Extensive venous/lymphatic malformations causing life-threatening haematological complications

Utilization of Healthcare Resources by Vascular Anomaly Patients: An Assessment of Healthcare Burden by Lesion Complexity

Background

Vascular anomalies (VAs) are heterogeneous lesions. Symptoms vary widely by lesion type and complexity. VA patients often require life-long interdisciplinary care; however, there is a paucity of data on the healthcare utilization of VA patients, and their burden on the healthcare system remains largely unquantified. We hypothesize that healthcare utilization by complex lymphatic malformation (LM) and venous malformation (VM) patients will be significantly higher compared with simple LM and VM patients.

Methods

A retrospective, longitudinal study was performed of LM/VM patients seen through multidisciplinary VA clinics between January 1, 2019 and December 31, 2020. Data were collected from each patient's first presentation through December 31, 2021 and included number of office visits, imaging studies, specialists involved, procedures, hospitalization data, and approximate costs, normalized to per year utilization. Patients were divided into "simple" and "complex" LMs/VMs. Involvement of the airway, more than one anatomic area, and/or complex lymphatic anomalies were defined as "complex."

Results

In total, 28 simple and 29 complex LM patients and 51 simple and 18 complex VM patients were identified. Complex LM and VM patients had significantly higher numbers of imaging studies, specialists involved, procedures and hospitalizations, and costs incurred. Complex LM patients also had significantly higher per year office visits.

Conclusions

VA care is chronic and costly, especially for complex LM/VM patients. LM/VM complexity was a predictor for increased inpatient and outpatient healthcare utilization and higher costs. Better awareness of the healthcare utilization trends of LM/VM patients will allow for improved counseling for these patients regarding prognosis and expectations.

Pathophysiology of Slow-Flow Vascular Malformations: Current Understanding and Unanswered Questions

Background

Slow-flow vascular malformations include venous, lymphatic, and lymphaticovenous malformations. Recent studies have linked genetic variants hyperactivating either the PI3K/AKT/mTOR and/or RAS/RAF/MAPK signaling pathways with slow-flow vascular malformation development, leading to the use of pharmacotherapies such as sirolimus and alpelisib. It is important that clinicians understand basic and translational research advances in slow-flow vascular malformations.

Methods

A literature review of basic science publications in slow-flow vascular malformations was performed on Pubmed, using search terms "venous malformation," "lymphatic malformation," "lymphaticovenous malformation," "genetic variant," "genetic mutation," "endothelial cells," and "animal model." Relevant publications were reviewed and summarized.

Results

The study of patient tissues and the use of primary pathogenic endothelial cells from vascular malformations shed light on their pathological behaviors, such as endothelial cell hyperproliferation and disruptions in vessel architecture. The use of xenograft and transgenic animal models confirmed the pathogenicity of genetic variants and allowed for preclinical testing of potential therapies. These discoveries underscore the importance of basic and translational research in understanding the pathophysiology of vascular malformations, which will allow for the development of improved biologically targeted treatments.

Conclusion

Despite basic and translation advances, a cure for slow-flow vascular malformations remains elusive. Many questions remain unanswered, including how genotype variants result in phenotypes, and genotype-phenotype heterogeneity. Continued research into venous and lymphatic malformation pathobiology is critical in understanding the mechanisms by which genetic variants contribute to vascular malformation phenotypic features.

How we approach localized vascular anomalies

Vascular anomalies are a group of disorders divided into two distinct subtypes: vascular tumors and vascular malformations. Vascular tumors are proliferative in nature, while malformations are nonproliferative. Simple, localized vascular malformations refer to a group of malformations that are localized to a single area of involvement. These simple malformations include capillary, lymphatic, venous, and arteriovenous malformations. The pediatric hematologists and oncologists are becoming increasingly involved in the diagnosis and management of these disorders. This review presents four cases as a means to discuss the diagnosis, clinical and imaging features, and management strategies of simple, localized vascular malformations.

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.

Interventional Treatment Options in Children with Extracranial Vascular Malformations

Extracranial vascular malformations vary greatly and belong to the complex field of orphan diseases and can involve all segments of the vascular tree: arteries, capillaries, and veins, and similarly the lymphatic system. The classification according to the International Society for the Study of Vascular Anomalies (ISSVA) represents an important guidance for selecting appropriate therapy. Although many of the principles of endovascular treatment, including image-guided sclerotherapy and embolization, are similar in adult and pediatric practice, there are some distinct differences regarding the treatment of vascular malformations of children. Thus, it is crucial to involve longer-term plan about managing these chronic diseases and their impact on a growing child. This review provides a detailed overview over the clinical presentation of venous, lymphatic, and arteriovenous malformations in children and emphasizes the specifics of their interventional treatment options, including distinct pediatric dose limitations and procedure-related side effects.

Imaging of peripheral vascular malformations - current concepts and future perspectives

Vascular Malformations belong to the spectrum of orphan diseases and can involve all segments of the vascular tree: arteries, capillaries, and veins, and similarly the lymphatic vasculature. The classification according to the International Society for the Study of Vascular Anomalies (ISSVA) is of major importance to guide proper treatment. Imaging plays a crucial role to classify vascular malformations according to their dominant vessel type, anatomical extension, and flow pattern. Several imaging concepts including color-coded Duplex ultrasound/contrast-enhanced ultrasound (CDUS/CEUS), 4D computed tomography angiography (CTA), magnetic resonance imaging (MRI) including dynamic contrast-enhanced MR-angiography (DCE-MRA), and conventional arterial and venous angiography are established in the current clinical routine. Besides the very heterogenous phenotypes of vascular malformations, molecular and genetic profiling has recently offered an advanced understanding of the pathogenesis and progression of these lesions. As distinct molecular subtypes may be suitable for targeted therapies, capturing certain patterns by means of molecular imaging could enhance non-invasive diagnostics of vascular malformations. This review provides an overview of subtype-specific imaging and established imaging modalities, as well as future perspectives of novel functional and molecular imaging approaches. We highlight recent pioneering imaging studies including thermography, positron emission tomography (PET), and multispectral optoacoustic tomography (MSOT), which have successfully targeted specific biomarkers of vascular malformations.

Characteristics, clinical presentation, and treatment outcomes of venous malformation in the extremities

OBJECTIVE

The clinical presentation of venous malformations (VMs) is variable and not well documented. The present study was designed to determine the clinical characteristics and outcomes in association with the type and extent of VM in the extremities.

METHODS

Patients with a diagnosis of a VM using ultrasound, computed tomography, or magnetic resonance imaging were included in the present study. The VM extent and tissue involvement, signs, and symptoms were retrospectively collected. Those with arteriovenous malformations, Klippel-Trenaunay syndrome, lymphedema, and symptoms from other unrelated diseases were excluded. The VMs were classified as extensive or localized according to whether different tissues or the entire compartment was involved. The clinical outcomes and imaging studies were obtained for both the treated patients and those who had chosen to not undergo any intervention.

RESULTS

A total of 72 patients, of whom 26 were men, were included in the present study, with a median age of 30 years. The VM had extended into the subfascial space in 40 patients (55.6%). Patients with VM distributed on their leg had mostly experienced pain, which was more evident during physical activity (n = 40; 80.0%), with swelling worsening with prolonged standing (n = 35; 70.0%). For those with VMs in the upper extremities, the most prominent complaints were venous enlargement (n = 10; 45.5%), pain (n = 9; 40.9%), and swelling (n = 11; 50.0%). The symptoms were related to the extent of the lesion (odds ratio, 7.664; 95% confidence interval, 2.006-29.291; P = .003). Treatment was decided by the extent and depth of the lesions. Excision was performed in 15 patients (20.8%), sclerotherapy in 12 (16.7%), sclerotherapy with phlebectomy or coil embolization in 8 (11.1%), and stripping in 2 (2.8%). An excellent result was achieved with the treatment of localized VMs. For those with extensive VMs, the symptom intensity was reduced or controlled after multiple treatments.

CONCLUSIONS

VMs of the extremities affect patients' quality of life significantly owing their appearance and the resulting pain. The VM extent was associated with symptom severity. The clinical outcomes have been excellent for localized VMs; however, extensive VMs will require multiple treatments to reduce the symptom intensity.

Venous Malformations and Blood Coagulation in Children

Introduction: Venous malformations (VMs) are congenital low-flow lesions with a wide spectrum of clinical manifestations. An increasing number of studies link VMs to coagulation abnormalities, especially to elevated D-dimer and decreased fibrinogen. This condition, termed localized intravascular coagulopathy (LIC), may pose a risk for hemostatic complications. However, detailed data on the laboratory variables for coagulation and fibrinolytic activity in VM patients are limited. We addressed this question by systematically analyzing the coagulation parameters in pediatric VM patients. Methods: We included 62 patients (median age 11.9 years) with detailed laboratory tests for coagulation and fibrinolytic activity at a clinically steady phase. We assessed clinical and imaging features of VMs and their correlations with coagulation and fibrinolysis variables using patient records and MRI. Results: D-dimer was elevated in 39% and FXIII decreased in 20% of the patients, as a sign of LIC. Elevated D-dimer and decreased FXIII were associated with large size, deep location, and diffuse and multifocal VMs. FVIII was elevated in 17% of the patients and was associated with small VM size, superficial and confined location, discrete morphology, and less pain. Surprisingly, antithrombin was elevated in 55% of the patients but without associations with clinical or other laboratory variables. Conclusions: LIC was common in pediatric patients with VMs. Our results provide a basis for when evaluating the risks of hemostatic complications in children with VMs. Further research is warranted to explore the mechanisms behind coagulation disturbances and their relation to clinical complications.

Factors influencing quality of life in children with low-flow vascular malformations: a qualitative study using focus groups

BACKGROUND

Very few studies have evaluated the quality of life (QoL) of children suffering from low-flow vascular malformations. This is the first study investigating the influencing factors.

OBJECTIVES

To identify the factors influencing QoL in children with low-flow vascular malformations.

METHODS

We conducted a qualitative study employing focus group interviews (Clinical Trials Number: NCT03440827). The study was a prospective, interventional, non-comparative, multicentre study performed in four expert centres for vascular anomalies. Qualitative data about personal experiences, feelings, difficulties, needs and various factors influencing behaviours were collected. Theme-based content analysis (manual and specialist textural software guided) were used to analyse the verbatim transcripts of all focus group sessions. Manual qualitative discourse analysis was performed to identify the different themes and categories. Informatics' analyses were subsequently performed for each individual category.

RESULTS

Ten focus groups (26 individuals including 10 children aged 11 to 15 years) were conducted until saturation. Influencing factors were related to 4 categories: medical care, self-image, social impact on daily activities and challenging social relationships. These factors were responsible for intrafamily upheavals and may lead to future identity-building problems.

CONCLUSIONS

This study provides an essential framework from which physicians can develop strategies to improve patient care and quality of life. These data may also be useful to develop specific age-sensitive QoL questionnaires.

[Overt disseminated intravascular coagulation complicating a venous malformation]

INTRODUCTION

Coagulopathy related to venous malformations can be life threatening. This complication is little known and underestimated.

CASE REPORT

We report the case of a 52-year-old female patient who presented with a left femoral fracture. She had a pre-existing muscular infiltrating venous malformation of the left hip. During surgery, she developed acute disseminated intravascular coagulation. The latter was probably a consequence of both surgery and localized intravascular coagulation that was unknown before the trauma.

CONCLUSION

It is important to diagnose localized intravascular coagulation in venous malformations, since the risk of disseminated intravascular coagulation can be prevented by anticoagulant therapy.

Peri-procedural Anticoagulation in Patients with Head and Neck Versus Extremity Venous Malformations

OBJECTIVE

(1) Review a multidisciplinary vascular anomalies center's practice regarding periprocedural anticoagulation for venous malformations (VM) and the associated risk of thromboembolic and disseminated intravascular coagulation (DIC) events. (2) Compare the risk of thromboembolic events and DIC post-procedure between head and neck (H&N) and extremity VM patients.

METHODS

An Institutional Review Board (IRB)-approved, retrospective chart review was performed on 120 VM patients. A thromboembolic event was defined as a thrombus formation post-sclerotherapy or post-surgery within 2 months in a distant or local venous structure not directly addressed by the procedure.

RESULTS

There were 39 cases involving the H&N and 81 cases based at the extremities. There were eight cases of post-procedure thrombus formation within the extremity VM group (8/71; 11.3%) as opposed to 0 cases in the H&N group (OR: 0, 95% CI .00-.09), p = .049. There was no difference in incidence of post-procedure thromboembolic events between those with elevated D-dimer (H&N: 0%, extremity: 22.7%, 5/22) and normal D-dimer values (H&N: 0%, extremity: 6.3% [1/16], P = .370). There was no difference in incidence of post-procedure thromboembolic events between those who received periprocedural anticoagulation (H&N: 0%, extremity: 21%, 4/19) and those who did not (H&N: 0%, extremity: 8.2%, 4/49), (Extremity: OR: 3.00, .67-13.50, P = .206).

CONCLUSION

Post-procedure thromboembolism is rare in the treatment of venous malformations, especially in the head and neck subsite. Regardless of anticoagulation use, there were no thromboembolic events for H&N VM patients. Such events are rare, and the odds may approach zero, especially with small sample size.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:1163-1167, 2021.

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.

Localised intravascular coagulation complicating venous malformations in children: Associations and therapeutic options

Venous malformations are slow-flow congenital vascular malformations that enlarge as the child ages and may be associated with localised intravascular coagulation, a consumptive coagulopathy characterised by elevated D-dimer and decreased fibrinogen levels. The authors review the known correlations between localised intravascular coagulation and venous malformation number, size and planes involved, and call attention to the concept of the progression of localised intravascular coagulopathy as the child ages and their venous malformations enlarge. The authors also discuss the identified therapeutic options for its investigation, management and treatment, including compression garments, anti-coagulation therapy, sclerotherapy, endovascular laser, surgical excision and sirolimus (rapamycin). Evidence for protocol improvements that may be instigated for the optimal physical and medical therapy of venous malformations complicated by localised intravascular coagulopathy is reviewed.

Venous Thromboembolism in Pediatric Vascular Anomalies

The presence of a vascular anomaly suggests that capillaries, veins, arteries, and/or lymphatic vessels have demonstrated abnormal development and growth. Often dilated and misshaped, these vessels augment normal flow of blood and lymphatic fluids that increases the overall risk to develop intralesional thrombosis. Abnormal endothelial and lymphoendothelial cells activate hemostasis and hyperfibrinolytic pathways through poorly understood mechanisms, which contribute to the development of localized intravascular coagulopathy. Vascular malformations, tumors, and complex combined syndromes demonstrate varying degrees of prothrombotic activity and consumptive coagulopathy depending on the vessels involved and the pattern and extent of abnormal growth. The clinical impact of venous thromboembolism in pediatric vascular anomalies varies from painful syndromes that disrupt quality of life to life-threatening embolic disease. There remains little literature on the study, evaluation, and treatment of thrombosis in pediatric vascular anomalies. However, there have been great advances in our ability to image complex lesions, to surgically and interventionally augment disease, and to provide enhanced supportive care including patient education, compression therapy, and strategic use of anticoagulation.

MRI phenotypes of localized intravascular coagulopathy in venous malformations

BACKGROUND

The incidence of localized intravascular coagulopathy (LIC) in venous malformations varies with lesion size and location, as well as the presence of palpable phleboliths. The development of LIC can cause pain and hemorrhage and can progress to disseminated intravascular coagulopathy (DIC) and thromboembolic disease resulting in death in some cases. Early recognition of LIC can relieve symptoms and prevent progression to life-threatening complications.

OBJECTIVE

The aim of this work was to identify MRI features of venous malformation associated with LIC. We hypothesized that venous malformations with larger capacitance, slower flow and less physiological compression (greater stasis) were more likely to be associated with LIC.

MATERIALS AND METHODS

In this HIPAA-compliant and IRB-approved study, we retrospectively reviewed clinical records and MRI for consecutive patients undergoing evaluation of venous malformations at our multidisciplinary Birthmarks and Vascular Anomalies Center between 2003 and 2013. Inclusion required consensus diagnosis of venous malformation and availability of laboratory data and MRI; patients on anticoagulation or those previously undergoing surgical or endovascular treatment were excluded. LIC was diagnosed when D-dimer exceeded 1,000 ng/mL and/or fibrinogen was less than 200 mg/dL. Two board-certified radiologists assessed the following MRI features for each lesion: morphology (spongiform vs. phlebectatic), presence of phleboliths, size, location (truncal vs. extremity), and tissue type(s) involved (subcutis, muscle, bone and viscera). Univariate logistic regression analyses were used to test associations between LIC and MRI findings, and stepwise regression was applied to assess the significance of the individual imaging predictors.

RESULTS

Seventy patients, 37 with LIC, met inclusion criteria during the 10-year study period (age: 14.5 +/- 13.6 years [mean +/- standard deviation]; 30 male, 40 female). Both elevated D-dimer and low fibrinogen were associated with the presence of phleboliths, larger lesion sizes and visceral involvement on MRI (all P < 0.05). In stepwise regressions, lesion size (P < 0.001), the presence of phleboliths (P = 0.005) and lesion morphology (P = 0.006) were all significant predictors of LIC.

CONCLUSION

LIC is associated with larger lesion size, visualized phleboliths, truncal location and spongiform morphology on MRI in venous malformations, suggesting that lesions with larger capacitance, slower flow and less physiological compression are more likely to be associated with coagulopathy.

Rapidly involuting congenital hemangioma associated with profound, transient thrombocytopenia

Rapidly involuting congenital hemangioma (RICH) is an uncommon, often high-flow vascular tumor that presents at birth and involutes within the first year of life. It is clinically and histologically distinct from infantile hemangioma, kaposiform hemangioendothelioma, and tufted angioma, the latter two being associated with Kasabach-Merritt phenomenon. We present a female infant with RICH and profound, transient thrombocytopenia and review the extent and clinical course of thrombocytopenia in the context of congenital vascular tumors.

Venous malformation and haemangioma: differential diagnosis, diagnosis, natural history and consequences

Venous malformation (VM) is the most common form of congenital vascular malformation (CVM). VM presents at birth as an inborn vascular defect and never disappears/regresses spontaneously through the rest of life; it will continue to grow slowly at a rate that is proportional to the growth rate of the body. Haemangioma is not a vascular malformation but one of the vascular tumours originating from the endothelial cells; it develops after birth mostly in the infantile/neonatal period with a distinctive growth cycle: a proliferation phase of early rapid growth followed by an involutional phase of slow regression. Although the vascular malformation and vascular tumour belong to the ‘vascular anomaly’ together, both conditions are fundamentally different not only in their anatomical, histological and pathophysiological findings but also in their clinical courses. Therefore, an appropriate differential diagnosis of the VM is mandated not only from other kinds of CVMs but also from ‘genuine’ haemangioma. Appropriate diagnosis and assessment of VMs can be made based on clinical presentation and a proper combination of basic non-invasive studies in general but the presence of a mixed lesion involving other types of CVM lesions and the type of VM lesion, extratruncular and truncular, will dictate the need for further work-up with additional non- to less-invasive study or angiography. Otherwise, angiography is usually reserved for therapeutic planning and treatment.

Diagnosis and management of extensive vascular malformations of the lower limb: part II. Systemic repercussions [corrected], diagnosis, and treatment

At least nine types of vascular malformations with specific clinical and radiologic characteristics must be distinguished in the lower limbs: Klippel-Trénaunay syndrome, port-wine stain with or without hypertrophy, cutis marmorata telangiectatica congenita, macrocephaly-capillary malformation, Parkes Weber syndrome, Stewart-Bluefarb syndrome, venous malformation, glomuvenous malformation, and lymphatic malformation. Extensive vascular malformations are often more complex than they appear and require a multidisciplinary therapeutic approach. Vascular malformations may be associated with underlying disease or systemic anomalies. Part II of this two-part series on the diagnosis and management of extensive vascular malformations of the lower limb highlights the systemic repercussions [corrected] (bone, articular, visceral, and hematologic involvement), diagnosis, and treatment of these lesions.

Exsanguination by intent: controlled phlebotomy during resection of a giant vascular malformation in a 22-month-old child

Resection of large vascular malformations may require transection across the lesion, resulting in uncontrollable bleeding with the risk of exsanguination or massive transfusion-related complications such as hyperkalemic cardiac arrest. We present the anesthetic management of a 22-month-old child with a giant vascular malformation who required surgical intervention because of increasing pain and bleeding from the lesion. As a standard resection carried a high risk of mortality for the patient, a novel surgical approach was performed, consisting of gradual compression of the lesion, reducing its base to allow transection across the smallest possible area. This compression resulted in acute massive autotransfusion managed by therapeutic phlebotomy of more than twice the circulating blood volume of the patient, guided by CVP and blood pressure. Although subsequent resection was still associated with large blood loss, the hemodynamic course of the patient was stable, and both bleeding and massive transfusion occurred in a controlled fashion allowing safe and successful resection of the malformation.

The surgical management of 73 vascular malformations and preoperative predictive factors of major haemorrhage--a single centre experience

OBJECTIVES

In our series of patients with congenital vascular malformations (CVMs) we investigate the preoperative factors for predicting major haemorrhage at surgery and propose an algorithm for their surgical management.

DESIGN

This is a partly prospective case series of patients with severe symptoms/complications due to CVMs.

MATERIALS AND METHODS

Data were collected on 73 consecutive procedures in 41 patients with CVMs from 1992 to 2006 at a large university hospital and the association of following factors with blood loss during the procedure were investigated: type of procedure, possibility of proximal tourniquet use, lesion flow characteristics, previous history of major haemorrhage with CVM surgery, platelet counts and length of hospital stay.

RESULTS

Significantly higher blood loss was associated with debulking surgery (p=0.006) and with previous history of major haemorrhage during CVM surgery, (p=0.041). Blood loss was higher in lesions where proximal tourniquet application was not possible (p=0.093). High-flow lesions were not strongly associated with major blood loss (p=0.288). Major blood loss (>2l) occurred in 16 (20.8%) procedures performed on 11 (26.2%) patients, but this did not prolong hospital stay.

CONCLUSION

Surgery can potentially improve morbidity/mortality in patients with life/limb-threatening complications or severe symptoms due to CVMs, providing they are managed in multidisciplinary specialised centres.