Secondary Thromboprophylaxis in Hereditary Thrombophilia

Aims: The aim of this study is to show how the coagulation laboratory and clinical findings worked together in the management of a patient with hereditary thrombophilia and pulmonary embolism (PE) in terms of diagnosis, the choice of anticoagulation treatment and the duration of secondary thromboprophylaxis.

Study Design: A case report with the presentation of clinical and laboratory findings, treatment and long-term follow up of the patient.

Place and Duration of Study: Institute of Transfusion Medicine and University Clinics of Cardiology, St Cyril and Methodius University, Skopje, Macedonia in the period from February 2015 and December 2017.

Case Presentation: Computer tomography confirmed the diagnosis of PE in a 32-year-old man who was admitted to the cardiology emergency department with D-dimer level of 5980 ng/mL after an episode of syncope. After the initial anticoagulation with unfractionated heparin 30.000i.e./24 h, enoxaparin 80 mg/12 h and acenocoumarol were introduced. The therapeutic INR rang could not be achieved so the acenocoumarol was switched to rivaroxaban 2x15 mg/day. One year later the anticoagulation with rivaroxaban 20 mg/day was discontinued. Thrombophilia testing included: prothrombin (PTB), Factor V Leiden and methylene tetrahydrofolate reductase (MTHFR) C677T gene mutation, as well as antiphospholipid antibodies, antithrombin, protein C and S.

Results: The patient was homozygous for the PTB. His parents were heterozygous for the same mutation; his mother also being heterozygous for MTHFR C677T. His brother was compound heterozygote for PTB and MTHFR C677T and his sister was heterozygous for the PTB. Coagulation status monitoring showed hypercoagulability (APTT was 24-26 seconds) and increment of D-dimer (2100-2400 ng/ml) when rivaroxaban was discontinued and normal APTT (28-38 seconds) and D-dimer (< 500 ng/mL) when it was reintroduced.

Conclusion: According to the laboratory findings and also having in mind that this was a second episode of a thrombotic event, we decided for an extended secondary thromboprophylaxis. Although it sometimes implies that it will be continued life-long we consider worthwhile to apply the patient-oriented approach to the decision when and whether to terminate anticoagulation.