Anticoagulation in Children With Mechanical Valve Prostheses

doi:10.1016/S0003-4975(97)00453-0

The Annals of Thoracic Surgery

Volume 64, Issue 1, July 1997, Pages 30-36

Presented at the Forty-third Annual Meeting of the Southern Thoracic Surgical Association, Cancun, Mexico, Nov 7–9, 1996.

https://doi.org/10.1016/S0003-4975(97)00453-0 Get rights and content

Abstract

Background. Clotting complications in patients with mechanical valve prostheses can be prevented with either warfarin sodium (Coumadin; DuPont, Wilmington, DE) or antiplatelet agents. In children, it is not known whether one treatment regimen is more effective or safe than the other.

Methods. We prospectively followed up 64 children and young adults (aged 18 years or younger at implantation) with a mechanical valve on the left side of the heart, from October 1986 through October 1996. Forty-eight patients were treated with Coumadin and 16 with aspirin and dipyridamole. The two groups were similar in age, sex, valve location and size, mean length of follow-up, and operative indication. There has been a total follow-up of 272 patient-years on Coumadin and 116 patient-years on aspirin and dipyridamole.

Results. There was no difference between the two groups in survival or freedom from thromboembolism. Bleeding occurred more often in the patients taking Coumadin, but this difference was not statistically significant. Analysis of the literature showed thromboembolism and bleeding rates to be similar in the patients receiving Coumadin and those receiving antiplatelet agents.

Conclusions. Coumadin and the combination of aspirin plus dipyridamole provided similar protection against complications in this group of children and young adults with left-sided St. Jude (St. Paul, MN) mechanical valves. The choice between the two regimens may depend on other factors, such as patient preference and convenience.

Section snippets

Material and Methods

This study includes the 64 patients, aged 18 years or younger, who survived the implantation of a mechanical prosthetic valve in the aortic or mitral position. Three patients who underwent replacement of a tricuspid valve functioning as the systemic atrioventricular valve (2 after atrial repair for transposition of the great arteries and 1 with congenitally corrected transposition) were included. No patient was excluded from the study for any reason other than age at the time of operation. All

Results

There was no significant difference between the patients who received Coumadin and those who received aspirin and dipyridamole in age, sex, valve location, valve size, mean length of follow-up, or operative indication (see Table 1, Table 2). There was a total follow-up of 272 patient-years on Coumadin and 116 patient-years on aspirin and dipyridamole.

Comment

Coumadin and the combination of aspirin and dipyridamole were equally effective in this group of patients with mechanical valve prostheses. Mortality and thromboembolism rates were similar in the two groups (see Fig. 1, Fig. 2; Table 3). Bleeding complications occurred more frequently in the patients who received Coumadin (see Fig. 3; Table 3). However, this difference did not achieve statistical significance. Thus, neither anticoagulation regimen provided significant benefit over the other in

References (20)

LH Edmunds
Thrombotic and bleeding complications of prosthetic heart valves
Ann Thorac Surg
(1987)
ED Verrier et al.
Aspirin anticoagulation in children with mechanical aortic valves
J Thorac Cardiovasc Surg
(1986)
MN Ilbawi et al.
Experience with St. Jude Medical valve prosthesis in children
J Thorac Cardiovasc Surg
(1987)
Y Harada et al.
Ten-year follow-up after valve replacement with the St. Jude Medical prosthesis in children
J Thorac Cardiovasc Surg
(1990)
LM Bradley et al.
Anticoagulation therapy in children with mechanical prosthetic cardiac valves
Am J Cardiol
(1985)
A Milano et al.
Late results after left-sided cardiac valve replacement in children
J Thorac Cardiovasc Surg
(1986)
LB McGrath et al.
Thromboembolic and other events following valve replacement in a pediatric population treated with antiplatelet agents
Ann Thorac Surg
(1987)
MS Schaffer et al.
The St. Jude Medical cardiac valve in infants and children: role of anticoagulant therapy
J Am Coll Cardiol
(1987)
S Stewart et al.
The long-term risk of warfarin sodium therapy and the incidence of thromboembolism in children after prosthetic cardiac valve replacement
J Thorac Cardiovasc Surg
(1987)
CMG Duran et al.
Performance of 96 Carbomedics valve replacements in 75 patients less than twenty-one years of age
Ann Thorac Surg
(1994)

There are more references available in the full text version of this article.

Cited by (45)

Left ventricular outflow tract obstruction
2018, Critical Heart Disease in Infants and Children
Left ventricular outflow tract obstruction (LVOTO) is a complex congenital cardiac defect that interferes with the ejection of blood from the left ventricle into the ascending aorta. LVOTO is a heterogeneous defect in which the timing and mode of clinical presentation vary based on multiple factors, including the degree and levels of obstruction, associated hypoplasia of the left ventricle and mitral valve, and the presence of concomitant cardiac and extracardiac anomalies such as aortic arch obstruction, patent ductus arteriosus, and atrial or ventricular septal defect. Subsequently, the timing and type of intervention differ based on those factors, with the initial procedure ranging from an extreme of neonatal single-ventricle palliation to isolated adolescent aortic valve intervention. The classification of LVOTO is typically based on the level of obstruction and includes valvar, subvalvar, and supravalvar stenosis. Valvar stenosis is the most common type and constitutes approximately 65% to 75% of cases, whereas subvalvar and supravalvar stenosis constitute approximately 15% to 20% and 5% to 10% of cases, respectively.
Coagulation disorders in congenital heart disease
2018, Critical Heart Disease in Infants and Children
This chapter will review the process of normal coagulation in infants and children, examine the various tests of the clotting mechanism, review the alterations of hemostasis in congenital heart disease, consider the impact of cardiopulmonary bypass, extracorporeal membrane oxygenation (ECMO) and ventricular assist device (VAD) use on hemostasis, and develop strategies for the diagnosis and management of bleeding and thrombosis after pediatric cardiac surgery.
Clinical outcomes of mitral valve replacement with the 16-mm ATS advanced performance valve in neonates and infants
2015, Annals of Thoracic Surgery
Although mitral valve repair is the preferred treatment for mitral regurgitation in neonates and infants, mitral valve replacement (MVR) is sometimes necessary.
From 1999 through 2013, 18 patients younger than 1 year underwent MVR with the smallest (16 mm) commercially available mechanical valve. At surgery, mean age was 4.0 ± 1.8 months (range, 4 days to 7 months), and mean body weight was 5.3 ± 1.6 kg (range, 3.2 to 8.3 kg). Prosthetic valves were implanted in the supra-annular position in 17 of the 18 patients.
All patients were followed up, and the mean follow-up period was 4.5 ± 3.8 years (range, 0.2 to 14 years). The rates of overall survival and freedom from redo MVR at 10 years were 88.9% and 57.8%, respectively. The causes of redo MVR were pulmonary hypertension in patients with left ventricular outflow obstruction (n = 2), hemolysis (n = 1), and a stuck valve (n = 1). The estimated effective orifice area index (effective orifice area/body surface area) was significantly inversely correlated with peak transmitral pressure gradient (r = −0.784, p < 0.01). The rate of freedom from permanent pacemaker implantation at 10 years was 71.2%. Three of the 5 pacemaker implantation procedures were for postoperative sick sinus syndrome. Although intracranial hemorrhage developed in 3 infants, all neurologic sequelae resolved.
The implanted valves were durable, and no premature increase in transmitral pressure gradient was observed. Complications included injury of the sinus node artery and hemorrhage related to anticoagulation therapy.
Aortic valve replacement in children: Options and outcomes
2014, Journal of the Saudi Heart Association
Several disease pathologies such as congenital heart disease and rheumatic fever can affect the aortic valve (AV) in children frequently necessitating intervention. While percutaneous or surgical AV repair is recommended as initial management strategy in children with AV disease, AV replacement (AVR) might become necessary in children with significant valve destruction and after repair or intervention failure. AVR in children is associated with distinct clinical and technical problems owing to several anatomic, social and prosthesis-related issues.
In the current review, we list different AV substitutes, discuss their advantages and shortcomings, outline AVR results in children, and explore the divergence of outcomes in various age, anatomy and pathology subgroups; all in the aim to identify optimal AVR choice for each patient taking into consideration his unique anatomic and demographic characteristics.
Evolution of mitral valve replacement in children: A 40-year experience
2012, Annals of Thoracic Surgery
This report reviews our 40-year experience with pediatric mitral valve replacement (MVR) with respect to mortality, valve-related morbidity, and reoperation risk factors.
From 1970 to 2010, 97 patients have undergone a total of 136 MVRs. Median age was 8 years (2 weeks to 18 years), 41 patients (42%) were less than 5 years, and 16 were infants (17%). Etiology was congenital in 65 patients (67%), rheumatic in 27 (28%), and endocarditis in 5 (5%). Regurgitation was the predominant lesion in 67 patients (69%), stenosis in 23 (24%), and mixed in 7 (7%) patients. Mechanical valves (ball, n = 11; or bileaflet disc, n = 66) and xenografts (porcine, n = 14; bovine, n = 2) were used in 93 initial MVR patients. Since 2002, 5 children have undergone Ross MVR with a pulmonary autograft in 3 and an aortic homograft in 2.
Hospital mortality was 6% (6 of 97). There were 23 late deaths and 5 patients have required cardiac transplantation. Thirty-five year actuarial survival was 71%. Age less than 2 years, MVR prior to 1980, atrioventricular septal defect, univentricular heart, and additional left side obstructions were significant predictors of death. Mean follow-up was 12.8 ± 10.1 years (range, 2 months to 38 years). Seventeen patients with mechanical valves experienced systemic emboli in 9 (10%), valve thrombosis in 5 (6%), and bleeding requiring transfusion in 3 (3%) patients. Thirty-two patients required reoperations (35%) from 3 months to 14 years (mean, 6.5 ± 4.4 years) after initial MVR. Actuarial freedom from reoperation at 35 years was 63%. Variables associated with mitral re-replacement were younger age, small weight, valve diameter less than 23 mm, MVR prior to 1980, and type of implanted valves (xenograft, single-leaflet disk, ball-caged, or human valves).
Pediatric MVR can be performed with low initial mortality but should be reserved for medical and reconstruction failure because reoperation, valve-related complications, and late mortality are high. Bileaflet prostheses larger than 23 mm have the lowest reoperation risk. Ross MVR may offer select patients a durable tissue valve without lifelong anticoagulation and its associated complications.
Antithrombotic therapy in neonates and children: Antithrombotic therapy and prevention of thrombosis, 9th ed: American college of chest physicians evidence-based clinical practice guidelines
2012, Chest
Citation Excerpt :
Bleeding, when reported, is extremely rare.203,594,598–603 When VKAs are prescribed, the incidence of TE is reduced, but there is an increased bleeding incidence.203,590,594,599,600,602–613 A series of 32 children routinely treated with phenprocoumon collected over a 22-year period reported a 10-year freedom of 89.1% (1.2%/patient-year) from any anticoagulation-related adverse event.614
Neonates and children differ from adults in physiology, pharmacologic responses to drugs, epidemiology, and long-term consequences of thrombosis. This guideline addresses optimal strategies for the management of thrombosis in neonates and children.
The methods of this guideline follow those described in the Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines.
We suggest that where possible, pediatric hematologists with experience in thromboembolism manage pediatric patients with thromboembolism (Grade 2C). When this is not possible, we suggest a combination of a neonatologist/pediatrician and adult hematologist supported by consultation with an experienced pediatric hematologist (Grade 2C). We suggest that therapeutic unfractionated heparin in children is titrated to achieve a target anti-Xa range of 0.35 to 0.7 units/mL or an activated partial thromboplastin time range that correlates to this anti-Xa range or to a protamine titration range of 0.2 to 0.4 units/mL (Grade 2C). For neonates and children receiving either daily or bid therapeutic low-molecular-weight heparin, we suggest that the drug be monitored to a target range of 0.5 to 1.0 units/mL in a sample taken 4 to 6 h after subcutaneous injection or, alternatively, 0.5 to 0.8 units/mL in a sample taken 2 to 6 h after subcutaneous injection (Grade 2C).
The evidence supporting most recommendations for antithrombotic therapy in neonates and children remains weak. Studies addressing appropriate drug target ranges and monitoring requirements are urgently required in addition to site- and clinical situation-specific thrombosis management strategies.

View all citing articles on Scopus

View full text

Original ArticlesAnticoagulation in Children With Mechanical Valve Prostheses

Abstract

Section snippets

Material and Methods

Results

Comment

Ann Thorac Surg

J Thorac Cardiovasc Surg

J Thorac Cardiovasc Surg

J Thorac Cardiovasc Surg

Am J Cardiol

J Thorac Cardiovasc Surg

Ann Thorac Surg

J Am Coll Cardiol

J Thorac Cardiovasc Surg

Ann Thorac Surg

Original Articles
Anticoagulation in Children With Mechanical Valve Prostheses