title: Clinical evaluation is better: myoglobin estimation used singly as a discriminant for early acute myocardial infarction does not well identify patients who will benefit from thrombolytic therapy.
abstract: We have examined the use of serum myoglobin concentration in the management of cases of suspected acute myocardial infarction (AMI). In a series of 51 patients myoglobin, used as a discriminant, correctly identified 97% (28/29) of cases as AMI with one false positive. Initial clinical judgement based on history, examination and the electrocardiogram correctly identified 66% (19/29) of cases with one false positive. These patients were given streptokinase. However, in these further identified AMI patients, 78% (7/9) had small enzyme rises with non-Q wave infarction and/or non-ST elevation and therefore may not have benefited from thrombolytic therapy in contrast to the Q wave/raised ST segment infarcts with large enzyme rises identified by clinical means. Enthusiasm for myoglobin estimation, where used as a discriminant for AMI, as a direct pointer to thrombolysis in the early diagnosis of AMI should be tempered by this finding.
authors.affiliation: Department of Chemical Pathology, Worthing Hospital, Sussex, UK.
authors.forename: H J
authors.initials: HJ
authors.lastname: Southgate
authors.forename: A J
authors.initials: AJ
authors.lastname: Fry
authors.forename: T
authors.initials: T
authors.lastname: Pickett
authors.forename: A
authors.initials: A
authors.lastname: Jones
authors.forename: M
authors.initials: M
authors.lastname: Signy
mesh_terms: D000368:Aged; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000175:diagnosis* / Q000188:drug therapy; D009211:Myoglobin / Q000032:analysis*; D012680:Sensitivity and Specificity; D013300:Streptokinase / Q000627:therapeutic use; D015912:Thrombolytic Therapy
chemical_list: D009211:Myoglobin; D013300:Streptokinase