Malabsorption causing failure of pharmacological therapy in the treatment of atrial fibrillation.

We report a case of atrial fibrillation (AF) refractory to medical management. The patient had previously undergone extensive gastric and small bowel surgery. Subsequently we demonstrated malabsorption of administered anti-arrhythmics as the cause of her refractory AF. Malabsorption, even to lesser degrees and from other causes should be considered in cases of unexplained therapeutic refractoriness.