Impact of Thyroid Metabolism on the Course of INR Levels in a Patient with Systemic Anticoagulation Suffering from Amiodarone-Induced Thyrotoxicosis

Abstract

We report the case of a 60 year old female patient on continuous systemic anticoagulation therapy with coumarin due to mechanical aortic valve replacement and a more than 3 years lasting amiodarone therapy due to severe ventricular extrasystoles suffering from amiodarone induced thyrotoxicosis (AIT). During the course of AIT, showing different thyroid metabolic conditions, INR levels revealed a course closely related to the thyroid conditions indicating a significant and clear-cut effect of both hyper- and hypothyroidism on systemic anticoagulation therapy with coumarin. This continuous interaction of different thyroid metabolic conditions and the anticoagulation state could be well documented in the presented case over a time period of approximately five months.

Key words

systemic anticoagulation - thyroid metabolism - amiodarone-induced thyrotoxicosis - INR

References

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