Anticoagulation After Bariatric Surgery: Beyond Warfarin

While Direct Oral Anticoagulants (DOACs) have proven noninferior or superior to Vitamin K Antagonists (VKAs/warfarin) in many contexts, questions remain around which agent to choose after bariatric surgery. Here we present the case of a 44-year-old woman with a complex medical history, including subtotal gastrectomy and Roux-en-Y gastric bypass, who presented with a panoply of symptoms including gross hematuria and International Normalized Ratio (INR) >12 on warfarin. After inflammatory processes were ruled out, she was diagnosed with numerous vitamin and mineral deficiencies, including vitamin K, vitamin C, and vitamin D. Warfarin was switched to apixaban. Peak apixaban levels were measured at goal, demonstrating therapeutic absorption of this drug even in the setting of chronic, severe malabsorption. This case demonstrates the importance of considering nutritional deficiencies as a unifying diagnosis and challenges the belief that DOACs should be avoided after bariatric surgery.