A 44-year-old South Asian male with no significant medical or family history presented to the emergency department with typical chest pain and shortness of breath. He did not report any significant social history, and his review of systems was unremarkable. His vital signs indicated systolic blood pressures of 156/92 mmHg, heart rate of 108 beats per minute, respiratory rate of 20 breaths per minute, with an oxygen saturation of 97% on room air. The brief physical examination was normal. An emergency 12-lead electrocardiogram revealed marked, 6-millimeter ST-segment elevation in leads V1-V6 with reciprocal ST-depressions in the inferior leads, II, III, and aVF.\nHe was immediately administered oral aspirin, ticagrelor load, high-intensity rosuvastatin in addition to an intravenous nitroglycerin infusion and subsequently proceeded for primary PCI. During cardiac catheterization, it was discovered that the patient had the much dreaded "widow-maker" lesion - a proximal left anterior descending (LAD) artery occlusion with high-grade thrombus burden. He successfully underwent transfemoral drug-eluting stent (DES) implantation after thrombus aspiration with a Boston Scientific Corporation (Marlborough, Massachusetts) SYNERGY® everolimus DES.\nPost-procedure, the patient developed translucent bullous lesions with surrounding erythema on the distal flexor aspect of the right forearm, for which he promptly received intravenous hydrocortisone and chlorphenamine. At this juncture, the tentative diagnosis was a contrast-media reaction (Ultravist®️ 370, Bayer AG, Leverkusen, Germany). During the subsequent hospitalization, the patient was hemodynamically stable. He was subsequently discharged on guideline-directed medical therapy on DAPT with ticagrelor, high-intensity statin, low-dose beta-blocker, and angiotensin-receptor neprilysin inhibitor, and mineralocorticoid receptor antagonist, in addition to oral antihistamine and topical steroid cream therapies. A skin biopsy was not performed, as there were no available dermatologists during the coronavirus disease 2019 (COVID-19) pandemic.\nThe patient contacted the interventional cardiologist one-week post-procedure and alerted him that the lesions were worsening despite the therapies. At that time, a measured decision was taken to transition him to clopidogrel (loading dose of 300 milligrams, followed by daily maintenance dose, 75 milligrams) and rivaroxaban 2.5 milligrams twice daily. Over the following four days, the bullous lesions spontaneously ruptured, with resolving erythema and induration. After a further three-day period, the lesions almost fully healed with areas of hyperpigmentation. There was no generalized body or mucosal involvement. Provocation tests with ticagrelor were not performed (Figure ).
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.