Screening for acute myocardial infarction in elderly patients with collapse, confusion and falls

Falls, collapse and confusion are frequent causes of admission to hospital in the elderly, and myocardial infarction (MI) can present atypically. The study was designed to assess the incidence of MI in this group of patients and provide information on the value of screening methods. A total of 142 elderly patients with a mean age of 83 years (range 76-99) were admitted with unexplained collapse, confusion or falls. Serial ECGs and cardiac enzymes were performed. Eighty-two patients (59%) had normal ECGs; of these, 80 (98%) had normal or non-significantly elevated cardiac enzymes; 72/108 patients without chest pain had normal ECGs compared with 10/32 who had chest pain (p < 0.01). Cardiac enzymes were elevated in 5/108 without chest pain and 10/32 with chest pain (p < 0.01). Thirty-two (23%) had chest pain, 14 (10%) had an acute MI. In those presenting with chest pain, 32% had an MI, compared with only 1.9% of those without chest pain (p < 0.01); 18% of patients with an initially abnormal ECG had an MI compared with only 5% of those with a normal ECG (p = 0.02). None of the patients with a normal ECG who were free of chest pain were subsequently proven to have an MI. Cardiac enzymes are often non-specifically elevated in this group of patients due to muscle injury. The incidence of MI is low in patients without chest pain and we would not advocate routine screening with serial cardiac enzymes, unless there is chest pain or an abnormal 12-lead ECG on admission.