A 50-year-old male with past medical history of ischemic heart disease and prasugrel hypersensitivity in the form of generalized rash underwent elective PCI with one drug-eluting stent (DES) to the left anterior descending artery (LAD). He was subsequently started on dual antiplatelet therapy with aspirin 81 mg daily and ticagrelor 90 mg twice a day.\nTwo days following discharge, the patient was complaining of severe shortness of breath with minimal exertion, and occasionally at rest. He denied any fevers, chills, productive cough, orthopnea, paroxysmal nocturnal dyspnea or lower limb edema. The patient’s dyspnea was heavily investigated with basic labs, cardiac biomarkers, imaging of the chest, and repeat transthoracic echocardiogram. All results came back within normal limits. The patient’s dyspnea was deemed secondary to ticagrelor use and the drug was discontinued, with subsequent improvement of his symptoms. Given his history of prasugrel hypersensitivity and current intolerance to ticagrelor, the patient was started on clopidogrel. Three days later, he presented to the emergency department (ED) with a rash that started on his chest and spread to his arms and face (Figure ).\nThe patient was diagnosed with cutaneous hypersensitivity to clopidogrel. Given the patient’s need for dual antiplatelet therapy and previously documented prasugrel hypersensitivity as well as intolerance to ticagrelor, shifting to any of them was not an option.\nReviewing the literature, three management strategies have been described for clopidogrel hypersensitivity, including switching to another agent, implementing a desensitization protocol, and a six-day course of steroids without clopidogrel discontinuation. A shared decision was made to implement the latter approach however with a slow taper over a three-week period. The patient was started on oral prednisone 30 mg twice a day for five days, followed by a decrease of 5 mg/day every three days for 15 days. On his one-week follow-up, the patient was well-tolerating clopidogrel with complete resolution of his symptoms and no significant side effects from steroids. The patient showed no side effects related to steroids on his one-month follow-up.
A 69-year-old African gentleman with a medical history of coronary artery disease after percutaneous coronary intervention to his right coronary artery in 2014 for a non-ST-segment elevation myocardial infarction and prior contrast-media allergy presented to the emergency department with atypical angina.\nShortly after his arrival, he was seen by the emergency medicine physician who initiated an acute coronary syndrome antiplatelet regimen comprising both oral aspirin 325 mg and ticagrelor 180 mg. Vital signs revealed mild hypertension with a blood pressure of 147/94 mmHg, normal pulse rate of 74 beats per minute, and an oxygen saturation of 99% on pulse oximetry on room air. His physical examination was significant for left-sided chest wall tenderness only. A 12-lead electrocardiogram (EKG) revealed sinus rhythm with a 1st degree atrioventricular block and a left anterior fascicular block with prior inferior myocardial infarction. There were no acute ischemic changes. His cardiac biomarkers were normal (peak serum levels of creatine phosphokinase-MB fraction (CK-MB) and troponin T were 1.5 ng mL−1 (normal range, 1–5 ng mL−1) and 0.034 ng mL−1 (normal range, 0-0.1 ng mL−1), respectively) and did not reflect a myocardial infarction.\nApproximately 1 hour after ticagrelor administration, the patient reported a constellation of symptoms which included worsening chest pain, sudden-onset respiratory distress, and generalized urticaria. His repeat physical examination revealed new-onset periorbital edema and angioedema (). He was immediately administered 200 mg intravenous hydrocortisone, 100 mg intravenous ranitidine, and 10 mg intravenous chlorphenamine with nebulized albuterol and ipratropium, and his symptoms resolved shortly thereafter (within an hour).\nBased on the clinical scenario, the patient's tentative diagnosis was ticagrelor-induced hypersensitivity reaction with angioedema as this was the only new medication he was given (he was on daily maintenance aspirin for his CAD and previously tolerated a 1-year course of clopidogrel after drug-eluting stent implantation). It was also noted that he was not on an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker. He was subsequently transferred to cardiac care unit for further observation and supportive care. The following day, a 2D transthoracic echocardiogram revealed a preserved left ventricular ejection fraction of 60% without regional wall motion abnormalities. He reported that his symptoms were much improved and was hemodynamically stable. His clinical angioedema completely resolved. The patient's atypical angina completely abated, and subsequent cardiac biomarkers and electrocardiograms were unremarkable. As a result, inpatient coronary angiography was not pursued as his TIMI risk stratification was considered low to moderate risk, and outpatient exercise stress echocardiography was the preferred management strategy to assess for ischemia. He was safely discharged on guideline-recommended, optimal medical therapy comprising aspirin, clopidogrel (which he previously tolerated as DAPT for his prior stent implantation without any adverse effects), beta-blocker, mineralocorticoid receptor antagonist with high-intensity statin, and a tapered course of oral steroid therapy.