ABSTRACT Background The coronavirus disease (COVID-19) pandemic affected the prompt diagnosis and treatment of Acute myocardial infarction (AMI). Aim: To characterize the clinical profile of patients with AMI during the COVID-19 pandemic, comparing them with a historical cohort. Material and Methods: A case-control study of 96 patients with AMI transferred to a high-volume percutaneous coronary intervention (PCI) hospital between March and July 2020, and a historical cohort of 269 patients transferred during the same period in 2019. Results: When comparing patients transferred during the pandemic with those of the historical cohort, the former were younger (63 ± 12 vs 68 ± 12 years, p < 0.01), had a higher frequency of hypertension (66 vs 45%, p < 0.01) and of smoking (40% vs 25%, p < 0.01). Also, during COVID-19 outbreak a higher proportion of patients had ST-elevation AMI consulting > 12 hours from the onset of symptoms (44 vs 0%, p < 0.01), a higher median door-to-device time (4 vs 3 hours, p < 0.01), a higher use of primary percutaneous coronary intervention (97 vs 71%, p < 0.01), and higher frequencies of cardiogenic shock (20 vs 4%, p < 0.01) and mechanical complications (10% vs 2%, p < 0.01). Patients during COVID pandemic had a higher thirty-day overall (20 vs 1.4%, p < 0.01) and cardiovascular mortality (13 vs 1%, p < 0.01). During the outbreak, 40% of patients had positive COVID-19 status, which was a predictor for thirty-day overall mortality (Risk ratio 2.90; 95% confidence intervals 1.14-7.36). Conclusions: During the pandemic patients with AMI exhibited delays in consultations and treatment, higher morbidity, and increased mortality. COVID-19 positivity was associated to worse thirty-day overall survival.