Case 5 / 2018 – Acute Respiratory Failure and Cardiogenic Shock in a Patient in the First Trimester of Pregnancy with Mechanical Mitral Valve Prosthesis Implant

Clinical aspects

The case reported is of a 36-year-old pregnant woman with repaired complex congenital heart disease, with a mechanical mitral valve prosthesis implanted 28 years before, paroxysmal atrial fibrillation, and a history of thromboembolism, a triad that characterizes a high thromboembolic risk.

Notwithstanding, the patient maintained the adequate anticoagulation goal (INR = 3) until the pregnancy diagnosis, when the anticoagulation regimen of warfarin was replaced by enoxaparin due to the risk of fetal warfarin syndrome, which occurs between the 6^th and 12^th weeks of gestation (characterized by nasal hypoplasia, dysplasia of the bony epiphyses, limb deformities, neurological and respiratory problems). However, there is less evidence of the erratic bioavailability and distribution of enoxaparin during pregnancy, although it constitutes a current challenge to define the best anticoagulation strategy in this population with high thromboembolic risk.

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