The case of a 62-year-old diabetic and smoker male who was under study in another hospital due to anemia, thrombopenia and hematuria of several months of evolution is presented. The patient was admitted to the coronary unit for an acute extensive transmural myocardial infarction and treated with t-PA. A few hours later the patient presented hematuric urine, a decrease in hemoglobin and platelets and acute renal insufficiency. Hematologic study confirmed the diagnosis of paroxystic nocturnal hemoglobinuria. The evolution of the patient was poor despite intensive medical treatment requiring hemodialysis. The patient presented cardiac tamponade and died. The role of hematologic disease in acute myocardial infarction and the treatment and evolution of the coronary syndrome in the context of the disease are discussed.