Intraoperative floppy iris syndrome and warfarin: coincidence or side effect?

Previous studies demonstrate how the intraoperative floppy iris syndrome (IFIS) is associated with different risk factors, including systemic diseases and alpha-1 antagonist drugs, the main one being tamsulosin which alleviates benign prostate hypertrophia symptoms.1 This drug is very efficient for urologists as it delays or avoids prostate surgery although it complicates in an extraordinary manner ophthalmological surgery, not only for cataracts but also combined posterior pole surgery. Recently we have treated a 58-year-old patient with heart surgery history 2 years back due to dual valve deficiency and in treatment with warfarin since then. This patient does not have a history of previous or present therapies with alpha-1 antagonist drugs or herbal preparations. He underwent combined surgery (23G posterior vitrectomy with phacoemulsification) in the left eye due to retina detachment with macular involvement in which excessive fluctuation was observed together with iris herniation due to the incision and miosis which caused extraordinary complications in the cataracts and retinal detachment surgery. Recently, Ali and Alsheikh described 13 eyes with intrasurgery flaccid iris syndrome (IFIS) and with history of past and/or present treatment with warfarin.2 Warfarin is an oral anticoagulant with vitamin K antagonist action utilized in the long-term prophylaxis of thromboembolic complications associated to several diseases.3 It is used as prophylaxis and treatment of deep vein thrombosis and in pulmonary thromboembolism. In cardiac surgery it is indicated in the substitution of heart valves. In cardiology it is used after heart infects as it reduces the risk of sudden death. Its ability to interact with other drugs constitutes one of the main drawbacks of warfarin, including enhancements with tamsulosin. It is important to take into account that warfarin (3-[acetonylbenzyl]-4-hydroxicumarine) (C19H16O4) and