100 Free Mccqe1 Questions (All Accurately Answered)

A 62-year-old man is being treated for an acute myocardial infarction. He originally came to the ED with substernal chest pain and diaphoresis. Given his risk factors of hypertension, diabetes, tobacco use, and family history, he is considered high risk. An ECG in the ED reveals a left-bundle branch pattern, and cardiac enzymes are elevated slightly. After a focused evaluation in the ED, the patient receives IV thrombolytics. Although his bundle branch pattern never resolves, the patient is chest pain-free and haemodynamically stable after thrombolysis. Two days later, however, the patient reports episodes of recurrent chest discomfort and shortness of breath overnight. In evaluating for potential myocardial reinfarction, which of the following is the most appropriate diagnostic test? - Creatinine kinase - Dynamic ECG changes - Lactate dehydrogenase - Myoglobin levels - Troponin I level {Ans: Creatinine kinase CK, total levels and specific MB fraction, are elevated as early as 3 hours after onset of chest pain and have a duration of no more than 2 days, peaking within 18-24 hours Myoglobin is the first enzyme elevated and lasts no more than 1 day, but is nonspecific to AMI Troponin levels increase in 3-12 hours, peak in approximately 1