TRAINING and EDUCATION

Each month in “ You Make the Call ,” we ’ ll pick a challenging clinical question submitted through the Consult-a-Colleague program and post the expert ’ s response . But , what would YOU do ? We ’ ll also pose a submitted question and ask you to send your responses . See how your answer matches up to the experts in the next print issue .

This month , Jean Marie Connors , MD , discusses how long a 31-year-old patient should continue anticoagulation and the recommendations for pregnancy .

A 31-year-old female , who had a recent miscarriage at six weeks of pregnancy , was participating in boot camp . She developed sudden onset left arm pain and numbness and was found to have brachial and axillary artery thromboses . She underwent an emergent thrombectomy . She was noted to have a dual brachial system , and a subacute thrombus was removed . An ECHO was negative for cardiac thrombus or defect . Her angiogram was negative for stenosis or dissection . A hypercoaguable workup was negative . The patient was placed on rivaroxaban ; she wants to conceive again as soon as she can . How long should she continue anticoagulation , and any recommendations regarding pregnancy ?

Jean Marie Connors , MD Assistant Professor Brigham and Women ’ s Hospital Harvard Medical School Boston , MA

This young woman with high estrogen state presented with acute arterial thrombosis of the left upper extremity while participating in high-intensity exercise at “ boot camp ,” which likely involved upper extremity exercise . She was appropriately treated with an emergent thrombectomy to restore arterial blood flow and placed on anticoagulation with rivaroxaban .

Effort-induced thrombosis is a syndrome of upperextremity thrombosis in young patients following vigorous exercise that involves significant use of the arms ( such as long-distance swimming , pitching , gymnastics , or other sports ). Paget – Schroetter syndrome is a disease associated with these types of thrombotic complications , which occur more commonly as venous events , than arterial events . In young patients , both effort-induced venous and arterial thromboses are usually the result of thoracic outlet syndrome ( TOS ), which must be considered in this patient .

With TOS , anatomic variations of the structures in the thoracic outlet can result in compression of the axillary or subclavian arteries , veins , or nerves , with resultant thromboses . These variants can include cervical ribs and other bony abnormalities , as well as variations in muscle anatomy that affect the size of the space that the vessels traverse .

This patient should be evaluated for the presence of a cervical rib , as it is found in more than 90 percent of young patients with arterial TOS . Imaging that has already been performed can be reviewed for the presence of a cervical or anomalous rib , but often specific arm positioning is needed to demonstrate compression . If this patient is found to have a bony abnormality , surgical thoracic outlet decompression should be performed , as the rate of recurrent arterial thrombotic events is high . If an anatomic defect can be corrected , then the risk of recurrence is dramatically lowered and three months of anticoagulation is sufficient , without the need to continue anticoagulation during pregnancy . Rivaroxaban is a small molecule and likely crosses the placenta ; its use is contraindicated in pregnancy . The hypercoagulable state post-miscarriage might have contributed to the development of the arterial thrombotic event , in addition to TOS . You could consider testing for antiphospholipid antibodies if evaluation for TOS is negative .

DISCLAIMER : ASH does not recommend or endorse any specific tests , physicians , products , procedures , or opinions , and disclaims any representation , warranty , or guaranty as to the same . Reliance on any information provided in this article is solely at your own risk .

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• Anemias

• Hematopoietic cell transplantation

• Hemoglobinopathies

• Hemostasis / thrombosis

• Lymphomas

• Lymphoproliferative disorders

• Leukemias

• Multiple myeloma & Waldenström macroglobulinemia

• Myeloproliferative disorders

• Myelodysplastic syndromes

• Thrombocytopenias

Assigned volunteers (“ colleagues ”) will respond to inquiries within two business days ( either by email or phone ).

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