Endovascular venous thrombolysis in children younger than 24 months

Interventional Treatment of Pediatric Venous Thromboembolic Disease

This review explores the clinical presentation of lower extremity DVT and pulmonary embolism (PE), treatment strategies, and outcomes for venous thromboembolism (VTE) in the pediatric population. Traditional therapy for pediatric VTE was anticoagulation alone with thrombolysis and surgery reserved only in life or limb-threatening cases. Catheter-directed thrombolysis (CDT), pharmacomechanical thrombectomy (PMT) and mechanical thrombectomy (MT) have emerged as effective and safe treatment options for VTE management. Although most data are from adult studies, early pediatric studies suggest that these interventional procedures can be effective in children. The significant clinical impact of post-thrombotic syndrome (PTS) is also discussed, as PTS can lead to lifelong physical symptoms and psychosocial damage.

Clinical characteristics and outcomes of combined thrombolysis and anticoagulation for pediatric and young adult lower extremity and inferior vena cava thrombosis

Effective treatment for acute, extensive, symptomatic lower extremity (LE) thrombosis involves thrombolysis in addition to anticoagulation. There is limited available data on the outcomes and safety of thrombolysis to help guide its use in pediatrics and young adults. A retrospective study of children and young adults (<21 years of age) that received catheter directed thrombolysis (CDT) for LE and inferior vena cava (IVC) thrombosis was performed over a 5-year span at a pediatric tertiary care center. A total of 29 patients were identified for inclusion in the study, 76% (n = 22) received overnight CDT while 24% (n = 7) received tissue plasminogen activator as a bolus dose during a single interventional procedure. The median age of the cohort was 15.8 years (range 0-19.1). All patients were treated with a course of therapeutic anticoagulation. The thromboses represented were extensive, with 93% (n = 27) being occlusive and affecting multiple venous segments. Thrombus resolution occurred in 35% (n = 10) of patients. Rivaroxaban use (p < 0.01) during the course of anticoagulation and estrogen-containing hormonal therapy (p = 0.01) use prior to diagnosis were associated with thrombus resolution, while Hispanic ethnicity (p = 0.06) had a trend toward thrombus persistence. There were one major and 3 minor bleeding events that occurred as complications of thrombolysis and no treatment related deaths. This study provides baseline information that can be used to help guide clinicians treating similar patients and suggests the need to develop an improved, uniform treatment approach for superior resolution rates.

Thrombolysis in Children: A Case Report and Review of the Literature

Thromboembolism (TE), including venous thromboembolism (VTE), arterial TE, arterial ischemic stroke (AIS), and myocardial infarction (MI), is considered a relatively rare complication in the pediatric population. Yet, the incidence is rising, especially in hospitalized children. The vast majority of pediatric TE occurs in the setting of at least one identifiable risk factor. Most recently, acute COVID-19 and multisystem inflammatory syndrome in children (MIS-C) have demonstrated an increased risk for TE development. The mainstay for the management pediatric TE has been anticoagulation. Thrombolytic therapy is employed more frequently in adult patients with ample data supporting its use. The data for thrombolysis in pediatric patients is more limited, but the utilization of this therapy is becoming more commonplace in tertiary care pediatric hospitals. Understanding the data on thrombolysis use in pediatric TE and the involved risks is critical before initiating one of these therapies. In this paper, we present the case of an adolescent male with acute fulminant myocarditis and cardiogenic shock likely secondary to MIS-C requiring extracorporeal life support (ECLS) who developed an extensive thrombus burden that was successfully resolved utilizing four simultaneous catheter-directed thrombolysis (CDT) infusions in addition to a review of the literature on the use of thrombolytic therapy in children.

Interventional Therapy for Upper Extremity Deep Vein Thrombosis

Approximately 10% of all deep vein thromboses occur in the upper extremity, and that number is increasing due to the use of peripherally inserted central catheters. Sequelae of upper extremity deep vein thrombosis (UEDVT) are similar to those for lower extremity deep vein thrombosis (LEDVT) and include postthrombotic syndrome and pulmonary embolism. In addition to systemic anticoagulation, there are multiple interventional treatment options for UEDVT with the potential to reduce the incidence of these sequelae. To date, there have been no randomized trials to define the optimal management strategy for patients presenting with UEDVT, so many conclusions are drawn from smaller, single-center studies or from LEDVT research. In this article, the authors describe the evidence for the currently available treatment options and an approach to a patient with acute UEDVT.

Pediatric Thrombolysis: A Practical Approach

The incidence of pediatric venous thromboembolic disease is increasing in hospitalized children. While the mainstay of treatment of pediatric thrombosis is anticoagulation, reports on the use of systemic thrombolysis, endovascular thrombolysis, and mechanical thrombectomy have steadily been increasing in this population. Thrombolysis is indicated in the setting of life- or limb-threatening thrombosis. Thrombolysis can rapidly improve venous patency thereby quickly ameliorating acute signs and symptoms of thrombosis and may improve long-term outcomes such as postthrombotic syndrome. Systemic and endovascular thrombolysis can result in an increase in minor bleeding in pediatric patients, compared with anticoagulation alone, and major bleeding events are a continued concern. Also, endovascular treatment is invasive and requires technical expertise by interventional radiology or vascular surgery, and such expertise may be lacking at many pediatric centers. The goal of this mini-review is to summarize the current state of knowledge of thrombolysis/thrombectomy techniques, benefits, and challenges in pediatric thrombosis.

Endovascular thrombolysis to salvage central venous access in children with catheter-associated upper extremity deep vein thrombosis: technique and initial results

Nine patients (average age 8.3 years, range 20 days to 17 years; average weight 31 kg, range 2.7-79 kg) with catheter-associated UE-DVT underwent upper extremity venous thrombolysis with the goal of access salvage. Catheter directed therapy with alteplase (tPA), balloon angioplasty, and mechanical thrombectomy was used in all cases. The mean total dose of TPA was 15 mg (range 1-40 mg). Venous access was ultimately preserved in all patients. No stents or superior vena cava filters were used. There was one episode of symptomatic clinically suspected pulmonary embolism managed by systemic tPA and heparin without long term sequaele. Mean imaging and clinical follow-up was 351 ± 208 and 613 ± 498 days respectively. Endovenous thrombolysis for catheter-associated upper-extremity DVT in children may be safe and effective and could be considered particularly in patients in whom long-term venous access is needed.

Tissue Plasminogen Activator Use in Children: Bleeding Complications and Thrombus Resolution

OBJECTIVE

To review our institutional experience with tissue plasminogen activator (tPA) to determine outcomes related to bleeding complications and thrombus resolution.

STUDY DESIGN

We performed a retrospective review of all patients who received systemic tPA for thrombolysis. Data points included location of thrombus, initial and maximum tPA dose, and duration of tPA. The primary endpoint was bleeding complication.

RESULTS

Between 2005 and 2014, 46 patients received systemic tPA for thrombolysis: 17 (37%) were patients with a primary cardiac diagnosis, there were 17 (37%) hematology/oncology patients, and 12 (26%) patients with noncardiac, nonhematology/oncology diagnoses. The indication for tPA was central venous thrombus (n = 23), pulmonary artery thrombus (n = 9), and cardiac or aortic thrombus (n = 14). Bleeding complications occurred in 15 patients (33%). Median initial tPA dose in the bleeding complication group was 0.10 mg/kg/h vs 0.03 mg/kg/h in the group without bleeding complication group (P = .01). Cardiac patients experienced more bleeding complications (P = .01). Multivariate analysis indicated that dose of tPA (P = .01) and diagnostic category (P < .01) were associated with bleeding complication. Complete thrombus resolution occurred in 21 patients, partial in 10 patients, and no resolution in 15 patients. Complete resolution of thrombus was not associated with diagnosis, thrombus location, tPA dose, or duration.

CONCLUSIONS

Cardiac patients appear to be at highest risk of bleeding complication; bleeding complications were associated with higher doses of tPA, and cardiac patients were the cohort who received the highest doses of tPA. Higher tPA doses are associated with increased risk of bleeding complication but are not associated with successful thrombus resolution.

Management of venous thrombosis in the pediatric patient

The incidence of venous thromboembolism in children has increased significantly over the past decade. The evaluation and management of the child with venous thromboembolism, while based on the adult experience, has its own particularities dictated by the differences in the hemostatic system of the newborn and child. The current review addresses the evaluation of pediatric patient with thrombosis as well as the established and emerging treatment interventions.

Pharmacomechanical thrombectomy and catheter-directed thrombolysis of acute lower extremity deep venous thrombosis in a 9-year-old boy with inferior vena cava atresia

Lower extremity deep venous thrombosis (DVT) is uncommon in the pediatric population, but it can be associated with severe symptoms and potential long-term morbidity secondary to post-thrombotic syndrome. Inferior vena cava (IVC) atresia can predispose a patient to the development of extremity DVT. There is no clear consensus on optimal management of extensive extremity DVT in pediatric patients, especially in patients with IVC anomalies. We report a case of iliofemoral DVT in a 9-year-old boy with IVC atresia and presumed protein S deficiency that was treated successfully using pharmacomechanical thrombectomy and catheter-directed thrombolysis. He was maintained on long-term anticoagulation and remained symptom free at 6 months' follow-up.