A 36-Year-Old Woman with Mitral Valve Prolapse Comes to the Office

question 430

Multiple Choice

A 36-year-old woman with mitral valve prolapse comes to the office due to dyspnea and is found to have severe mitral valve regurgitation.  Two weeks later, the patient undergoes elective mechanical mitral valve replacement.  Continuous heparin infusion and oral warfarin are initiated following the procedure.  Coagulation studies during admission are as follows:  The patient achieves the goal of INR ≥2.5 on postoperative day 5 and heparin infusion is discontinued.  Which of the following likely caused the delay in achieving therapeutic INR in this patient?

• A)Clotting factors generated before warfarin initiation
• B)Formation of anti-platelet factor 4/heparin antibodies
• C)High total body stores of vitamin K
• D)Induction of an enzyme that metabolizes warfarin
• E)Slow onset of steady-state drug concentration

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Definitions:

Post-Traumatic Stress Disorder

A mental health condition triggered by experiencing or witnessing a terrifying event, leading to persistent flashbacks, nightmares, and severe anxiety.

Generalized Anxiety Disorder

A mental health condition characterized by persistent and excessive worry about various aspects of daily life, beyond what might be expected from the situation.

Pervasive Worrying

A chronic and excessive concern about a variety of topics, events, or activities, which is difficult to control and affects daily functioning.

Specific Phobias

Intense, irrational fears of specific objects or situations, such as heights, spiders, or flying, that lead to avoidance behavior.