Use of fondaparinux in a pregnant woman with pulmonary embolism and heparin-induced thrombocytopenia

Heparin induced thrombocytopenia in pregnancy: A therapeutic challenge case report and literature review

The anticoagulants of choice for the prevention and treatment of venous thromboembolic disease during pregnancy are unfractionated heparin and low-molecular-weight heparin. Heparin-induced thrombocytopenia (HIT) is introduced as a rare but critical side effect of heparin products raising the thromboembolic event paradoxically. Here, we present a case of HIT in pregnancy with challenging management due to coincidence of lupus anticoagulant (LA) and limited anticoagulant options in the pharmaceutical market of our country of residence. We describe a 6-week pregnant patient with deep venous thrombosis (DVT) and pulmonary thromboembolism (PTE), which developed HIT during antenatal care. Therapeutic anticoagulation was initiated with argatroban, then switched to apixaban due to limited access to argatroban. Another therapeutic challenge was the concurrent incidence of LA. The interdisciplinary care team decided on adding up warfarin and scheduled termination at 12 weeks regarding the hazardous condition of the patient. We also reviewed related case literature to convey a new insight into managing pregnancy-related HIT. HIT is a pro-coagulatory and lethal complication associated with heparin therapy that can be diagnosed by clinical suspicion, the 4T score system, and confirmatory laboratory analyses. Alternative anticoagulation is the cornerstone of the treatment and an interdisciplinary plan will be worthwhile to make the best clinical decision regarding the critical situation and least the thromboembolic events mortality during pregnancy.

Prevention of Venous Thromboembolism during Pregnancy and the Puerperium with a Special Focus on Women with Hereditary Thrombophilia or Prior VTE-Position Paper of the Working Group in Women's Health of the Society of Thrombosis and Haemostasis (GTH)

Venous thromboembolism (VTE) is a major cause of maternal morbidity during pregnancy and the postpartum period. Because there is a lack of adequate study data, management strategies for the prevention of VTE during pregnancy have mainly been deduced from case-control and observational studies and extrapolated from recommendations for non-pregnant patients. The decision for or against pharmacologic thromboprophylaxis must be made on an individual basis weighing the risk of VTE against the risk of adverse side effects such as severe bleeding complications. A comprehensive, multidisciplinary approach is often essential as the clinical scenario is made more complex by the specific obstetric context, especially in the peripartum period. As members of the Working Group in Women's Health of the Society of Thrombosis and Haemostasis (GTH), we summarize the evidence from the available literature and aim to establish a more uniform strategy for VTE risk assessment and thromboprophylaxis in pregnancy and the puerperium. In this document, we focus on women with hereditary thrombophilia, prior VTE and the use of anticoagulants that can safely be applied during pregnancy and the lactation period.

Prophylaxis and Therapy of Venous Thrombotic Events (VTE) in Pregnancy and the Postpartum Period

Venous thromboembolisms and pulmonary embolisms are one of the main causes of morbidity and mortality in pregnancy. The increased risk of thrombotic events caused by the physiological changes during pregnancy alone does not justify any medical antithrombotic prophylaxis. However, if there are also other risk factors such as a history of thromboses, hormonal stimulation as part of fertility treatment, thrombophilia, increased age of the pregnant woman, severe obesity or predisposing concomitant illnesses, the risk of thrombosis should be re-evaluated - if possible by a coagulation specialist - and drug prophylaxis should be initiated, where applicable. Low-molecular-weight heparins (LMWH) are the standard medication for the prophylaxis and treatment of thrombotic events in pregnancy and the postpartum period. Medical thrombosis prophylaxis started during pregnancy is generally continued for about six weeks following delivery due to the risk of thrombosis which peaks during the postpartum period. The same applies to therapeutic anticoagulation after the occurrence of a thrombotic event in pregnancy; here, a minimum duration of the therapy of three months should also be adhered to. During breastfeeding, LMWH or the oral anticoagulant warfarin can be considered; neither active substance passes into breast milk.

Efficacy and safety of venous thromboembolism prophylaxis with fondaparinux in women at risk after cesarean section

Objectives

Cesarean section is associated with an increased risk for venous thromboembolism (VTE). The safety and efficacy of primary prophylaxis of fondaparinux, a synthetic sulfated pentasaccharide heparin analog, in women at risk after cesarean section is uncertain.

Methods

This was a retrospective study of 295 cases of pregnant women presenting to a tertiary referral center of Nara, Japan, to evaluate the usefulness of thromboprophylaxis with fondaparinux after cesarean delivery between 2011 and 2012. Patients were initially received unfractionated heparin (once 5,000 IU subcutaneously, twice a day), starting 6 hours after cesarean section for 24 hours, and then treated with fondaparinux (once 2.5 mg daily, subcutaneously) for 5 days. The primary efficacy end-point was an improvement in the incidence of symptomatic VTE or fatal post-cesarean pulmonary thromboembolism. The primary safety end-point was major bleeding during treatment.

Results

There were neither any episodes of symptomatic VTE cases nor maternal deaths. A total of 10 patients had a bleeding event. Major bleeding complication was observed in 2 (0.68%) of 295 patients receiving fondaparinux. Non-major bleeding into critical sites was observed in 8 patients, often at surgical sites, and recovery was not delayed.

Conclusion

This study demonstrates the safety and efficacy of fondaparinux in women at high risk of VTE after cesarean section. Large phase trials comparing clinical outcomes with fondaparinux across a wide spectrum of patients are needed to confirm these observations.

A systematic review on the use of new anticoagulants in pregnancy

New anticoagulants such as direct factor Xa inhibitors and direct thrombin inhibitors have been recently developed, but their experience in pregnancy is limited. This review therefore aims to systematically search for studies on the use of these newer anticoagulants in pregnancy and the puerperal period. Searches were performed on electronic databases MEDLINE (from 1966), EMBASE (from 1974) and the Cochrane Library, until October 2011 using terms of 'pregnancy', 'puerperium', 'breastfeeding' and names of specific anticoagulants. The search yielded 561 citations and 11 studies (10 on fondaparinux, 1 on ximelagatran) were included. Newer anticoagulants (fondaparinux, hirudin and argatroban) on the limited evidence appear not to have adverse pregnancy outcomes, but there is currently no experience of new oral anticoagulants (rivaroxaban, apixaban, betrixaban or dabigatran) use in pregnancy. There is a need for reporting on new oral anticoagulation use in pregnancy to provide more information about the safety and risks to the fetus in utero.

Diagnosis and management of maternal thrombocytopenia in pregnancy

Thrombocytopenia is a common finding in pregnancy, occurring in approximately 7-10% of pregnancies. It may be a diagnostic and management problem, and has many causes, some of which are specific to pregnancy. Although most cases of thrombocytopenia in pregnancy are mild, and have no adverse outcome for either mother or baby, occasionally a low platelet count may be part of a more complex disorder with significant morbidity and may be life-threatening. Overall, about 75% of cases are due to gestational thrombocytopenia, 15-20% secondary to hypertensive disorders; 3-4% due to an immune process, and the remaining 1-2% made up of rare constitutional thrombocytopenias, infections and malignancies. In this review, a diagnostic approach to investigating thrombocytopenia in pregnancy is presented, together with antenatal, anaesthetic and peri-natal management issues for mother and baby, followed by a detailed discussion on the specific causes of thrombocytopenia and the management options in each case.

Fondaparinux - data on efficacy and safety in special situations

New anticoagulants promise to have better efficacy, more safety and/or a better manageability than traditional anticoagulants. However, knowledge is limited regarding special situations such as renal insufficiency, obesity, pregnancy, long-term therapy, heparin-induced thrombocytopenia, treatment in patients with mechanical heart valves, use for children, and in patients with a high risk of thromboembolic complications. These situations have rarely or even never been the objective of randomised controlled trials. The purpose of the present article is to summarize and discuss available data on efficacy and safety in these special situations for one of the first new anticoagulants, the indirect factor-Xa inhibitor fondaparinux. Furthermore, we discuss safety in licensed indications and management of bleeding complications and comment on measuring of drug concentration in plasma.