase, and alanine aminotransferase recovered spontaneously without further interventions.

CONCLUSIONS

Ablation coupled with anticoagulation can effectively treat VMs in patients with severe LIC and improve the long-term coagulation function.

Localized intravascular coagulation in venous malformations: A system review

Venous malformation is one of the slow-flow vascular malformations. Dysfunction of coagulation often occurs in most venous malformations, especially the diffuse and multifocal lesions, referred to as localized intravascular coagulopathy. It is characterized by the elevation of D-dimers and fibrin degradation products, low levels of fibrinogen, FV, FVIII, FXIII, and antithrombin III, and sometimes minor-to-moderate thrombocytopenia. Here we reviewed the clinical manifestations, pathogenesis, diagnosis, and treatment of localized intravascular coagulopathy in venous malformations.

Effectiveness and Safety of Treatment with Direct Oral Anticoagulant Rivaroxaban in Patients with Slow-Flow Vascular Malformations: A Case Series

BACKGROUND

Slow-flow vascular malformations (VM) can be associated with localized intravascular coagulopathy (LIC) that is characterized by elevated D-Dimer levels and low fibrinogen and platelets. This can lead to bleeding and clotting tendencies, which can give rise to functional limitations such as pain and swelling and even progress to disseminated intravascular coagulopathy.

METHODS AND RESULTS

We conducted a chart review of four patients with evidence of LIC who were started on rivaroxaban. We found an improvement of D-Dimer and/or fibrinogen levels in all four patients. They also had an improvement of pain and functionality.

CONCLUSIONS

We report on four patients in whom anticoagulation with a direct oral anticoagulant, rivaroxaban, was effective in controlling signs and symptoms of consumptive coagulopathy with no evidence of bleeding from the use of rivaroxaban.

Septic shock due to infected giant venous malformation complicated by massive bleeding

Case

A 19-year-old man with a hemangioma that extended from the left arm to the axillary region had deteriorated due to shock, and no improvement was observed after fluid resuscitation. His status on arrival led to complications of hemorrhagic and septic shock with his left arm swollen and deep purple in color. Left arm amputation to control the source of bleeding and infection was thought to be indicated, however, the coagulation system had collapsed. Therefore, initial reduction of the blood flow to the hemangioma with angiographic endovascular treatment was carried out. Thereafter, continuous hemodiafiltration using a polymethylmethacrylate membrane hemofilter against hypercytokinemia was introduced in the intensive care unit for damage control, which resulted in success.

Outcome

We completed the arm amputation, and subsequently carried out a latissimus dorsi muscle flap transfer on the amputated stump. The patient achieved an ambulatory discharge.

Conclusions

We successfully treated the very rare case of massive venous malformation with shock due to hemorrhage and infection by performing damage control.