• Syncope in elderly patients is often the initial manifestation of myocardial infarction (MI). Small elevations in creatine kinase—myocardial band (CK-MB) activity following syncope may represent MI, transient myocardial hypoperfusion, or insignificant background activity. To determine the prevalence and prognostic significance of minimal CK-MB elevations in elderly patients with syncope, serial serum CK-MB activities and subsequent survival experiences were determined for elderly syncope patients with and without MI, and for agematched nonsyncopal controls. While all syncope patients with MI by specific clinical criteria had one or more abnormal CK-MB levels (>5 U/L) and died within 31 months, 10% of syncope patients without MI and 10% of controls had abnormal CK-MB with no impact on mortality. Using standard clinical laboratory techniques, minimal elevation in CK-MB was found in 10% of elderly subjects with and without syncope and probably had no prognostic significance.
(Arch Intern Med 1987;147:1321-1323)