Early aspirin desensitization in unstable patients with acute coronary syndrome: Short and long-term efficacy and safety.

Background: Aspirin hypersensitivity is not a rare condition among patients with acute coronary syndrome. However, despite the publication of several successful desensitization protocols, the procedure is not as widespread as expected. We present a cohort of patients with acute coronary syndrome undergoing aspirin desensitization to evaluate its short- and long-term efficacy and safety and to reinforce data from previous studies. Methods: Of 1306 patients admitted to our Coronary Care Unit between February 2011 and February 2013, 24 (1.8%) had a history of aspirin hypersensitivity. All 24 patients underwent an eight-dose aspirin desensitization protocol (0.1, 0.3, 1, 3, 10, 25, 50 and 100 mg of aspirin given by mouth every 15 minutes) after premedication with antihistamines and corticosteroids or antileucotrienes. Previously prescribed blockers and angiotensin-converting enzyme inhibitors were not discontinued. All patients were desensitized within 72 hours of admission. Those requiring urgent catheterization (five patients with ST segment elevation myocardial infarction) were desensitized within 12 hours of catheterization and the remainder before catheterization. Results: All patients were successfully desensitized and only one presented with an urticarial reaction. The five patients with ST segment elevation myocardial infarction were treated with abciximab until desensitization was complete. All but one patient underwent catheterization and 20 underwent percutaneous coronary intervention, most (66%) with the implantation of a bare metal stent. At follow-up (a minimum of 6-24 months), only two patients had discontinued aspirin, both due to gastrointestinal bleeding, and no hypersensitivy reaction had occurred. Conclusions: Aspirin desensitization is effective and safe in unstable patients with acute coronary syndrome in both the short and long term.