Anticoagulant Therapy in a Pregnant Woman with May-Thurner Syndrome

Management of May Thurner Syndrome in Pregnant Patients

May Thurner Syndrome contributes to thromboembolic disease and can cause significant morbidity in pregnant patients secondary to exaggerated anatomic relationships and physiologic changes in the hematologic system favoring thrombogenesis. Because this condition is both underrecognized and underreported, management in pregnant and postpartum patients is based on expert opinion without any formal evidence-based guidance. Herein, we review five pregnancies in four patients with May Thurner Syndrome and general management strategies. Through collaborative and multidisciplinary care, patients with May Thurner Syndrome can be safely and successfully managed during pregnancy and the postpartum period with appropriate anticoagulation.

May-Thurner Syndrome Is Aggravated by Pregnancy

This study aims to emphasize that asymptomatic patients with undiagnosed and asymptomatic May-Thurner syndrome (MTS) may firstly develop severe compression during pregnancy. A 40-year-old woman, G1P0, at 22 weeks of twin gestation presented with left lower extremity edema and pain. One twin was structurally normal while the other had bilateral renal agenesis with oligohydramnios. Magnetic resonance venography (MRV) revealed severe compression of the left iliac vein by the right iliac artery without evidence of deep vein thrombosis (DVT). Conservative treatment with anticoagulant prophylaxis was instituted throughout the rest of pregnancy and postpartum period. She was also complicated with severe pre-eclampsia, a cesarean section was performed due to a prolapsed cord at 27 weeks of gestation, and she gave birth to a surviving baby weighing 1100 g. In conclusion, this case report provides evidence that pregnancy can disclose a subtle May-Thurner anatomy to be symptomatic without DVT. Successful pregnancy outcomes could be achieved with conservative treatment and anticoagulant prophylaxis.

Double venous compression due to duplicated inferior vena cava-induced right common iliac vein thrombosis

Venous compression syndromes are caused by extrinsic venous compression of anatomical structures, such as the adjacent arteries and bones. Chronic venous compression and pulsative vibratory arterial pressure accelerate the development of deep vein thrombosis. Herein, we report the first case of double venous compressions due to a duplicated inferior vena cava-induced right-sided common iliac vein thrombosis. The thrombus was induced by left-sided inferior vena cava entrapment and right-sided common iliac vein compression, resembling nutcracker syndrome and May-Thurner syndrome, respectively. Bypass flow of the right inferior vena cava rendered the right lower extremity asymptomatic. Once daily anticoagulation edoxaban was effective. Congenital venous anomalies and bypass formations should be considered when a common iliac vein thrombus without symptoms in the lower extremities is observed, and a lifelong periodical follow-up is mandatory, even after remission.

The hemodynamic effects of pregnancy on the lower extremity venous system

OBJECTIVE

Pregnancy has significant effects on the lower extremity venous system. Increasing venous pressure and blood volume, in combination with reduced flow rates within the deep veins, predisposes pregnant women to both primary and secondary chronic venous insufficiency (CVI). This review article highlights the specific physiologic and hemodynamic changes that occur during pregnancy and examines the nonpharmacologic, pharmacologic, and invasive interventions that are appropriate for both prophylaxis and treatment of CVI and venous thromboembolism (VTE).

METHODS

This study is a review article of the key literature related to VTE and CVI in pregnancy.

RESULTS

Significant hemodynamic changes occur in the lower extremities during pregnancy. Although well documented and essential to fetal development, these changes can have a negative impact on the maternal lower extremity venous circulation. Consequences of pregnancy can result in venous disease only during pregnancy or, particularly in the multiparous patient, can progress to CVI. An abundance of literature and guidelines exist for the management of VTE during pregnancy; however, the quality and extent of literature based around the management of primary CVI during pregnancy are modest at best.

CONCLUSIONS

The physiologic changes throughout the arterial and venous systems during pregnancy are well documented. However, there is a paucity of data available to construct guidelines for care, particularly in the pregnant patient with symptomatic superficial venous insufficiency. Further investigation in the form of prospective randomized trials is required to establish appropriate guidelines for treatment.