Thrombosis in children with cardiac pathology: frequency of factor V Leiden and prothrombin G20210A mutations

Intracardiac thrombi in pediatrics: anticoagulation approach and treatment outcomes

Background

Intracardiac thrombi (ICT) are associated with significant morbidity and mortality. Anticoagulation is the first line of treatment and may be complemented by thrombectomy or thrombolysis. However, optimal anticoagulant duration remains ill-defined. High-risk features of ICT that may warrant long-term anticoagulation therapy have not been established.

Objectives

To describe anticoagulation duration and patterns of ICT resolution. To identify potential risk factors for persistent ICT despite anticoagulation.

Methods

A single-institution retrospective chart review identified patients diagnosed with ICT by echocardiogram between January 2014 and March 2022. Descriptive statistics and logistic regression were used.

Results

Fifty-one patients with ICT were identified. Median age at diagnosis was 9.2 years (IQR, 0.4-15.2). The most common underlying diagnoses were congenital heart disease (41%), infection (25%), and malignancy (24%). The majority of ICT were in the right atrium (n = 30). The median longest ICT dimension was 1.5 cm (range, 0.4-4.0). The median duration of anticoagulation was 4.3 months (IQR, 2.2-9.1). Among 48 patients who received anticoagulation as first-line treatment, 32 had partial or complete response with 3 to 6 months of anticoagulation, while remaining 16 patients had no response to anticoagulation. Patients with a central venous line had a delayed resolution of ICT [hazards ratio = 0.45 (95% CI, 0.22-0.93)].

Conclusion

Our study demonstrates the wide variability in duration of anticoagulation for children with ICT. Majority of the individuals benefit from 3-to-6 month treatment; however, individuals with a central venous line may benefit from a longer course of anticoagulation. Further large-scale studies are recommended to validate our findings.

Intracardiac thrombosis after congenital heart disease surgeries in neonates: a report of two cases

BACKGROUND

Intracardiac thrombosis (ICT) is a rare complication after the cardiopulmonary surgery for interrupted aortic arch (IAA) or total anomalous pulmonary venous connection (TAPVC) without previous records. There are still no general guidelines regarding as the mechanism or management of postoperative ICT in neonates and younger infants.

CASE PRESENTATION

We reported the conservative and surgical therapies in two neonates with intra-ventricular and intra-atrial thrombosis after the anatomical repair for IAA and TAPVC, respectively. There were no risk factors for ICT in both patients, except for the use of blood product and prothrombin complex concentrate. The surgery was indicated after TAPVC correction due to the worsening respiratory status and rapidly decreased mixed venous saturation. Anticoagulation combined with antiplatelet therapies was adopted in another patient. These two were both finally recovered, and three-month, six-month, and one-year follow-up echocardiography revealed no abnormality.

CONCLUSIONS

ICT is uncommon in pediatric population after the surgery for congenital heart disease. Single ventricle palliation, heart transplantation, longer central line use, post-extracorporeal membrane oxygenation, and massive blood product use are major risk factors for postcardiotomy thrombosis. The causes of postoperative ICT are multifactorial, and the immaturity of thrombolytic and fibrinolytic system in neonates may serve as a prothrombotic factor. However, no consensus reached regarding as the therapies for postoperative ICT, and the large-scale prospective cohort study or randomized clinical trial is needed.

Assessment of clinical characteristics and treatment outcomes of pediatric patients with intracardiac thrombosis: a single-center experience

The prevalence of intracardiac thrombus (ICT) is gradually increasing, though it is rare among children. Data related to the occurrence of ICT among children are limited, and treatment recommendations have been made utilizing adult guidelines. The primary objective of this study is to determine associated factors, management, and outcomes of intracardiac thrombosis in children. Between January 2013 and January 2020, patients diagnosed with ICT at the Pediatric Hematology-Oncology and Pediatric Cardiology departments in our hospital were included in the study. Demographic characteristics, clinical and laboratory findings, treatment protocols, and outcomes were analyzed retrospectively. The median age at diagnosis was 10.5 months (2 days to 14.5 years), and the median follow-up period was 6.5 months (1 month to 3.1 years). The most common primary diagnoses of the patients, in order of frequency, were heart disease (n: 8), metabolic disease (n: 3), prematurity and RDS (n: 3), burns (n: 2), pneumonia (n: 2), and asphyxia (n: 2). CVC was present in 19/23 of the patients. The reasons for CVC insertion were the need for plasmapheresis in one patient with a diagnosis of HUS and the need for well tolerated vascular access because of long-term hospitalization in others. LMWH was administered to all patients as first-line therapy. Complete response was achieved in 19 (79%) of 24 patients and 4 patients (16.6%) were unresponsive to medical treatment. It was found out that the thrombus location, type, sepsis, and hemoculture positivity, as well as the presence of CVC, had no impact on treatment response (chi-square P = 0.16, 0.12, 0.3, 0.49, 0.56). Moreover, no correlation was determined between thrombus size and treatment response (Mann Whitney U test P = 0.47). The mortality rate was determined to be 12.5% (3/24). Spontaneous occurrence of ICT is rare in childhood, without any underlying primary disease or associated factor. The presence of CVC, sepsis, and heart disease are factors associated with ICT. The success rate is increased with medical treatment. There was no significant difference in treatment response between the newborn and 1 month to 18-year-old patient group. It has been demonstrated that thrombus size, type, localization; sepsis, and hemoculture positivity had no impact on the treatment response.

Single Ventricle Physiology Patients and Coagulation Abnormalities: Is There a Relationship With Hemodynamic Data and Postoperative Course? A Pilot Study

This study evaluates coagulation profiles of single ventricle (SV) patients in relationship to liver function, hemodynamic variables and outcome. Twenty-six children with SV anatomy were included. Advanced coagulation profiles, invasive preoperative hemodynamic parameters and clinical course were retrospectively analyzed. Median (interquartile range) age and weight at the time of blood sampling was 25.5 (31) months and 10.5 (6.9) kg. Sixteen patients (16/26; 62%) showed decreased antithrombin and/or protein C (PC) and/or free protein S (PS) function and/or free PS antigen. Two patients showed abnormal activated PC resistance ratio due to heterozygous factor V Leiden mutation and 1 heterozygous prothrombin G20210A mutation. Group comparison (abnormal coagulation profile [group 1; n = 16] versus normal coagulation profile [group 2; n = 10]) showed longer postoperative hospitalization time (p = .04), longer postoperative catecholamine support (p = .01), a higher incidence of thromboembolic events (p = .04), and chylothoraxes (p = .007) in group 1. In 5 (31%) of 16 group 1 patients, thromboembolic complications occurred: cerebral stroke (n = 1), intestinal ischemia (n = 2), thrombus formation in inferior caval vein (n = 1), and pulmonary vein (n = 1). Abnormalities in coagulation parameters are common in SV patients. Coagulation abnormalities constitute a preoperative risk factor and affect postoperative course.

Venous thromboembolism in chronic pediatric heart disease is associated with substantial health care burden and expenditures

ABSTRACT

Background: Venous thromboembolism (VTE) is a complication in children with chronic pediatric heart disease (CPHD). The influence of acute VTE risk factors and the health care burden associated with VTE in CPHD is unknown.Methods: Children <18 years of age with a CPHD diagnostic code were identified from the 2003-2013 MarketScan Commercial Databases. VTE diagnoses were identified either concomitantly with initial CPHD diagnoses or during a 6-month follow-up. The associations between demographic and clinical characteristics and VTE among children with CPHD, stratified by recent cardiac surgery, were assessed by multivariable logistic regression models. Estimates of health care utilization were compared using Wilcoxon rank-sum tests.Results: VTE events occurred in 957 of 120 884 children with CPHD (0.8%). In-hospital mortality was significantly higher in children with VTE. Single-ventricle physiology had the highest VTE rate (2.3%). All comorbid conditions were significantly associated with VTE, but the prevalence was highest in children with recent cardiac (11.1%) or noncardiac surgery (7.8%). The magnitude of association between noncardiac comorbidities and acquired acute cardiovascular conditions and VTE were larger for children without a recent cardiac surgery. Children with VTE had significantly higher health care utilization.Conclusions: VTE in CPHD is associated with significantly increased health care resource utilization and in-hospital mortality. All of the comorbid conditions examined were significantly associated with VTE, but a recent surgical procedure, especially cardiac surgery, conferred the highest VTE risk. Although confounding inherently limits observational studies, these findings provide practical information about the health care costs among patients with CPHD and VTE.

Tetralogy of Fallot: Stroke in a Young Patient

Tetralogy of Fallot (TOF) is a congenital birth defect of the heart which actually comprises four individual flaws. It causes poor flow of oxygenated blood to the organs and leads to cyanosis (blue-tinted skin, because of inadequate oxygenation). It can be recognized at birth or in adulthood. But sometimes, cases may go unnoticed, and the patient might present with some rare complications. In this case, the patient presented with an embolic infarct of the brain at the age of 25 with an undiagnosed tetralogy of Fallot.

Risk Factors, Prophylaxis, and Treatment of Venous Thromboembolism in Congenital Heart Disease Patients

Congenital heart disease (CHD) is a common condition in the pediatric population, affecting up to 1% of all live births (i.e., around 40,000 newborns/year in the United States). Although CHD does have a wide range of severity, by the age of 5 years approximately 80% of patients will require at least one surgical intervention to achieve a complete/palliative cardiac repair. Today, in light of their much-improved surgical survival, the care of these patients focuses on morbidity prevention and/or treatment. One such morbidity has been the increased frequency of thrombotic occlusions [e.g., cardioembolic arterial ischemic strokes; arterial, cardiac, and/or newly created shunt thrombosis; venous thromboembolism (VTE)]. Patients with CHD are at high risk of developing thrombosis due to the disruption of blood flow, CHD-related coagulopathy, inflammation, and/or platelet activation secondary to extracorporeal circulation support required during open-heart surgery or as a bridge to recovery, which can increase thrombus formation. In this article, we will discuss how the coagulation system is altered in patients with CHD in regard to the patient's anatomy, procedures they undergo to correct their congenital heart defect, and other risk factors that may increase their thrombotic risk, focusing on VTE. We will also discuss the most recently published reports pertaining to guidelines on prophylaxis and treatment of VTE in this population. Finally, we will briefly address the long-term VTE outcomes for patients with CHD.

Role of thrombophilia factors in acute systemic-pulmonary shunt obstruction

BACKGROUND

Systemic-pulmonary shunts are widely used in initial palliation in cyanotic congenital heart disease. The incidence and the relationship between acute shunt obstruction and thrombophilia are not precisely defined. The aim of this study was to determine the frequency of shunt obstruction in the early postoperative period, and to define the frequency and presence of thrombophilia factors in patients treated for acute shunt thrombosis.

METHODS

Between October 2010 and October 2012, 77 patients who had systemic-pulmonary shunt operation were included in this prospective study. Patients who developed shunt obstruction were examined in terms of inherited and acquired thrombophilia factors.

RESULTS

Median patient age was 61 days and median weight was 4.3 kg. Thirty-three patients were neonates. Diameter of the Gore-Tex grafts used for the shunt ranged from 3 mm to 5 mm. Acute shunt occlusion rate was 10% (8/77), and all of these occurred in the first 24 h. Thrombophilia was found in three of eight patients who underwent intervention (surgical and/or transcatheter) due to shunt thrombosis (presence of anti-phospholipid antibodies, n = 1; protein C deficiency, n = 1; and factor V Leiden mutation, n = 1) and only one patient died.

CONCLUSIONS

Acute shunt obstruction developed in 10% of patients who underwent systemic-pulmonary shunt, and emergency surgery or transcatheter intervention can be life saving in this context. Acute shunt obstruction can occur due to mechanical and hemodynamic problems, but clinicians should also consider and evaluate thrombophilia factors.

Development and Implementation Results of a Venous Thromboembolism Prophylaxis Guideline in a Tertiary Care Pediatric Hospital

OBJECTIVES

Incidence of pediatric venous thromboembolism (VTE) is increasing due to increased survival of children with chronic diseases and use of interventions (eg, central venous lines), with VTE risk. Our objective was to create VTE prophylaxis guidelines with targeted identification of children at high risk to support appropriate mechanical and pharmacologic prophylaxis and integrate into the electronic medical record (EMR) as a hospital-wide quality improvement project.

METHODS

Patients aged 12 to 17 years were included. We evaluated institutional data regarding VTE incidence and risk factors. We evaluated literature for populations at high risk for VTE. Guidelines were formulated, and an EMR tool to assess risk and support the guidelines was created and implemented.

RESULTS

The EMR tool was used to screen 48% of qualified admissions for the first month and 81% in the final study month. On average, 69.1% of qualified admissions were screened monthly during the first 18 months of the program. No adverse events were reported due to pharmacologic prophylaxis.

CONCLUSIONS

Many risk factors are common between children and adults and certain pediatric populations warrant prophylactic consideration. Pediatric VTE prophylaxis guidelines can be successfully implemented into the EMR to identify high-risk populations. Future studies should assess the long-term impact of implementation.

Intracardiac thrombus in children: the fine equilibrium between the risk and the benefit

The medical records of 16 patients diagnosed as intracardiac thrombus were searched. The size, location and outcome of thrombus together with demographic data of patients were assessed. The median age of the patients was 2.2 years. Six patients were newborn and two patients were infant. The median size of thrombus was 9 mm. The localization was right atrium in seven, right ventricle in five, left ventricle in one, pulmonary artery in one, and superior vena cava in two patients. There was prematurity in five, ciyanotic congenital heart disease in one, blood culture positivity in three, malignancy in four, nephrotic syndrome in one, indwelling catheters in 10, and acquired or genetic thrombophilia in six patients as risk factors. In the treatment, the first choice was tissue plasminogen activator in two patients, heparin infusion in one patient and low molecular weight heparin in remaining 12 patients. In nine patients, therapy included parenteral antimicrobials together with anticoagulants. The result was complete resolution in 15 patients and in one patient thrombus was surgically removed. The median time was 16 (2-70) days for 50% resolution and 26 (3-93) days for complete resolution. There was a statistically significant (P = .027 and r = 0.5) correlation between the size and the complete resolution time. There was no anticoagulant therapy related major complication. In patients with intracardiac thrombus, selection of anticoagulant therapy may decrease the risk of complications. Surgery is rarely required and thrombolytics are not usually necessary for resolution of thrombus.

Thrombolysis With Recombinant Tissue Plasminogen Activator in 7 Children

The information about the thromboembolic events, the optimal treatment choice, the dose, and duration of antithrombotic therapy in children are limited. More clinical data are required. Recombinant tissue plasminogen activator (r-tPA) is increasingly used in pediatric thrombosis. We retrospectively analyzed the clinical course of 7 children (9.3 ± 2.1 years; 34 days to 16 years) with arterial thrombosis (n = 1) and intracardiac thrombosis (n = 6). The children were treated with r-tPA. The dose ranged between 0.2 and 0.4 mg/kg per h infused for 3 to 4 hours. This dose was repeated between 2 to 7 times till the thrombolysis was achieved. Treatment side effects were closely monitored. Complete clot lysis was achieved in all cases. None of them had severe bleeding except mild recurrent epistaxis occurring in 2 cases. In conclusion, r-tPA is an effective and safe therapy under close hemostatic control in children.

Incidence and risk factors for venous thromboembolism in critically ill children with cardiac disease

Cardiac disease is a risk factor for venous thromboembolism (VTE) in children. In this study, we investigated the incidence and risk factors of VTE in critically ill children with cardiac disease, who were prospectively followed-up for VTE after admission to a tertiary care pediatric intensive care unit (PICU). Risk factors were compared between VTE cases and (1) patients in the cohort who did not develop VTE and (2) the next three cardiac patients sequentially admitted to the PICU (case control). Forty-one cases of VTE were identified from 1070 admissions (3.8%). Thirty-seven percent of VTE cases were central venous catheter (CVC)-associated, and 56% of cases were intracardiac. Sixty-six percent of patients were receiving anticoagulation at the time of VTE diagnosis. Increased VTE incidence was associated with unscheduled PICU admission, age <6 months, extracorporeal membrane oxygenation, increased number of CVCs, increased number of CVC days, higher risk of mortality score, and longer PICU stay. Using logistic regression, VTE was associated with single-ventricle physiology (odds ratio [OR] 11.2, 95% CI 3.0-41.9), widened arterial-to-somatic oxygen saturation gradient (SpO(2)-rSO(2) >30) (OR 4.3, 95% CI 1.1-16), and more CVC days (OR 1.1, 95% CI 1.04-1.13). Risk factors for VTE in critically ill children with cardiac disease include younger age, single-ventricle cardiac lesions, increased illness severity, unscheduled PICU admission, and complicated hospital course.

Thrombophilia, left ventricular dysfunction and intracardiac thrombi in children

Background and Objectives

Reports on the incidence of intracardiac thrombi (ICT) have increased over the last few decades, but ICT are still relatively rare among children. Left ventricular systolic dysfunction and dilatation may contribute to the formation of ICT, especially when a hypercoagulable state exists. The aim of this study was to describe the incidence of ICT in children suffering from cardiac failure with left ventricular dysfunction and to identify risk factors on admission for developing ICT.

Subjects and Methods

We conducted a retrospective chart review of children up to 18 years of age admitted to the Pediatric Intensive Care Unit due to cardiac failure with left ventricular dysfunction between January 1, 2003 and December 31, 2008.

Results

Twenty-one patients were admitted with clinical signs of cardiac failure and echocardiographic findings compatible with dilated cardiomyopathy or acute myocarditis. Dilated cardiomyopathy was diagnosed in 11 patients (52%). Adenoviruses and enteroviruses were suspected to be the cause of acute myocarditis in 5 cases. The personal or family history of hypercoagulable states were obtained from 19 out of 21 patients (90%). Among patients with a hypercoagulable state, 3 out of 7 developed ICT compared with none out of 12 among patients without hypercoagulability (p=0.043). Two of these 3 patients experienced an embolic event.

Conclusion

Cardiac failure with left ventricular dysfunction may predispose the patient to ICT and increase the risk of thromboembolism, especially when an underlying hypercoagulable state exists. The hypercoagulable state must be carefully evaluated on admission in these patients.

Atrioventricular thrombus in a 14-year-old patient: a case report

Right atrioventricular thrombus was diagnosed by echocardiography in a 14-year-old boy. Thrombus was reached through the right ventricle to the pulmonary artery and it was caused to tricuspit valve insufficiency. Surgical thrombectomy was performed and, he was treated with oral anticoagulation in postoperative period.

Diffuse Cerebral Infarct Associated With Factor V Leiden and Prothrombin 20210A Mutations in a Patient With Tetralogy of Fallot

A 2-year-old girl with tetralogy of Fallot presented with diffuse cranial infarct after cardiac angiography. Heterozygosity for factor V Leiden and prothrombin 20210A mutations were detected. The authors suggest that if thrombosis develops in patients with congenital heart disease, genetic risk factors should be evaluated.

Intracardiac thrombi in pediatric patients: presentation profiles and clinical outcomes

We document the presentation profiles, treatment strategies, and clinical outcomes in a relatively large cohort of pediatric patients with intracardiac thrombi (ICT). We performed a retrospective review of patients diagnosed with ICT by echocardiography at a tertiary pediatric hospital during a 10-year period. These patients received medical therapy or thrombectomy. We provided echocardiographic descriptions of the ICT-size, chamber location, and mobility/morphology. The outcome measures were ICT (persistence, resolution, or embolization), effectiveness of therapy, and patient morbidity and mortality. There were 40 ICT diagnosed in 31 patients (22 males and 9 females). Mean age at diagnosis was 8.8 years (range, 15 days to 18 years). Overall mortality was 12/31 patients (39%); only one death was attributed to ICT embolization. Embolic events occurred in 4/31 patients (13%). The most common initial therapies included heparin infusion (n = 15), warfarin (n = 7), and aspirin (n = 7). The ICT resolved with medical therapy alone in 19/30 patients (63%). One patient required surgical thrombectomy. The cohort was divided into group 1 (dilated cardiomyopathy), group 2 (status post Fontan operation), and group 3 (other diagnoses). In group 1 (n = 11), there were 8 deaths. Embolization occurred in 2/5 large ICT, resulting in cerebral infarction and death (n = 1) and renal infarction (n = 1). The most common ICT location was the left ventricle (n = 10). Severe ventricular systolic dysfunction was present in 10/11 patients (91%). In group 2 (n = 9), there was 1 death. Embolization occurred in 1/7 large ICT, resulting in seizures and temporary paresis. All ICT were located in the Fontan pathway. Severe ventricular systolic dysfunction was present in 2/9 patients (22%). In group 3 (n = 11), there were 3 deaths. Embolization occurred in 1/9 small ICT, resulting in coronary emboli. ICT are most commonly diagnosed in pediatric patients with dilated cardiomyopathy or patients status post Fontan operation. The majority of ICT resolve with medical therapy. Larger ICT tend to embolize more frequently, and the morbidity secondary to embolization is significant. Rarely is mortality due to ICT embolization. The prognosis is poor for patients with left ventricular ICT or ICT in the presence of ventricular systolic dysfunction.

Stroke following Glenn anastomosis in a child with inherited thrombophilia

The optimal anticoagulation following Fontan operation and its modifications remain controversial and it is even less well defined as regards patients with inherited thrombophilia. We present a case of a child with bidirectional Glenn anastomosis for double inlet left ventricle that suffered a stroke despite aspirin prophylaxis; the patient was combined homozygous for prothrombin G20210A mutation and for methylenetetrahydrofolate reductase C677T mutation as well. The family history was positive for fetal loss and premature cardiovascular disease. Large-scale studies are needed to evaluate whether carriers of thrombophilia mutations need more intense thromboprophylaxis.

Association of prothrombin gene mutation with sepsis in a preterm with multiple intracardiac thrombi

We report for the first time, a premature infant with multiple intracardiac thrombi and sepsis, who was heterozygous for the G20210A prothrombin gene variant. Anticoagulant treatment with low molecular weight heparin resulted in the complete disappearance of the thrombi. It may be suggested that prothrombin gene variant associated with sepsis, respiratory distress syndrome, and perinatal asphyxia, as well as other thrombophilic disorders, could be a risk factor for the development of neonatal thrombus.

Factor V Leiden and its effect on children with cardiac pathology

Factor V Leiden thrombophilia, formed by a genetic mutation, slows the body's anticoagulation response to clot formation. First described in 1994, factor V Leiden mutation has been identified as a contributing risk factor for venous thromboembolism. Although venous thromboembolism is considered rare in the pediatric population, Factor V Leiden has implications for certain at-risk pediatric patients.

Analysis of some clinical and laboratory aspects of adolescent patients with thrombosis

A total of 360 pediatric patients aged 1 month to 18 years were diagnosed as having thrombosis between January 1998 and April 2003. Of these patients, those aged 11-18 years (n=131) were regarded as adolescents and the rest as children. The proportion of adolescents in the whole group excluding the neonates was 36%. The peak age of diagnosis in adolescents was 11-14 years, comprising 58% of all thrombotic events in adolescents. In 73% of the adolescents, there was at least one risk factor. The four most common underlying disorders were infection, malignancy, connective tissue and cardiac disorders, in decreasing order of frequency. In children, on the other hand, infection was followed by congenital heart disease, malignancy and liver disease. Three common types of thrombosis in adolescents were deep venous thrombosis, cerebro-vascular events and portal venous thrombosis, while cerebro-vascular events were the most common in children. The frequency of factor V G1691A mutation in the adolescents (22.1%) was significantly higher than that found in a group of healthy controls (7.4%) and this mutation was associated with a 3.6-fold increase in the risk of developing thrombosis (95% confidence interval, 1.4-9.0). The carrier frequency of prothrombin G20210A mutation (3.1%) in adolescents did not differ significantly from that of the healthy population (2.3%) and no association was observed between this mutation and a risk of developing thrombosis in this group (odds ratio, 1.3; 95% confidence interval, 0.2-7.5). The rate of recurrent thrombosis was 6%.