The physician is considering the initial complaint of onset severe chest pain while patient was descending stairs. An electrocardiogram shows rapid (120 beats per minute) sinus rhythm with no elevation in the S-T segment, neither T wave inversion nor new Q wave occurrence. Cues against heart disease. She does not immediately dismiss her observations but rather holds the diagnosis in abeyance: she is still considering myocardial injury in spite of the initial lack of evidence (ECG results or elevated enzymes.)